8:34 p.m. - 2005-04-23
The Lovable Leech!
Hello! Happy Saturday to you all. Tonight I'm featuring an animal that I never thought would grace the Critter Corner: The Leech!
And, KB and I saw it in Richfield, otherwise known as the latter-day Eden of random wildlife.
As we entered the nature preserve Friday morning, we noticed a group of little kids, with some parents and a guide. Thinking nothing of it, we started on the trail. There, draped Dali-like over a branch, was a squirrel carcass! We were perplexed by the sight. K said, "Is it alive?" and I replied, "I don't think so...did it fall out of the tree?" We continued a few more steps, when we simultaneously saw a skunk sitting beneath a tree! We shrieked and I pulled K back! After a moment it became apparent that it was stuffed, and sure enough, further along the trail there was a raccoon pelt and a deer antler; the artifacts had been placed for the little kids to find!
We felt sheepish and relieved!
K spotted the leech as well. The lake at the preserve is bridged by several wooden piers, and we were crossing when K exclaimed, "What is THAT?" It was a gray, flattened worm, swimming in eel-like fashion. We decided it could only be a leech, and hoped that a big fish would jump up and eat it! Instead the leech (gracefully, I must admit) disappeared in the rushes.
I realized I did not know much about leeches, and did some research. Leeches are part of the Annelid family, which are segmented worms. The common earthworm is closely related. Euhirudinea is the Latin name for leeches.
Like earthworms, leeches have 34 segments, with a sucker on each end. While most leeches are totally aquatic, some are amphibic and there are land leeches in Southeast Asia and Australia! There are 700 to 1000 species of leeches.
Leeches have simple eyes, mostly to determine light and dark and perhaps to recognize some movement. They locate their prey through vibration, and as the victim approaches, by smell. There are some leeches that use sonar, and apparently land leeches detect increased levels of carbon dioxide as they track their prey!
While some leeches are sanguivorous (blood suckers!) others eat their prey whole, or hunt down fish and amphibian eggs, insect larvae, worms and snails. These leeches hide and wait for prey to approach, then latch on with their sucker mouth and insert a proboscis, with which they suck the victim dry.
There are groups of leeches with two jaws, who leave a V-shaped bite, and some with three jaws, who leave a Y-shaped wound.
My boyfriend informed me today that he always wanted to have an aquarium with leeches in it, as they look so cool when they swim. Then he wondered what one would use to feed the captive Annelids. Apparently live snails make good food, or one could put a frog or turtle in the tank for a while so the leeches could suck on it? Eeeeeewwwww. I guess hamburger is also a possible food source. Thankfully leeches don't need to eat often!
Leeches are associated with medieval medicine, and indeed have medicinal properties now. Decorsin is a chemical released by North American leeches to prevent "platelet aggregation", or blood clotting.
I was thinking about leeches, and how I really don't rationcinate about them that often. Perhaps when remembering the movie "The Great Outdoors", or as R informed me today, "Stand by Me" also has a leech moment. I guess one can think of them as a good fish bait. One of the reasons leeches aren't frequently encountered is that they're mostly nocturnal, and live in shadowed parts of lakes and rivers, or under logs and debris.
Isn't it great that K and I saw one yesterday!?
In the love department, leeches are the ultimate partner...to themselves! They have both sperm sacks and a pair of egg sacks. Some species have a gonopore, which I assume is a sexual opening. Others have a penis and a vagina. Apparently leeches can pass the sperm sacks through the skin into another leech, or drop it off into the pore. I'm simultaneously confused and aroused?
Whew, sounds like high school!
Leeches are good parents. After fertilization occurs, the leech produces a cocoon filled with eggs, which it either attaches to a fixed object or to its own body. The parent later brings the hatchlings food.
Check out http://www.invertebrate.ws/leech/ for details, and pictures!
In the food chain, leeches are an important meal for amphibians, fish, and insect larvae.
I hope this entry has been informative! To me it's exciting to learn about a creature I just haven't encountered much. Which probably is a good thing!
Suck, bite and suck,
Wendell!
