Nudibranchs

Nudibranchs

Idulia spp, Coryphella spp, others

Size: 1/2 " to 4"

Nudibranchs or Sea Slugs are not worms but shell-less gastropod mollusks, related to garden slugs. Their closest relatives here are planktonic Sea Butterflies. Some types of nudibranchs, including those shown here, assimilate the functioning stinging cells of their food, and should not be handled for this reason.

Nudibranchs

Red-Gilled nudibranchs feeding on hydroids, with which they are often found. They grow to 2 inches.

Nudibranchs
Maned Nudibranch - Aeolidia papillosa
Maned Nudibranch

The Maned Nudibranch feeds chiefly on sea anemones, with a preference for the Frilled Anemone. The animal tends to take on the color of the anemones on which it preys. The Maned Nudibranch is 4" long, 1-1/2" wide, thick, and stubby. Its coloration is whitish, gray, or tawny-brown, with pale speckles. The nudibranch's back is covered with hundreds of slender, finger-like projections with a bare area down the midline. It has 2 pairs of antennae on a squarish head and its rear end is tapered to a blunt point.

Maned Nudibranch

compass

A compass is the most basic and inexpensive piece of navigational equipment and should be bought at the same time as the rest of your gauges.

In a beach or inlet dive your compass is your single most important tool - it tells you which direction is the shore. When wreck diving, a compass is useless if you don't look at it until you're lost. Take a bearing as soon as you hit the bottom, just in case. In a boat dive, directions such as "turn right from the anchor" can often steer you in the opposite direction, if the current reverses and pulls the boat around to the other side. Compass bearings are much more reliable.