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By Dave Grant  The Ocean Pier at Long Branch (Mariners' Museum, Virginia) Crustaceans demonstrate some curious distribution patterns that seem to depend on the season, substrate, salinity, water depth, and temperature. To study some of these patterns in local, inshore populations (And while fishing around for a thesis topic) I interviewed crabbers and recorded their catches between June 1979 and August 1980 at the fishing pier in Long Branch, New Jersey. Portions of the pier have endured or been rebuilt since the 1800's and in the past it was the destination of paddle-wheelers carrying New York City tourists to the shore. Its repeated destruction is often a footnote to major storms along the Jersey Coast. The current structure was built in 1911 and succeeded the Iron Pier (1881-1908); the Ocean Pier (1879-1881); the East End Excursion Pier - built in 1872 by Jay Gould (and collapsing a week later); and the Bath House Pier(1828), destroyed in a storm in August 1854.  (The Ocean Pier in 1879 from Frank Leslie's Illustrated Newspaper) Today the pier is an excellent study site because it attracts people throughout the year. It is a stationary sampling platform (except during large storms) and the sandy bottom is littered with quantities of rubble from periodic structural failures occurring during high seas. This "artificial reef" environment attracts a large number of crabs, fish, and of course, fishermen. Samples were taken weekly during the fishing season and at least once a month throughout the year. In most cases the crabbers cooperated enthusiastically, allowing their catch to be counted, weighed, and measured. Because of the height of the pier over the water, pull traps are used exclusively, and there is a fee charged for each of the two or three traps that the crabbers typically use. The recorded "catch" represents approximately 90 minutes of fishing time by crabbers, or if none were present, me Crabbers come primarily from urban counties of northern New Jersey (Hudson, Essex, Middlesex), and New York City. Ethnic minorities make up a substantial majority of the three to fifteen groups of crabbers that are usually present during the peaks of the May-through-December season. Crabbing is primarily an evening and weekend activity, and crabbing sorties average about six hours. Some crabbers stay through the night, since they pay for a 24-hour pass. In the warmer months, whole families often participate in the activities, at times taking home catches of several hundred crabs; enough to fill a plastic garbage can. Seasonal trends occur in the number of crabs caught, sex ratios, and the species that predominate at a given time. Catches recorded in order of abundance are: rock, calico, spider, blue and green crabs, as well as horseshoe "crabs," and a lobster. The yearly peak in numbers caught occurs in the fall and is followed by a smaller peak in the spring. Fall catches contain a fair number of calico crabs, but, like the spring, are dominated by rock crabs. Changes in species composition are most apparent when the water temperatures vary between 49°F and 65°F in spring and fall. Rock crabs are most abundant at around 50°F and the calico crabs are almost nonexistent in catches when the water temperature drops below 65°F in the fall. Two lulls occur - one in mid-winter around February and another in the early summer from June to July. The winter lull may simply represent a period of dormancy for the crabs (and crabbers) during the coldest part of the year; or more likely, movement offshore to avoid the severe inshore temperatures. The summer lull occurs as the last of the rock crabs depart and precedes the arrival of significant numbers of calico crabs. At this time the few crabs taken are spider crabs. Besides temperature and seasonal fluctuations, human activities may also affect the numbers of crabs around the pier. A significant recreational hook-and-line fishery exists here; concentrating on ling (red hake) and whiting (silver hake) in the spring and fall, and fluke (summer flounder) and bluefish in the summer. Presumably the large numbers of fish carcasses dropped off the pier tend to attract large numbers of scavengers.  Rock crab Rock Crab (Cancer irroratus): Rock crabs dominate the catch between October and May and comprise 63.4% of the yearly take at the pier. They are the common "winter" crab of the area and clearly begin to move offshore in May when the water temperatures rise above 65°F. They return in numbers only after the temperature begins to drop in October. The greatest concentration occurs in the fall, peaking between mid-October and late-November. At this time the water temperature drops to or below 50°F and the crabs' abundance corresponds with the arrival of ling and whiting, the two popular winter gamefishes. Good crabbing also occurs in the spring at similar temperature ranges, but not at the levels encountered in the fall. The average size of individual crabs increases noticeably in the early winter, with a peak in March, and then a drop in the spring. In both spring and fall, crabbers typically return up to half their catch because the crabs are too small to bother with. (There are no size regulations on any of the species except blue crabs). Males dominated the catches, out-numbering the females 26.5:1. Females appeared at the same time as males in the fall, but left sooner in the spring. Ovigerous females were collected only on April 18 and this may indicate that they spawn in deeper (cooler) water. There apparently is an off-shore movement of rock crabs in the summer and males outnumber females greatly, at least in this inshore area.  Calico crab Calico Crab (Ovalipes ocellatus): Calico (or Lady) crabs are the dominant summer crab, comprising 31.7 % of the yearly total and reaching a peak in mid-August. Generally, males outnumbered females (2.8:1), but not as dramatically as with the rock crabs; and on several occasions females outnumbered males. In the late summer total numbers dwindled rapidly and as the water temperature cooled to below 65°F they began to be replaced by the rock crabs. In the fall, females appeared to linger inshore later than the males, but like the rock crabs, they arrived simultaneously with the males at the beginning of their season. These fluctuations in availability are seasonally related and changes in sex ratios may indicate inshore mating activities. Ovigerous females were recorded in July, August, and September.  Spider crab Spider Crabs (Libinia emarginata): Although never abundant in the catches, spider crabs were collected in the summer and fall. They may be year-round residents but become inactive winter. They seem to be primarily nocturnal, appearing primarily in afternoon and evening catches. Ovigerous females were collected on June August 5. This edible crab, by far our largest, is never kept by the crabbers and is usually destroyed because it is considered a bait stealer.  Blue crab Blue Crabs (Callinectes sapidus): These highly sought after crabs were collected only on August 22. However, they were sighted on several calm evening late summer, swimming in the waters that are illuminated by the pier lights. Female crabs move downriver in estuaries in the late summer to spawn in higher salinity waters. Their appearance around the pier may demonstrate some degree of coastal dispersion. Green Crabs (Carcinus maenas): A single specimen was
collected in early Lobster (Homarus americanus): Although only one specimen was recorded they are probably fairly common around the pier. The debris-strewn bottom should provide suitable habitat and lobstermen routinely set pots within one half mile of the pier. Lobsters are also taken by divers from some of the nearby groins. Lobsters are cautious, nocturnal predators, and probably avoid the frequently retrieved crab traps, preying instead on other crustaceans and feeding leisurely on discarded fish carcasses. Horseshoe Crab (Limulus polyphemus): Horseshoe crabs were collected in the spring and fall, probably blundering into traps by accident. These common summer residents of our estuaries move to deeper water in the winter, and their appearance here signals their movements to-and-from nearby rivers. Specimens were young, judging from the lack of epibionts on their shells. Seasonal changes in crab distribution are apparent from the catch data. These changes are primarily related to seasonal temperature fluctuations and reflect an inshore/offshore movement of the crabs. Variations in sex ratios also exist, which may be related to spawning activities. Human activities, like the disposal of fish carcasses and the artificial-reef of accumulated debris, also affect crab abundance; and probably allow crabs to congregate in unusually high numbers - something we call "pier pressure". The pier serves as a source of food and recreation for many people. Although good numbers of crabs are removed, up to several hundred per day, they are for the most part an unexploited ocean resource in this area, and provide a cheap and abundant source of protein for anyone willing to fish for them..
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