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PFRP
black-footed albatross
modelling workshop
http://www.soest.hawaii.edu/PFRP/wiki/tiki-index.php?page=
Albatross+Modeling+Workshop
Background
•Black-footed albatross Phoebastrianigripes
•Breed on north-western Hawaiian islands
–Genetically distinct population on Torishima island
•About 60000 breeding pairs in Hawaiian
population
•Conservation status
–Endangered (IUCN)
–Status review (US ESA)
2001 PFRP Protected Species
Modeling Workshop
•“Development of integrated statistical
models for Hawaiian albatross populations
is feasible and could be started at any time”
•Priority research area for 2002 RFP
•Two projects funded
Purpose of modelling workshop
•Review results of the PFRP-funded
projects,
•Compare these results to other population
assessments,
•Identify problems in model development
and application, and
•Suggest future directions for model
development.
.
Black-footed Albatross
Satellite tracking data –limited # birds and time period
Fledgling albatrosses (red dots) tracked from Midway Atoll
Trajectories vary among islands
Kure
0
200
400
600
800
1,000
1,200
1,400 1950
1960
1970
1980
1990
2000
FFS
0
1,000
2,000
3,000
4,000
5,000
6,000
7,000 1950
1960
1970
1980
1990
2000
2010
Midway
0
5,000
10,000
15,000
20,000
25,000 1950
1960
1970
1980
1990
2000
2010
Laysan
0
5,000
10,000
15,000
20,000
25,000
30,000
35,000
40,000
45,000 1950
1960
1970
1980
1990
2000
2010
Lisianski
0
1,000
2,000
3,000
4,000
5,000
6,000 1950
1960
1970
1980
1990
2000
2010
Pearl and Hermes Reef
0
1,000
2,000
3,000
4,000
5,000
6,000
7,000
8,000
9,000 1950
1960
1970
1980
1990
2000
Current threats
•At sea effects
–Longline fishing
–Pollutants
•Plastic ingestion
•Lost and discarded fishing gear
•Breeding colony effects
–Invasive species
•predators, plants, invertebrates, diseases
–Pollutants
–Climate change
Modelling
0,5
0,6
0,7
0,8
0,91
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
Adult Survival
Adult Survival
Probability
Probability
Year
Year
Survival analysis
Survival analysis
Veran et al. 2007
Veran et al. 2007
Significantly correlated with fishing effort variable
Significantly correlated with fishing effort variable
--22ndndPC of PCA (mostly north Pacific swordfish catch)
PC of PCA (mostly north Pacific swordfish catch)
--effectively only 5
effectively only 5-- 6 data points through 2002
6 data points through 2002
Compare survival rate with other species
Compare survival rate with other species
•• Veran
Veran&
& Lebreton
Lebretonin prep
in prep
••Low estimate compared with other Albatross species
Low estimate compared with other Albatross species
(estimates possibly affected by heterogeneity
(estimates possibly affected by heterogeneity……
and
andbyby-- catch)
catch)
••Wide confidence interval (price to pay for heterogeneity)
Wide confidence interval (price to pay for heterogeneity)
Integrated analysis (Veran)
Integrated analysis 2
•Maunder, Hoyle, Alvarez-Flores
–2 separate models
•Fitting to all available data
–Counts of adults and fledglings
–Survival rate estimates
–Breeding success estimates
–Bycatch estimates
•Preliminary results so far
Only preliminary results so far
•Fit only to drift gillnet and Hawaiian longline data
(other longline data not yet included)
•Bird count, albatross distribution estimates,
model structure and parameter values being
revised
•No estimates of uncertainty
•Final results likely to be very different
Integrated analysis
preliminary results –not realistic
Total bycatch (longline + driftnet)
preliminary results –not realistic
0
2,000
4,000
6,000
8,000
10,000
12,000
14,000 1950
1955
1960
1965
1970
1975
1980
1985
1990
1995
2000
2005
Year
Bycatch
1(GOA)
2(BSAI)
3(Cal)
4(HWD)
5(HWS)
6(FLLS)
7(FLLD)
8(LDJ)
9(SDJ)
10(SDT)
11(SDK)
Total
Data availability
•Finding: Data availability and legal
constraints impede research and model
development.
•Recommendation: Legal constraints need
to be resolved within agencies and
between governments. Metadata inventory
could be hosted on the NPAWG website
Data interpretation and analysis
•Finding: Spatial and temporal overlap
between fishing effort and bird distribution
is critical to estimate bycatch and
understand fishery impacts.
•Recommendation: Develop uniform means
to characterize longline fishing depth by
identifying usable proxies. Attempt to
access bird tracking results from TOPP
and other sources.
Data storage and dissemination
•Finding: The existing institutions do not
provide a stable means to store and
update albatross band resighting data.
•Recommendation: Continue to develop the
USGS/BBL database. Consolidate existing
ad hoc research data collections.
Information needs for FWS
Listing
•Finding: Change in population size is
a critical piece of information on
which the decision to list may rest.
•Recommendation: More information
on “walkers”, changes in age of first
reproduction, changes in survival by
age, will improve estimates of
population size.
Data collection on-colony
•Finding: It may be possible to collect additional data
without compromising current protocols.
•Recommendations:
–Clarifying which parameter(s) of interest are needed
to monitor population change would facilitate the
design of data collection protocols. Additional
statistical consultation may help to optimize banding
efforts among islands and age classes.
–PIT tag pilot study, collect and archive feathers/egg
shells, collect and analyzemating pair data on
known-age plots.