1 Jellyfish can survive in polluted water better than other fishes. That’s what happened off the coast of Namibia, once one of the world’s most productive fisheries. The ecological vacuum left by unrestrained fishing can allow jellyfish to expand their influence in marine ecosystems. Jellyfish are eaten by some fish, and jellyfish eat the same small zooplankton that fish do. And our lack of oversight of the fishing industry, which has removed more than 90% of the large fish from the seas, has depleted the predators of jellyfish as well as their competitors. And fields of polyps grow on those hard structures. When it finds a hard surface like a dock or a jetty to grow on, a single polyp can proliferate into a dozen or even more medusae. Rampant coastal development provides new habitat for a jellyfish stage called a polyp that looks like a sea anemone. Their gooey bodies clog machinery at power plants, halting operations. The fierce stings of these animals chase beach- goers out of the water. Some jellyfish, with their low metabolic rate due to their a-cellular jelly insides, can survive more easily there than fish, with their oxygen-guzzling muscled tissues. And as we wash pollution into our waters, we create low oxygen environments. In the twentieth century in the Adriatic Sea, moon jellies, pinkish with their characteristic four-leafed clover on top, were a rarity. That’s likely what happened off the coast of Italy, where gas platforms are thought to be the home for a new invasion of jellyfish. At the same time, our ship traffic transports animals to new places, and sometimes these exotics find home-like conditions where in the past those conditions would have been unsuitable. Because we burn fossil fuels, which release greenhouse gasses, not just the atmosphere but ocean waters are warming. And what they are seeing are changes produced by us here on land. They undulate in a primal rhythm, blinking open and closed like eyes that can peer into the soul of the sea. Diaphanous in form yet menacing in sting, jellyfish have a powerful capacity to capture our imagination. And all the while, alongside the heartbreak and horror, I kept thinking about a strange harbinger: jellyfish. Dozens died in the deluge, mostly by drowning. Toxic chemicals oozed from Superfund sites. Friends’ houses flooded -houses that had always been on dry land before. My Facebook feed filled with pleas for rescue from the rising waters. Then Harvey returned to land, dumping a catastrophic amount of rain on Houston. The heat armed the storm with a mighty arsenal of water vapor. Thermodynamic laws require that warmer air holds more water vapor. After Harvey left Port Aransas, it spun back into the Gulf of Mexico over record sea temperatures as great as 4 degrees Fahrenheit above normal. Harvey’s eye took direct aim at the University of Texas’ Marine Science Institute, flattening not just the facility itself, but priceless samples awaiting analysis. When it roared on land, it pummelled the towns of Rockport and Port Aransas, whose tawny beaches I’ve walked with my kids, pointing out the indigo sails of Portuguese man o’ war jellyfish. When Hurricane Harvey loomed off the coast of my home state of Texas, it seemed to fill the entire Gulf of Mexico. Direction (1 – 5) : Read the given passage carefully and answer the questions that follow.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |