Canadian Journal of Fisheries and Aquatic Sciences · 2020. 3. 3. · 82 Rockfishes of the genus...
Transcript of Canadian Journal of Fisheries and Aquatic Sciences · 2020. 3. 3. · 82 Rockfishes of the genus...
Draft
Contrasting effects of coastal upwelling on growth and recruitment of nearshore Pacific rockfish (Genus Sebastes)
Journal: Canadian Journal of Fisheries and Aquatic Sciences
Manuscript ID cjfas-2019-0179.R1
Manuscript Type: Article
Date Submitted by the Author: 05-Dec-2019
Complete List of Authors: Markel, Russell; University of British Columbia, ZoologyShurin, Jonathan; UCSD,
Keyword:COASTAL WATERS < Environment/Habitat, AGE DETERMINATION < General, DISPERSAL < General, LIFE HISTORY < General, OTOLITHS < General
Is the invited manuscript for consideration in a Special
Issue? :Not applicable (regular submission)
https://mc06.manuscriptcentral.com/cjfas-pubs
Canadian Journal of Fisheries and Aquatic Sciences
Draft
Rockfish recruitment Markel and Shurin 1
1
2 Contrasting effects of coastal upwelling on growth and recruitment of
3 nearshore Pacific rockfish (Genus Sebastes)
4
5 Russell W. Markel1,2 and Jonathan B. Shurin3,4
6
7 1Department of Zoology
8 University of British Columbia
9 Vancouver, BC, Canada V6T 1Z4
10
11 2Outer Shores Institute
12 P.O. Box 361
13 Cobble Hill, BC V6R 1L0
14
15 3Section of Ecology, Behavior and Evolution
16 University of California San Diego
17 9500 Gilman Dr., #0116
18 La Jolla, CA 92093
19
20 4Corresponding author. Email: [email protected]
21 Running head: Upwelling dynamics and rockfish recruitment
22 Keywords: Larval dispersal; upwelling dynamics, rockfish, otolith microstructure; larval growth;
23 recruitment.
Page 1 of 42
https://mc06.manuscriptcentral.com/cjfas-pubs
Canadian Journal of Fisheries and Aquatic Sciences
Draft
2
24 Abstract
25 Knowledge of processes underlying recruitment is critical for understanding marine population
26 dynamics and their response to ocean climate. We investigated the relationship between coastal
27 upwelling and early life history of Black Rockfish (Sebastes melanops), a mid-water aggregating
28 species, and CQB Rockfishes (a solitary benthic species complex including S. caurinus, S. maliger and
29 S. auriculatus), between two oceanographically distinct years on the west coast of Vancouver Island,
30 Canada. We analysed otolith microstructure to determine parturition and settlement dates, pelagic
31 durations, and pre- and post-settlement growth rates. High CQB Rockfish recruitment in 2005 was
32 associated with prolonged downwelling and warm ocean temperatures, late parturition dates, fast pre-
33 settlement growth, short pelagic durations, and small size-at-settlement. In contrast, high Black
34 Rockfish recruitment in 2006 was associated with strong upwelling and cool ocean temperatures, slow
35 pre-settlement growth and protracted pelagic durations. Pre-settlement growth of both Rockfish
36 complexes increased with high sea surface temperature, but was unrelated to chlorophyll-a
37 concentration. Our results indicate that the same oceanographic conditions give rise to fast pre-
38 settlement growth and short pelagic durations for both groups, but that different factors lead to strong
39 recruitment in each.
40
41 Introduction
42 Variation in the frequency and magnitude of recruitment has strong effects on marine population
43 sizes, persistence, and connectivity (Armsworth 2002; Caley et al. 1996; Cowen and Sponaugle 2009;
44 Doherty and Williams 1988). Recruitment of marine fishes is often highly variable, with large cohorts
45 separated by many years of weak or no recruitment (Houde 2009). Because many years can pass
46 between years of high recruitment, recruitment events may be ‘stored’ in adult populations with
47 generation times that match or exceed intervals between episodic years of strong recruitment (Hjort
Page 2 of 42
https://mc06.manuscriptcentral.com/cjfas-pubs
Canadian Journal of Fisheries and Aquatic Sciences
Draft
3
48 1914; Secor 2007). Warner and Chesson (1985) proposed the ‘storage effect’ as a mechanism to
49 explain species coexistence in systems where recruitment is limited by juvenile habitat (Sale 1977).
50 The storage effect also promotes population resilience through interaction among overlapping
51 generations by maintaining populations over long periods of unfavourable conditions for recruitment
52 (Secor 2007). Thus, understanding processes underlying recruitment variability and year-class strength
53 is critical to predicting population and community responses to exploitation, climate change, and
54 conservation and management strategies.
55 Recruitment variation in space or time may be driven by reproduction, survival through the larval
56 stage or onshore advection and settlement of juveniles into benthic habitats (Pepin 1991). Most coastal
57 fishes and invertebrates have complex life histories where recruitment in populations is decoupled from
58 local production by widely dispersed pelagic eggs and larvae that experience high and variable
59 mortality (Leggett and Deblois 1994; Pepin and Myers 1991; Roughgarden et al. 1988). Following
60 pelagic stages lasting from days to several months and dispersal distances from 10’s to 100’s of km
61 (Shanks 2009), juveniles settle into benthic habitats and local adult populations (Roughgarden et al.
62 1985). Post-settlement density-dependent mortality may obscure the effects of larval recruitment
63 variation on population numbers (Caley et al. 1996; Hixon and Webster 2002). Ocean conditions
64 affecting larval mortality are major drivers of annual recruitment success (Doherty and Fowler 1994;
65 Field and Ralston 2005; Houde 1989; Jenkins and King 2006; Pepin 1991). Infrequent spatial and
66 temporal alignment of ocean conditions favoring larval growth and survival are likely to create narrow
67 windows of reproductive opportunity and success (Agostini and Bakun 2002; Cury and Roy 1989;
68 Cushing 1990; Hedgecock 1994; Lasker 1975).
69 Years of strong recruitment likely result from ocean conditions favoring high larval growth and/or
70 survival (e.g. Bergenius et al. 2002; Jenkins and King 2006), and/or high rates of larval delivery
71 (Bertness et al. 1992). Although adult body condition and larval production vary with ecosystem
72 productivity (Lenarz and Echeverria 1986; Woodbury 1999), larval production and recruitment are
Page 3 of 42
https://mc06.manuscriptcentral.com/cjfas-pubs
Canadian Journal of Fisheries and Aquatic Sciences
Draft
4
73 often uncoupled in time (Carr and Syms 2006a). Larval fish mortality is size-dependent, decreasing
74 rapidly with increasing body size. Factors promoting high growth rates may therefore also reduce
75 mortality (Hare and Cowen 1997; Houde 1989; Otterlei et al. 1999; Pepin 1991). Survival through the
76 larval stage is a function of daily mortality (i.e. losses to starvation and predation) and the number of
77 days over which mortality accrues (Houde 2009; Leggett and Deblois 1994). Pelagic duration is
78 therefore a major contributing factor to cumulative mortality and recruitment strength (Pepin and
79 Myers 1991). The oceanographic processes affecting larval growth, pelagic duration, and onshore
80 transport (i.e., delivery or retention, Selkoe et al. 2006; Warner and Cowen 2002), therefore shape the
81 population dynamics of many marine species.
82 Rockfishes of the genus Sebastes (Family Scorpaenidae) comprise one of most ecologically and
83 economically important groups of marine fishes along the Pacific coast of North America (Love et al.
84 2002). Courtship and copulation generally occurs in the fall, and females give birth to live young (i.e.
85 parturition) during the winter and early spring. Adult females may release more than a million larvae
86 that are approximately 3-7 mm long at parturition. Larvae develop into pelagic juveniles after one to
87 two months (Love et al. 2002), and remain in the water column and offshore for additional weeks to
88 months before moving to inshore settlement habitats and adult populations (Moser and Boehlert 1991).
89 Following settlement, growth and condition are closely tied to population density and habitat
90 availability (Markel and Shurin 2015). Extreme longevity (100-200 years in some species; Munk 2001),
91 low reproductive rates, and stochastic recruitment make rockfishes vulnerable to over-exploitation
92 (Leaman 1991; Parker et al. 2000; Williams et al. 2010). As a result, rockfish populations are
93 increasingly the focus of protection by marine protected areas and catch restrictions (e.g. Haggarty et al.
94 2016a; Haggarty et al. 2016b; Yamanaka and Logan 2010). Because local population persistence
95 depends on replenishment (Cowen and Sponaugle 2009), incorporating the processes that regulate the
96 frequency, magnitude, and spatial scales of recruitment variability is key to designing effective marine
97 protected area networks (Carr and Reed 1993; Gaines et al. 2003). As different rockfish year classes
Page 4 of 42
https://mc06.manuscriptcentral.com/cjfas-pubs
Canadian Journal of Fisheries and Aquatic Sciences
Draft
5
98 show uneven representation in fisheries (Laidig et al. 2007; Mason 1998; Mearns et al. 1980; Ralston
99 and Howard 1995), the processes driving rockfish recruitment may determine population abundance
100 and fisheries landings (but see Haggarty et al. 2017).
101 Recruitment variation of nearshore rockfishes in the northeastern Pacific coastal margin is
102 associated with upwelling (Ainley et al. 1993; Bjorkstedt et al. 2002; Caselle et al. 2010a; Laidig et al.
103 2007; Larson et al. 1994; Lenarz et al. 1995; Ralston and Howard 1995; Rau et al. 2001; Wilson et al.
104 2008). Upwelling occurs seasonally along eastern boundaries of ocean basins during spring and
105 summer months when northerly winds push the low-density surface Ekman layer offshore and cause a
106 drop in nearshore sea level. As a result, cold and nutrient-rich deep water flows inshore and upwells
107 into the euphotic zone where it fuels primary production (Cury and Roy 1989). Fig. 1 summarizes the
108 hypothesized relationships among upwelling, temperature, marine productivity, pre-settlement growth
109 and mortality, and settlement rates of rockfishes. Cross-shelf flows during upwelling may transport
110 pelagic larvae offshore or onshore, depending on the depth of larvae relative to the thermocline (Mace
111 and Morgan 2006; Shanks and Brink 2005). Coastal upwelling influences rockfish recruitment both by
112 inhibiting or facilitating nearshore retention or onshore movement of larvae and pelagic juveniles, and
113 by regulating ocean temperature and primary productivity and therefore pre-settlement growth rates
114 (Fig. 1). Larval growth and survival may be promoted by upwelling due to increased primary
115 production, or reduced due to low temperature. Caselle et al. (2010a) found that coastal upwelling was
116 the best oceanographic predictor of delivery of pelagic juvenile rockfishes to nearshore adult habitats.
117 However, evidence for the effects of upwelling on recruitment is mixed (Shanks and Brink 2005),
118 and attempts to relate interannual recruitment variation to the timing and magnitude of upwelling have
119 met with mixed success (Caselle et al. 2010a; Caselle et al. 2010b; Laidig et al. 2007; Wilson et al.
120 2008). In a related study, Lotterhos and Markel (2012) examined relationships between coastal
121 upwelling and Black rockfish (S. melanops) reproductive success, and revealed contrasting effects on
122 the abundance of recruits. Although both warmer ocean temperatures and the strength of upwelling
Page 5 of 42
https://mc06.manuscriptcentral.com/cjfas-pubs
Canadian Journal of Fisheries and Aquatic Sciences
Draft
6
123 were positively correlated with the abundance of recruits, warmer ocean temperatures were positively
124 correlated with larval growth rates and the effective number of breeders, whereas upwelling was
125 negatively correlated with the effective number of breeders. These results suggest that ocean
126 temperature affects survival and recruitment via larval growth, while the strength of upwelling affects
127 survival through oceanographic processes determining larval delivery. These patterns, however, may be
128 limited to species of rockfishes with similar distribution of larvae in the water column (Lenarz et al.
129 1995).
130 Nearshore rockfishes can be subdivided into “mid-water aggregating” and “solitary-benthic”
131 complexes, comprised of species representing primarily two subgenera that differ remarkably in their
132 morphology, ecology, and evolutionary histories (Hyde and Vetter 2007). Species within the subgenus
133 Sebastosomus, are mid-water aggregating species (e.g. S. flavidus, S. melanops, S. mystinus, S.
134 serranoides), generally associated with shallow semi-pelagic habitats, are darkly or drably coloured,
135 and have elongated bodies with greatly reduced head spines. In contrast, subgenus Pteropodus is
136 comprised of solitary benthic species (e.g. S. carnatus, S. caurinus, S. chrysomelas, S. maliger, S.
137 nebulosus, S. rastrelliger), that are generally associated with shallow high-relief habitats, have deep
138 bodies, often with distinct coloration patterns, and strong head spination. Lenarz et al. (1995) and Carr
139 and Syms (2006) observed that during El Niño years (1992/1993 and 1997/1998), high recruitment of
140 solitary benthic rockfishes corresponded to above average ocean temperatures and weak upwelling that
141 favoured onshore advection. In contrast, mid-water aggregating rockfishes recruited heavily during a
142 La Niña event in 1999 that was associated with strong upwelling and cold ocean temperatures.
143 Our objective was to understand how ocean climate variability affects early life history stages and
144 recruitment of nearshore Pacific rockfishes off the west coast Vancouver Island, Canada. We measured
145 recruitment over six years (2005-2010) that included two exceptionally strong recruitment events. CQB
146 complex recruitment (a species complex of solitary-benthic rockfishes including Copper (S. caurinus),
147 Quillback (S. maliger), and Brown (S. auriculatus) rockfishes with juveniles that cannot be
Page 6 of 42
https://mc06.manuscriptcentral.com/cjfas-pubs
Canadian Journal of Fisheries and Aquatic Sciences
Draft
7
148 distinguished morphologically) was high in 2005. In contrast, Black Rockfish (S. melanops), a mid-
149 water aggregating species, was high in 2006. These recruitment events provided the opportunity to
150 investigate how the timing and magnitude of coastal upwelling differentially affect early life history
151 attributes and recruitment success of rockfishes with contrasting life history strategies. We compared
152 oceanographic conditions between 2005 and 2006 with juvenile rockfish life history parameters using
153 otolith microstructure analysis to determine parturition and settlement dates, pelagic durations, and pre-
154 and post-settlement growth rates. We assessed the effects of upwelling intensity, ocean temperature,
155 and primary productivity on these early life history attributes and corresponding recruitment success.
156 Our goal was to determine whether the conditions that favor growth of pelagic larvae increase
157 settlement and recruitment into the nearshore habitat, and whether these effects vary among solitary
158 benthic and mid-water aggregating rockfish complexes.
159 Methods
160 Study system
161 This study was conducted in Barkley Sound (48o 50.0’N, 125o 22.0’W) on the southwest coast
162 of Vancouver Island, British Columbia, at the northern-most boundary of the California Current Large
163 Marine Ecosystem. This region shows seasonal transitions between upwelling-favourable northwest
164 winds (spring/summer) and downwelling-favourable southerly winds (fall/winter) characteristic of the
165 California Current System (Shanks and Eckert 2005). The Vancouver Island Coastal Current (VICC) is
166 a narrow current (5-25 km) driven primarily by buoyancy flux from coastal runoff exiting the Strait of
167 Georgia via the Strait of Juan de Fuca (Hickey et al. 1991). Following the spring transition, the VICC
168 continues in a reduced band flowing northward towards Brooks Peninsula (Hickey et al. 1991;
169 Thomson and Ware 1996).
170 We used Standard Monitoring Units for the Recruitment of Fishes (SMURFs; Ammann 2004)
171 to assess rockfish recruitment between 2005 and 2010. We deployed SMURFs at the seaward edge of
Page 7 of 42
https://mc06.manuscriptcentral.com/cjfas-pubs
Canadian Journal of Fisheries and Aquatic Sciences
Draft
8
172 kelp forests (Macrocystis pyrifera) where they were moored horizontally 1.5 meters below the surface.
173 We used a Benthic Ichthyofaunal Net for Coral/Kelp Environments (BINCKE; Anderson and Carr
174 1998) and snorkeling equipment to collect all fish within SMURFs on each sampling date. All young-
175 of-the-year (YOY) rockfishes were identified, weighed, measured (total length). Copper (Sebastes
176 caurinus), quillback (S. maliger), and brown (S. auriculatus) rockfishes were grouped as “CQB”
177 rockfishes because of difficulty distinguishing early post-settlement juveniles. Beginning in 2010, we
178 reduced our sampling program whereby recruitment estimates and collection of post-settlement
179 rockfishes for otolith analyses took place only in August. We therefore report the average number of
180 rockfish per SMURF in August between 2005 and 2010 (Fig. 2). Full details of sampling sites and
181 locations are described in Markel et al. (2017).
182
183 Age and parturition date determination
184 We used otolith microstructure analysis to determine parturition dates, settlement dates, and
185 pelagic durations of juvenile Black and CQB complex rockfishes collected by SMURFs in 2005 and
186 2006. Deposition of daily increments by juvenile rockfishes has been validated for early post-
187 settlement rockfishes (Kokita and Omori 1999; Laidig et al. 1991; Plaza et al. 2001; Woodbury and
188 Ralston 1991; Yoklavich and Boehlert 1987). We did not conduct additional validation experiments
189 and assumed for both groups that each increment represents one day of growth, and that the total
190 number of increments corresponds to the number of days between parturition and capture (i.e. age). To
191 ensure representation of all sizes and ages we pooled Black and CQB Rockfishes collected in 2005 and
192 2006 over all sampling dates and randomly selected individuals from 10 mm size classes. We mounted
193 right sagittal otoliths on glass slides in clear Crystalbond 509 thermoplastic epoxy with the sulcus
194 facing downward and the anti-rostral end angled downward approximately 30-40 degrees from
195 horizontal. We measured otolith lengths (the longest distance across the sagittae) using a digital image
196 of the entire otolith. All digital images were obtained using a JVC 3-CCD camera mounted on a
Page 8 of 42
https://mc06.manuscriptcentral.com/cjfas-pubs
Canadian Journal of Fisheries and Aquatic Sciences
Draft
9
197 dissecting microscope or an inverted transmission light microscope. We used the digital imagery
198 software Auto-Montage Pro (version 5.03, Syncroscopy, Beacon House, Cambridge) for image capture
199 and otolith microstructure measurements.
200 We exposed daily growth increments using 30µm and 3µm lapping paper and viewed them at
201 40x-1000x magnification. We did not use otoliths if the primordium or large sections of increments
202 were not visible. Dark checks at the edge of the nuclear radius of numerous Sebastes species have been
203 identified as extrusion or parturition checks (Laidig and Ralston 1995; Miller and Shanks 2004; Plaza
204 et al. 2001; Ralston et al. 1996). Consistent with these studies, we found checks at median nuclear radii
205 of 11.77 µm for S. melanops and 12.55 µm for CQB Rockfishes. When visible we measured increment
206 widths from the primordium to parturition checks, and subsequently between each increment along a
207 straight line to the most distal portion of the anti-rostral end. In most cases parturition checks were not
208 observed and increments closest to the primordium were not visible. Instead, we started counts and
209 measurements where increments first became continuously visible to a maximum distance of 25 m
210 from the core. If increments were not continuously visible beyond 25 m from the core these otoliths
211 were rejected from our analyses. We estimated the number of increments between the first
212 measurement and the nuclear radius at parturition by subtracting the median radii of parturition checks
213 (above) and dividing the difference by the mean width of the first five increments measured. Sample
214 micrographs of a black rockfish otolith at 100x, 200x, 400x, and 1000x magnification are shown in
215 Supplemental Figure S1.
216
217 Settlement date determination
218 Settlement marks on the otoliths of early post-settlement rockfishes have been identified and
219 validated previously (Amdur 1991; Gallagher 2007; Pasten et al. 2003). We determined settlement
220 dates using the transition-centered method (Pasten et al. 2003; Wilson and Mccormick 1997; Wilson
Page 9 of 42
https://mc06.manuscriptcentral.com/cjfas-pubs
Canadian Journal of Fisheries and Aquatic Sciences
Draft
10
221 and Mccormick 1999). This method uses longitudinal profiles of daily increment width to identify a
222 distinct transition from slow and consistent pre-settlement growth to fast and variable post-settlement
223 growth associated with settlement of reef fishes. In addition, we constructed longitudinal profiles of
224 increment width variance calculated over 5-day intervals and plotted these as 5-day moving averages.
225 We used both types of plot to identify settlement age and date by the increment immediately preceding
226 a distinct transition to persistently rapid and variable growth. To visualize these relationships for each
227 species and year, we centered increment width and variance profiles on designated settlement
228 increments and plotted resulting mean increment widths and variances for the 20 days (increments)
229 preceding and following settlement. We determined settlement dates twice independently using the
230 longitudinal profiles of growth and the moving window and averaged the two readings. We determined
231 pelagic duration by subtracting parturition dates from settlement dates.
232 Finally, we compared the timing of parturition and settlements in 2005 and 2006 to the timing
233 of specific oceanographic events. We focused these comparisons on time periods when the majority of
234 parturition and settlements occurred each year by using the 1st and 3rd quartiles of parturition and
235 settlement date distributions to define parturition and settlement intervals for each rockfish group and
236 year.
237
238 Annual and inter-annual oceanographic variability
239 We obtained daily upwelling index estimates of Ekman transport (m3 s-1100m-1 of coastline) for
240 position 48ºN/125ºW from the Pacific Fisheries Environmental Lab (http://www.pfeg.noaa.gov).
241 Upwelling index values are modeled from recorded wind direction, velocity, and duration. Positive
242 values indicate upwelling-favourable winds and offshore transport of the shallow low-density Ekman
243 layer, and negative values indicate downwelling-favourable winds and onshore transport of the Ekman
244 layer. We obtained daily sea surface temperature (SST) data collected from Amphitrite Point
245 Lighthouse, located at the northwest corner of Barkley Sound from Fisheries and Oceans Canada
Page 10 of 42
https://mc06.manuscriptcentral.com/cjfas-pubs
Canadian Journal of Fisheries and Aquatic Sciences
Draft
11
246 (http://www.pac.dfo-mpo.gc.ca). We obtained satellite-derived estimates of daily chlorophyll
247 concentrations (mg m-3) from Aqua MODIS sensors (http://oceancolor.gsfc.nasa.gov/seadas). We used
248 the SeaDAS Level 3 browser to sample an 11x11 matrix of 4x4 km pixels (1,936 km2) situated at the
249 entrance to Barkley Sound and centered at 48.649oN/125.559oW. Due to cloud cover, data were not
250 available for all days or for all pixels on each day. We derived daily estimates by averaging across
251 pixels on each day and using an 11-day moving average (the shortest interval that gave continuous
252 values), to smooth trends and minimize data gaps.
253 We compared the average ocean conditions experienced by Black and CQB Rockfish cohorts in
254 2005 and 2006 during their pelagic phases. To control for observed differences in pelagic duration, we
255 limited analyses to the first 40 days and 60 days of the pelagic durations of individual CQB and Black
256 rockfishes, respectively. We selected these intervals based on observed pelagic durations for Black and
257 CQB rockfishes in order to maximize interval length and sample sizes. We aligned intervals of all
258 individuals and calculated daily averages of upwelling index values, SST, and chlorophyll-a
259 concentrations.
260
261 Pre- and post-settlement growth rates
262 We compared daily growth rates of Black and CQB Rockfish between 2005 and 2006 by testing
263 for differences in slopes of length-at-age relationships using simple linear regression and ANCOVA. In
264 addition, we constructed longitudinal profiles of average pre- and post-settlement daily increment
265 width. For each annual cohort and rockfish group, we centered individual longitudinal profiles on
266 increments corresponding to settlement dates, and then calculated mean increment width for each
267 increment (day) preceding and following settlement. Finally, we used individual longitudinal profiles
268 of otolith increment width to model individual length-at-age profiles from parturition to collection. This
269 approach allowed us to fit growth models representing each cohort and to estimate the body lengths of
270 individual rockfish at the time of settlement (i.e. size-at-settlement).
Page 11 of 42
https://mc06.manuscriptcentral.com/cjfas-pubs
Canadian Journal of Fisheries and Aquatic Sciences
Draft
12
271 We used the Modified-Fry back-calculation model to estimate body length for each incremental
272 increase in otolith radius (Vigliola et al. 2000; Wilson et al. 2009). This model (Eq. 1) assumes non-
273 linearity between otolith and somatic growth and constrains an allometric body length-otolith radius
274 function through a biologically meaningful intercept as:
275 (Eq.1)𝐿𝑖 = 𝑎 + 𝑒𝑥𝑝[ln (𝐿0𝑝 ― 𝑎) + (ln (𝐿𝑐𝑝𝑡 ― 𝑎) ― ln (𝐿0𝑝 ― 𝑎)) ∗(ln (𝑅𝑖) ― ln (𝑅0𝑝))
(ln (𝑅𝑐𝑝𝑡) ― ln (𝑅0𝑝))]276 where Li is the length of the ith fish at capture in mm, L0p is mean fish body length at first
277 increment (parturition), Ri is otolith radius, R0p is mean otolith radius at first increment (parturition),
278 and Rcpt is otolith radius at capture, and where a L0P bR0P
c The parameters b and c were obtained by
279 fitting a non-linear regression (Eq. 2) to the relationship between fish length and otolith radius:
280 (Eq. 2) 𝐿𝑐𝑝𝑡 = 𝐿0𝑝 ―𝑏𝑅𝑐0𝑝 +𝑏𝑅𝑐
𝑐𝑝𝑡
281 where Lcpt is fish body length at capture, b is the slope of the L-R relationship, and c is the
282 coefficient of allometry. We constructed individual length-at-age profiles by plotting modeled
283 estimates of body length for each daily growth increment from parturition to capture. To represent
284 average growth profiles of each cohort we fit a single growth model to the individual growth profiles
285 comprising each cohort. We compared Von Bertalanffy, Logistic, Gompertz, and Schnute-Richards
286 growth models using Akaike’s Information Criterion (AIC) and found that the Logistic growth model
287 most closely represented the sigmoidal growth trajectories of juvenile rockfishes in this study.
288 (Eq. 3) 𝐿𝑖 =𝑎
1 + 𝑏 ∗ exp ( ― 𝑐 ∗ 𝑎𝑔𝑒)
289 where Li is fish length, a is the asymptotic fish length, b is the inflection point, age is in days
290 since parturition, and c is a relative growth coefficient (Bates and Watts 1988).
291
292 Data analyses
293 All analyses were performed using R (R Core Development Team 2011). We fit logistic growth
294 models to modeled length-at-age profiles of annual Black and CQB Rockfish cohorts using nonlinear
Page 12 of 42
https://mc06.manuscriptcentral.com/cjfas-pubs
Canadian Journal of Fisheries and Aquatic Sciences
Draft
13
295 least squares approximation (R package ‘nls’). To test for inter-annual differences in parturition dates,
296 settlement dates, pelagic durations, and size-at-settlement we used Student’s t-tests.
297 We used simple linear regression to assess the effects of SST (oC) and Chl-a (mg m-3) on pre-
298 settlement growth rates (µm/d) of individuals, and the effects of growth rates (i.e. developmental rates
299 and swimming abilities) and upwelling (i.e. onshore/offshore transport) on pelagic duration. Because
300 increment width increases with body and otolith length, and because pelagic durations vary widely
301 among individuals, we restricted analyses to growth profiles corresponding to 5-40 days and 5-60 days
302 following parturition, for CQB and Black Rockfishes, respectively. We calculated mean upwelling
303 index, SST, and chlorophyll concentrations over dates corresponding to individual growth profiles.
304 We estimated the independent effects of these explanatory variables on growth rates and pelagic
305 durations using hierarchical variance partitioning (R package ‘hier.part’). Hierarchical partitioning is a
306 form of multiple regression that determines the contribution of each predictor to the total explained
307 variance of a regression model, both independently and in conjunction with the other predictors, for all
308 possible candidate regression models. Hierarchical partitioning alleviates the problems of
309 multicollinearity associated with traditional multiple regression approaches (Mac Nally 2002; Mac
310 Nally and Walsh 2004).
311
312 Results
313 Interannual recruitment variability
314 Black Rockfish recruitment varied around 10-fold among years, with strongest recruitment
315 events occurring in 2006 and 2010. High CQB Rockfish recruitment occurred in 2005 and, to a lesser
316 extent, in 2009 (Fig. 2).
317
Page 13 of 42
https://mc06.manuscriptcentral.com/cjfas-pubs
Canadian Journal of Fisheries and Aquatic Sciences
Draft
14
318 Parturition, settlement, and pelagic duration
319 Longitudinal profiles of otolith daily increment width and variance were effective for
320 identifying settlement dates of both Black and CQB Rockfishes (Fig. 3). Pre-settlement growth was
321 clearly differentiated from post-settlement growth by an abrupt transition from small and invariable to
322 large and variable increment widths. Black Rockfish parturition and settlement dates did not differ
323 between the year with weak (2005) and strong (2006) recruitment, but pelagic durations were on
324 average nine days shorter, and settlement dates 12 days earlier, in 2005 (Table 1a). Back-calculated
325 estimates of Black Rockfish size-at-settlement did not differ between years. CQB Rockfish parturition
326 dates were on average 28 days later in 2005 than 2006, while pelagic durations were 12 days shorter,
327 and settlement dates 15 days later, than in 2006. CQB Rockfish were significantly smaller at settlement
328 in 2005 than in 2006 (Table 1b).
329
330 Cohort-specific oceanographic conditions
331 Oceanographic conditions experienced by pelagic larvae and juveniles of Black and CQB
332 Rockfishes differed markedly between 2005 and 2006. Pre-settlement Black Rockfish in 2005
333 experienced downwelling conditions (i.e. negative upwelling index values), warm temperatures, and
334 low primary productivity (Fig. 4 a,c,e). Upwelling increased in 2006 beginning approximately 50 days
335 prior to Black Rockfish settlement, becoming positive approximately 20 days prior to settlement.
336 Strong upwelling began in mid-April of 2006 and resulted in elevated chlorophyll-a levels.
337 CQB Rockfish also experienced markedly different oceanographic conditions between 2005
338 and 2006 both due to parturition dates that occurred later than Black Rockfish in both years, and
339 because parturition dates occurred a month later in 2005 than 2006. In 2005, pre-settlement CQB
340 Rockfish experienced unusually warm and downwelling–favourable ocean conditions during the 40
341 days prior to settlement. In contrast, pelagic larvae and juveniles in 2006 experienced strong upwelling
342 and cool ocean temperatures (Fig 4 b,d,f).
Page 14 of 42
https://mc06.manuscriptcentral.com/cjfas-pubs
Canadian Journal of Fisheries and Aquatic Sciences
Draft
15
343
344 Oceanographic conditions during parturition and settlement intervals
345 Black Rockfish parturitions occurred in mid-late February in both 2005 (10-February to 23-
346 February), and 2006 (12-February to 1-March), during short periods of high upwelling, low SST, and
347 high chlorophyll-a concentrations (Fig. 5 a,c,e). Black Rockfish settlement in 2005 (17-April to 9-May)
348 and 2006 (27-April to 14-May), corresponded to periods of strong upwelling. High Black Rockfish
349 settlement in 2006 occurred through late April and early May during the peak and declining phase of an
350 exceptionally strong upwelling event.
351 CQB Rockfish parturitions (9-April to 29-April), and settlements (24-May to 18-June), in 2005
352 occurred at the end of periods of exceptionally low upwelling and increasing SST and chlorophyll-a
353 levels (Fig. 5 b,d,f). In 2006, CQB parturitions (11-March to 30-March), occurred nearly a month
354 earlier than in 2005 and immediately before upwelling increased in early April and remained above
355 average until mid May when settlement occurred (16-May to 29-May).
356
357 Pre- and post-settlement growth
358 We used the positive correlation between otolith length and body length for both species
359 (Supplemental Fig. S2) to model individual length-at-age profiles using the Modified-Fry back-
360 calculation model (Supplemental Fig. S3). Logistic growth models fitted to back-calculated length-at-
361 age profiles indicate that Black Rockfish pre-settlement growth rates were initially slightly higher in
362 2005 than 2006; however, in 2005 post-settlement growth slowed at approximately 150 days after
363 which 2006 growth rates were faster (Fig. 6a). Fitted growth models for CQB Rockfish show faster
364 pre- and post-settlement growth in 2005 compared to 2006 (Fig. 6b). Length-at-age relationships
365 closely mirrored the modeled comparison of pre-and post-settlement growth. Black Rockfish growth
366 was slightly higher in 2006 (Fig. 6c; ANCOVA, length*year, F = 6.49, P = 0.0123), and CQB
Page 15 of 42
https://mc06.manuscriptcentral.com/cjfas-pubs
Canadian Journal of Fisheries and Aquatic Sciences
Draft
16
367 Rockfish length-at-age was markedly higher in 2005 (Fig. 6d; ANCOVA, length*year, F = 8.19, P =
368 0.0067).
369 Comparison of average daily increment width profiles reinforced these patterns. Black Rockfish
370 grew faster pre-settlement in 2005 than in 2006, but post-settlement growth was faster in 2006 (Fig. 7a).
371 Black Rockfish size-at-settlement was similar in 2005 and 2006, despite the trend towards higher pre-
372 settlement growth in 2005 (Fig. 7a, Table 1). CQB Rockfish pre-settlement increments were
373 consistently wider in 2005 than in 2006, and this trend continued post-settlement (Fig. 7b). Higher
374 CQB Rockfish growth rates (logistic models, length-at-age, and increment width-at-age) in 2005
375 corresponded to significantly smaller sizes-at-settlement (Fig. 7b, Table 1).
376
377 Ocean conditions, growth rates, and pelagic duration
378 We found strong and consistent relationships between Black (Fig. 8) and CQB (Fig. 9) rockfish
379 pre-settlement growth rates, pelagic duration, SST and upwelling. Growth rates increased significantly
380 with increasing SST (Black Rockfish, R2 = 0.2369, F1,54 = 16.76, P = 0.00014; CQB Rockfish, R2 =
381 0.3377, F1,36 = 18.36, P = 0.00013), but not chlorophyll concentrations (Black Rockfish, R2 < 0, F1,54 <
382 0, P = 0.9950; CQB Rockfish R2 = 0.0555, F1,36 = 2.11, P = 0.1547). Pelagic durations decreased with
383 increasing growth rates (Black Rockfish, R2 = 0.2993, F1,54 = 23.07, P < 0.0001; CQB Rockfish, R2 =
384 0.2506, F1,36 = 12.04, P = 0.0014), and increased with upwelling experienced during the 30 days prior
385 to settlement (Black Rockfish, R2 = 0.1996, F1,54 = 13.47, P = 0.0006; CQB Rockfish, R2 = 0.1784,
386 F1,36 = 7.82, P = 0.0082). Hierarchical variance partitioning showed that growth rates of Black and
387 CQB Rockfishes were primarily associated with the independent effects of SST (Black Rockfish =
388 87.7%; CQB Rockfish = 89.8%) but not chlorophyll-a levels (Black Rockfish = 12.3%; CQB Rockfish
389 = 10.2%). Pelagic durations of rockfishes were strongly affected by the independent effects of pre-
390 settlement growth rates (Black Rockfish = 45.4%; CQB Rockfish 61.2%) and the magnitude of
391 upwelling prior to settlement (Black Rockfish = 54.6%; CQB Rockfish = 38.8%).
Page 16 of 42
https://mc06.manuscriptcentral.com/cjfas-pubs
Canadian Journal of Fisheries and Aquatic Sciences
Draft
17
392
393 Discussion
394 Our research reveals distinct responses of mid-water aggregating Black Rockfish and solitary
395 benthic CQB Rockfish growth and recruitment to seasonal and interannual climate variation and its
396 effect on upwelling, temperature and marine productivity. Both complexes showed large interannual
397 variability in early life history attributes (i.e. parturition and settlement dates, growth rates, and pelagic
398 durations) corresponding closely, but in different ways, to specific upwelling events. Black Rockfish
399 reproduce earlier in the year than CQB Rockfish, and upwelling had nearly opposite effects on
400 recruitment although both showed faster growth during times of warmer SST. High CQB Rockfish
401 recruitment was associated with prolonged downwelling-favorable winds, warm ocean temperatures,
402 late parturition dates, high growth rates, and short pelagic durations. In contrast, strong Black Rockfish
403 recruitment was associated with strong upwelling, cool ocean temperatures, slow growth rates, and
404 long pelagic durations. These results provide evidence that high larval growth rates and reduced pelagic
405 durations are not preconditions necessary for strong Black Rockfish recruitment success. Rather,
406 oceanographic processes facilitating onshore delivery of late-stage pelagic juveniles may be the
407 primary determinant of Black Rockfish recruitment success.
408
409 Contrasting oceanographic conditions in 2005 and 2006
410 Oceanographic conditions differed remarkably between 2005 and 2006 on the west coast of
411 Vancouver Island and throughout the northern California Current Large Marine Ecosystem (CCLME).
412 In 2005 the spring transition to upwelling-favourable winds that normally occurs in mid April was
413 delayed by 2-3 months resulting from atmospheric-blocking of the jet stream (Schwing et al. 2006).
414 Prolonged downwelling-favourable winds resulted in vertically-stable ocean conditions, unusually
415 warm sea surface temperatures (Kosro et al. 2006), and low primary productivity (Thomas and
Page 17 of 42
https://mc06.manuscriptcentral.com/cjfas-pubs
Canadian Journal of Fisheries and Aquatic Sciences
Draft
18
416 Brickley 2006). Poleward and onshore displacement of numerous taxa were detected reflecting the lack
417 of cross-shelf offshore Ekman transport that usually occurs at this time of year with the seasonal onset
418 of upwelling (Brodeur et al. 2006). Ecosystem-level effects associated with this event included altered
419 zooplankton community composition (Mackas et al. 2006), recruitment failures of intertidal
420 invertebrates (Barth et al. 2007), seabird breeding failure (Sydeman et al. 2006), and changes in marine
421 mammal foraging behaviour (Newell and Cowles 2006; Weise et al. 2006). In contrast, in 2006 the
422 west coast of Vancouver Island experienced above average upwelling-favourable winds through the
423 spring and summer (D.F.O. 2007). In the same year, intense and prolonged upwelling off the coast of
424 Oregon resulted in the oxygen minimum zone being pulled up onto the continental shelf and causing a
425 large-scale anoxia event that resulted in mass mortalities of benthic invertebrates and displacement of
426 demersal fishes (Chan et al. 2008). Thus, upwelling dynamics in 2005 and 2006 likely represent
427 opposite ends of a continuum of oceanographic variability occurring throughout the CCLME and their
428 corresponding effects on nearshore Pacific rockfish recruitment dynamics. Our results show that the
429 two complexes of Rockfish showed contrasting responses to these opposite extremes in the range of
430 oceanographic conditions experienced off Vancouver Island.
431
432 Effects of upwelling on growth
433 By regulating nearshore ocean temperatures and primary productivity, variable coastal
434 upwelling may affect pre-settlement growth and size-dependent vulnerability to predation, pelagic
435 durations, and cumulative mortality rates of pelagic larvae and juveniles. Larval growth and
436 development rates increase with ocean temperature and are highest near larval thermal tolerance
437 maxima (Houde 1989; Houde 2009; Neuheimer et al. 2011; Pepin 1991). In turn, high developmental
438 rates associated with increasing growth rates can reduce pelagic duration by decreasing the age at
439 which metamorphosis occurs and larval competency is reached (Francis 1994). In contrast, coastal
440 upwelling lowers SST and provides nutrients that fuel primary productivity and may enhance the
Page 18 of 42
https://mc06.manuscriptcentral.com/cjfas-pubs
Canadian Journal of Fisheries and Aquatic Sciences
Draft
19
441 resources available to developing juvenile rockfishes. Therefore, the effects of upwelling on larval
442 growth and mortality depend on whether larval growth is more constrained by ocean temperature or
443 productivity. Upwelling may generate conditions of high productivity and prey abundance where
444 growth is temperature limited, while downwelling corresponds to warm temperatures but low resource
445 availability.
446 We found higher pre-settlement growth rates in both Black and CQB Rockfishes during the
447 warm ocean temperatures of 2005. Furthermore, growth rates varied strongly with SST but not
448 chlorophyll-a, and pelagic durations of both groups were inversely related to growth rates. The highest
449 growth rates and shortest pelagic durations were associated with the warm ocean conditions of 2005.
450 High growth rates and short pelagic durations of CQB Rockfishes were also associated with
451 significantly smaller body sizes (total length) at settlement in 2005. These results support the
452 hypothesis that intense upwelling and low ocean temperatures led to low pre-settlement growth rates,
453 increased pelagic durations and, by extension, high cumulative mortality rates during the pelagic-stage
454 in 2006. Although years of high CQB Rockfish recruitment coincide with higher pre-settlement growth,
455 Black Rockfish demonstrated the opposite pattern: the highest Black Rockfish recruitment we observed
456 was associated with slow pre-settlement growth rates and protracted pelagic durations. These
457 contrasting relationships indicate that Black and CQB Rockfish life histories differ fundamentally with
458 respect to the relative importance of processes affecting larval growth and mortality vs. those affecting
459 larval transport and delivery.
460
461 Parturition and settlement in relation to upwelling events
462 Coastal upwelling may affect pelagic duration and mortality rates of rockfishes if cross-shelf
463 flows inhibit or facilitate movement of pelagic juveniles to adult habitats. We found that CQB Rockfish
464 parturition and settlement intervals in 2005 and 2006 were associated with downwelling-favourable
465 winds (i.e. onshore advection of the surface layer). Short pelagic durations and high recruitment in
Page 19 of 42
https://mc06.manuscriptcentral.com/cjfas-pubs
Canadian Journal of Fisheries and Aquatic Sciences
Draft
20
466 2005 occurred when upwelling intensity remained low throughout the pelagic stage. Long pelagic
467 durations and low recruitment in 2006 occurred when upwelling intensity remained above average
468 throughout the pelagic duration. Thus, these patterns support the ‘upwelling-relaxation’ hypothesis
469 (Cury and Roy 1989; Farrell et al. 1991; Roughgarden et al. 1988; Shanks and Brink 2005), and
470 suggest that downwelling and onshore advection of the surface layer reduce pelagic durations and
471 facilitate nearshore retention or onshore movement of CQB Rockfish larvae and pelagic juveniles.
472 Parturition and settlement intervals associated with downwelling events also suggest that CQB
473 Rockfish larvae and pelagic juveniles occupy shallow surface layers above the thermocline (Shanks
474 and Brink 2005).
475 In contrast to CQB Rockfish, Black Rockfish parturition and settlement intervals in 2005 and
476 2006 were associated with periods of above average upwelling. Black Rockfish parturition intervals in
477 2005 and 2006 occurred in mid February and corresponded closely to short but strong upwelling events
478 that resulted in a rapid decrease in SST and increase in Chl-a. The extent to which these events
479 contributed to recruitment in these years is unknown. One possibility is that high primary productivity
480 coinciding with spawning may have increased very early larval growth and survival rates (Cury and
481 Roy 1989). Most Black Rockfish settlement in 2006 occurred during the peak and declining phase of a
482 strong upwelling event. In contrast to CQB Rockfish, this pattern suggests that Black Rockfish pelagic
483 juveniles may occupy deep-water layers below the thermocline (Shanks and Brink 2005). Hierarchical
484 variance partitioning revealed that although pre-settlement growth rates of both complexes contribute
485 substantially and independently to variable pelagic durations, the independent effects of upwelling
486 intensity experienced in the 30 days prior to settlement was higher for Black Rockfish than for CQB
487 Rockfish (55% and 39% respectively). These results indicate that ocean conditions favourable for high
488 larval growth rates and survival are not necessary for high settlement and recruitment rates of Black
489 Rockfish. Rather, exceptional oceanographic events favoring onshore movement of pelagic juveniles,
490 in this case strong upwelling, may be primary determinants of Black Rockfish recruitment. Consistent
Page 20 of 42
https://mc06.manuscriptcentral.com/cjfas-pubs
Canadian Journal of Fisheries and Aquatic Sciences
Draft
21
491 with these findings, Lotterhos and Markel (2012) found that high Black Rockfish recruitment in 2006
492 was associated with a low effective number of breeders (i.e. low allelic richness and high reproductive
493 variance), also indicating the pre-eminent role of transportation processes and resulting narrow
494 windows of opportunity favouring the success of relatively few breeding individuals (i.e. high
495 reproductive variance). However, persistently poor ocean conditions for larval production, growth, and
496 survival are expected to underlie chronically low rockfish recruitment success, regardless of flow
497 regimes that may inhibit or facilitate larval delivery (Caselle et al. 2010a; Cury and Roy 1989; Laidig et
498 al. 2007). Our results highlight the importance of episodic oceanographic events for spatial and
499 temporal patterns of recruitment success that differ among species or complexes.
500
501 Contrasting Black and CQB Rockfish life histories
502 Synchronous recruitment among different species across large spatial scales suggests that suites
503 of oceanographic variables favor taxa with similar early life histories (Field and Ralston 2005;
504 Sponaugle and Cowen 1997). Our data add to a growing number reporting distinct recruitment patterns
505 of mid-water aggregating and solitary benthic complexes of nearshore rockfishes (Carr and Syms
506 2006b; Lenarz et al. 1995). Both complexes showed faster post-settlement growth in the year when
507 they experienced strong recruitment. The species in our study are members of two diverse groups
508 containing many species belonging to the genus Sebastes, therefore the contrast between the two life
509 history strategies may be relevant to a broader suite of species. We note that in their phylogenetic
510 reconstruction of the genus Sebastes, Hyde & Vetter (2007) propose that elongate body plans and semi-
511 pelagic lifestyles of mid-water aggregating species are derived characteristics closely associated with
512 pronounced increases in upwelling and primary productivity in the western Pacific Ocean
513 approximately nine million years ago.
514 Our study supports evidence that solitary benthic and mid-water aggregating rockfishes exhibit
515 distinct responses to coastal upwelling. One possible explanation for the differential recruitment
Page 21 of 42
https://mc06.manuscriptcentral.com/cjfas-pubs
Canadian Journal of Fisheries and Aquatic Sciences
Draft
22
516 success of mid-water aggregating and solitary benthic species during upwelling vs. downwelling,
517 respectively, is the differential use of deep vs. shallow depth strata by pelagic stages. Recent studies
518 have demonstrated that the effects of coastal upwelling on the pelagic stages of marine organisms are
519 taxon-specific, and depend strongly on their vertical location in the water column relative to the
520 thermocline (Mace and Morgan 2006; Shanks and Brink 2005). Lenarz et al. (1995) investigated this
521 hypothesis and found that larvae of solitary benthic species were more abundant higher in the water
522 column than mid-water aggregating species, and therefore more likely to benefit from onshore
523 advection of surface waters during downwelling events. Conversely, mid-water aggregating rockfish
524 larvae were more abundant in deep water and therefore more likely to benefit from onshore advection
525 during upwelling. Although the west coast of Vancouver Island is an active upwelling zone and
526 conforms to the general patterns offshore advection of surface layers and concomitant onshore flow of
527 cold and nutrient-rich deep layers (Ware and Thomson 2005), we have no information about how
528 upwelling events affect the environment in the deeper pelagic habitat of pre-settlement Black Rockfish.
529 Black Rockfish use of deep water habitat also implies tolerance, if not preference, for low ocean
530 temperatures (Neuheimer et al. 2011). Black Rockfish and other mid-water aggregating species spawn
531 in the early winter (January-March) and have pelagic durations lasting 2-4 months. CQB Rockfish and
532 other solitary benthic species spawn in early spring (March-May) and have pelagic durations of 1-2
533 months. We found that both Black and CQB Rockfish pre-settlement growth rates increased, and
534 pelagic durations decreased, with increasing ocean temperature. Therefore, as a result of their earlier
535 parturition and protracted pelagic durations, Black Rockfish larvae experience colder ocean
536 temperatures and are likely to be more vulnerable to slow growth and high pelagic mortality. However,
537 the fact that high recruitment success of Black Rockfish did not coincide with high larval growth rates
538 or short pelagic durations in 2006 indicate that favourable transportation processes were more
539 important determinants of successful recruitment (Lotterhos and Markel 2012). The difference in
540 pelagic juvenile body sizes of Black and CQB Rockfish likely mitigates vulnerability to predation and
Page 22 of 42
https://mc06.manuscriptcentral.com/cjfas-pubs
Canadian Journal of Fisheries and Aquatic Sciences
Draft
23
541 processes affecting onshore movement. The smallest early post-settlement Black Rockfish that we
542 collected in Barkley Sound are approximately 35-40 mm TL, whereas CQB Rockfish are 20-25 mm TL.
543 Because large body sizes are associated with enhanced swimming and foraging abilities (Green and
544 Fisher 2004; Pepin 1991), Black Rockfish larvae and pelagic juveniles may compensate metabolically
545 for low ocean temperatures by increasing prey intake rates.
546
547 Conclusions
548 The ecological and economic importance of Pacific rockfishes has fuelled extensive research to
549 understand relationships among physical oceanographic processes, recruitment success, and year-class
550 strength (Bjorkstedt et al. 2002; Caselle et al. 2010a; Caselle et al. 2010b; Field and Ralston 2005;
551 Laidig et al. 2007; Laidig et al. 1991; Lotterhos and Markel 2012; Ralston and Howard 1995; Wilson et
552 al. 2008; Woodbury and Ralston 1991). Our study adds to a growing understanding of the contrasting
553 ways in which mid-water aggregating and solitary benthic rockfishes are affected by upwelling. The
554 distinct early life history attributes of mid-water aggregating and solitary benthic rockfishes suggest
555 that these groups may differ in terms of dispersal and population connectivity. Pelagic duration and
556 recruitment success are fundamental determinants of population connectivity and persistence (Cowen
557 and Sponaugle 2009). The long pelagic durations and higher recruitment success of Black Rockfish and
558 other mid-water aggregating species (Carr and Syms 2006), suggests relatively high potential for
559 connectivity within regional meta-populations. In contrast, short pelagic durations and low recruitment
560 rates of CQB Rockfishes may indicate lower connectivity and threaten persistence of solitary benthic
561 rockfish populations, and lead to slower responses to protection by marine protected areas (Fogarty and
562 Botsford 2007; Lipcius et al. 2008). Our study also shows that species responses to climate variability
563 depend greatly on life history traits, suggesting that ongoing climate change will produces winners and
564 losers among marine taxa (Harley et al. 2006).
Page 23 of 42
https://mc06.manuscriptcentral.com/cjfas-pubs
Canadian Journal of Fisheries and Aquatic Sciences
Draft
24
565
566 Acknowledgements- We thank Stefan Dick for help in the field, and Britt Keeling for analyses of
567 otolith microstructure. Funding was provided by the National Sciences and Engineering Research
568 Council of Canada (NSERC) through a Discovery Grant to J. B. Shurin and a graduate fellowship to
569 R.M. Additional funding was provided to Tom Tomascik from the Parks Canada Species at Risk
570 Inventory fund, Western and Northern Service Centre, and Pacific Rim National Park Reserve of
571 Canada. Research vessel and field and lab equipment were supported by a Canadian Foundation for
572 Innovation (CFI) grant to J.S. Hank Baker and two anonymous reviewers provided helpful comments
573 on the manuscript.
Page 24 of 42
https://mc06.manuscriptcentral.com/cjfas-pubs
Canadian Journal of Fisheries and Aquatic Sciences
Draft
25
574 Literature Cited
575 Agostini, V. N., and A. Bakun. 2002. 'Ocean triads' in the Mediterranean Sea: physical mechanisms 576 potentially structuring reproductive habitat suitability (with example application to 577 European anchovy, Engraulis encrasicolus). Fisheries Oceanography 11: 129-142.578 Ainley, D. G., W. J. Sydeman, R. H. Parrish, and W. H. Lenarz. 1993. Ocean factors influencing 579 distribution of young rockfish (Sebastes) in central California-a predators prespective. 580 California Cooperative Oceanic Fisheries Investigations Reports 34: 133-139.581 Amdur, J. R. 1991. The validation of a settlement mark on the otoliths of the blue rockfish 582 Sebastes mystinus. M.Sc. San Francisco State University.583 Ammann, A. J. 2004. SMURFs: standard monitoring units for the recruitment of temperate reef 584 fishes. Journal of Experimental Marine Biology and Ecology 299: 135-154.585 Anderson, T. W., and M. H. Carr. 1998. BINCKE: a highly efficient net for collecting reef fishes. 586 Environmental Biology of Fishes 51: 111-115.587 Armsworth, P. R. 2002. Recruitment limitation, population regulation, and larval connectivity in 588 reef fish metapopulations. Ecology 83: 1092-1104.589 Barth, J. A. and others 2007. Delayed upwelling alters nearshore coastal ocean ecosystems in the 590 northern California current. Proceedings of the National Academy of Sciences of the 591 United States of America 104: 3719-3724.592 Bates, D., and D. Watts. 1988. Nonlinear Regression Analysis and Its Applications. Wiley.593 Bergenius, M. A. J., M. G. Meekan, D. R. Robertson, and M. I. Mccormick. 2002. Larval growth 594 predicts the recruitment success of a coral reef fish. Oecologia 131: 521-525.595 Bertness, M. D., S. D. Gaines, E. G. Stephens, and P. O. Yund. 1992. Components of Recruitment in 596 Populations of the Acorn Barnacle Semibalanus-Balanoides (Linnaeus). Journal of 597 Experimental Marine Biology and Ecology 156: 199-215.598 Bjorkstedt, E. P., L. K. Rosenfeld, B. A. Grantham, Y. Shkedy, and J. Roughgarden. 2002. 599 Distributions of larval rockfishes Sebastes spp. across nearshore fronts in a coastal 600 upwelling region. Marine Ecology-Progress Series 242: 215-228.601 Brodeur, R. D., S. Ralston, R. L. Emmett, M. Trudel, T. D. Auth, and A. J. Phillips. 2006. Anomalous 602 pelagic nekton abundance, distribution, and apparent recruitment in the northern 603 California Current in 2004 and 2005. Geophysical Research Letters 33.604 Caley, M. J., M. H. Carr, M. A. Hixon, T. P. Hughes, G. P. Jones, and B. A. Menge. 1996. Recruitment 605 and the local dynamics of open marine populations. Annual Review of Ecology and 606 Systematics 27: 477-500.607 Carr, M. H., and D. C. Reed. 1993. Conceptual Issues Relevant to Marine Harvest Refuges - 608 Examples from Temperate Reef Fishes. Canadian Journal of Fisheries and Aquatic Sciences 609 50: 2019-2028.610 Carr, M. H., and C. Syms. 2006a. Chapter 15: Recruitment, pp. 411-427. In: The Ecology of Marine 611 Fishes. L.G. Allen, D.J. Pondella II, and M.H. Horn (eds.). University of California Press, 612 Berkeley, CA.613 ---. 2006b. Recruitment, p. 411-427. In L. G. Allen, D. J. Pondella and M. H. Horn [eds.], The Ecology 614 of Marine Fishes. University of California Press.615 Caselle, J. E., M. H. Carr, D. P. Malone, J. R. Wilson, and D. E. Wendt. 2010a. Can we predict 616 interannual and regional variation in delivery of pelagic juveniles to nearshore 617 populations of rockfishes (Genus Sebastes) using simple proxies of ocean conditions? 618 CalCOFI Report 51: 91-105.
Page 25 of 42
https://mc06.manuscriptcentral.com/cjfas-pubs
Canadian Journal of Fisheries and Aquatic Sciences
Draft
26
619 Caselle, J. E., B. P. Kinlan, and R. R. Warner. 2010b. Temporal and Spatial Scales of Influence on 620 Nearshore Fish Settlement in the Southern California Bight. Bulletin of Marine Science 86: 621 355-385.622 Chan, F. and others 2008. Emergence of anoxia in the California current large marine ecosystem. 623 Science 319: 920-920.624 Cowen, R. K., and S. Sponaugle. 2009. Larval Dispersal and Marine Population Connectivity. 625 Annual Review of Marine Science 1: 443-466.626 Cury, P., and C. Roy. 1989. Optimal environmental window and pelagic fish recruitment success in 627 upwelling areas. Canadian Journal of Fisheries and Aquatic Sciences 46: 670-680.628 Cushing, D. H. 1990. Plankton Production and Year-Class Strength in Fish Populations - an Update 629 of the Match Mismatch Hypothesis. Advances in Marine Biology 26: 249-293.630 D.F.O. 2007. State of the Pacific Ocean 2006. Ocean Status Report.631 Doherty, P., and T. Fowler. 1994. An empirical-test of recruitment limitation in a coral-reef fish. 632 Science 263: 935-939.633 Doherty, P. J., and D. M. Williams. 1988. The Replenishment of Coral-Reef Fish Populations. 634 Oceanography and Marine Biology 26: 487-551.635 Farrell, T. M., D. Bracher, and J. Roughgarden. 1991. Cross-Shelf Transport Causes Recruitment to 636 Intertidal Populations in Central California. Limnology and Oceanography 36: 279-288.637 Field, J. C., and S. Ralston. 2005. Spatial variability in rockfish (Sebastes spp.) recruitment events 638 in the California Current System. Canadian Journal of Fisheries and Aquatic Sciences 62: 639 2199-2210.640 Fogarty, M. J., and L. W. Botsford. 2007. Population Connectivity and Spatial Management of 641 Marine Fisheries. Oceanography 20: 112-123.642 Francis, M. P. 1994. Duration of Larval and Spawning Periods in Pagrus-Auratus (Sparidae) 643 Determined from Otolith Daily Increments. Environmental Biology of Fishes 39: 137-152.644 Gaines, S. D., B. Gaylord, and J. L. Largier. 2003. Avoiding current oversights in marine reserve 645 design. Ecological Applications 13: S32-S46.646 Gallagher, M. B. 2007. Growth rates and species composition of juvenile rockfish (Sebastes spp.) 647 in Oregon's nearshore and estuarine habitats. M.Sc. Oregon State University.648 Green, B. S., and R. Fisher. 2004. Temperature influences swimming speed, growth and larval 649 duration in coral reef fish larvae. Journal of Experimental Marine Biology and Ecology 650 299: 115-132.651 Haggarty, D. R., K. E. Lotterhos, and J. B. Shurin. 2017. Young-of-the-year recruitment does not 652 predict the abundance of older age classes in black rockfish in Barkley Sound, British 653 Columbia, Canada. Marine Ecology Progress Series 574: 113-126.654 Haggarty, D. R., S. J. D. Martell, and J. B. Shurin. 2016a. Lack of recreational fishing compliance 655 may compromise effectiveness of Rockfish Conservation Areas in British Columbia. 656 Canadian Journal of Fisheries and Aquatic Sciences 73: 1587-1598.657 Haggarty, D. R., J. B. Shurin, and K. L. Yamanaka. 2016b. Assessing population recovery inside 658 British Columbia's Rockfish Conservation Areas with a remotely operated vehicle. 659 Fisheries Research 183: 165-179.660 Hare, J. A., and R. K. Cowen. 1997. Size, growth, development, and survival of the planktonic 661 larvae of Pomatomus saltatrix (Pisces: Pomatomidae). Ecology 78: 2415-2431.662 Harley, C. D. G. and others 2006. The impacts of climate change in coastal marine systems. 663 Ecology Letters 9: 228-241.664 Hedgecock, D. 1994. Does Variance in Reproductive Success Limit Effective Population Sizes of 665 Marine Organisms. Genetics and Evolution of Aquatic Organisms: 122-134.
Page 26 of 42
https://mc06.manuscriptcentral.com/cjfas-pubs
Canadian Journal of Fisheries and Aquatic Sciences
Draft
27
666 Hickey, B. M., R. E. Thomson, H. Yih, and P. H. Leblond. 1991. Velocity and Temperature-667 Fluctuations in a Buoyancy-Driven Current Off Vancouver Island. Journal of Geophysical 668 Research-Oceans 96: 10507-10538.669 Hixon, M. A., and M. S. Webster. 2002. Density dependence in reef fish populations, pp.303-325. 670 In: Coral Reef Fishes: Dynamics and Diversity in a Complex Ecosystem. P.F. Sale (ed.). 671 Academic Press, San Diego, CA.672 Hjort, J. 1914. Fluctuations in the great fisheries of northern Europe viewed in the light of 673 biological674 research. Rapports et Proc`es-verbaux des R´eunions, Conseil International pour l’Exploration del 675 la Mer 20: 1-228.676 Houde, E. D. 1989. COMPARATIVE GROWTH, MORTALITY, AND ENERGETICS OF MARINE FISH 677 LARVAE - TEMPERATURE AND IMPLIED LATITUDINAL EFFECTS. Fishery Bulletin 87: 678 471-495.679 ---. 2009. Chapter 3. Recruitment variability, pp. 91-171. In: T. Jakobsen, M. Fogarty, B. Megrey 680 and E. Moksness (eds.). Reproductive biology of fishes: implications for assessment and 681 management, Wiley-Blackwell.682 Hyde, J. R., and R. D. Vetter. 2007. The origin, evolution, and diversification of rockfishes of the 683 genus Sebastes (Cuvier). Molecular Phylogenetics and Evolution 44: 790-811.684 Jenkins, G. P., and D. King. 2006. Variation in larval growth can predict the recruitment of a 685 temperate, seagrass-associated fish. Oecologia 147: 641-649.686 Kokita, T., and M. Omori. 1999. Long distance dispersal of larval and juvenile rockfish, Sebastes 687 thompsoni, with drifting seaweed in the Tohoku area, Northwest Pacific, estimated by 688 analysis of otolith microstructure. Bulletin of Marine Science 65: 105-118.689 Kosro, P. M., W. T. Peterson, B. M. Hickey, R. K. Shearman, and S. D. Pierce. 2006. Physical versus 690 biological spring transition: 2005. Geophysical Research Letters 33: -.691 Laidig, T. E., J. R. Chess, and D. F. Howard. 2007. Relationship between abundance of juvenile 692 rockfishes (Sebastes spp.) and environmental variables documented off northern 693 California and potential mechanisms for the covariation. Fishery Bulletin 105: 39-48.694 Laidig, T. E., and S. Ralston. 1995. The Potential Use of Otolith Characters in Identifying Larval 695 Rockfish (Sebastes Spp). Fishery Bulletin 93: 166-171.696 Laidig, T. E., S. Ralston, and J. R. Bence. 1991. Dynamics of Growth in the Early Life-History of 697 Shortbelly Rockfish Sebastes-Jordani. Fishery Bulletin 89: 611-621.698 Larson, R. J., W. H. Lenarz, and S. Ralston. 1994. The Distribution of Pelagic Juvenile Rockfish of 699 the Genus Sebastes in the Upwelling Region Off Central California. California Cooperative 700 Oceanic Fisheries Investigations Reports 35: 175-221.701 Lasker, R. 1975. Field Criteria for Survival of Anchovy Larvae - Relation between Inshore 702 Chlorophyll Maximum Layers and Successful 1st Feeding. Fishery Bulletin 73: 453-462.703 Leaman, B. M. 1991. Reproductive Styles and Life-History Variables Relative to Exploitation and 704 Management of Sebastes Stocks. Environmental Biology of Fishes 30: 253-271.705 Leggett, W. C., and E. Deblois. 1994. Recruitment in Marine Fishes - Is It Regulated by Starvation 706 and Predation in the Egg and Larval Stages. Netherlands Journal of Sea Research 32: 119-707 134.708 Lenarz, W. H., and T. W. Echeverria. 1986. Comparison of Visceral Fat and Gonadal Fat Volumes of 709 Yellowtail Rockfish, Sebastes-Flavidus, during a Normal Year and a Year of El-Nino 710 Conditions. Fishery Bulletin 84: 743-745.711 Lenarz, W. H., D. A. Ventresca, W. M. Graham, F. B. Schwing, and F. Chavez. 1995. Explorations of 712 El Nino events and associated biological population dynamics off central California. 713 California Cooperative Oceanic Fisheries Investigations Reports 36: 106-119.
Page 27 of 42
https://mc06.manuscriptcentral.com/cjfas-pubs
Canadian Journal of Fisheries and Aquatic Sciences
Draft
28
714 Lipcius, R. N. and others 2008. Importance of metapopulation connectivity to restocking and 715 restoration of marine species. Reviews in Fisheries Science 16: 101-110.716 Lotterhos, K. E., and R. W. Markel. 2012. Oceanographic drivers of offspring abundance may 717 increase or decrease reproductive variance in a temperate marine fish. Molecular Ecology 718 21: 5009-5026.719 Love, M. S., M. M. Yoklavich, and L. Thorsteinson. 2002. The rockfishes of the Northeast Pacific. 720 University of California Press.721 Mac Nally, R. 2002. Multiple regression and inference in ecology and conservation biology: 722 further comments on identifying important predictor variables. Biodiversity and 723 Conservation 11: 1397-1401.724 Mac Nally, R., and C. J. Walsh. 2004. Hierarchical partitioning public-domain software. 725 Biodiversity and Conservation 13: 659-660.726 Mace, A. J., and S. G. Morgan. 2006. Biological and physical coupling in the lee of a small headland: 727 contrasting transport mechanisms for crab larvae in an upwelling region. Marine Ecology-728 Progress Series 324: 185-196.729 Mackas, D. L., W. T. Peterson, M. D. Ohman, and B. E. Lavaniegos. 2006. Zooplankton anomalies in 730 the California Current system before and during the warm ocean conditions of 2005. 731 Geophysical Research Letters 33: -.732 Markel, R. W., K. E. Lotterhos, and C. L. K. Robinson. 2017. Temporal variability in the 733 environmental and geographic predictors of spatial-recruitment in nearshore rockfishes. 734 Marine Ecology Progress Series 574: 97-111.735 Markel, R. W., and J. B. Shurin. 2015. Indirect effects of sea otters on rockfish (Sebastes spp.) in 736 giant kelp forests. Ecology 96: 2877-2890.737 Mason, J. 1998. Declining rockfish lengths in the Monterey Bay, California, recreational fishery, 738 1959−94. Marine Fisheries Review 60: 15−28.739 Mearns, A. J., M. J. Allen, M. D. Moore, and M. J. Sherwood. 1980. Distribution, abundance, and 740 recruitment of soft bottom rockfishes (Scorpaenidae: Sebastes) on the southern California 741 mainland shelf. California Cooperative Oceanic Fisheries Investigations Reports 21: 742 180−190.743 Miller, J. A., and A. L. Shanks. 2004. Evidence for limited larval dispersal in black rockfish 744 (Sebastes melanops): implications for population structure and marine-reserve design. 745 Canadian Journal of Fisheries and Aquatic Sciences 61: 1723-1735.746 Moser, H. G., and G. W. Boehlert. 1991. Ecology of Pelagic Larvae and Juveniles of the Genus 747 Sebastes. Environmental Biology of Fishes 30: 203-224.748 Munk, K. M. 2001. Maximum ages of groundfishes in waters off Alaska and British Columbia and 749 considerations of age determination. Alaska Fishery Research Bulletin 8.750 Neuheimer, A. B., R. E. Thresher, J. M. Lyle, and J. M. Semmens. 2011. Tolerance limit for fish 751 growth exceeded by warming waters. Nat. Clim. Chang. 1: 110-113.752 Newell, C. L., and T. J. Cowles. 2006. Unusual gray whale Eschrichtius robustus feeding in the 753 summer of 2005 off the central Oregon Coast. Geophysical Research Letters 33.754 Otterlei, E., G. Nyhammer, A. Folkvord, and S. O. Stefansson. 1999. Temperature- and size-755 dependent growth of larval and early juvenile Atlantic cod (Gadus morhua): a comparative 756 study of Norwegian coastal cod and northeast Arctic cod. Canadian Journal of Fisheries 757 and Aquatic Sciences 56: 2099-2111.758 Parker, S. J. and others 2000. Management of Pacific rockfish. Fisheries 25: 22-30.759 Pasten, G. P., S. Katayama, and M. Omori. 2003. Timing of parturition, planktonic duration, and 760 settlement patterns of the black rockfish, Sebastes inermis. Environmental Biology of 761 Fishes 68: 229-239.
Page 28 of 42
https://mc06.manuscriptcentral.com/cjfas-pubs
Canadian Journal of Fisheries and Aquatic Sciences
Draft
29
762 Pepin, P. 1991. Effect of Temperature and Size on Development, Mortality, and Survival Rates of 763 the Pelagic Early Life-History Stages of Marine Fish. Canadian Journal of Fisheries and 764 Aquatic Sciences 48: 503-518.765 Pepin, P., and R. A. Myers. 1991. Significance of Egg and Larval Size to Recruitment Variability of 766 Temperate Marine Fish. Canadian Journal of Fisheries and Aquatic Sciences 48: 1820-767 1828.768 Plaza, G., S. Katayama, and M. Omori. 2001. Otolith microstructure of the black rockfish, Sebastes 769 inermis. Marine Biology 139: 797-805.770 Ralston, S., E. B. Brothers, D. A. Roberts, and K. M. Sakuma. 1996. Accuracy of age estimates for 771 larval Sebastes jordani. Fishery Bulletin 94: 89-97.772 Ralston, S., and D. F. Howard. 1995. On the Development of Year-Class Strength and Cohort 773 Variability in 2 Northern California Rockfishes. Fishery Bulletin 93: 710-720.774 Rau, G. H., S. Ralston, J. R. Southon, and F. P. Chavez. 2001. Upwelling and the condition and diet of 775 juvenile rockfish: A study using C-14, C-13, and N-15 natural abundances. Limnology and 776 Oceanography 46: 1565-1570.777 Roughgarden, J., S. Gaines, and H. Possingham. 1988. Recruitment dynamics in complex life-cycles. 778 Science 241: 1460-1466.779 Roughgarden, J., Y. Iwasa, and C. Baxter. 1985. Demographic-Theory for an Open Marine 780 Population with Space-Limited Recruitment. Ecology 66: 54-67.781 Sale, P. F. 1977. Maintenance of High Diversity in Coral-Reef Fish Communities. American 782 Naturalist 111: 337-359.783 Schwing, F. B., N. A. Bond, S. J. Bograd, T. Mitchell, M. A. Alexander, and N. Mantua. 2006. Delayed 784 coastal upwelling along the US West Coast in 2005: A historical perspective. Geophysical 785 Research Letters 33.786 Secor, D. H. 2007. The year-class phenomenon and the storage effect in marine fishes. Journal of 787 Sea Research 57: 91-103.788 Selkoe, K. A., S. D. Gaines, J. E. Caselle, and R. R. Warner. 2006. Current shifts and kin aggregation 789 explain genetic patchiness in fish recruits. Ecology 87: 3082-3094.790 Shanks, A. L. 2009. Pelagic Larval Duration and Dispersal Distance Revisited. Biological Bulletin 791 216: 373-385.792 Shanks, A. L., and L. Brink. 2005. Upwelling, downwelling, and cross-shelf transport of bivalve 793 larvae: test of a hypothesis. Marine Ecology-Progress Series 302: 1-12.794 Shanks, A. L., and G. L. Eckert. 2005. Population persistence of California Current fishes and 795 benthic crustaceans: A marine drift paradox. Ecological Monographs 75: 505-524.796 Sponaugle, S., and R. K. Cowen. 1997. Early life history traits and recruitment patterns of 797 Caribbean wrasses (Labridae). Ecological Monographs 67: 177-202.798 Sydeman, W. J. and others 2006. Planktivorous auklet Ptychoramphus aleuticus responses to 799 ocean climate, 2005: Unusual atmospheric blocking? Geophysical Research Letters 33.800 Thomas, A. C., and P. Brickley. 2006. Satellite measurements of chlorophyll distribution during 801 spring 2005 in the California Current. Geophysical Research Letters 33: -.802 Thomson, R. E., and D. M. Ware. 1996. A current velocity index of ocean variability. Journal of 803 Geophysical Research-Oceans 101: 14297-14310.804 Vigliola, L., M. Harmelin-Vivien, and M. G. Meekan. 2000. Comparison of techniques of back-805 calculation of growth and settlement marks from the otoliths of three species of Diplodus 806 from the Mediterranean Sea. Canadian Journal of Fisheries and Aquatic Sciences 57: 1291-807 1299.808 Ware, D. M., and R. E. Thomson. 2005. Bottom-up ecosystem trophic dynamics determine fish 809 production in the Northeast Pacific. Science 308: 1280-1284.
Page 29 of 42
https://mc06.manuscriptcentral.com/cjfas-pubs
Canadian Journal of Fisheries and Aquatic Sciences
Draft
30
810 Warner, R. R., and P. L. Chesson. 1985. Coexistence Mediated by Recruitment Fluctuations - a 811 Field Guide to the Storage Effect. American Naturalist 125: 769-787.812 Warner, R. R., and R. K. Cowen. 2002. Local retention of production in marine populations: 813 Evidence, mechanisms, and consequences. Bulletin of Marine Science 70: 245-249.814 Weise, M. J., D. P. Costa, and R. M. Kudela. 2006. Movement and diving behavior of male California 815 sea lion (Zalophus californianus) during anomalous oceanographic conditions of 2005 816 compared to those of 2004. Geophysical Research Letters 33.817 Williams, G. D., P. S. Levin, and W. A. Palsson. 2010. Rockfish in Puget Sound: An ecological history 818 of exploitation. Marine Policy 34: 1010-1020.819 Wilson, D. T., and M. I. Mccormick. 1997. Spatial and temporal validation of settlement-marks in 820 the otoliths of tropical reef fishes. Marine Ecology-Progress Series 153: 259-271.821 ---. 1999. Microstructure of settlement-marks in the otoliths of tropical reef fishes. Marine 822 Biology 134: 29-41.823 Wilson, J. A., L. Vigliola, and M. G. Meekan. 2009. The back-calculation of size and growth from 824 otoliths: Validation and comparison of models at an individual level. Journal of 825 Experimental Marine Biology and Ecology 368: 9-21.826 Wilson, J. R., B. R. Broitman, J. E. Caselle, and D. E. Wendt. 2008. Recruitment of coastal fishes and 827 oceanographic variability in central California. Estuarine Coastal and Shelf Science 79: 828 483-490.829 Woodbury, D. 1999. Reduction of growth in otoliths of widow and yellowtail rockfish (Sebastes 830 entomelas and S-flavidus) during the 1983 El Nino. Fishery Bulletin 97: 680-689.831 Woodbury, D., and S. Ralston. 1991. Interannual variation in growth-rates and back-calculated 832 birth-date distributios of pelagic juvenile rockfishes (Sebastes spp) of the central 833 California coast. Fishery Bulletin 89: 523-533.834 Yamanaka, K. L., and G. Logan. 2010. Developing British Columbia’s inshore rockfish conservation 835 strategy. Marine and Coastal Fisheries: Dynamics, Management, and Ecosystem Science 2: 836 28-46.837 Yoklavich, M. M., and G. W. Boehlert. 1987. Daily Growth Increments in Otoliths of Juvenile Black 838 Rockfish, Sebastes-Melanops - an Evaluation of Autoradiography as a New Method of 839 Validation. Fishery Bulletin 85: 826-832.840841
Page 30 of 42
https://mc06.manuscriptcentral.com/cjfas-pubs
Canadian Journal of Fisheries and Aquatic Sciences
Draft
31
843 Table 1. Comparison of early life history attributes of Black and CQB Rockfishes between 2005 and
844 2006.
845
A. Black Rockfish
2005 (n = 27) 2006 (n = 40) T value P>T
Parturition date 17-Feb ± 2.5 d 20-Feb ± 1.8 d 0.78 0.4404
Settlement date 25-Apr ± 3 d 7-May ± 1.8 d 3.25 0.0022
Pelagic duration 67 d ± 1.7 d 76 d ± 1.4 d 4.04 0.0002
Size-at-settlement 19.85 mm ± 0.73 19.95 mm ± 0.54 0.11 0.9117
B. CQB Rockfish
2005 (n = 20) 2006 (n = 19) T value P>T
Parturition 16-Apr ± 4.7 d 19-Mar ± 3.7 d 5.70 <0.0001
Settlement 6-Jun ± 3.4 d 22-May ± 4 d 2.89 0.0065
Pelagic duration 51 d ± 2.6 d, 63 d ± 2.7 d 3.37 0.0018
Size-at-settlement 11.83 mm ± 0.9 14.09 mm ± 0.90 2.17 0.0355
846
Page 31 of 42
https://mc06.manuscriptcentral.com/cjfas-pubs
Canadian Journal of Fisheries and Aquatic Sciences
Draft
32
848 Figure Legends
849
850 Figure 1. A conceptual model depicting the direct (solid lines) and indirect (dashed lines) effects of
851 coastal upwelling on pelagic larval fish. By regulating sea surface temperature (SST) and primary
852 productivity (Chl-a) coastal upwelling has indirect negative or positive effects on larval growth rates,
853 depending on which factor is most limiting. As a result of size-specific predation rates, pre-settlement
854 growth rates directly and indirectly impact pelagic-stage cumulative mortality rates, and therefore
855 settlement rates. By regulating cross-shelf flow regimes coastal upwelling increases or decreases
856 pelagic durations, and therefore settlement rates, by inhibiting or facilitating movement of larvae to
857 nearshore settlement habitats and adult populations.
858 Figure 2. Annual recruitment (rockfish per SMURF; mean ± SE) in August between 2005 and 2010.
859 The number of SMURFs deployed varied annually: 2005 (n=16), 2006-2009 (n=30), 2010 (n=6).
860 Figure 3. Comparison of Black Rockfish (n = 68) and CQB Rockfish (n = 42) otolith daily growth
861 increment width and variance (mean ± SE) corresponding to the 20 days preceding and following
862 increments designated as the day on which settlement occurred.
863 Figure 4. Cohort-specific oceanographic conditions experienced by pre-settlement Black rockfish
864 (2005, n = 27, 2006, n = 39) and CQB Rockfishes (2005, n = 22, 2006, n = 19). Thick lines represent
865 daily averages of oceanographic metrics corresponding to the 60 days (Black rockfish) and 40 days
866 (CQB Rockfish) prior to settlement of individuals comprising each cohort. Thin lines represent 95%
867 confidence intervals around daily means.
868 Figure 5. Black and CQB Rockfish parturition and settlement intervals (defined as the 1st and 3rd
869 quartiles of date distributions), and mean pelagic durations in 2005 and 2006 in relation to upwelling
870 index values and sea surface temperatures (7-day moving averages), and chlorophyll-a levels (11-day
871 moving averages). Thin gray lines represent 95% confidence intervals around daily mean values
872 between 1977 and 2010.
Page 32 of 42
https://mc06.manuscriptcentral.com/cjfas-pubs
Canadian Journal of Fisheries and Aquatic Sciences
Draft
33
873 Figure 6. Growth rates of Black and CQB Rockfishes in 2005 and 2006. Growth curves (A and B) are
874 logistic growth models fitted to back-calculated growth trajectories of individuals comprising each
875 cohort. Length-at-age relationships (C and D) represent length (total length) and age (days) at capture.
876 Figure 7. Longitudinal growth profiles of Black and CQB Rockfishes based on mean otolith daily
877 growth increment width (solid lines, left y-axis) and back-calculated (Modified-Fry model) length-at-
878 age (dashed lines, right y-axis). Daily means (± SE) were calculated by centering individual growth
879 profiles on settlement increments/day (vertical lines). Settlement dates and pelagic durations are set to
880 annual means of each cohort.
881 Figure 8. Effects of sea surface temperature (SST), chlorophyll-a (Chl-a), and upwelling (Upwelling
882 Index) on Black rockfish pre-settlement growth (A and B) and pelagic duration (C and D). Values of
883 growth, SST, and Chl-a are averages for the 60 days following parturition. Values of upwelling are
884 averages for the 30 days prior to settlement.
885 Figure 9. Effects of sea surface temperature (SST), chlorophyll-a (Chl-a), and upwelling (Upwelling
886 Index) on CQB Rockfish pre-settlement growth (A and B) and pelagic duration (C and D). Values of
887 growth, SST, and Chl-a are averages for the 40 days following parturition. Values of upwelling are
888 averages for the 30 days prior to settlement.
Page 33 of 42
https://mc06.manuscriptcentral.com/cjfas-pubs
Canadian Journal of Fisheries and Aquatic Sciences
Draft
34
890 Figure 1
891
SST
Chl-a
CoastalUpwelling
Pre-settlementgrowth rates
Pelagic durationCumulative
mortality rates
Settlement rates
+
-
+
-
- +/-
+/-
+
-
-
Page 34 of 42
https://mc06.manuscriptcentral.com/cjfas-pubs
Canadian Journal of Fisheries and Aquatic Sciences
Draft
35
893 Figure 2
894
895
8962005 2006 2007 2008 2009 2010
0
5
10
15R
ecru
itmen
t(fis
h/S
MU
RF)
Black rockfishCQB rockfish
Page 35 of 42
https://mc06.manuscriptcentral.com/cjfas-pubs
Canadian Journal of Fisheries and Aquatic Sciences
Draft
36
898 Figure 3
899
4
6
8
10
12
14
16Black rockfish
A.
Incr
emen
twid
th(u
m)
copper$day
CQB rockfish
B.
-20 -10 0 10 20
0
2
4
6
8C.
Var
ianc
e
-20 -10 0 10 20
D.
Days (increments)
Page 36 of 42
https://mc06.manuscriptcentral.com/cjfas-pubs
Canadian Journal of Fisheries and Aquatic Sciences
Draft
37
901 Figure 4
902
-80
-60
-40
-20
0
20
40
days.blro.pre
blro
.05.
uw.m
ean
days.blro.pre
blro
.06.
uw.m
ean
Upw
ellin
gIn
dex
Black rockfish
A.
days.coro.pre
coro
.05.
uw.m
ean
days.coro.pre
coro
.06.
uw.m
ean
CQB rockfish
B.
7
8
9
10
11
12
13
days.blro.pre
blro
.05.
sst.m
ean
days.blro.pre
blro
.06.
sst.m
ean
SS
T(C
)
20052006
C.
days.coro.pre
coro
.05.
sst.m
ean
days.coro.pre
coro
.06.
sst.m
ean
D.
0
2
4
6
8
days.blro.pre
blro
.05.
chla
.mea
n
-60 -50 -40 -30 -20 -10 0
days.blro.pre
blro
.06.
chla
.mea
nC
hla
(mg
m-3
)
E.
days.coro.pre
coro
.05.
chl.m
ean
-40 -30 -20 -10 0
days.coro.pre
coro
.06.
chl.m
ean
F.
Days preceding settlement
903
Page 37 of 42
https://mc06.manuscriptcentral.com/cjfas-pubs
Canadian Journal of Fisheries and Aquatic Sciences
Draft
38
904 Figure 5
905
906
-150
-100
-50
0
50
day
uw.ra
w.0
5
A.
67 1.7 dBlackCQB
51 2.6 d
2005
Upw
ellin
gIn
dex
day
uw.ra
w.0
6
76 1.4 d
63 2.7 dB.
2006
7
8
9
10
11
12
13
day
sst.r
aw.0
5
C.
SS
T(C
)
day
sst.r
aw.0
6
D.
2
4
6
8
10
day.chla
chla
.05
Jan Feb Mar Apr May June
Chl
-a(m
gm
-3)
E.
day.chla
chla
.06
Jan Feb Mar Apr May June
F.
Month
907
Page 38 of 42
https://mc06.manuscriptcentral.com/cjfas-pubs
Canadian Journal of Fisheries and Aquatic Sciences
Draft
39
909 Figure 6
910
Page 39 of 42
https://mc06.manuscriptcentral.com/cjfas-pubs
Canadian Journal of Fisheries and Aquatic Sciences
Draft
40
912 Figure 7
913
914
0
5
10
15
0 30 60 90 120 150
A. Black rockfish
67 1.7 d
76 1.4 d
25-Apr 3 d 7-May 1.8 d
20052006
0
20
40
60
80
100
120
19.85 0.7mm 19.95 0.5mm
0
5
10
15
0 30 60 90 120 150
20052006
B. CQB rockfish
51 2.6 d
63 2.7 d 6-June 3.4 d
22-May 4 d
0
20
40
60
80
100
14.09 0.9 mm11.83 0.9 mm
Days (increments)
Incr
emen
twid
th(u
m)
Bac
k-ca
lcul
ated
tota
llen
gth
(mm
)
Page 40 of 42
https://mc06.manuscriptcentral.com/cjfas-pubs
Canadian Journal of Fisheries and Aquatic Sciences
Draft
41
916 Figure 8
917
7.5 8.0 8.5 9.0 9.5 10.0
2.5
3.0
3.5
4.0
4.5
5.0
sst.pre.lim
grow
th.p
re.li
m
SST (degrees C)
Incr
emen
twid
th(u
m)
Black rockfish
A. R2 0.24
2.0 2.5 3.0 3.5 4.0 4.5 5.0
2.5
3.0
3.5
4.0
4.5
5.0
chla.pre.lim
grow
th.p
re.li
m
Chl-a (mg m-3)
B. 20052006
2.5 3.0 3.5 4.0 4.5 5.0
60
65
70
75
80
85
90
95
growth.pre.lim
pd
Increment width (um)
Pel
agic
dura
tion
(d)
C.
R2 0.30
-40 -20 0 20 40
60
65
70
75
80
85
90
95
uw30
pd
Upwelling (m3 s-1 100m-1)
D.
R2 0.20
Page 41 of 42
https://mc06.manuscriptcentral.com/cjfas-pubs
Canadian Journal of Fisheries and Aquatic Sciences
Draft
42
919 Figure 9
920
7 8 9 10 11 12 13
1.5
2.0
2.5
3.0
3.5
sst.pre.lim
grow
th.p
re.li
m
SST (degrees C)
CQB rockfish
Incr
emen
twid
th(u
m)
A.R2 0.34
2 4 6 8
1.5
2.0
2.5
3.0
3.5
chla.pre.lim
grow
th.p
re.li
m
Chl-a (mg m-3)
B. 20052006
1.5 2.0 2.5 3.0 3.5 4.0
30
40
50
60
70
80
90
growth.pre.lim
pd
Increment width (um)
Pel
agic
dura
tion
(d)
C.
R2 0.25
-40 -20 0 20 40
30
40
50
60
70
80
90
uw30
pd
Upwelling (m3 s-1 100m-1)
D.
R2 0.18
Page 42 of 42
https://mc06.manuscriptcentral.com/cjfas-pubs
Canadian Journal of Fisheries and Aquatic Sciences