![]() Breitburg has sampled the Patuxent since 1992, creating a data set that complements a long-term inventory started in the 1960s by the late fisheries biologist Dave Cargo, of the University of Maryland Center for Environmental Science (UMCES) Chesapeake Biological Laboratory in Solomons, Maryland. In the saltier Patuxent River, located roughly 40 miles south of the Rhode, the decline in sea nettles has been unmistakable. She has only just begun sampling this river for gelatinous creatures so it is hard to tell if the missing nettles, Chrysaora quinquecirrha, and bountiful comb jellies or ctenophores (pronounced teen-o-fors), Mnemiopsis leidyi, in the Rhode are part of a more ominous story that has been steadily unfolding two tributaries to the south. ![]() But the 12-foot-long Neuston net pulled by the bigger boat filters huge volumes of water over and over again, with the same result.no nettles.Ībsent nettles in the Rhode might not be so unusual, Breitburg explains, especially since the river's salinity is low and these animals gravitate toward saltier waters. Breitburg wants to verify that the smaller net pulled by the skiff was not simply missing the larger nettles. Today, Breitburg, an estuarine ecologist at the Smithsonian Environmental Research Center (SERC) in Edgewater, Maryland, along with her graduate student and post-doctoral fellow, is aboard SERC's 42-foot R/V Saxatilis, sampling for nettles and comb jellies again, using a bigger net. ![]() Each week yielded the same result.no nettles. ![]() "We haven't seen a single sea nettle in the area this season."Īll summer, Breitburg's group had been using a small 16-foot skiff to sample the Rhode for sea nettles, the stinging jellyfish well known to anyone who has swum in the Chesapeake, and comb jellies, their non-stinging cousins. "Only comb jellies again," Breitburg says, shaking her head. As the boat cruises ahead to the next station, she turns back to the cylinder and pours another sample into the measuring cup. Standing quickly, she flings the contents of the sieve overboard - gelatinous animals flying through the air before hitting the water. Breitburg swiftly sorts through the organisms, which range in size from fingernail to nearly whole hand, surveying the catch. Like raw eggs hitting cookie batter, gelatinous animals fall by the hundreds onto the sieve. Then she empties the cupful into a large, circular metal sieve.īlop, blop, splat. She pours some of the gelatinous contents into a giant measuring cup, pausing to record the volume. The lead scientist, Denise Breitburg, kneels and carefully unscrews the large cylinder at the base of the net - the so-called cod-end that traps whatever is floating in the water. From the deck of the research boat bobbing in the Rhode River this summer morning, two scientists and the captain lean out and swing it aboard, soaking their shirts as they lower the net onto the deck. The plankton net abruptly breaks the water's surface and dangles precariously from the winch, a long porous stocking trailing behind a 2-foot-square metal frame, dripping brackish water. Their loss, coupled with the decline of grasses and oysters in the 1970s and 1980s, caused the Bay to lose much of its resilience. Forests and wetlands trap sediments and help slow the flow of pollutants into the Bay.
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