Fur traders in the 18th and 19th centuries hunted the animals to the brink of extinction, allowing sea urchin numbers to skyrocket, Dr. Rasher said. “Will it result in negative impacts to other species? The key might be moving them into San Francisco Bay — away from great white sharks, Marin animal care centers report distemper outbreak, Marin Voice: Crab fisherman concerned ‘ropeless’ gear not best answer, | Natural resources and environment reporter, Heating failures vex Marin City public housing residents, Point Reyes National Seashore gets new superintendent, Big Basin redwoods: Drone video shows extent of wildfire over famed state park, Marin officials weigh grant requests by nonprofits. Sea otters eat 25% of their body weight a day. The otters, whose population has stalled in recent years at around 3,000, are stuck. In 1986, river otters were listed as an endangered species in Nebraska. Now, even the living, red-algae reefs on which the swirling stands of kelp once stood are in peril. It’s a place they haven’t inhabited for nearly 200 years, but some fishermen might not be ready to welcome them back. But the potential is definitely there.”. Paul Rogers has covered a wide range of issues for The Mercury News since 1989, including water, oceans, energy, logging, parks, endangered species, toxics and climate change. “The question that should be addressed before we buy into this is what impact will it have?” Conroy said. The research analyzed hazards — including large commercial ships, high-speed ferries, oil spills, fishing gear and toxins such as mercury. In just a few decades, this bustling civilization has withered into a ghost town. The concept is still in the early stages. “There was this incredible diversity,” he said. Many lived in San Francisco Bay, but by the Gold Rush, they were all but gone. “Given those two things happening simultaneously, it’s really getting hit from both sides,” said Alyssa Griffin, an ocean biogeochemist at the University of California, Davis, who wasn’t involved in the study. The aquarium has proven that otters don’t need rocky shorelines and kelp forests to thrive. Sea otters were hunted to near extinction during the maritime fur trade of the 1700s and 1800s. While he is hopeful that further research into reintroducing otters to the bay will show promising results, Boehm said more research and input from all stakeholders who use the bay is needed before a decision should be made. They found food. The otters, whose population has stalled in recent years at around 3,000, are stuck. “San Francisco Bay is a busy place with a lot of things going on,” said Rudebusch, lead author of the study. Where algae had once coated the Aleutian sea floor like a swath of pink pavement, only patches remained. Setting up a similar program in San Francisco Bay could be five to 10 years away before all the studies and permits are completed. Shark bites are a frequent cause of injury for the otters they care for, he said, but there are also cases of malnutrition and parasitic infections. Fur traders in the 18th and 19th centuries hunted the animals to the brink of extinction, allowing sea urchin numbers to skyrocket, Dr. Rasher said. Lutra nippon (Japanese otter) — possibly extinct, according to IUCN, and may not have been a separate species Lutra sumatrana (hairy-nosed otter) Lutrogale perspicillata (smooth-coated otter) The thinking: What if several dozen otters were moved under the Golden Gate Bridge into the bay? Watch: Tipsy squirrel wins the internet Could they flourish, reproduce and spread to a new part of the state? When the oceans had been healthy, the team found, nips from urchins had barely scuffed the algae’s surface. Dungeness crab was a $51.8 million fishery last year, said Mike Conroy, executive director of the Pacific Coast Federation of Fishermen’s Associations in San Francisco. In just a few decades, this bustling civilization has withered into a ghost town. When urchin populations spiked in response, the reefs held their ground. San Francisco Bay might be savior for sea otters, Click to share on Twitter (Opens in new window), Click to share on Facebook (Opens in new window), Click to email this to a friend (Opens in new window), Want to save sea otters? Aleutian sea otters have been in flux before. “You can travel down 10 miles of coastline and never see an animal,” he said. Since the 1990s, the Aleutian sea otter has been "functionally extinct," researchers said. Protected by the Endangered Species Act in … From 2002 to 2016, the aquarium released 37 otters there. “It would essentially end up lifting the sea otter out of its endangered species status,” said Brent Hughes, assistant professor of biology at Sonoma State University and lead researcher in that study. “The reefs are producing less dense skeletons,” Dr. Rasher said. When the researchers grew urchins and algae under conditions that simulated the preindustrial past, the present and a projected future in the lab, they found that contemporary circumstances spurred urchins to gnaw away at algae up to 60 percent faster. “Just seeing that trend is staggering,” Ms. Boyd said. The aquarium has released dozens back into the wild, most notably at Elkhorn Slough, an estuary near Moss Landing full of tidal marshes, creeks and muddy channels — similar to San Francisco Bay. But the 1-million-acre bay has enough food — crabs, clams, mussels and worms — to support up to 6,600 otters, a major study last December found. They can’t expand their coastal range any farther north than Pigeon Point in San Mateo County because the area is thick with great white sharks. “For their size and how cute they are, they are aggressive eaters.”. Now, Dr. Estes said, more than 90 percent of those otters are gone. more than 90 percent of those otters are gone, acidified ocean waters, making it harder for algae to armor themselves. “It was spectacularly beautiful.”, When the Otters Vanished, Everything Else Started to Crumble. Since it can be demonstrated that the droppings were in fact those of an otter, the droppings found in 1999 indicate the presence of at least one individual well past the last known sighting. Changes yet to come will likely prompt the grazers to pick up the pace even more, the team’s analysis showed, barring sweeping change in carbon emissions. Sea otters, which can eat nearly 1,000 sea urchins a day, have seen their numbers along Alaska’s Aleutian Islands shrink by 90 percent in recent decades. “Predator loss can impact the environment in ways we haven’t even thought of,” Dr. Griffin said. Aleutian sea otters have been in flux before. When the number of crabs drops, the sea slugs expand in number, and they eat more algae, allowing the sea grass — where young fish hide — to flourish. That could make it hard to sustain larger otter populations: Once introduced, they might just disappear all over again. But they were hunted relentlessly in the late 1700s and early 1800s by Russian, British and American fur traders for their pelts, which are denser and softer than mink fur. “And temperature exacerbates that issue.”. A new study published this month found that some parts of the bay would be safer for otters than others — in particular, in waters near Marin County. Post was not sent - check your email addresses! The smooth-coated otter is listed as "vulnerable" (has a high risk of extinction), and the Eurasian and Asian small-clawed otters as "near threatened" (has a potential future risk of extinction). A single sea otter can scarf down nearly 1,000 sea urchins a day. In 1970, Jim Estes made his first trek up to Alaska’s Aleutian Islands. Of those, 31 stayed in the slough. Big cities, ports and heavily trafficked areas, such as the Golden Gate and Bay bridges, and the Oakland waterfront, pose the highest risk. Fish and Wildlife Service, and probably several state permits. “In order for the population to increase they need to expand into more territory,” said Jane Rudebusch, a marine researcher with San Francisco State University. Against the backdrop of climate change, the delicate underwater ecology of Alaska’s Aleutian Islands is hurting from declines in otters. Back then, crowds of these charismatic creatures shrouded the sprawling archipelago, congregating in “rafts and bunches, as many as 500 at once,” said Dr. Estes, an ecologist at the University of California, Santa Cruz. The Marine Mammal Center in the Marin Headlands partners with the aquarium in responding to reports of injured or malnourished otters and pups. The center responds to dozens of otter reports each year, and typically cares for young adults, according to the center’s chief executive officer Jeff Boehm. Warmer temperatures also speed animal metabolism, driving urchins to eat even more enthusiastically than usual. “There are a lot of stakeholders and understanding the needs and concerns of all of those alongside the data and the concerns and the modeling of the scientists is going to be a really rich discussion.”. Dr. Estes, who is 74, hasn’t visited the Aleutians since 2015. Using “surrogate mother” otters that live at the aquarium, the orphans learn how to feed, groom and socialize.