Monday, April 11, 2011

Apple snail studies

Apple snail studies, originally uploaded by Elizabeth Smith.

This empty snail shell was found in a ditch near some woods in town, and although I know it’s an apple snail, I’m not sure which one it is. Florida has one native species of apple snail,  and several invasive species –causing concern among biologists and farmers. The invasive species are probably released from home aquariums. Apple snails are popular in the aquarium trade because they’re attractive and are effective tank cleaners.

Apple snails are the largest freshwater snails on earth; the snail shell I sketched is about 3 inches long! The fact I find most interesting about these snails is their breathing structures. Some snails have gills, and some have lungs, while some (like the apple snail) have both gills AND lungs. Having both breathing arrangements allows them to successfully weather our wet and dry seasons. The Florida apple snail is the main food for the limpkin and the Florida snail kite, an endangered species. No wonder biologists are concerned over the nonnative invaders.

I sketched this shell from several different angles with a Sakura Micron Pigma sepia color pen with an 01 point. Lately, I’ve found myself sketching directly with ink more often, bypassing the preliminary pencil lines. It’s very freeing (once you get over the initial *yikes* factor), and I find that with a fine point and hatch lines, my false starts fade into the rest of the drawing. Anyway, I hope you get a more immediate connection to my subject with this method – unfortunately, I find that the more detail I add, the tighter my drawing gets. Some days I find it very difficult to loosen up my drawing style.  There's always next time!

If you’re interested in reading more about these snails, please visit these additional links:

Technical Bulletin on Apple Snails from the Commissioner of Agriculture (PDF)

USGS (United States Geologic Survey), about the Florida apple snail (PDF).

You can click on the caption of the top image to visit it on my Flickr photostream.