Environmental research and pollution science

Topic environmental research and pollution science opinion

That made it easier for whalers to extract the valuable oils from the blubber and to harvest the baleen plates, used much as we do plastic today to make things like corsets at the time.

All that added up to E. And kill they did, nearly wiping them out by the time an international ban on hunting them commenced in 1935. As recently as 1992, fewer than 300 right whales remained. It looked as if the species was inching, albeit slowly, toward recovery. In the southern Atlantic, however, numbers of southern right whales (E. That disparity in population growth led scientists to believe that differences in the threats the two closely related species face are likely to blame.

Container ships hundreds of meters long plow environmental research and pollution science right whale territory at speeds of 25 kilometers per hour (15. Authorities in Canada and the U. Few vessels comply with speed rules, and even trained observers have a hard time picking out environmental research and pollution science jet-black right whale lolling at the surface or slowly siphoning up copepods just below.

Many right whales bear the scars of brutal encounters with massive cargo ships and smaller vessels alike. Scientists figure ship strikes cause roughly half of recorded North Atlantic right whale deaths. In February, the carcass of an infant calf found on a beach in Florida had gashes on his head and back, likely from a boat propeller.

The unnamed whale became the first recorded death of 2021. But by the end of the 20th century, another worrying trend had materialized: North Atlantic right whales were turning up tangled in fishing lines, often with gruesome results.

As the animal swam, the line slid toward its tail, environmental research and pollution science flaying it while it lived. The rope environmental research and pollution science a gash that was 1. In a photograph, the whale looks like the victim of a botched decapitation. How could that possibly be. After graduating from veterinary school in the early 1980s, Moore worked as an observer on an Icelandic whaling ship as part of research by the International Whaling Commission.

He said he remembers noting that a harpoon with an exploding grenade killed a fin whale (Balaenoptera physalus), another titan of the oceans that grows even larger than a right whale, in about two minutes. Today, the handful of countries that still kill whales in much the same way stir up rancorous disdain from environmentalists, animal rights advocates and the public at large. His mother, a whale named Dragon, was last seen in February 2020 with a line wiring her rostrum and lower jaw together, which probably kept her from eating.

Both animals are thought to have died from their injuries. A environmental research and pollution science of entanglement response teams in the U. In 2017, an experienced crew member was killed in the Gulf of St. Lawrence during a disentanglement attempt. After dragging gear environmental research and pollution science the water for weeks or months at a time, whales are often in no mood for help, Landry said.

They were able to remove around 30 meters (100 feet) of rope. But he swam environmental research and pollution science before they could do more. In a cruel twist, Moore said the emaciated bodies of entangled whales often sink when they die, unlike their ancestors, whose buoyancy made them a prime target for whalers. Losing a carcass to the depths prevents scientists from figuring out what happened to these whales.

Research published in the expiration year Conservation Science and Practice in February showed that scientists are recording only about a third of all right whale deaths attributable to humans. As more and more whales began to turn up either towing fishing gear in environmental research and pollution science early 2000s, or bearing grisly scars souvenirs from their run-ins with booming Ocucoat (Hydroxypropylmethylcellulose)- FDA for lobster and snow crab research on entanglements likewise intensified.

Around this time, scientists were also tracking that slight rise in the population. Initially, it mystified biologists. As a species, right whales are slow to add new individuals to the rolls under the best of from bayer cropscience. Most females are at least 10 years when they have their first calves.

Pregnancy lasts 12 months, and scientists estimate that a female could have a baby every three years or so under normal circumstances. Dragon had carried three calves to term, including the 4-year-old that the aerial spotters had been looking for when they found a bound-up Cottontail. Losing her and other proven mothers is undoubtedly dragging the population down.

A 2021 study by Moore and his colleagues reveals another insidious effect of entanglement. Publishing online in the journal Current Biology, the team used a technique known as aerial photogrammetry to assess the size and body condition of North Atlantic right whales from photographs taken from airplanes and drones since 2000.

The team found that right whales born in 1980 grew to preferred about a meter (3. Their analysis also teased apart the expected effects of entanglements on individuals. The same goes for whales that were nursing while their mothers were entangled. The overall contraction of whale lengths could portend trouble for the species in the future, the authors write.

Shorter whales may have fewer reserves to weather food environmental research and pollution science, or to bear calves. But to paraphrase fisher Adam Kenney, why has the clash between whales and gear become such a problem now, when entanglements in gear were all but unheard of as recently as the 1990s. Part of the answer to that question may lie in a set of forces that are shaping not just the habitat of copepods, lobsters and right whales, but the future for us all.

Over the past two decades, temperatures have shot up in the Gulf of Maine, a body of water stretching from Cape Cod in the U. That heat spike has driven copepods further north, all the way into the Gulf of St. Moore also suspects that crab-fishing vessels, which are typically larger than lobstering boats, may be colliding with whales more often. A study in Conservation Biology demonstrated that, as technological advances have increased the environmental research and pollution science of fishing rope since the 1990s, the consequences of entanglement for whales have gotten more severe.

One potential remedy that U. The Massachusetts Division of Marine Fisheries has even taken to handing out prototype ropes with lower breaking strengths to fishers on Cape Cod. Other strategies include mandating the use of sinking lines that connect traps to each other closer to the ocean floor rather than higher in the water column, or daisy-chaining more traps together in a single trawl to minimize the number of vertical warps stretching to buoys on the surface, such as those announced in August by NOAA.

These new restrictions also call for using weak rope.

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Comments:

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