CORVALLIS, Ore. - Seals, sea lions and other "pinnipeds" are vital cogs in many marine ecosystems, yet they face an uncertain future and threats from fisheries, climate change and marine debris - as well as from other top predators.
While their populations are healthy and near carrying capacity in the Pacific Northwest, populations of seals and sea lions have declined to historically low levels in western Alaska and the Bering Sea.
Markus Horning, a pinniped expert from Oregon State University's Marine Mammal Institute, will discuss the reasons for these differences this Monday, May 10, in a Science Pub presentation at the Old World Deli, 341 S.W. 2nd St. in Corvallis. His talk, "Consummate and Consumed Predators: Threats to Seals and Sea Lions in a Changing Ocean," begins at 6 p.m.
Science Pub Corvallis is free and open to the public; attendees are encouraged to arrive early, as space and seating are limited.
Pinnipeds are effective marine predators and their consumption of salmon has raised the ire of some Northwest fishing enthusiasts - even though salmon and seals have co-existed for thousands of years. Yet their protected status has also created challenges for resource managers, who must balance the recovery of multiple threatened species.
In his talk, Horning will discuss the roles and impact of research, rescue and rehabilitation programs on these "charismatic, yet difficult to monitor" marine mammals. He also will touch on recent high-profile rescues of sea lions in Florence and Newport that were threatened by entanglement with marine debris.
And he will discuss how climate change, killer whales and other factors affect marine mammals.
One reason for the decline of Steller sea lions in Alaska may be predation. Horning is principal investigator in an ongoing study that uses lifelong monitors implanted inside the sea lions to track the animals' temperature rates - and provide clues to the cause of their eventual deaths. Preliminary results suggest greater-than-expected predation of these protected marine mammals by orcas.
In another study, Horning is learning more about the extraordinary physical capabilities of Weddell seals in Antarctica. When these seals dive, he says, they have the ability to reduce the flow of blood to many of their organs, including their skin, liver and kidneys, while keeping their hearts, brains and swimming muscles supplied with blood and oxygen. That allows them to reduce their heart rate from about 100 beats per minute to 40 beats - and sometimes as low as five beats per minute - and remain underwater in search of prey.
Horning's research is funded by NOAA and the National Science Foundation. He is one of the leading scientists affiliated with OSU's internationally recognized Marine Mammal Institute, which is headquartered at the university's Hatfield Marine Science Center in Newport.
For more information on the lecture series, call 541-737-4611 or visit Corvallis Science Pub on Facebook.
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Markus Horning, 541-867-0270