Could use of drones be part of the sea lion deterrent picture?
Although San Diego city officials will not employ the services of the sea lion behaviorist recommended by the group suing over the stench at La Jolla Cove (from bird and sea lion waste), the city will instead hire another marine mammal expert to assess the sea lion colony at the Cove.
According to spokesperson Bill Harris, the city is set to sign a contract for $24,900 with Doyle Hanan & Associates to “study and identify potential opportunities for changing the behavior or haul-out conditions of the sea lion colony now expanding along the La Jolla coastline,” and file a report with the city. “Our desire is for them to get as much information to us as possible by the end of June so we can make decisions about (the need for) a more complete study in the fiscal year ahead,” he said.
Doyle Hanan was previously employed by the city to survey the harbor seal population at Children’s Pool/Casa Beach.
Harris said the work would help the city determine what steps are necessary for development of a coastal management plan that “focuses on conditions and opportunities in the management of the coastline and its wildlife within the city.”
(Last year, City Council President Sherri Lightner unsuccessfully sought $200,000 in city funding for her vision of such a coastal management plan to address the proliferation of marine mammals and seabirds along La Jolla’s coastline.)
Harris said the city will continue its application of “Blue Eagle” microbial foam to the bluffs above La Jolla Cove (which digests bird guano), in an effort to further reduce odors. Although the city is still assessing how frequently the bluffs need to be treated, Harris said it would likely step up treatments to twice a month, for the next five months (at $2,000 per application).
Harris said a gate leading to the Cove bluffs will remain open and accessible to the public — an access point granted in December 2013 at the request of community members who view human presence on the bluffs as a deterrent to sea lions congregating there.
• Pinniped expert secured
Doyle Hanan obtained his doctorate degree studying harbor seals. “I’ve spent a lot of time tagging, following … and swabbing seals and sea lions for the last 25 or 30 years,” said Hanan, a retired senior marine biologist supervisor with the California Department of Fish and Wildlife.
Hanan’s company provides sea lion deterrent methods approved under a provision of the Marine Mammal Protection Act, which includes use of such things as noise, water jets or low-level electric current, blocking their access with fences, or other means.
Before he can determine what might work, Hanan said he must gather baseline information about the colony — something that has been done for the seals at Children’s Pool (which he assisted), but not for the sea lions at La Jolla Cove.
“That’s what’s needed before you can determine what might work or might not work … (and) make science-based decisions,” said Hanan last week, speaking with La Jolla Light by phone from Seattle, where he was attending a marine mammal deterrent conference organized by NOAA Fisheries (aka National Marine Fisheries Service). The conference featured nine pinniped experts and other marine mammal scientists speaking about everything from ways to keep dolphins away from oil spills, to preventing whales from entering heavy fishing areas where they might ingest hooks, or have a fatal collision with the bow of a silently approaching ship.
“A lot of times whales don’t even hear them coming,” Hanan said. “It’s a huge topic that people have been working on for the last 10 or 15 years.”
Hanan said the conference focused on non-lethal deterrent methods that fit into a category or description of the Marine Mammal Protection Act’s Incidental Harassment Authorization provision.
One method of pestering sea lions proposed and discussed during the conference was the use of drones.
“Anything new or novel will alert them,” said Hanan, who witnessed people flying drones recreationally at Children’s Pool last summer, which he said definitely disturbed the seals.
“When they flew over the seals, they would sometimes flush,” or scurry back into the water. Conversely, he said seals are used to fixed-wing aircraft flying over Children’s Pool, and are largely undisturbed by them.
Hanan said drones are just one possible deterrent method scientists and marine mammal experts are studying. “Drones need research,” he stressed.
• SEE RELATED STORY — Lifeguards: Don’t call 911 for sea lion rescues for La Jolla Cove — lajollalight.com/news/2015/feb/17/lifeguards-say-dont-call-911-for-sea-lion-rescues