FISHERY BULLETIN: VOL. 82, NO. 2 



This standard tow covered an area of about 418 m 2 . 

 The New Jersey coastline from Cape May to 

 Shark River Inlet was subdivided into 19 areas 

 (Table 1). Stations were located by 3-point sextant 

 fixes and/or loran C, and grouped in intervals of 

 0-1.8 km (0-1 nmi) (0-0.9 and 0.9-1.8 km north of 

 Beach Haven Inlet), 1.8-3.7 km (1-2 nmi) and 3.7- 

 5.5 km (2-3 nmi) based on distance from land. 

 Inlets were used as latitudinal break points (Fig. 

 1 1. Because of the reduced sampling effort from 1.8 

 km offshore, these areas were larger than areas 

 inshore of 1.8 km. 



For statistical analysis, all tows on the same day 

 in a given area were considered replicates. The 

 Analysis of Variance (ANOVA) for the number of 

 crabs per tow had three sources of variation: Area, 

 time nested within area, and replicate tow nested 

 within time within area. Because each year's de- 

 sign was unbalanced, a pseudo-F procedure ( Hicks 

 1973) tested the significance of the area effect. 

 Data were log-transformed to stabilize the var- 

 iances. When areas were sampled more than once 

 in a given year, we tested differences between 

 sample dates using a completely randomized 

 one-way classification ANOVA. If the F-test was 

 significant, a Student-Neumann-Keuls proce- 

 dure for unequal group sizes tested for differences 

 between the means for each sample date (Zar 

 1974). 



TABLE 1 . — Description of areas of the New Jersey coast surveyed 

 from 1976 to 1979. 



Distance 



offshore 



(km) 



Area Southern boundary 



Northern boundary 



0-1 8 



1.8-3.7 



3.7-5.5 



1 Cape May Inlet 



2 Hereford Inlet 



3 Stone Harbor 



4 Townsends Inlet 



5 Corson Inlet 



6 Great Egg Harbor Inlet 

 Absecon Inlet 



8 Beach Haven Inlet 1 



9 Beach Haven Inlet 2 



10 Barnegat Inlet 



1 1 Barnegat Inlet 2 



12 Cape May Inlet 



13 Townsends Inlet 



14 Absecon Inlet 



15 Beach Haven Inlet 



16 Cape May Inlet 



17 Townsends Inlet 



18 Absecon Inlet 



19 Beach Haven Inlet 



Hereford Inlet 

 Stone Harbor 

 Townsends Inlet 

 Corson Inlet 

 Great Egg Harbor Inlet 

 Absecon Inlet 

 Beach Haven Inlet 

 Barnegat Inlet 

 Barnegat Inlet 

 Shark River Inlet 

 Shark River Inlet 

 Townsends Inlet 

 Absecon Inlet 

 Beach Haven Inlet 

 Shark River Inlet 

 Townsends Inlet 

 Absecon Inlet 

 Beach Haven Inlet 

 Shark River Inlet 



'0-0.9 km 

 2 9-1 8 km. 



Stomach Contents 



Thirty-six adult L. polyphemus were collected 

 between 10 July and 25 August 1978 for analysis of 



stomach contents. The results are grouped for 

 three locations: Stone Harbor (1 station, 5 indi- 

 viduals), Atlantic City (12 stations, 24 individu- 

 als), and Point Pleasant (3 stations, 7 individuals) 

 (Fig. 1). 



Complete digestive tracts were removed from 

 crabs aboard ship or shortly after returning to the 

 laboratory, fixed in 10% Formalin 5 seawater, and 

 later transferred into 70% ethanol until examina- 

 tion. Food, much of which was entangled with 

 mucus, was sorted under a 10 x stereoscope. The 

 number of bivalves was determined by counting 

 the number of umbones and dividing by 2. Shells 

 were measured by ocular micrometer or vernier 

 caliper. 



RESULTS 



Population Surveys 



1976 Survey 



Sampling commenced in mid-July and was most 

 extensive in late August and early September; no 

 areas north of Beach Haven Inlet were sampled. 

 Horseshoe crabs were present in over 909c of all 

 hauls in the first 1.8 km between Hereford Inlet 

 and Townsends Inlet, and from 1.8 to 3.7 km be- 

 tween Cape May and Townsends Inlet (Table 2). 

 More than 10 animals/ST were dredged from 1.8 to 

 3.7 km offshore between Cape May and Absecon 



5 Reference to trade names does not imply endorsement by the 

 National Marine Fisheries Service, NOAA. 



TABLE 2. — 1976 Limulus polyphemus survey results. Area 

 means are expressed as the number of crabs per standard tow, 

 as defined in the text. CV = coefficient of variation. Data were 

 log transformed prior to Analysis of Variance. Area locations 

 are shown in Table 1. 



Distance 

 offshore 



Area 



N sta- 

 tions 



% with 

 crabs 



Mean 



CV 



Maximum 



0-1.8 km 1 27 85.2 7.7 



2 12 66.7 41 



3 21 905 60 



4 7 714 11.2 



5 9 88 9 4 8 



6 8 62.5 2.4 



7 10 70.0 7.2 

 1.8-3 7 km 12 31 90.3 14.6 



13 28 78.6 125 



14 10 800 3.0 

 3 7-5.5 km 16 18 83.3 6 6 



17 16 62.5 25.4 



18 7 42.9 11 



Analysis of Variance: 



Source df SS MS 



Total 202 25994 



Area 12 40.08 3.34 



Time (area) 38 80.77 2.13 



Station (time (area)) 152 139 09 92 



081 

 1 27 

 065 

 1 14 

 1 05 

 1 01 

 1 01 

 069 

 236 

 068 

 0.97 

 2.72 

 1.30 



1.12 

 2.32 



25.7 

 107 

 15 

 35.3 

 15.0 



5.4 



20.0 



47.1 



145.7 



6.0 



268 



2774 



3.2 



ns 

 005 



384 



