Night Diving

light

Unlike ( or just like ) the Caribbean, diving in New Jersey is actually better at night in many ways. That's obviously not true if you are out to survey a shipwreck, but for inlet diving, there is no comparison. During the day, the day critters will be wide awake, and you won't be able to get near them, while the night critters will be down in their holes where you'll never see them.

At night, you can go right up to the sleeping day critters and pinch them, even the fish. Some even seem mesmerized by your light, which will also draw in many small invertebrates by itself. Meanwhile, the night critters will be out prowling around, including the king of all night critters, the lobster. And if you shut off the light and wave your hands vigorously, the bioluminescents will put on a show for you.

Actually, if you go down deep enough at sea, the difference between day and night becomes less pronounced as the surface light is filtered out by the somewhat-less-than-perfectly-clear Atlantic water. Basically, any time that the sun is not shining brightly high overhead is going to be nighttime on the bottom. For this reason, you should always carry a light, day or night.


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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