It’s no fluke: Fish populations are on the move, chasing cooler marine temperatures. At Rutgers, scientists track their alarming migrations.
August 11, 2017 — In Malin Pinsky’s lab, they keep the unicorn blood in the fridge. It sits alongside dozens of small, white boxes, each containing a snippet of fin or other tissue from the clownfish and summer flounder that, together, may help Pinsky and his colleagues determine the answer to a critical question about the world’s changing oceans. In fact, the unicorn blood—so dubbed by lab manager Michelle Stuart because, Pinsky explains, “it’s expensive and it works magic”—is actually a stew of enzymes used to purify DNA from those fish samples.
The DNA helps Pinsky and his team at Rutgers University in New Brunswick track the movement of fish species over time. What they are finding is likely to have major implications for the commercial and recreational fishing industries in New Jersey and around the world.
For decades, scientists have observed a northward shift in the ranges of many land-based animals in response to a warming climate, among them birds and butterflies. In addition, some mountain-dwelling species, like the pika, a cousin of the rabbit native to the Western United States, have moved to higher altitudes, chasing the cooler temperatures to which they have adapted over millions of years of evolution. Among these observations are scattered reports of the same thing happening in warming ocean waters.
As a marine biologist, Pinsky had read the reports. Concerned about how widespread the changes might be, he and his colleagues ran the first stage of an ongoing research project from 2011 to 2013. The results were startling. “Not only are many species of marine animals, from cod to flounder to lobster, moving to new locations,” says Pinsky, “but it’s happening very rapidly, and it’s affecting a wide range of fisheries, both commercial and recreational.”
Analyzing data collected annually by the National Marine Fisheries Service and its partners, Pinsky’s lab launched the website OceanAdapt, which charts the changing ranges of a wide variety of marine species, regionally and nationally. The site’s graphs depict changes in latitude and sea depth. On a species-by-species basis, those changes are not particularly striking; it’s long been known that fish move around a lot from year to year. But when considering the marine life community as a whole, one observes an indisputable trend northward and downward (to greater depths).