April 7, 2011 -- Although it looks like something a whale coughed up, this chunky, brown mass is actually an invasive species of sea squirt.
Known as Didemnum vexillum, this species has been given a much more vivid nickname since its discovery in June 2010 in Sitka, Alaska: rock vomit.
As the name suggests, rock vomit likes to cling to rocks as well as piers, boat hulls and other hard surfaces. And, as you can see in the photo above, it really does look like vomit.
Using a remotely operated vehicle, or ROV, from NOAA's Auke Bay Laboratories (pictured below), researchers are trying to learn more about this sea squirt. The invasive species costs Alaskan aquaculture industries upwards of $500,000 annually.
Although rock vomit feeds on plankton and decaying plant matter, it can be deadly to other creatures. "It's a crazy organism," Linda Shaw, a NOAA Fisheries habitat biologist, said in a press release. "It smothers other creatures while producing acidic toxins that in turn prevent anything from growing on it. Rock vomit creates a type of barrier between groundfish and their food. It's been causing problems worldwide."