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Otter-ly Beneficial

Sea otters are an aquatic member of the weasel family found along the coasts of the Pacific Ocean in North America and Asia. They have webbed feet, water-repellent fur to keep them dry and warm, and nostrils and ears that close in the water.

California’s southern sea otter has been listed as a threatened species under the Endangered Species Act since 1977.  There are only about 3000 let in the wild. They face many challenges. I remember images of sea otters covered in oil with the Valdez oil spill  in 1989; nearly 1000 sea otters deaths were attributed to this incident. 

Sea otters float in forests of kelp, wrapping themselves in the giant seaweed for anchorage and support.

They are considered a keystone and sentinel species because they help stabilize the nearshore environment. Sea otters eat sea urchins and other invertebrates that graze on giant kelp.  Kelp forests are important to maintain because other animals depend on kelp for habitat and kelp forests protect coastlines from storm surge and absorb carbon dioxide which otherwise would contribute to global warming.

Sea Otters in the Pacific Ocean dig clams out of fields of eelgrass leaving divots in the dense mats. A study published in Science, Oct. 2021,concluded that in areas inhabited by sea otter, the eelgrass is more genetically diverse and resilient, physical disturbance by recovering sea otter populations increases eelgrass genetic diversity.  The act of otters foraging disturbs the seabed; specifically the digging provides more space and sunlight for seeds to settle and germinate. Eelgrass is imperiled as a result of climate warming and pollution.  The plants are vital to ecosystems because they filter contaminants from the water, store carbon, and provide habitat and food for many animals, including otter. This in an example of how predators influence ecosystems and how various components are interdependent.

Sea otters were nearly hunted to extinction until they gained protection with the signing of the International Fur Seal Treaty of 1911 and they acquired more protection with the Marine Mammal Protection Act of 9172 and the Endangered Species Act. In 2006, Defenders of Wildlife helped California establish the California Sea Otter Fund, where citizens could contribute to research, education, and law enforcement to benefit sea otters on their state tax form.  Defenders of Wildlife has other activie initiatives to protect sea otters.

Sea otters aren’t recovering or stabilizing because they are succumbing to fatal white shark bites.  Other problematic factors contributing to their mortality is infections diseases, pathogens and parasites, food availability, nutritional deficiencies, habitat degradations, coastal pollutants- oil spills are a serious threat as is contaminant exposure.

These prints are part of a series entitled Conservation of California Coastal Critters.

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