One of the reasons the Marine Biological Laboratory was built in Woods Hole is because of the stunning amount of biodiversity in the local wildlife. In our latest #MBLSciShoots digital learning lesson, Marine Resources Center Director Dave Remsen takes a look at two of those local species—the American slipper limpet (Crepidula fornicata) and the parchment worm (Chaetopterus).
Introduction to Chaetopterus | Bishop Museum, University of Hawaii
Questions from the Audience
Is it possible to see the parchment worm sleeves while snorkeling, or are they far enough down that we would need to SCUBA?
It is possible to see the chimneys (sleeves) at snorkeling depth. Elaine Seaver finds them in Florida in very shallow water. We see them in local harbors among Eel grass meadows in less than six feet of water. The problem for us is that these meadows make it difficult to collect the worms because the burrows are entangled in the roots and rhizomes of the eel grass. Our collecting locations of deeper, softer mud bottoms makes the collections much less invasive.
Are either of these species invasive or threatened by invasive species?
Crepidula fornicata is a known invasive species. It is native to our New England waters but is invasive in Western Europe and the Mediterranean. See this summary from the Invasive species specialist group of the IUCN. In France, Crepidula competes with local oyster farming efforts. Crepidula locally seem to not be negatively impacted by invasive species. In fact, they appear to have increased in abundance, perhaps in response to ecological changes brought on by invasives or other human-mediated activities.
I don’t know of any direct invasive threats to Chaetopterus in our local waters but I did find some references to our local Chaetopterus species, variopedatus, being invasive in New Zealand of all places. Take a look at this page. Note that it isn’t absolutely verified this is variopedatus. There doesn’t appear to be much literature on this so this needs some more investigation. There is also an invasive Chaetopterus in Hawaii but the species is not identified.
Do you find a lot of parchment worm tubes in one place or are they generally isolated?
This varies according to habitat. They can be scattered irregularly in many locations, such as coastal eel grass meadows where there seems to be no pattern to their light distribution. In areas where we collect the in Buzzards Bay they may be relatively more dense with tubes. A dense area might have 1-2 tubes per square meter.
How do parchment worms reproduce if they’re so separate from each other?
Parchment worms remain isolated in their burrows for their entire lives. To facilitate reproduction, the female releases a chemical, called a pheromone, that signal males to shed sperm into the surrounding waters. This causes the female to shed eggs, resulting in fertilization. Learn more!
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