OWI gets some unusual calls almost every month. Last week, Cari from Sherwood, Oregon called to say that the little man-made pond in her backyard is inhabited by jellyfish this summer. We are used to people misidentifying wildlife and so I first assumed she was seeing amphibian egg masses. “No”, she said, “they are swimming!”. The photos she emailed of creatures floating in a wine glass were definitely jellyfish. So yesterday I went to visit the pond, and indeed, there are thousands of small jellies doing very well.
Back in the office, a few minutes of online research turned up the website FreshwaterJellyfish.org. The jellies in the Sherwood pond are almost certainly Craspedacusta sowerbii, a species native to China and introduced to North America, probably on ornamental aquatic plants. Small populations of the species mysteriously pop up almost anywhere in the US, usually in late summer. They often disappear at the end of the season, never to be seen again in the pond.
I’ve been studying Willamette Valley wildlife for almost 20 years and I can still be surprised by what turns up here. I’m not going to dismiss callers with the odd wildlife sightings quite so easily from now on. Thanks for the call Cari!
