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Seafood's new normal: An ecosystem at risk

Tara Duggan, SAN FRANCISCO CHRONICLE
In the shallow waters off Elk, in Mendocino County, a crew from the California Department of Fish and Wildlife dived recently to survey the area’s urchin and abalone populations. Instead of slipping beneath a canopy of leafy bull kelp, which normally darkens the ocean floor like a forest, they found a barren landscape like something out of “The Lorax.”
A single large abalone scaled a bare kelp stalk, hunting a scrap to eat, while urchins clustered atop stark gray stone that is normally striped in colorful seaweed.
“When the urchins are starving and are desperate, they will leave the reef as bare rock,” said Cynthia Catton, an environmental scientist with Fish and Wildlife. Warm seawater has prevented the growth of kelp, the invertebrates’ main food source, so the urchins aren’t developing normally; the spiky shells of many are nearly empty. As a result, North Coast sea urchin divers have brought in only one-tenth of their normal haul this year.
The plight of urchins, abalones and the kelp forest is just one example of an extensive ongoing disruption of California’s coastal ecosystem — and the fisheries that depend on it — after several years of unusually warm ocean conditions and drought. Earlier this month, The Chronicle reported that scientists have discovered evidence in San Francisco Bay and its estuary of what is being called the planet’s sixth mass extinction, affecting species including chinook salmon and delta smelt.
Baby salmon are dying by the millions in drought-warmed rivers while en route to the ocean. Young oysters are being deformed or killed by ocean acidification. The Pacific sardine population has crashed, and both sardines and squid are migrating to unusual new places. And Dungeness crab was devastated last year by an unprecedented toxic algal bloom that delayed the opening of its season for four months.
Read more at: Seafood’s new normal: An ecosystem at risk

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North Coast kelp beds ‘like a desert’ this year

Mary Callahan, THE PRESS DEMOCRAT

Abalone diver Richard Hayman already had been observing troubling shifts in underwater conditions off the North Coast when he found himself gazing around the ocean floor in Arena Cove with a new level of alarm.

“It’s like a desert out there,” he recalled, describing a barren underwater landscape stripped of vegetation by colonies of purple urchins that vastly outnumbered the mollusks he sought. It looked, he said, “like a fire went through.”

During 25 years of diving, Hayman had come to know the area offshore the Mendocino County town of Point Arena as a source of succulent abalones, abundant and plump with meat.

 In June, he came ashore with his limit of three, despite a substantial reduction in the number of shellfish he saw. But they were so withered that, once removed from their shells, the creatures weighed less than a third of what they normally would.

“They’re starving to death,” the Calistoga man said. “It’s obvious.”

Hayman, 52, was among a dozen veteran divers who recently shared their observations at the midway point to the 2016 red abalone season, which resumes Aug. 1 after a month-long break and runs through November.

What they revealed was near consensus that all is not as usual out there, off the edge of the land, beneath the waves.

Scientists had predicted as much just before the season’s April 1 start, describing an unprecedented collapse of the North Coast’s iconic bull kelp forest and the resulting gloomy outlook for the abalone fishery and the overall ecosystem.

Divers reporting in over the past few weeks — people like Napa diver Andy Treweek, 55 — witnessed as much in some areas, where they discovered a few undersized abalone living on near-barren ocean floor.

Read more at: North Coast kelp beds ‘like a desert’ this year

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Collapse of kelp forest imperils North Coast ocean ecosystem

Mary Callahan, THE PRESS DEMOCRAT

How to help: State scientists are seeking help with data collection and other activities, as well as observational accounts, photos and videos related to the urchin barren. Shared images and information should, if possible, include the date, location and depth at which they were acquired. Contact Cynthia Catton at Cynthia.Catton@wildlife.ca.gov or 875-2072.

Large tracts of kelp forest that once blanketed the sea off the North Coast have vanished over the past two years, a startling transformation that scientists say stems from rapid ecological change and has potentially far-reaching impacts, including on several valuable fisheries.
The unprecedented collapse has been observed along hundreds of miles of coastline from San Francisco to Oregon. The region’s once-lush stands of bull kelp, a large brown alga that provides food and habitat for a host of wildlife species, have been devoured by small, voracious purple urchins. In the most-affected areas, denuded kelp stalks are almost all that remains of plant life.
Scientists have described the landscape left behind as an “urchin barren.” Other factors, including warmer water, also are to blame, they say.
“It’s no longer a kelp forest,” said Cynthia Catton, an environmental scientist with the California Department of Fish and Wildlife, stationed in Bodega Bay.Laura Rogers-Bennett, another Bodega Bay scientist, said it is as if whole terrestrial forests were disappearing, only in this case they are underwater and out of sight.
“A lot fewer people swim through the kelp forest,” she said. “But if they do right now, they‘re going to really see that there are huge changes that have taken place in the last year and a half or so.
”The discovery has taken shape as California scientists and policy makers are raising a broader alarm over the ebbing health of ocean waters, pointing to their increasing warmth, acidity and other conditions that have affected wildlife and the fishing industry.
Read more at: Collapse of kelp forest imperils North Coast ocean ecosystem | The Press Democrat