First published in Landings, August, 2014.
Jellyfish have been abundant this summer along the coast of Maine, but no one seems to know why. One theory is that climate change and warmer water temperatures have caused the increase in jellies in Maine. Lower oxygen levels caused by runoff from land or overfishing may be to blame as well. 2012 was another big year for jellyfish, and a year marked by unusually high water temperatures in the Gulf of Maine.But there is no research to support or refute these theories.
A June article in the Portland Press Herald noted that there are no experts or good data on jellyfish in Maine. However, Nick Record of the Bigelow Laboratory for Ocean Sciences in East Boothbay has decided to change that. He has been documenting the reported species seen in Maine this year and hopes in the future to create a predictive model.
“There’s something out there called the ‘Jelly Oceans Hypothesis,’” said Record, in a recent interview on Maine Public Radio. “Some scientists have hypothesized that we’re shifting toward an ocean that’s dominated more by gelatinous species rather than things like fish. And there are a variety of causes, from over-fishing, to low oxygen, things related to pollution, but that hypothesis is debated.”Jellyfish are not actually fish so scientists call them jellies to avoid confusion. There are two groups of jellies – ctenophores and cnidarians. Cnidarians are the true jellies; all have specialized stinging cells. This group of jellies includes Portuguese man-o-war, sea wasps, anemones, corals, and moon and lion’s mane jellies. The latter are two of the three jellies found in Maine. Lion’s mane jellies are a northern species, native to the Arctic, northern Atlantic and northern Pacific oceans. Moon jellies are found throughout the East coast.
Moon and lion’s mane jellies have stinging cells in their tentacles, which can cause stings that are painful. The standard treatment for a sting is to flood the area with vinegar or isopropyl alcohol for ten minutes or more, then make a paste of baking soda and water and apply that to the area.
Comb jellies, the third kind of jelly found in Maine, are ctenophores, so named for the hair-like structures called cilia on their bodies that beat in unison allowing the jelly to swim. There are 50 known species of ctenophores and they are found in almost all marine environments.
Jellies have no backbone, brain, heart, real digestive system, complex eyes, or respiratory system, and are 95% water, yet they are still good predators. They are considered plankton because although they can swim, they primarily drift with the currents. They capture small zooplankton in their tentacles as they float through the water. Some bigger jellies prey upon fish, stunning them with their stinging cells. Jellies also become prey themselves as a favored food of sea turtles and other jellies.
Record has decided that after two summers of numerous jellies showing up in Maine it’s time to keep track of the gelatinous visitors. This summer he began building a library of the species spotted here and hopes to create predictive models that might tell us when to expect jelly blooms like the one that began this June.