bluefish, Pomatomus saltatrix, striped bass, Mo- 

 rone soxatilis, are probably the most important in 

 terms of biomass and commercial value. How- 

 ever, commercial fishing for the American eel and 

 striped bass has been banned in the Hudson since 

 1976 because both species are contaminated with 

 higher levels of toxic polychlorinated biphenyls 

 (PCB's) than most other Hudson River fish spe- 

 cies. 



To date, only one published paper has touched 

 upon the diet of prespawning Hudson River 

 striped bass larger than 400 mm TL (Gardinier 

 and Hoff 1982), and their results for fish of that 

 size are based on less than 10 samples for which 

 fish remains were identified to species or family 

 level. The present paper describes the findings of 

 stomach content analysis for 510 striped bass, 

 most of which were prespawning adults larger 

 than 400 mm TL (Fig. 1) collected during the 

 spring months of 1973-75 by commercial gill nets 

 in the Tappan Zee region of the Hudson River. 



Description of Sampling Area and Methods 



The Tappan Zee gill-net fishery is located ap- 

 proximately 90 m south of the Tappan Zee Bridge 

 at river km 43.5 (measured from the Manhattan 

 Battery) in a relatively shallow section that is 4.5 

 km wide, a location through which many of the 

 spawners move on the way to upstream spawning 

 grounds. The staked gill nets were set perpendic- 

 ularly to the north-south current in water depths 



of 2.4-9.8 m and spanned a distance of approxi- 

 mately 1.6 km out to the dredged channel on the 

 east side of the river. Stretched mesh sizes were 

 11.4, 11.8, 12.1, 12.7, 13.3, and 14.0 cm. Water 

 temperatures during the sampling period ranged 

 from approximately 6° to 19.5°C, and the salinity 

 was essentially that of freshwater, rarely rising 

 above 300 mg/liter. Sampling dates included the 

 following periods in each year: 28 March-9 May 

 1973, 8 April-20 May 1974, and 6 April-19 May 

 1975. Fish were collected from the nets at 8-12 h 

 intervals, placed on ice, and taken directly to a 

 laboratory for total length (TL) measurements 

 and stomach content analysis. Prey items were 

 identified with the aid of a binocular dissecting 

 scope and frequency of occurrence was noted. 



Results 



Stomach Content Analysis 



A summary table of stomach content data, 

 pooled for the three years of analysis (Table 1), 

 shows that adult, prespawning striped bass were 

 highly piscivorous and that 89% of the stomachs 

 containing identified food items contained fish 

 and 21% contained invertebrate remains, primar- 

 ily those ofCrangon species. Clupeid species were 

 the most prevalent fish, with blueback herring, 

 Alosa aestivalis, predominating. Most of the clu- 

 peids were adult, prespawning herring, approxi- 

 mately 200 mm TL. 



NUMBER OF FISH = 510 



140 



400 450 500 550 600 650 700 750 800 850 900 950 1000 1050 



TOTAL LENGTH (mm) 



Figure 1. — Length distribution of Hudson River striped bass examined for stomach con- 

 tents. 



398 



