Worms are the kind of creatures that probably don't cross your mind until you come across one when digging in your garden. But Tampa Bay is crawling with them - literally.
One study of Tampa Bay, cited in the Introduction to Marine Biology text book, found 13,425 of the critters per square meter in the sediment of the bay's bottom. This abundance of marine worms came from 37 different species.
Granted, these aren't your garden variety earthworms. While both are from the phylum annelids, the worms you'll find in Tampa Bay are from the class polychaetes, and can be found in marine environments worldwide. Polychaetes are notable for their many bristles, and thousands of species can be found worldwide. While some polychaetes live in burrows or tubes, others move freely on top of the sediment.
In Tampa Bay alone there are more than 500 species of annelids, or segmented worms. But just five species account for more than 25% of the segmented worms collected by scientists in Tampa Bay.
For the true marine worm aficionado, the most common type of polychaete is Monticellina cf. dorsobranchialis, and is found in silty sediments, particularly in Hillsborough Bay and bay tributaries. This species is present in more than one-third of benthic (sediment) samples collected in Tampa Bay. Monticellina have two large feeding tentacles, which they use to gather up food from the surface of the sediment.
The next most common is called Streblospio cf. gynobranchiata, and populates areas with lower salinity, such as the rivers that flow into the bay.
Ranking third in prevalence is Laeonereis culveri, found in moderately brackish waters, like McKay Bay and the lower reaches of bay tributaries, as well as the Big Bend and Apollo Beach areas.
You're also likely to find Prionospio perkinsi and Paraprionospio pinnata spread throughout Tampa Bay because they are able to tolerate a wide range of water conditions.
Polychaetes are among the most important organisms in Tampa Bay. Not only do they eat organic material in the sediment, the worms themselves serve as tasty morsels for other sea creatures, like fish, shellfish and shore birds, making them a vital link in the marine food web.
Special Thanks to Dave Karlen, benthic ecologist with the Environmental Protection Commission of Hillsborough County for his help with this article.