Fish Traps

fish trap
A fixed fish trap. The curtain nets stretch from surface to bottom, and the fish are funneled into holding areas.

Fish traps are only practical in shallow water. They have the advantage of keeping both the targeted catch and the bycatch alive ( unless a shark gets in ! ) You can still see a few fish traps in use in Raritan Bay, where they are built around fixed pilings rather than buoys and anchors as shown here. In years past, shore-based trawling or "haul seining" was also practiced in the bay, where a net would be deployed off the beach by a small boat, and drawn in by donkeys or trucks.

haul seine

Haul Seining

An estimated 50 tons of spawning Striped Bass is taken in a single net on a Virginia beach in 1972. This type of fishing would be completely illegal today.

The main fishery in Raritan Bay has always been Mossbunker.

A similar type of fixed fish trap is the gill net, which uses a specific-size mesh to trap a certain size of fish. When the fish tries to swim through the net, only its head fits. Then when it tries to back away, it becomes ensnared by its gill covers. This kind of gill netting is fairly specific, as smaller fish pass through the net unharmed, and bigger ones don't get caught in the mesh. A terrible variation of this is drift-netting, described above.


Jellyfishes
Moon Jellies Aurelia aurita (left) and
Red Jelly Cyanea capillata (right)

Jellyfishes are free-swimming relatives of corals, anemones, and hydroids. In fact, in many cases, they are the same species, just in a different stage of life! Not all medusas ( as jellyfishes are called ) have a corresponding polyp stage, and likewise, not all polyps have a corresponding medusa stage, but most alternate generations in each form. Small jellies ( up to 1" across ) are most likely the medusa stage of some hydroid, while large jellies are usually the dominant stage of a species in which the polyp stage is almost absent. Even anemones have a periodic medusa stage, although it is infrequently observed.

Although jellyfish can swim slowly, they are largely at the mercy of the tides and currents, and at times large numbers are concentrated into bays and may be stranded on beaches.

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