Global Warming Is Hitting Ocean Species Hardest, Including Fish Relied on for Food

Global Warming Is Hitting Ocean Species Hardest, Including Fish Relied on for Food

SOURCE: Inside Climate News DATE: April 24, 2019 SNIP: Sea creatures, especially those that live in shallower water near the coasts, are much more vulnerable to global warming than land animals, new research shows. The scientists found that local populations of marine animals are disappearing at double the rate of land-based species. That’s because marine animals like fish, crabs and lobster are already more likely to be living near the threshold of life-threatening temperatures, and because in the ocean, there are fewer places to hide from extreme heat, said Malin Pinsky, lead author of a new study published Wednesday in the journal Nature. “These results are stunning, in part because the impacts of climate change on ocean life were virtually ignored just a decade ago,” said Pinsky, an ocean researcher at Rutgers University. The study took a close look at cold-blooded marine species whose body temperatures are dependent on their surroundings. “We already know terrestrial species are highly vulnerable to climate change,” he said, “and now we see that marine species are even more vulnerable.” “We’re heading into uncharted territories. We’re already seeing species disappear from places they’ve been for generations and longer,” Pinsky said. For example, damselfish and cardinalfish, two small species that live on coral reefs, already live near their thermal limits and have started to disappear from some areas, which contributes to the overall decline of coral reef health. Of the marine species they studied, 56 percent experienced a range contraction due to global warming, compared to 27 percent of the land species. Fish species won’t be able to evolve fast enough to keep up, so...
Turtles’ absence from Nicaraguan stronghold raises alarm for future

Turtles’ absence from Nicaraguan stronghold raises alarm for future

SOURCE: The Guardian DATE: April 15, 2019 SNIP: Every year, from November through March, leatherback sea turtles arrive to the secluded shores of the Río Escalante Chacocente wildlife reserve on Nicaragua’s Pacific coast to lay their eggs. Though leatherback nesting habits vary, Chacocente has been a reliable egg-laying site for as long as conservationists have collected nesting data. But this year, not a single leatherback came to Chacocente, and conservation groups in Costa Rica and Mexico, have recorded declines in sightings of the huge turtles. Leatherback populations face threats from human activity, and the eastern Pacific population of leatherbacks is classified as critically endangered. Both legal and illegal fishing have helped drive the decline, as well as egg poaching. In Central America sea turtle eggs are considered a delicacy and in some communities are held to be an aphrodisiac. While conservation efforts have focused on countering human harvesting of turtles, there is also growing evidence that warming temperatures could play a role in the population decline. In leatherbacks and other species of sea turtles, the sex of a turtle hatchling is determined by the temperature of the sand where the egg incubated. Higher temperatures produce female eggs, and scientists suspect that a large portion of sea turtle hatchlings are now...
Climate Change Threat to Dolphins’ Survival

Climate Change Threat to Dolphins’ Survival

SOURCE: University of Zurich DATE: April 1, 2019 SNIP: An unprecedented marine heatwave had long-lasting negative impacts on both survival and birth rates on the iconic dolphin population in Shark Bay, Western Australia. Researchers at UZH have now documented that climate change may have more far-reaching consequences for the conservation of marine mammals than previously thought. Shark Bay in Western Australia in early 2011: A heatwave causes the water temperatures to rise to more than four degrees above the annual average. The extended period caused a substantial loss of seagrass, which drives the Shark Bay ecosystem, in this coastal area, a UNESCO world heritage site. Researchers from UZH have now investigated how this environmental damage has affected survival and reproduction of dolphins. They used long-term data on hundreds of animals collected over a ten-year period from 2007 to 2017. Their analyses revealed that the dolphins’ survival rate had fallen by 12 percent following the heatwave of 2011. Moreover, female dolphins were giving birth to fewer calves – a phenomenon that lasted at least until 2017. “The extent of the negative influence of the heatwave surprised us,” says Sonja Wild, former PhD candidate at the University of Leeds and first author of the study. “It is particularly unusual that the reproductive success of females appears to have not returned to normal levels, even after six...
Heatwaves sweeping oceans ‘like wildfires’, scientists reveal

Heatwaves sweeping oceans ‘like wildfires’, scientists reveal

SOURCE: The Guardian DATE: March 4, 2019 SNIP: The number of heatwaves affecting the planet’s oceans has increased sharply, scientists have revealed, killing swathes of sea-life like “wildfires that take out huge areas of forest”. Global warming is gradually increasing the average temperature of the oceans, but the new research is the first systematic global analysis of ocean heatwaves, when temperatures reach extremes for five days or more. The research found heatwaves are becoming more frequent, prolonged and severe, with the number of heatwave days tripling in the last couple of years studied. In the longer term, the number of heatwave days jumped by more than 50% in the 30 years to 2016, compared with the period of 1925 to 1954. As heatwaves have increased, kelp forests, seagrass meadows and coral reefs have been lost. These foundation species are critical to life in the ocean. They provide shelter and food to many others, but have been hit on coasts from California to Australia to...
Climate change is cooking salmon in the Pacific Northwest

Climate change is cooking salmon in the Pacific Northwest

SOURCE: Popular Science DATE: February 8, 2019 SNIP: The Tulalip Indian Reservation sits on the east side of the Puget Sound, about 40 miles north of Seattle, Washington, where the change in seasons is marked by the arrival and departure of salmon. At the heart of the reservation is Tulalip Bay, where salmon return every spring and fall before swimming upstream to spawn. But it has become increasingly difficult for the Tulalip people to care for the salmon. Since the 1980s, wild Pacific salmon have faced a sharp decline due to overfishing, habitat loss and pollution, leaving several local populations threatened or endangered. Now, climate change is further imperiling the fish. Recent summers in the Pacific Northwest have been beset by record heat, and higher water temperatures are killing the adult salmon before they can reproduce. Pacific Salmon are anadromous, meaning they spend their juvenile years in freshwater streams and rivers, before moving on to estuaries, and then, in their adult years, the open ocean. Adults return to the streams where they were born at the end of their lives to spawn. Extreme heat has made this journey particularly treacherous. The Washington Department of Fish and Game does not track the number of fish who make it to spawning grounds but die before they can reproduce. However, hatchery workers say they seen have more and more adult fish perish in stream beds before they can spawn. It’s not just heat that is threatening fish. Dwindling winter snowpack has deprived the rivers and streams where salmon spawn of a key source of water. “With lower water [levels] and higher water...