There is something strange happening off the coast of the Pacific Northwest. Fishermen from Oregon to Alaska are reporting massive increases in populations of bizarre creatures, and they are left wondering why are their numbers growing, and what effect will they have on the marine ecosystems the fishermen depend on. This mystery also has marine biologists scratching their heads.
The first reports of larger than usual numbers of these strange creatures began in 2014. The numbers escalated in 2015 and 2016, and now they are at almost unprecedented levels.
The bizarre animals are called pyrosomes, or more commonly, sea pickles. These tiny planktonic creatures are typically only a few millimeters long, but they mass together into colonies that can grow to be several meters in length. They share a common outer sheath and are remarkable for their bioluminescence.
Because they are planktonic, their distribution is largely the result of ocean currents and tides, however they are able to move locally through a sort of jet propulsion. They will intake water and then eject it rapidly under pressure, enabling it to move in the opposite direction.
Sea pickles eat microscopic plants by siphoning in water through a mesh membrane in the outer sheath.
Olivia Blondheim is a student at the University of Oregon, and spoke with the Guardian about the proliferation of these creatures.
“Right now we are scrambling to learn as much as possible while we have the opportunity,” she said. “If we continue to see this many, what impact will it have on the ecosystems here, and what economic impact on the fisheries? There are so many unknowns at this point, it really is a remarkable bloom. One of the things we are figuring out is ‘have these guys been off the coast and we haven’t seen them? Are they moving inshore for a different reason?’”
Blondheim continued, saying “There were reports of some pyrosomes in 2014, and a few more in 2015 but this year there has been an unprecedented, insane amount [stretching] as far as the eye can see.”
Dr Lisa-Ann Gershwin is a fellow at the Commonwealth Scientific and Industrial Research Organization in Australia. She says “Because they aren’t wanted, and people really aren’t used to seeing them, they really do impact fisheries and catch a lot of attention. In the case of these pyrosomes, I don’t think anyone is quite sure what has led to this bloom. it is unusual. There is every possibility it is a natural phenomenon, but an abundance this gobsmackingly big also suggests there may be something behind it that is not natural in origin.”
Might it be that this is a warning sign of climate change?is it possible that colder waters are becoming more habitable for warm water species, thus driving their ranges in search of new food sources/ or could it be that the ocean currents themselves are being redirected by climate change?
Have you ever seen such a strange creature? What do you think is causing these massive blooms?