CO2 Benefits the “Rats and Cockroaches” of Marine World
Ocean acidification may be driving a cascade of changes that drains marine biodiversity
By Adam Aton, ClimateWire on July 7, 2017
Beneath the waves, swelling levels of carbon dioxide could be boosting some species to ecological dominance while dooming others.
A study published yesterday in Current Biology suggests ocean acidification is driving a cascading set of behavioral and environmental changes that drains oceans’ biodiversity. Niche species and intermediate predators suffer at the expense of a handful of aggressive species.
Sea-level rise and coral bleaching often dominate discussions about how climate change affects the ocean, but a host of more subtle—and harder to research—trends also play a role in reshaping the world’s marine ecosystems. Among the most pressing questions is how fish react to rising levels of CO2, said Tom Bigford, policy director at the American Fisheries Society.
“The hurdles for behavioral changes are far lower than the hurdles for life and death,” said Bigford, who worked with fish habitats at NOAA for more than three decades.
Now, for the first time, researchers from the University of Adelaide in South Australia have cataloged the changing ways marine species interact with each other.
For three years, they observed marine environments near undersea volcanic vents where CO2 levels are high—providing a window into the future acidity of ocean water—along with adjacent areas of normal acidity. They also conducted behavioral experiments on fish from the different zones to test their responses to food and habitat competition.
Receding kelp means less habitat for intermediate predators, with about half as many near the volcanic vents.
But the acidified conditions proved to be a boon to what the researchers called “the marine equivalent to rats and cockroaches”—small fish with low commercial or culinary value.
Snails and small crustaceans can flourish in high-CO2 conditions, providing plenty of prey for those small fish. And their high risk-taking behavior and competitive strength, coupled with the collapse of predator populations, allowed them to more than double their population.
In water with higher CO2, the dominant species were willing to adapt to riskier habitats, preferring bare surfaces instead of turf while subordinate species were nearby.
Mimicked predator attacks also showed the dominant species adopted riskier behavior in higher-acidity water, fleeing shorter distances than the fish in water with normal acidity. Subordinate species showed no change.
Rare and specialist species are the most vulnerable to climate change, even though they “contribute disproportionately to [ecosystems’] functional diversity,” the researchers wrote.
To counter that diversity loss, the researchers suggested stronger fishing protections for predators.
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Five oil and gas companies has asked the Trump administration to allow them to conduct offshore seismic testing which could separate young whales from their mothers or prevent dolphins from feeding. Tell officials handling this proposal that this is a bad deal for wildlife and America’s eastern seaboard.
A famous surfer has proposed on social media that France’s government should cull sharks daily to resolve the issue of an increase in shark attacks. Culling is cruel and ineffective and should not be promoted by an influential public figure. Tell this surfer that sharks belong in the ocean by signing this petition.
15,000 lives have been killed by sharks nets!
One Green Planet
Imagine you’re taking a day to relax on the beach. There’s a warm, gentle breeze rustling your voluminous, freshly-washed hair –you pretty much look like a super model. You reach for a chip and hear the crinkle of cellophane mixing with the hypnotic sounds of the surf crash against the beach. As the sun presses down on your oiled bronzing skin, you grab your water bottle feel the cool plastic, slick from perspiration, beneath your palm as you take a swig of the ice cold water. Now imagine a 37-foot sperm whale washing up dead at your feet on the beach. Back to reality . . .
A juvenile sperm whale recently washed up dead on a beach of the Davao Gulf just outside of a resort in Samal, located in the Philippines. The autopsy revealed that the whale had, “large amounts of plastic trash, fishing nets, hooks and even a piece of coco lumber in its stomach,” and experts believe the cause of death for this majestic creature was choking on plastic. Seems a little crazy that such a mammoth whale could be taken down by plastic, but this is not the first time this has happened. Of the 54 whale deaths that have been reported in the Davao Gulf, only four of them can be attributed to natural causes. That means that 50 whales have died because of human industry and pollution. This is unacceptable, but how do we stop these senseless deaths?
The Next Time You Use Disposable Plastics – Think of a Dead 37-Foot Sperm Whale
So think back to your fictional day on the beach. Did you know that 18,000 tons of shampoo bottles are thrown out every year? Or that 40 billion plastic bottles end up in landfill every year. We generate around 8.8 million tons of plastic waste annually and only 15 percent of it is recycled – the majority of it makes it back into our oceans. From there it makes it into the stomachs and throats of marine life like the young sperm whale in this picture. Plastic pollution chokes, cuts, and entangles marine life and is currently endangering 700 different species with extinction around the world. So the next time you’re fantasizing about your perfect day, cut disposable plastics out of the picture, and while you’re at it – cut them out of your real life as well. Join One Green Planet’s #CrushPlastic campaign to learn about how you can stop plastic pollution at the source. Stop daydreaming about saving the world and start doing it.
Let’s #CrushPlastic! Click the graphic below for more information.
Precious marine habitat and sea life are being threatened by a planned memorial to a warrior king off the coast of Mumbai. Sign this petition to stop the building of this memorial and protect the marine environment and sea life in the Arabian Sea.
Sign our petition to the city council of Sinsheim and help us protect sharks from being subjected to a sad existence in an aquarium!
Rare Seal Has Four Gorgeous Stripes
By Christian Cotroneo
Oct. 04, 2016
It’s not every day one of the world’s most famous sea hermits pays a visit to the beach. And you might think he got all dressed up for the occasion.
When an ultra-reclusive ribboned seal was spotted on Washington’s state’s Long Beach Peninsula in August, marine scientists wasted no time in snapping a picture before the seal ambled back into the waves.
With a population of around 400,000, mostly in the North Pacific Ocean, ribbon seals aren’t especially rare — they’re designated as a species of Least Concern by the International Union for Conservation of Nature (IUCN) Red List.
That puts them squarely on the organization’s lowest rung when it comes to assessing how close an animal is to becoming extinct.
Strange then, that the last ribbon seal sighting was back in 2012, when an adult seal known only as B310 made a cameo appearance on a Seattle woman’s dock.
Unlike their cousins — harbor seals are famous for leaving their babies on shore while they forage for food — these mammals don’t bother much with dry land.
And if they do, it’s generally closer to their traditional home in the High Arctic. Ribbon seals typically frequent the frigid waters off Alaska and Russia, where it might seem their brilliant banded coats are wasted.
But aside from awing the rare human who comes across one, these bands may also help ribbon seals identify worthy mates.
The seal’s seclusive ways may have also contributed to a sense of mystery. The animals keep their secrets, often literally, close to their vest. For example, they’re the only seals who boast an internal air sac — the purpose of which still eludes scientists.
But sadly, we may start to see more ribbon seals stray from their natural climes. The animals rely on Arctic sea ice for birthing their pups. As that ice steadily disappears, so too does their natural habitat.
And too often, we’ve seen what happens when animals stray too close to where humans live.
Seals spotted on the shore are too often mistaken for being in trouble. But ultimately, the only distress they experience comes at the hands of humans thinking they’re helping.
And yes, some seals do wash up in dire need of human intervention. But in those rare cases, the best thing to do is call the experts, like the National Oceanic and Atmospheric Administration (NOAA), the agency responsible for keeping marine animals safe.
If you come across an animal who looks to be in real trouble, call the agency’s hotline at 800-853-1964.