Two hi-tech buoys designed to eavesdrop on whale conversations have vanished from their moorings off Point Cabrillo and Point Reyes. The recorders were installed last year in an effort to count killer whales traveling through Northern California.
Whether endangered southern resident killer whales habitat includes Mendocino County could have an impact on local ocean development plans, including wave energy, oil drilling or Navy testing. There are less than 100 of the southern resident species in existence and much about their lives remains a mystery.
The recorders turned out to be even more elusive than the killer whales.
The National Oceanic and Atmospheric Administration (NOAA) made a fruitless search last month for the two missing recorders before giving up. Then, updated models were installed in the exact same locations.
NOAA scientist Bradley Hanson says all three of a then-new buoy model were lost at sea. The third device, installed in the outflow of the Columbia River in Oregon came back to NOAA after being caught in the net of a fisherman. That one has yielded important information about whales, Hanson said.
NOAA started using such devices in 2005 off Washington State.
“They were the first recorders we lost since we started this work in 2005,” he said.
Hanson said an investigation found a flaw in the design of a new model. Either the anchor was too light or the buoy had too much flotation. This apparently allowed the devices to drift to an unknown new location, said Hanson.
Similar devices have been deployed to study whales in Alaska since 1999. Online scientific studies show the recorders have gathered important information about blue whales, gray whales, killer whales and right whales.
“The information we get tends to change many of our preconceived notions,” he said.
Whales often appear in places they are “not supposed” to be when the recorders are recovered.
“In the recorder recovered from the Columbia there is a sound that we have not been able to figure out what it is,” he said.
The $4,000 recorders contain a sophisticated listening device and a computer hard drive. Each recorder is 30 inches long and 4 inches in diameter. They are deployed attached to a floating device that reaches only halfway up from the ocean bottom. The batteries last about six months, saving energy by turning on every seven minutes for 30 seconds. That timing allows the device to hear every whale that swims within three miles.
The recorder installed about three miles off Point Cabrillo was about 200 feet down in 400 feet of water. NOAA had saved money on a model that wasn”t interactive like the older ones. It was designed to release the buoy when a signal was activated, allowing the anchor cable to drop to the bottom alongside the anchor. But when the recovery crew went to the location (N 39.20892 W 123.53601) and sent the release signal, nothing happened.
Hanson said consulting with local fishermen caused NOAA to move placement of the device to avoid nets and lines.
Could the missing device now prove hazardous to fishing?
“There is the potential that this could cause gear damage, although in the case of the one that was trawled up neither it nor the trawl gear were damaged,” Hanson said.
There are new devices available, such as a drone explorer and an ocean “glider,” which use changing pressure differentials for energy and propulsion. Cost has prohibited NOAA from using some of the newer devices. NOAA announced this week it has received $830 million from President Obama”s stimulus package.
Hanson is still hopeful the missing devices could turn up, perhaps even on a local beach. The recorders have contact information on them. Hanson”s office number is 206-860-3220.
