White shark attacks on sea otters along the central coast of California hit record numbers for the month of August, this year, according to a 760KFBM.com report. The average number of shark attacks on sea otters for the month of August over a ten-year period is seven. In August of this year, scientists recovered 19 otters with apparent shark bite wounds.
Typically, when a white shark attack does occur on a sea otter, the shark will bite and then release the sea otter upon realizing that it a preferred prey item, according to Mike Harris of the California Department of Fish and Game. Harris goes on to note that unfortunately most of these attacks still prove fatal. Due to the nature of the severity of the bites and the anatomy of the sea otters, even an exploratory bite or a bite of “mistaken identity” can result in injuries that the sea otters cannot recover from.
The 760KFMB article notes that some researchers are speculating that unusually mild summer temperatures in the area might explain the increase in the incidences involving white sharks attacking sea otters, as the cooler ocean temperatures make area waters preferable to white sharks.
In addition to the shark attacks on sea otters, a New York Times article is reporting that a University of California, Santa Cruz report has linked sea otter deaths in California to a freshwater toxin. The toxin microcystin is produced by blue-green algae, and the report suggests that the toxin has leaked into the Pacific. Researchers involved in the study say that least 21 sea otter deaths were linked to the toxin.
Both sea otters and white sharks are listed as threatened species on the IUCN red list. Sea otters are classified as “endangered,” while great white sharks are currently classified as “vulnerable.”