J~1)O

SEMI-ANNUAL PROGRESS REPORT FOR THE

MULTIPLANT IMPACT STUDY OF THE HUDSON RIVER ESTUARY

MAY NOVEMBER 1974

FEBRUARY ;197

Prepared for

CONSOLIDATED EDISON COMPANY OF NEW YORK, INC. 4 Irving PIlace

New York, New York 10003

Prepared by

TEXAS INSTRUMENTS INCORPORATED Ecological Services

P.O. Box 5621 Dallas, Texas 75222

Copyri ght

Texas Instruments Incorporated Dallas, Texas February 1975

___ 111070121 750310 PDR ADOCK 05000266 _________ ____DR_ V o- csg'

TABLE OF CONTENTS

Chapter Title Page

I. Introduction I-l

II. Direct Impact Assessment II-l

A. Entrainment Il

B. Impingement 11-3

Ill. Stock Assessment III

A. Historical Data Base Analysis III-1

B. Vulnerability Matrix 111-4

C. Compensation- 11-18

IV. Literature Cited IV-l

ser'vice group

TABLES

Title

List of Hudson River Power Plants Considered in the Multiplant Impact Assessment.

Description and Status of 1974 Ichthyoplankton Operations Field Programs.

Description and Status of 1974 Ichthyoplankton Operations Laboratory Programs.

Description and Status of 1974 Fisheries Operations Field and Laboratory Programs.

Number of white perch, striped bass and Atlantic tomcod Marked and Recaptured from January through August 1974

Description and Status of 1974 Survey, August - October 1974.

Lower Estuary

ii seio~; ~c~p

Table Page

111-7

III-!O

111-12

111-15

111-17

I. INTRODUCTION

The Multiplant Impact Study of the .Hudson River Estuary,

begun in January 1974, represents consolidation and integration of ongoing

objectives relative to power plant impact on the river. The program was

designed to inventory selected biological and chemical parameters and

assess the combined ecological impact of five electrical generating stations

(Table 1) on the fishery resources of the estuary.

The purpose of the multiplant impact study is to provide

the field sampling and data analyses necessary to assess individual plant

and combined plant impact. The overall program is based on the study of key

fish Populations Ipeua, White peh, At],,ntic to,,,du using standard

techniques for the study of fish populations. To accomplish the purpose,

two overall objectives with specific tasks are underway.

Objective I. Direct Impact Assessment

" the estimation of immediate power plant impact on the key

fish population expressed as percent population reduction

due to entrainment and impingement at each plant site

Task A. Entrainment and impingement monitoring at

plant intakes

Task B. Near-field transect s:ampling to determine

distribution and abundance in the immediate

I-i services group

TABLE 1. List of Hudson River Power Plants Considered in the Multiplant Impact Assessment. 1

PLANT SITE

RIVER OPERATING MILE UTILITY

UNIT NUMBER

Bowline 37 Orange & Fossil Rockland

Orange & Fossil Rockland

Lovett 41 Orange,& 1 Fossil Rockland

Orange & 2 Fossil Rockland

Orange & 3 Fossil Rockland

Orange & 4 Fossil Rockland

Orange & 5 Fossil Rockland

Indian Point 42 Con Edison Nuclear

Con Edison 2 Nuclear

Con Edison 3 Nuclear •Roseton 65 Central 1 Fossil

Hudson

Central 2 Fossil Hudson

Danskammer 66 Central 1 Fossil Hudson

Central 2 Fossil Hudson

Central 3 Fossil Hudson

Central 4 Fossil Hudson

1 Report of Member Electric Corporation of the New Empire State Electric Energy Research Corporation VIII, Section 149-B, of the Public Service Law.

2 Predicted Start of Operations.

STYPECAPACITY

We

600

600

19

20

68

195

202

265

873

1033

600

600

66

1954

1959

1967

York Power Pool and the . Persuant to Article

I -2 - _ _ _

START OF OPERATIONS

1972

1974

1949

1951

1955

1966

1969

1962

1973

1975

19752

1974

1951

vicinity of each plant

Task C. Estimation of standing crops of the entire

river populations for all available life

stages of the key species

Objective II. Stock Assessment

.. the analysis of the status of the fishery resources-.of

the Hudson River based on the historical and developing

data base

Task A. Analysis of the historical data based

(including gear selectivit, studies)

Task B. Far-field sampling studies (ichthyoplankton

survey, shoal survey, beach seine survey,

axial trawl survey, lower estuary survey,

and water chemistry)

Task C. Description of the vulnerability matrix

TaskD. Evaluation of compensatory mechanisms operating

within the fish populations

This semi-annual report, prepared for Consolidated Edison

Company of New York, Incorporated and the Inter-Utility Coordinating

Committee describes the field sampling and data evaluation for the multi-

1-3 services group

plant impact study being conducted by Texas Instruments Incorporated. The

current status of the 1974 program is reviewed. The Mu]ltiplant Annual Report

is scheduled for completion in spring, 1975.

1-4 services giroup

II. DIRECT IMPACT ASSESS1ENT

A. Entrainment

Direct impact of entrainment on the-key fish species (pri

marily striped bass) will be evaluated based on regional density• e-,timates,

near-fie-ld density estimates, intake densfty estimates and pumping rates for

the individual power pl-ants. Major emphasis will be placed on 1973 with

only preliminary conclusions for 1974 appearing in the annual report

(spring, 1975). Estimates made using near-field transect data and intake

ichthyoplankton densities for 1973 will be based on data presently available

from Lawler, Matusky, and Skelly (LMS) and New York University (NYU).

The 1974 direct impact of entrainment is being estimated from

regional densities and pumping rates. Transect and intake densities for

1974 will. not be available from LMS. and NYU in time to utilize this data to

make estimates for inclusion in the 1974 Multiplant Annual Report.

An estimate of entrainment at each power plant for both the

1973 and 1974 larval seasons is being calculated for each of the key species,

with major emphasis on striped bass. From these estimates, an assessment of

entrainment direct impact is being calculated and will be expressed as

"percent population reduction" at each plant individually and for all plants

combined.

Entrainment estimates for each plant are being calculated by

three methods for 1973; however, only one is being used for a 1974 estimate

I 1-1 services groupservices agroklp11-1

due to the unavailability of 1974 near-field,.transect and intake sampling

data. -These data should become available in early 1975 and will be included

in a later report. The three methods being used to calculate entrainment

estimates by available life stage for each-of the key species are:

1) Regional river density estimates calculated from TI ichthyo

plankton sampling data will be averaged. A weighted average

of the mean river densities will be used to generate a density

estimate for a."plant river region" (an area 6.5 miles above and

below each plant site). The depth strata will. be averaged on

the basis of river morphometry in the area of each plant. An

estimate of thenumber of eggs and; larvae .entrained at each

pl ant 1wiii be -computIed by muli plying the, 'plant river region'

density by the amount of water pumped by the individual plant.

2) Bi-weekly near-field transect data collected by:LMS and NYU

are being averaged to generate. a "plant river region" density

estimate for each plant. Again, an estimate of.the number of

eggs and larvae entrained.at each plant will be computed by

multiplying the "plantriver region" ,density by the amount

of water pumped.

3) Estimates of actual egg. and larval -densities in the plant

intakes are being calculated and will be combined with the

volume pumped to generate an estimate .of entrainment.

11-2 ~o

An estimate of the impingement dirt. i w hl -P.Dinpmen dir,!!t h -ppIprl-f.

for each of the key species (striped bass, white perch and Atlantic tomcod).

Utilizing available data, separate estimates will be made for each power

plant for the following three time periods: January-June, 1973; July-December,

1973; and January-June,. 1974.

Impingement at power plants other than Indian Point will be

estimated utilizing LMS impingement sampling data. Ratio estimates will be

calculated utilizing the number of fish impinged and volumes of water pumped

per sample-day for three month intervals. At Indian Point, impingement is

monitored on a daily basis so actual counts are available.

Standing crop estimates for the three key species will be

calculated for each six month period utilizing TI fisheries catch per unit

services group11-3

B. Imjpingement

The direct impact assessment of impingement at the individual

power plants will utilize data from January 1973 through June 1974. Estimates

of the latter part of 1974 will not be made in the 1974 Multiplant Annual

Report- because mark-recapture estimates of young-of-the-year populations

will not be available until after the spring 1975 recapture period and will

be included in a later report. Estimates of direct impact for the

power plant at which impingement is infrequently sampled will be based on

impingement rates per unit flow in conjunction with the plant pumping

schedules.

effort and mark-recapture data. Calculated impingement estimates will be

compared with corresponding standing crop estimates.

STATUS

a. Progress on direct impact assessment for 1974 is proceeding

on schedule.

b. The 1974 Texas Instruments ichthyoplankton samples are being

picked and analyzed on a temporally selective priority basis,

so that standing crops can be estimated for the different

times of the year. Data for the time intervals between these

points will be available for a later report, but will not be a,.ilable.in time for the 1974:Multiplant -An,._l (prg, i-75

The initial 1974.entrainment impact analysis will be refined

when the complete set of 1974 data is available and will be

included in later reports.

c. The mark-recapture data for making a spring estimate of the

fall 1973 population are currently being analyzed for standing

crop estimates. Impingement data for Bowline, Lovett, Roseton,

and Danskammer through January 1974 have been reviewed. The

impingement data for the plants infrequently sampled will be

interpolated over time (between sample days) to estimate total

impingement on-the basis of pumping rates.

Ill. STOCK ASSESSMENT

A. Historical Data Base Analysis

Year-to-year variations in species composition, and year

class strength and abundance of striped bass, white perch, and Atlantic

tonco.d i-n the Hudson River in relation to selected env.i.ronmentaF parameters

are being analyzed to identify trends which may be attributed to an increase

in power plant-operations on the estuary.

STATUS

a. An examination, description, compilation of the Hudson River historical data base has been complied. Those suhsets which can

be compared are on file and being analyzed. Cursory analyses are

being conducted on catch data from:

1) Greeley, J.R., H.W. Curran, D.T. Ries, et al. 1937. A

Biological Survey of the Lower Hudson Watershed, (NYSDEC).

2) Rathjen, W.F. and L.C. Miller, 1957. Aspects of the early

life history of the striped bass (Roccus saxatilis) in the

Hudson River. New York Fish nd Game Journal 4 (1):43-60.

3) New.York University, 1973. Hudson River Ecosystem Studies.

Effects of Entrainment by the Indian Point Power Plant on Biota

in the Hudson River Estuary. Progress Report for 1971 and 1972.

For Consolidated Edison Company of New York, Inc.

szrvlces groupIII-1

4) New York University,.1974. Hudson River Ecosystem Studies.

Effects of Entrainment by the Indian Point Power Plant on

Biota in the Hudson River Estuary. Progress Report for 1973.

For Consolidated Edison Company of New York, Inc.

5) Quirk, Lawler & Matusky Engineers, 1973. Roseton/Danskammer

Point Generating Station Aquatic Ecology Study 1971-1972. For

Central HudsonGas & Electric Corporation, Consolidated Edison

Company of New York, Inc., and Niagara Mohawk Power Corporation.

October 1973.

6) Quirk, Lawler & Matusky Engineers, 1973. Roseton/Danskammer

Point Generating Station Aquatic Ecology Studies. 1971-1972.

Annndicies Olctober 1973. For Central Hudson Gas & Electric

Corporation and Niagara Mohawk Power Corporation.

7) Central Hudson, 1973. Central Hudson. 1973 Data. Data Courtesy

of Central .Hudson Gas & Electric Corporation.

8) Quirk, Lawler & Matusky Engineers, 1974.. Pre-operational Report

on Ecological Studies Conducted 'in .,the Area of-"Haverstraw Bay

during 1971-1972. Preparedfor Orange & Rockland Utilities, Inc.

9) Lawler, Matusky & Skelly Engineers, 1974. Hudson River Aquatic

Ecology Studies 1973. Bowline Point and Love-tt Generating.

Stations. For Orange & Rockland Utilities, Inc.

111-2 ser'Ace. .Jroup

More extensive analyses are being conducted on data from:

10) Hudson River Fisheries Investigations, 1965-68 (HRFI),

11) New York University Beach Seine Data, 1965-69 (NYU),

12) Indian Point. Ecological Survey Conducted by Raytheon. Company,

1969-70 (Raytheon),

13) Hudson River Ecological Study Conducted by Texas Instruments

Incorporated, 1972-74 (TI).

b. Past and present plant operational records from Bowline, Lovett,

Indian Point. fanskmmer, and Roseton are beiig analyzed to provide a historical backdrop of power plant operations which may be

impacting the Hudson River estuary.

c. A summary matrix of the prevailing environmental conditions i~n

the Hudson River since 1965 is being assembled. Year class strengths of striped bass, white perch and Atlantic tomcod are

being calculated for 1965-70 and 1972-74. The environmental

factors influencing yearly variations in year class size will

be assessed.

d. Catch-per-unit-effort figures for striped bass, white perch and

Atlantic tomcod, not separated by age, are being compared to describe pre- and post-plant operational changes in abundance

and distribution.

111-3 services group

lo

e. Ichthyoplankton gear comparability test results are being

evaluated, and if applicable, will be used-to study comparability

of the ichthyoplankton historical data base. A discussion of

ichthyoplankton abundance and distribution data base along with

gear selectivity and comparability studies will be forthcoming

in a later report.

f. Commercial fishery records from the Hudson River between Weehauken,

New Jersey and Hudson, New York (1913-72) have been assembled

and are being compared with gear and fishing intensity statistics

to generate catch/effort values and describe trends in striped

bass commerical landi ngs.

B. Vulnerability Matrix

A descriptive vulnerability matrix for striped bass, white

perch, and Atlantic tomcod in the Hudson River is being developed based on

the literature and field and laboratory studies by TI and others, on.life

history., behavior, and spatio-temporal distribution and abundance. This

matrfx:,will be used to assess thes.usceptibilfty thro h timeofalol ava.l

able. life stages of the key.,species to plant-induced mortalities at Bowline,

Lovett, Indian Point, Roseton and Danskammer..

STATUS

a. An extensive literature review of the life history, behavior and

physiology of striped bass, white perch and Atlantic tomcod is

I1I-4 services

continuing.

b. Data from the ichthyoplankton and fisheries field sampling

operations, collected during 1973, are being further analyzed

to describe the spatio-temporal abundance, distribution, and

movement, patterns of eggs, larvae, juveniles, yearlings,.andadults (where available) of key species .from river miles

(RM) 12 through 152-as well as in a 13 mile region around each

plant site. The 13 mile region approximately 6.5 miles above

and 6.5 miles below each plant is based on an estimated maximum

tidal excursion..

c., Near-field transect data collected by NYU and LMS durinq 1973

will be analyzed in conjunction with impingement and entrainment

monitoring data collected at each plant to assess the near-field

distribution and abundance patterns versus susceptibility to plant

impact.

d. Ichthyoplankton and fisheries operations for 1974 are on schedule

and data are being compiled for analysis and inclusion in the

Multiplant Annual Report. Movements of fish marked through

August in conjunction with the 1974 mark-recapture program will

also be analyzed and discussed. Data from the remainder of 1974

will be included in a later report.

e. Abundance and distribution data from 1974 as well as general life

111-5 services group

111-5 .services qroup

history-behavior information for each key species is being

analyzed in relation to important physical/chemical variables.

A Summary of the 1974 ichthyoplankton and fisheries field

sampling programs follows.

I. Ichthyoilankton Operations

The objective of the ichthyoplankton operations is to

determine the longitudinal and vertical distribution of fish eggs, larvae,

and early juveniles, particularly striped bass, in the Hudson River estuary.

a. Field

A description and status of the 1974 ichthyoplankton.

operations field program are summarized in Table 2.

1). Ichthyoplankton River Survey and Shoals River Survey kc ay and Late)

From mid-April until mid-August, the Hudson.River estuary

.was continuously sampled from river mile (RM) 14 to 140. A stratified

random sampling scheme was employed. Sample locations-and sites within.

strata (twelve river regions) were selected from a random number table.

River volume was .calculated for each region. Those regions with greater

volumes in channel and shoal areas were sampled proportionately more

intensively.

Only one tow was made at each site during a sampling period.

111f-6

* I~r~___ j

Table 2. Description and Status of 1974 Ichthyoplankton Operations Field Programs.

STUDY AREA SAMPLING- SCHEDU .E

PROGRAM, DESCRIPTION 1) Geographic region 1) Frequency 2) River mile 2) Sampling period 3) No. of samples PROGRAM STATUS

Ichthyop-ankton Early River -Survey 1) Yonkers to Albany 1) Weekly

2) 14-140 2) 4/16/74. to 5/12/74

Compl ete

Ichthyoplankton Late River Survey 1) Yonkers to Albany 1) Weekly

2) 14-140 2) 6/17/74 to 8/15/74

Compl ete

Shoals Early River Survey 1) Yonkers to Pough- 1) Weekly

keepsie 2) 4/16/74 to 9 1. _L77

3) 25 Complete

ShoalsLate River Survey 1) Yonkers to Pough- 1) Weekly

keepsie 2) 6/17/74 to 2) 14-77 8/1 5/74 3) 80 Complete

Egg Deposition Ichthyoplankton 1) Yonkers to Albany 1) Every four

2) 14-140 six days 3) 74 2) 5/13/74 to

6/16/74 Complete

Egg Deposition 1) Yonkers to Pough- 1) Every fourShoals keepsie six days

2) 14-77 2) 5/13/74 to 3) 25 6/16/74

Complete

Shoals Fall 1). Yonkers to Pough- 1) Weekly River Survey keepsie 2) 8/16/74 to

2) 14-77 12/31/74 3) 100 On-going

111-7 services group

II11-7 services grou~p

Gear type used (either a 1-meter Tucker traw.l or a 1-meter epibenthic sled)

was dependent upon site location. All colllections during the early river

surveys. (mid-April to mid-May) and late river surveys (mid-June to mid-August)

used gear with 500u mesh nets.

Sample site selection during the early river surveys had 3/4

emphasis in channel areas and 1/4 emphasis in shoal areas. Sample site

selection during the late river surveys had 1/2 emphasis in channel areas

and 1/2 emphasis in shoal areas.

2). Ichthyoplankton Egg Deposition and Shoals Egg Deposition Collections

From m id-May until mid-June, the HudsonRiver estuary was

continuously sampled for eggs from RM-14 to 140 once every four to six days.

Sample locations and sites within strata were selected from a random number

table in the same manner as for the ichthyoplankton river and shoals river

surveys. One tow was made at each site during a sampling period with

either a Tucker trawl or an epibenthic sled equipped with 500u mesh nets.

Sa'mple site selection during the time of egg deposition collections had 3/4

emphasis in channel areas and 1/4 emphasis in shoal-areas:.

3). Shoals Fall River Survey

From mid-August until the present, shoal areas ( 20 ft depth)

of the Hudson River estuary have been sampled with ichthyoplankton gear from

RM 14 through 76. Sampling will continue until December 31, 1974 or until

river ice makes sampling impossible. Sample sites within strata .are

III-8 s~er~t~ces 'o~spsprvzces groupIII--8

_.

selected from a random number table. One tow is made at each site during a sampling period with an epibenthic sled employing a 3000u mesh net equipped with a modified fyke cod-end. This study is also augmenting the mark

recapture program by providing striped bass and white perch recaptures and

marking adult white perch with Dennison tags. As of September 13, 101 adult

white perch have been marked. Sample site selection during,.the .shoai,,s fall river survey has 1/4 emphasis in areas with greater than 20 ft depths

and 3/4 emphasis in shoal areas with less than 20 ft depths.

b. Laboratory.

Laboratory operations are similar. to those procedures used auring 19/3 (Texas Instruments, 1974b). Description and status of the

laboratory effort are summarized in Table 3.

1). Laboratory Effort Overview

The ichthyoplankton and shoals field effort for the time of the early and late river surveys and during the time of egg disposition

collected 2,629 samples. As of September 13, 1,725 of these samples were

picked, and 1431 identified. The laboratory reduction is complete for the early river survey and the egg deposition period, and is continuing on

schedule for late river survey collections.

The shoals fall survey effort has produced 796 samples as of September 13, and 473 of these samples were reduced. This effort is also on

schedule.

III-9 services group

TABLE 3. Description and Status of 1974 Ichthyoplankton'Operations Laboratory Programs.

PROGRAM DESCRIPTION SAMPLES COLLECTED SAMPLES REDUCED PROGRAM TO DATE TO DATE STATUS (9/13/74) (9/13/74)

Combined Early Ichthyoplankton and Shoals River Surveys (4/16/74 to 5/12/74)

Combined Ichthyoplankton. and Shoals Egg Deposition Sampl i ng 5/13/74 to 6/16/74)

ornbined. Late".Ichthyo

p1lankton an d S na1 s River Surveys (6/17/74 to 8/15/74)

Shoals Fall River Survey (8/16/74 to Present)

282

774

1571

796

282 (picked and identified)

774 (picked and identified)

667 In i r 1z r!

443 (identified)

473 (Processed)

IIl-10

Complete

Complete

On-Going

On-Going

9 P

2. Fisheries Operations

a. Beach Seine Survey Frogra.ins

The purpose of the beach seine survey is to provide information

on the relative abundance, distribution and movements of juvenile and. adult

fishes, particularly str-iped bass and white"perch, - in' the shore zone .between

the George Washington Bridge (RM 12)-and the Troy Lock (RM 153).

River-length sampling was initiated on 10 April and will

continue during daylight periods until 'weather conditions no longer permit.

Specimens are collected by 100-ft beach seine (1/4-in mesh bays, 3/8-in mesh

wings) set perpendicular to the shoreline and towed i.n a semi-circle to the

beaMch. The smiple sites for a given week are selected from a total of 241

beaches located between RM 12 and 153 according to a stratified random

sampling design. Young-of-the-year collected through mid-August have -been

identified and enumerated, white perch yearling and older individuals

collected through mid-September have been identified and enumerated.

Night beach seine sampling began on 4 August and will

continue .through November. Approximately 14 samples are being collected in

the Indian Point and Cornwall Regions each week. All specimens collected

through mid-September have been identified.

Field and laboratory beach seine survey efforts are

summarized in Table 4.

HI-il r~e group

Table 4. Description and Status of 1974 Laboratory Programs.

Fisheries Operations Field and

PKU A IM DESCRIPTION

STUDY AREA 1. Geographic Region 2. River Mile (Inclu

sive) 3. No. of Sites

SAMPLING SCHEDULE PROGRAM I. Frequency 2. Sampling Period

Beach Seine 1. Yonkers-Albany 1. Weekly On-Going Survey Field 2. 12-152 2. 4/10/74 to (Day) 3. 241--stratified 12/31/74

random sample

Beach'Seine I. Yonkers-Albany 1. Weekly On-Going Suvey Labora- 2. 12-152 2. 6/1/74 to (young-of-year tory (Day) 3. 241-stratified identified

random sample through 8/15/74)

Beach Seine I. Indian Point, Corn- 1. Weekly On-Going Survey Field wall 2. 8/4/74 to (Night) 2. 39-46, 56-61 11/30/74

3. 31-stratified random. sample

Beach Seine 1. Indian Point, Corn- I Weekly On-Going Survey Labora- wall 2. 8/4/74:to (you'ng-of-year tory (Night) 2. 39-46, 56-61 11/30/74 identified

3. 31-stratified through 9/15/75) random sample

Mark-Recapture 1. Yonkers-Albany- 1. Daily Marking: (winter-spring) 2. 12-152 2. 1/1/74 to Complete

3. All Sites 6/10/74 Recapture: On-Going

-Mark-Recapture 1. Yonkers-Albany 1. Daily Marking: (Fall) 2. 12-152 2. 9/l/74*to Complete

3. All Sites 12/31/74 Recapture: On-Going

Axiam Bottom 1. Yonkers-Cornwall 1. Bi -Wekly On-Going Trawl Survey 2. 12-61 2. 4/4/74 (Day Only) 3. 42 12/31/74

111-12 services group

111-12 F ervicces group

b. Axial Bottom Trawl Sue\vyPro qram

The axial bottom trawl survey is designed to collect inform

tion on the species composition, abundance, distribution, and movements of

juvenile and adult fish, particularly striped bass, white perch, and Atlantic

tomcod, in shoal and channelareas of the Hudson River. This survey also

supplies additional .effort to.thewhite perch and striped bassmark-recaptue,.e

program through the recapture of marked specimens.

Sampling at 42 regular bottom trawl stations located in shoal

and channel areas between the rGeorge Washington Bridge (RM 12) and the

Newburgh-Beacon Bridge (RM 61) began on 4 April. Sampling will continue

during- d -ylight4 periods at bi -- in '' i y4nte ri I c as I ong as wenather cndritions

permit. One survey inMay an.d one survey in July were not completed due to

mechanical problems.

The otter-type bottom trawl measures 45-ft (13.5m) in total

length with head and foot ropes of 25-ft (7.8m) and 30-ft (9.3m), respectively.

The trawl bag consists of 1 1/2-in (3.8cm) stretch mesh knotless nylon net

with 1 1/4-in (3.2cm) stretch mesh cod-end and an outer bag of 1 1/2-in

(0.8cm) mesh knotless nylon net. The trawl is equipped with two -.2 1/2 x

4-ft (0.8 x 1.2m) doors and is towed against the current at a speed of 1.3

m/sec for 5 minutes. A minimum cable length-to-depth ratio of 3:1 is

maintained while towing.

111-13 s~r~~~ces groupserVECS's groupI i I - 3

Field axial trawl survey efforts are summarized in Table 3.

c. Mark-Recaptre Program

The purpose of the mark-recapture study is to determine the

population size and movements of white perch, striped bass and Atlantic

tomcod. Gears used to collect/specimens, in this program include beach

seines, box traps, gill nets, epibenthic sled and bottom trawl.

The numbers of striped bass, white perch, and Atlantic tomcod

marked and recaptured from January through August 1974, are presented in

Table 5. Yearling and older striped bass and white perch were fin clipped

or tagged (depending on size) from 1 April through 10 June during 1974.

Marking operations:were susoended durina the remainder of June and July

due to very high mortalities resulting-from high summer water temperature

700 F). Tagging operations were resumed during late August when survival

tests indicated reduced mortalities. and will continue until weather

conditions no longer permit. Atlantic tomcod.were marked from January

through March; recovery effort continued through August.

d. Lower Estuary SurveN Program

A preliminary fisheries survey of the lower Hudson River

estuary began in July 1974 and is designed, primarily, to supplement the

mark-recapture program through recovery effort for striped bass, white perch,

and Atlantic tomcod marked and released in the main river (RM 12 - 153).

•The survey also provides spatio-temporal distribution information on young

.IIl-14 servlce -'3 S-roup

TABLE 5. Number of white perch, striped bass and Atlantic tomcod marked and recaptured from Janaury through August, 1974.

WHITE PERCH STRIPED BASS ATLANTIC TOMCOD

No. Fin Clipped

No. Floy Tagged

No. Dennison Tagged

No. Carlin Tagged

No. Fin Clip Returns

No. Floy Returns

No. Dennison Returns

No. Carlin Returns

2,3125.,360

1 ,979

7,956

325a

6 6 7 b

a - Includes 284 hatchery fish released from physiology experiments, which are not used in population estimates

b - From 1973 and 1974 marking periods c - From 1974 marking period

111-15 services ~rou~

DATA

III-15 services group

striped bass in the lower estuary and life history data on other anadromous

fish species which occur. in the Hudson River. Areas being sampled .include

the western .portions of the north and south shores of Long Island, the

eastern shore of Staten Island, and Lower New York Bay. Sampling sites are

being surveyed with 200-foot beach seine, bottom trawl, Im2 epibenthic sled,

gill net.and box trap (for gear description, and dimensions, see Texas

Instruments 1974b) at approximately bi-weekly intervals.

STATUS

1). A beach seine survey was inititated on 8 July along the north

shore of Long Island and on 15 July in Jamaica Bay along the

south shore. Beach seine sampling on the east shore of Staten

is_ aid was begun on 2 July. S&ip8ing wIll continue ......

November in each of these areas. Through October, a total of

290 samples have been taken (Table 6).

2). Beach seining has yielded fin clipped yearling striped bass.

Since September, striped bass and white perch have also been

fin clipped or tagged and released.

3). Sampling with bottom trawl and lm2 epibenthic sled on 9 Sep-,,

tember off Staten Island and on 16 September along the-north

shore of Long Island. Through October, 132 bottom trawl

samples and 33 epibenthic sled samples were taken (Table 6).

Suitable regular sampling sites are being selected.

111-16

Table 6. Description and Status August - October 1974.

of 1974 Lower Estuary Survey,

NUMBER OF -TOTAL NUMBER OF STUDY AREA GEAR SAMPLING SAMPLES THROUGH

SITES 1 OCTOBER

Manhasset Bay Seine 14 77 Trawl 13 31 Sled 9 9

Little Neck Bay Seine 12. 48 Trawl 11 24 Sled- 9 9

Hempstead Harbor Seine 12 34 Trawl 15 35 Sled 15 15

Jamaica Bay Seine 26 75

Staten Island Seine 12 54 Trawl 12 42

Eastchester Bay Seine 1

East River Seine.

Bottom trawl and epibenthic sled samples are taken at the same sites.

III~l7 serv~ces ~1!-17 services g r L. v

4). Fixed gear (gill net and box trap) sampling began on 30

September along the north shore of Long Island and on 23

September in Jamaica Bay and Staten Island's Great Kill

Harbor. The selection of suitable box' traps and gill net

sampling sites is being explored. Trawling will continue

through the winter months if weather permits.

e. Water Chemistry Program

The water 'chemistry program is directed toward measuring and

defining the fluctuations of chemical and physical parameters in the Hudson

River estuary. These data provide support for the ichthyoplankton and

fisheries programs. Water temperature, conductivity/salinity, turbidity,

dissolved oxygen, and pH are measured concurrently with the sampling efforts.

In addition, records of freshwater runoff are obtained from the USGS gaging

station at Green Island, New York for reference. Details of the water

chemistry sampling gear and procedures are presented in Texas Instruments,

1974 a & b.

C. Compensation

An empirically based rationale for interpreting the longterm

impact of power plants on key Hudson River fish stocks is being developed

by examining the extent to which compensatory mechanisms are operating

in the fish populations. Compensation refers to the process whereby fish

populations are regulated in a density dependent fashion, i.e., the effect

ses Aces

on the population varies with the density. Compensatory mechanisms can act

like governors on an engine and protect fish populations from catastrophic

overexpansion and, within limits, also buffer the effects ofincreased

mortality. Emphasis is being placed on the relationships among vital

statistics such as density, growth, and mortality in striped bass and

white-perch populations. If compensatory mechanisms are operating, the

long term impact of power plants may prove to be less than the short term

direct impact.

STATUS

. An extensive literature review of studies which have documented

the function of compensatory e in anima p .op.ulatin

is on-going.

2. Examination of several mechanisms by which striped bass and

white perch populations potentially compensate for plant-in

duced mortality is on-going.

3. Compensation by increased growth rates of young-of-the-year

fish is being evaluated by comparing growth rates with catch

per unit effort indices of abundance in several years. Data

collected during 1972 - 1974 by Texas Instruments Incorporated

and data obtained from Raytheon for 1969 - 1970 is being com

bined for analysis. If increased growth occurs during years

of low population density, the presence of compensation will

111-19 serv~ces grour~

11I- 19 services group

be indicated. All relevant historical data have been merged

into a single file'Which is being used for the anlaysis.

4. Commercial Hudson River fisheries catch data is being examined for

density dependent population changes in adult striped bass (1965

present) and white perch (1955-1963). Commercial catch data

are being transformed into density indices.

5. Since many years of data are required for definitive studies

of density dependent population phenomena, statements concerning

possible compensatory mechanisms of types other than those

considered in 3 and 4 above will be highly tentative in the 1974

Multiplant Annual Report. Estimates of ichthyoplankton density

anid survival rates and mark-recapture estimates of population

densities will be available for only 1973 and 1974. If the

relationships of. these variables observed between years indicate

that compensation may have occurred, qualitative statements

will be made to that effect.

I 11-20

IV. LITERATURE CITED

Texas Instruments Incorporated, 1974a. Hudson River Ecological Study in the

in the Area of Indian Point3 1973 Annual Report for Consoli

dated Edison Company of New York, Inc., July 1974.

Texas Instruments Incorporated, 1974b. Fisheries Survey of the Hudson River,

March-December, 1973, Vol. IV. Draft copy of Report.for

Consolidated Edison Company of New York, Inc., September 1974.

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