Leeches

leech

Macrobdella spp.

Size: to 10"

Habitat: aquatic

Notes: It's not a nice thought, but there are leeches in our freshwaters, and in marine habitats as well. The species shown is one of the largest and most attractive, if you can say such a thing. It feeds exclusively on vertebrate blood - a good reason to wear a wetsuit, although I've never encountered one. Leeches are actually worms, not insects, but ...


algae
A garden of green and brown algae grows on a shallow rock. Enteromorpha (Hollow Green Weed) and Fucus (Rockweed)

In our waters, plants and algae are found only in shallow water where sufficient light can penetrate for photosynthesis. It would be unusual to find algae below 10-20 ft, so our wrecks and reefs, despite the profusion of attached organisms, are actually devoid of plant life! Of course, that is completely neglecting the microscopic algal plankton that is so profuse in our waters and so lacking in the clear water of the tropics.