Lobsters in Maine are bigger and there are more of them, the result of the last decade being the warmest ever on record in the Gulf of Maine. But a surfeit of good-sized lobsters has had unforeseen results. Not only are lobstermen seeing their profits decline as prices fall to levels last seen in the Great Depression, but lobsters are eating each other.
Noah Oppenheim, a graduate student in marine biology at the University of Maine, made the grisly discovery after sending down juvenile lobsters in traps outfitted with waterproof infrared cameras. Similar experiments conducted in the 1990s had found that, along with lobster traps, the main cause of lobster deaths was fish feeding on them. Cod and other bottom-dwelling fish (flounder and eels), crabs and seals all eat lobsters.
After Oppenheim’s recent experiments found that, 90 percent of the time, adult lobsters were eating the juvenile ones, a phenomenon not previously documented in the wild.
Lobsters can be said to be “opportunists” who will also eat another lobster if given the chance. They have been known to eat each other in captivity; the practice of putting rubber bands on their claws is more to protect them from each other. According to Oppenheim, this amount of lobster cannibalism he has recorded is unprecedented among lobsters in the wild.
A sort of perfect storm of events has created this situation. While the century average for gulf water temperatures was 47.6 degrees Fahrenheit, it has now risen to 50.7 degrees in just a few decades. As Oppenheim explains to James West of Climate Desk, the warmer water has led to lobsters reproducing more quickly, having larger broods and growing more rapidly.
At the same time, cod, who are the natural predators of lobsters, have virtually disappeared from the Gulf of Maine, the result of overfishing; the cod population is at only 18 percent of the level that scientists estimate is needed to be healthy. Meanwhile, there is also an abundance of bait (fish such as herring) left in the thousands of lobster traps that smaller lobsters are able to escape from.
Ironically, the abundance of lobsters has not been a boon to those fishing the Gulf of Maine’s waters. While as recently as 1987 lobsters only comprised 8.6 percent of Maine’s seafood catch, they now make up 40 percent of it — that is, the state’s fishing industry has become increasingly dependent on lobsters. At the same time, lobstermen are seeing their profits shrink dangerously as the abundance of lobsters drives down prices. As a result of climate change heating up Maine’s waters and the overfishing to meet rising demand for seafood, Maine’s fishing industry can be said to be cannibalizing itself.
Cannibalism has also been found among other animals as a result of the the recent rapid changes in global temperatures. Reports of adult polar bears killing and eating cubs in Canada have been said to be occurring more due to changes in the food supply. As a result of the melting of the sea ice, polar bears are spending more time on land and less on the ice where they can hunt seals; they are therefore turning to other sources of foodd.
Along with reports that endangered species may be turning to mating with siblings as their numbers have declined drastically due to habitat loss, the rise in lobster cannibalism that Oppenheim has found is yet another example of how nature is being transformed — too often in some highly worrisome ways — as a result of human activity. Genetically modified wheat and other plants have been called “Frankenfruit,” but they are hardly the only monstrosities resulting from climate change.
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