In a season of increased shark sightings and attacks along U.S. shores on the Atlantic and Pacific oceans, there was a local flurry of interest in mid-June when scientists received a signal from a satellite transmitter they’d attached in 2009 to the dorsal fin of a motherly female great white shark they nicknamed Annika.
Surprise! The June 14 signal came from the waters between Gorda and Plaskett Creek, north of San Simeon, and documented the first time that shark has visited the beaches of Central California, according to the research team of Michael Domeier and Nicole Nasby-Lucas of the Marine Conservation Science Institute.
The pair have been studying the great white shark population off Guadalupe Island, Mexico, since 1999.
According to a June 29 report on www.sfgate.com, an 18-foot great white shark with an estimated weight of about 5,000 pounds was seen near Seacliff State Beach in Aptos, near Santa Cruz. And USA Today reported two shark attacks in two days in North Carolina.
Sign Up and Save
Get six months of free digital access to The Tribune
In case you’ve just started humming the theme song from the shark-shock film “Jaws,” the scientists would like to remind you that because a shark can swim many miles in a day (top speed estimated at about 25 mph), Annika is likely far, far away by now.
That doesn’t, however, mean there never are sharks in North Coast waters. Area surfers have reported sightings over the years.
The public can track Annika on the institute’s iTunes tracking app, called Expedition Great White, or they can log onto www.marinecsi.org/annika/.
Annika’s signal hits are happening less frequently than they were earlier in the study. Unfortunately, the battery in the nearly 6-year-old tracking device is running out of juice, Nasby-Lucas said, and for Annika’s tag to transmit, the shark must surface and her dorsal fin has to be out of the water.
Why, all of a sudden, did Annika take a sharp turn north, leaving her customary route? Where is she going? What is she doing? Has she already given birth off the Pacific coast of Baja California, where she’s had her pups before, or is she on her way there, having taken a side trip before checking into the maternity ward?
Those are among the unknowns, according to the research team. Annika’s tracking tag only alerts the scientists to some of the places she’s been, which can give them a hint of what she’s doing there.
For instance, Domier said, when the shark is heading toward Guadalupe Island, she’s probably getting ready to breed, usually between October and December. She goes to Baja to give birth after her 17- or 18-month gestation periods, and dabbles around in the Eastern and Central Pacific to eat and just be pregnant.
The shark also could be “cruising the coast, trying to get a bit of food” before she returns to Guadalupe Island to start the process all over again, Domeier said, adding that Annika’s already given birth twice during the nearly six-year tracking period. “She’s proven to be pretty consistent. …The last two times, she pupped around Vizcaíno Bay.”
Or — and Domeier’s voice perks up when he described this option, because it’s based on a possibility he’s researched for years — Annika may be taking the first steps toward becoming a “founder” of a new birthing area, a shark’s watery equivalent of a new elephant-seal rookery, for instance.
If that’s the case, “it’s possible” that the Central Coast could be home to more sharks, he said.
“I believe white shark pups have spread throughout the globe,” Domeier conjectured. “There are white sharks near both coasts of the U.S., in New Zealand and Australia. All those places have a lot of seals,” a primary white-shark meal. “But what about Chile? There are lots of seals there, too. What’s the answer? Maybe it’s because no ‘founder’ female has given birth there yet.”
Domeier said his personal belief is that “she’s given birth and is feeding …, but as a scientist, I can’t say that” for sure. He mused, “She could be recovering now from the whole birthing thing. It takes a while for the birthing organs to recover, for her to ovulate and then mate again.”
But, if Annika hasn’t yet given birth this year, Domeier is surprised she would be this far north.
“Pups seem to like the shallow, sandy water off Southern California,” he said.
There have been shark sightings before in North Coast waters, but Cubby Cashen, owner of Sea for Yourself Kayak Tours in San Simeon, said Tuesday he doesn’t expect to see Annika and doesn’t expect her recent swim-by to affect his business.
“I haven’t seen a white shark in the cove in my 12 years here, and I’m always looking for animals,” on tour or from the shore, he said. “I just assume they’re there all the time.”
Does that concern him? He concluded, “I worry more about driving home on Highway 1.”