ML073340943

2005 Year Class Report for the Hudson River Estuary Monitoring Program - Appendix G, Summary of Atlantic Tomcod Food Habits Study

ML073340943
Person / Time
Site:	Indian Point
Issue date:	01/31/2007
From:	ASA Analysis & Communication
To:	Dynegy Roseton, Entergy Nuclear Indian Point 2, Entergy Nuclear Indian Point 3, Mirant Bowline, Office of Nuclear Reactor Regulation
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Download: ML073340943 (12)

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Appendix G Summary of Atlantic Tomcod Food Habits Study

APPENDIX G CONTENTS G.1 STUDY OBJECTIVE G.2 METHODS G.3 RESULTS LIST OF FIGURES Number Title G-1 Monthly and regional percent composition (by weight) of major food items from Atlantic tomcod food habit study, 2005.

G-2 Percent composition (by weight) of major food items by length category of Atlantic tomcod from food habit study, 2005.

G-3 Percent composition (by weight) of major food items by length category and region from Atlantic tomcod food habit study, 2005.

LIST OF TABLES Number Title G-1 Number of stomachs analyzed for Atlantic tomcod food habit study, 2005.

G-2 Length frequency distribution of Atlantic tomcod analyzed for food habit study, 2005.

G-3 Total weight, count, and percent composition of food items from Atlantic tomcod food habit study, 2005.

G-4 Summary of food items from Atlantic tomcod food habit study by month and region, 2005.

2005 Year Class Report

G.1 STUDY OBJECTIVE The objective of the Atlantic tomcod food habits study was to examine the stomach contents of juvenile and adult Atlantic tomcod in order to detect differences in food habits throughout the Hudson River estuary and the possibility of cannibalism among Atlantic tomcod.

G.2 METHODS A maximum of 100 juvenile and 25 adult Atlantic tomcod per river run were collected during the Fall Juvenile Survey. Up to 20 juvenile and 5 adult fish per river region (as defined below for the Atlantic tomcod food habits study) were preserved in 10 percent formalin and returned to the laboratory for analysis.

Atlantic Tomcod Food Habits River Regions FJS Region Region River Miles Designations 21 0-23 BT, YK 22 24-38 TZ, CH 23 39-46 IP 24 47-76 WP, CW, PK 25 77-152 HP, KG, SG, CS, AL In the laboratory, the entire stomach was removed from the fish and the contents carefully placed into a dissecting pan or petri dish. The contents were identified to family level for fish and to order for invertebrates, except for gammarid amphipods which were identified to family if possible. For each type of food item, a count and weight to the nearest hundredth gram were recorded on the laboratory data sheet. Other recorded information included sample number, region, and river run as well as fish length and life stage. Age, sex, and sexual condition were determined on Atlantic tomcod from river runs 9 through 11 only.

G.3 RESULTS A total of 235 Atlantic tomcod stomachs, 227 juvenile fish and 8 adult fish, were analyzed in 2005 (Table G-1). Fish were captured from 11 of the 13 designated regions of the Hudson River estuary from July through November 2005, with 98 percent of the fish caught during the summer. Juvenile fish were collected mostly from the lower and middle estuary regions between Battery and Hyde Park whereas adult fish were mainly collected in the lower estuary regions. Of the Atlantic tomcod analyzed, 86 percent measured 90 mm or less and most of these were found in the lower and middle estuary (Table G-2). Fish larger than 90 mm were found mainly in the lower estuary.

The most abundant food item by weight found in juvenile Atlantic tomcod was sand shrimp (Crangon), comprising 44 percent of the total weight of all food items found in this age group (Table G-3). The other food items that made up 95 percent of the juvenile Atlantic tomcod diet were gammarid amphipods (Gammarus), mysids (Neomysis), and non-gammarid amphipods (Amphipoda). For adult Atlantic tomcod, Crangon was also the most abundant food item by weight, comprising 95 percent of the diet. The other food items that made up the adult Atlantic tomcod diet were Neomysis and unidentified invertebrate remains. No fish taxa were found in the stomachs of the analyzed Atlantic tomcod. A complete listing of all food items by month and region is presented in Table G-4.

2005 Year Class Report

Consumption of the major food items were compared by month (Figure G-1, top graph), by region (Figure G-1, bottom graph), and by length (Figure G-2). Crangon was the major food item in August and October, whereas Gammerus was consumed mainly in July and November.

Crangon and Neomysis were the dominant food items in the lower estuary regions, but Gammarus dominated in regions from Indian Point to the north. The smallest Atlantic tomcod consumed more Gammarus than other food items, but as fish grew, Crangon became the dominant food item.

To ascertain whether fish size or location was more important in determining patterns in diet, a comparison of food items from the eight lower regions of the estuary investigated changes with region and length (Figure G-3). In the lower estuary (Battery and Yonkers regions), all sizes of fish consumed mainly Crangon and Neomysis. In the middle estuary (Indian Point and above),

location may also determine food choice as evidenced by the consumption of mainly Gammarus and Amphipoda by all sizes of fish.

2005 Year Class Report

Percent Composition of Food Items by Month 100 80 Percent Composition (by weight) 60 40 20 0

July August September October November December Percent Composition of Food Items by Region 100 80 Percent Composition (by weight) 60 40 20 0

BT YK TZ CH IP WP CW PK HP KG SG CS AL Region Legend:

Crangon Gammarus Neomysis Amphipoda All Others Figure G-1. Monthly and regional percent composition (by weight) of major food items from Atlantic tomcod food habit study, 2005.

Percent Composition of Food Items by Fish Length Category 100%

80%

Percent Composition (by weight) 60%

40%

20%

0%

<=70 71-80 81-90 91-100 101-110 111-120 121-130 131-140 141-150 >150 Length (mm)

Legend:

Crangon Gammarus Neomysis Amphipoda All Others Figure G-2. Percent composition (by weight) of major food items by length category of Atlantic tomcod from food habit study, 2005.

Battery Yonkers 100 100 80 80 60 60 40 40 20 20 0 0

<=90 91-120 121-150 >150 <=90 91-120 121-150 >150 Tappan Zee Croton-Haverstraw 100 100 80 80 60 60 40 40 Percent Composition (by weight 20 20 0 0

<=90 91-120 121-150 >150 <=90 91-120 121-150 >150 Indian Point West Point 100 100 80 80 60 60 40 40 20 20 0 0

<=90 91-120 121-150 >150 <=90 91-120 121-150 >150 Cornwall Poughkeepsie 100 100 80 80 60 60 40 40 20 20 0 0

<=90 91-120 121-150 >150 <=90 91-120 121-150 >150 Length Category (mm)

Legend: Crangon Gammarus Neomysis Amphipoda All Others Figure G-3. Percent composition (by weight) of major food items by length category and region from Atlantic tomcod food habit study, 2005.

Table G-1 Number of Stomachs Analyzed for Atlantic Tomcod Food Habit Study, 2005 July August September October November December Total Juvenile Battery 30 22 -- 2 -- -- 54 Yonkers 10 13 1 -- -- -- 24 Tappan Zee 22 -- -- -- -- -- 22 Croton-Haverstraw 6 -- -- -- -- -- 6 Indian Point 40 -- -- -- -- -- 40 West Point 10 -- -- -- -- -- 10 Cornwall 5 -- -- -- -- -- 5 Poughkeepsie 25 -- -- -- -- -- 25 Hyde Park 37 -- -- -- 1 -- 38 Kingston 1 -- -- -- -- -- 1 Saugerties 2 -- -- -- -- -- 2 Catskill -- -- -- -- -- -- 0 Albany -- -- -- -- -- -- 0 Total 188 35 1 2 1 0 227 Adult Battery -- 6 -- -- -- -- 6 Yonkers -- 2 -- -- -- -- 2 Tappan Zee -- -- -- -- -- -- 0 Croton-Haverstraw -- -- -- -- -- -- 0 Indian Point -- -- -- -- -- -- 0 West Point -- -- -- -- -- -- 0 Cornwall -- -- -- -- -- -- 0 Poughkeepsie -- -- -- -- -- -- 0 Hyde Park -- -- -- -- -- -- 0 Kingston -- -- -- -- -- -- 0 Saugerties -- -- -- -- -- -- 0 Catskill -- -- -- -- -- -- 0 Albany -- -- -- -- -- -- 0 Total 0 8 0 0 0 0 8 Total 188 43 1 2 1 0 235

-- = None collected.

2005 Year Class Report

Table G-2 Length Frequency Distribution of Atlantic Tomcod Analyzed for Food Habit Study, 2005 Length Category (mm)

<=70 71-80 81-90 91-100 101-110 111-120 121-130 131-140 141-150 >150 Battery 17 8 12 12 5 -- -- -- -- 6 Yonkers 7 4 9 3 1 -- -- -- -- 2 Tappan Zee 11 9 2 -- -- -- -- -- -- --

Croton-Haverstraw 4 1 1 -- -- -- -- -- -- --

Indian Point 25 10 2 3 -- -- -- -- -- --

West Point 7 2 1 -- -- -- -- -- -- --

Cornwall 2 2 1 -- -- -- -- -- -- --

Poughkeepsie 21 4 -- -- -- -- -- -- -- --

Hyde Park 26 8 3 -- -- -- 1 -- -- --

Kingston -- -- 1 -- -- -- -- -- -- --

Saugerties 2 -- -- -- -- -- -- -- -- --

Catskill -- -- -- -- -- -- -- -- -- --

Albany -- -- -- -- -- -- -- -- -- --

Total 122 48 32 18 6 0 1 0 0 8

-- = None collected.

2005 Year Class Report

Table G-3 Total Weight, Count, and Percent Composition of Food Items from Atlantic Tomcod Food Habit Study, 2005 Percent of Percent of Weight Total Total Class Order Genus or Family Species (g)a Weight Count Count Juvenile Malacostraca Decapoda Crangon 3.81 44.15 89 5.20 Malacostraca Amphipoda Gammarus 2.07 23.99 567 33.14 Malacostraca Mysida Neomysis 1.84 21.32 481 28.11 Malacostraca Amphipoda 0.48 5.56 362 21.16 Invert remains 0.11 1.27 29 1.69 Malacostraca Decapoda 0.10 1.16 13 0.76 Malacostraca Cumacea 0.08 0.93 90 5.26 Plant remains 0.06 0.70 15 0.88 Insecta Diptera (Pupae) 0.02 0.23 3 0.18 Polychaeta 0.02 0.23 2 0.12 Inorganic mat. 0.02 0.23 3 0.18 Insecta Odonata (Juvenile) 0.01 0.12 1 0.06 Detritus 0.01 0.12 3 0.18 Empty stomach < min. 0 5 0.29 Fish eggs < min. 0 2 0.12 Pelecypoda < min. 0 5 0.29 Gastropoda < min. 0 1 0.06 Insecta Diptera Chironomidae (Larvae) < min. 0 13 0.76 Insecta Trichoptera < min. 0 1 0.06 Malacostraca Isopoda Chirodotea < min. 0 1 0.06 Malacostraca Isopoda Edotea < min. 0 1 0.06 Malacostraca Isopoda Cyathura < min. 0 1 0.06 Malacostraca Isopoda < min. 0 4 0.23 Maxillipoda Copepoda < min. 0 14 0.82 Ostracoda < min. 0 1 0.06 Branchiopoda Diplostraca Cladocera < min. 0 3 0.18 Oligochaeta < min. 0 1 0.06 Total 8.63 100 1711 100 Adult Malacostraca Decapoda Crangon 1.57 94.58 20 57.14 Malacostraca Mysida Neomysis 0.07 4.22 14 40.00 Invert remains 0.02 1.20 1 2.86 Total 1.66 100 35 100 a

For some food items, weights were less than the minimum weight measurable by instrumentation and are represented here as < min.

Table G-4 Summary of Food Items from Atlantic Tomcod Food Habit Study by Month and Region, 2005 Croton Battery Yonkers Tappan Zee Indian Point West Point Cornwall Poughkeepsie Hyde Park Kingston Saugerties Catskill Albany Haverstraw Ct. Wt. Ct. Wt. Ct. Wt. Ct. Wt. Ct. Wt. Ct. Wt. Ct. Wt. Ct. Wt. Ct. Wt. Ct. Wt. Ct. Wt. Ct. Wt. Ct. Wt.

July Empty stomach - - - - 1 < min. 2 < min. - - - - - - - - 1 < min. - - - - - - - -

Fish eggs - - - - - - - - - - - - - - - - 2 < min. - - - - - - - -

Pelecypoda 1 < min. - - - - - - - - - - 1 < min. - - 3 < min. - - - - - - - -

Gastropoda - - - - - - - - 1 < min. - - - - - - - - - - - - - - - -

Chironomidae (Larvae) - - - - 1 < min. - - 1 < min. 1 < min. 4 < min. 1 < min. 5 < min. - - - - - - - -

Odonata (Juvenile) - - - - - - - - 1 0.01 - - - - - - - - - - - - - - - -

Trichoptera - - - - - - - - - - - - - - 1 < min. - - - - - - - - - -

Diptera (Pupae) - - - - - - - - 1 0.01 - - 1 0.01 1 < min. - - - - - - - - - -

Crangon 14 0.45 11 0.28 3 0.1 - - 1 < min. - - - - - - - - - - - - - - - -

Decapoda 5 0.01 - - 2 0.03 - - 1 0.04 - - - - - - - - - - - - - - - -

Gammarus - - - - 4 0.01 1 < min. 53 0.23 47 0.17 30 0.13 162 0.52 214 0.8 - - 16 0.04 - - - -

Chirodotea - - - - - - - - - - 1 < min. - - - - - - - - - - - - - -

Edotea 1 < min. - - - - - - - - - - - - - - - - - - - - - - - -

Cyathura - - - - - - - - - - - - - - 1 < min. - - - - - - - - - -

Cumacea 13 < min. - - 51 0.06 - - - - - - - - - - - - - - - - - - - -

Neomysis 268 1.01 34 0.12 58 0.3 - - 13 0.01 - - - - - - - - - - - - - - - -

Isopoda 1 < min. - - - - - - - - 1 < min. 1 < min. 1 < min. - - - - - - - - - -

Amphipoda 3 < min. 2 < min. 116 0.11 - - 168 0.3 28 < min. 8 < min. - - 14 0.03 6 0.02 - - - - - -

Copepoda 3 < min. 2 < min. - - - - - - 9 < min. - - - - - - - - - - - - - -

Ostracoda - - - - - - - - - - - - - - - - 1 < min. - - - - - - - -

Cladocera - - - - - - - - - - - - - - 3 < min. - - - - - - - - - -

Oligochaeta - - - - - - - - - - - - - - - - 1 < min. - - - - - - - -

Polychaeta - - - - 1 0.01 - - - - - - - - - - - - - - - - - - - -

Plant remains - - - - - - - - 2 < min. 1 0.01 1 < min. 5 0.01 5 0.01 - - - - - - - -

Detritus - - - - - - - - - - - - - - - - 3 0.01 - - - - - - - -

Invert remains - - 1 0.01 4 0.01 3 < min. 7 0.01 3 0.03 2 0.01 1 0.01 6 0.03 - - 1 < min. - - - -

Inorganic mat. - - - - - - - - - - - - - - 2 0.01 1 0.01 - - - - - - - -

August Empty stomach 1 < min. - - - - - - - - - - - - - - - - - - - - - - - -

Crangon 49 3.06 27 1.29 - - - - - - - - - - - - - - - - - - - - - -

Decapoda 2 0.01 3 0.01 - - - - - - - - - - - - - - - - - - - - - -

Cumacea 3 < min. 5 < min. - - - - - - - - - - - - - - - - - - - - - -

Neomysis 87 0.35 34 0.11 - - - - - - - - - - - - - - - - - - - - - -

Amphipoda 2 0.01 11 0.01 - - - - - - - - - - - - - - - - - - - - - -

Polychaeta - - 1 0.01 - - - - - - - - - - - - - - - - - - - - - -

Invert remains 1 0.02 - - - - - - - - - - - - - - - - - - - - - - - -

(Continued)

NOTE: All weights are in grams. For some food items, weights were less than the minimum weight measurable by instrumentation and are represented here as < min.

Table G-4 (Continued)

Croton Battery Yonkers Tappan Zee Indian Point West Point Cornwall Poughkeepsie Hyde Park Kingston Saugerties Catskill Albany Haverstraw Ct. Wt. Ct. Wt. Ct. Wt. Ct. Wt. Ct. Wt. Ct. Wt. Ct. Wt. Ct. Wt. Ct. Wt. Ct. Wt. Ct. Wt. Ct. Wt. Ct. Wt.

September Cumacea - - 18 0.02 - - - - - - - - - - - - - - - - - - - - - -

Amphipoda - - 1 < min. - - - - - - - - - - - - - - - - - - - - - -

October Crangon 4 0.2 - - - - - - - - - - - - - - - - - - - - - - - -

Neomysis 1 0.01 - - - - - - - - - - - - - - - - - - - - - - - -

Amphipoda 3 < min. - - - - - - - - - - - - - - - - - - - - - - - -

November Gammarus - - - - - - - - - - - - - - - - 40 0.17 - - - - - - - -

Plant remains - - - - - - - - - - - - - - - - 1 0.03 - - - - - - - -

Invert remains - - - - - - - - - - - - - - - - 1 < min. - - - - - - - -

NOTE: All weights are in grams. For some food items, weights were less than the minimum weight measurable by instrumentation and are represented here as < min.