Friday, October 31, 2014

Sharks and seals

From the Cambrian:

Elephant seals are top predators, but they are also prey for sharks and killer whales.

Occasionally, a wounded seal lands on the beach, or a healed scar gives silent witness to an attack.
This wounded seal rested at Piedras Blancas during the first week of October. Shark researchers have found that sharks have seasonal migrations and spend the time between August or September through March feeding in their favorite places along the California coastline. Those places — Tomales Bay, the Farallon Islands, Año Nuevo — are where they find plenty of marine mammals, like juvenile elephant seals, to eat.

This severely shark-bitten seal made it back into the water.  Maybe she'll survive.
To find out whether sharks are feeding at Piedras Blancas, scientists from Hopkins Marine Station put a buoy offshore at Piedras Blancas in 2013, equipped with underwater receivers to track tagged sharks. Scientists tag sharks with acoustic tags that can be detected if the shark swims within 500 meters of the underwater receiver. Over several months, only two of the tagged sharks swam past, although it was exciting enough to know that Duke, a 17-foot male, was swimming out there.

The Piedras Blancas buoy isn’t there anymore but may be replaced in the future. The SharkNet app, available free for iOS systems, lets anyone follow the tagged sharks on their travels.

Researcher Taylor Chapple came to Cambria in August to explain how he tags sharks to Friends of the Elephant Seal docents. Sharks are visual hunters, so he and his team attract them with a wooden dummy shaped like a seal, covered in indoor-outdoor carpet. They add some marine mammal blubber to entice the sharks close enough for the 10 to 20 seconds needed to shoot a digital tag into the dorsal fin. The unique scars on each dorsal fin also identify the sharks as individuals. Chapple has evidence that about 219 adult and sub-adult sharks live along California’s Central Coast. He and his team have tagged about 130 of them.

The dummies sure get chewed up.

Keep your eyes out for the tags on the beach. They automatically pop off after a preset period of time and float away. They continue to broadcast a signal so researchers can pick them up, but in a vast ocean, that isn’t always possible. They contain far more data than they can upload to satellites, so it’s important for the shark research project to retrieve them when possible. Researchers offer a reward of $200 to $500 for turning one in.

“We’re throwing thousands of dollars over the side every time we tag a shark,” Chapple said.
When the juvenile elephant seals return to the beaches for their fall haul-out, sharks follow. In the Farallons and at Año Nuevo, sharks gorge on the juveniles. Juveniles make a bigger meal than the small pups but aren’t as fierce and dangerous as adult seals.

“Hunting a pup is a lot of effort for a small benefit,” said Chapple, who said the researchers call them “pupsicles.”

Sharks attack from below, accelerating to hit their prey with force and disable it with a single bite. They attack from behind. A seal bitten in the tail can turn and fight back.

A serious physical injury can interfere with the shark’s ability to hunt.

“Seals are dangerous for sharks,” he said. “If a shark loses an eye, it’s a serious consequence.”

Read more here: http://www.sanluisobispo.com/2014/10/22/3309187/elephant-seals-sharks-piedras.html#storylink=cpy

Saturday, October 18, 2014

Saving condors from extinction

Something was wrong with Condor 444.
Melissa Clark was working from home in Pacific Grove Aug. 15, watching Big Sur condors tear into carrion via two live webcams. But 444 – nicknamed Ventana, and kind of famous as the first wild-hatched chick in the flock – wasn’t her usual feisty, dominant self.

“She was acting lethargic and clumsy, having a hard time getting up onto perches,” says Clark, a field biologist for Ventana Wildlife Society.
Clark called her boss, VWS Senior Wildlife Biologist Joe Burnett. He told her to go capture Ventana, fast.
When Clark and David Moen, the other VWS field biologist, arrived at VWS’s remote Big Sur sanctuary, Ventana flew into a tree just out of their reach. Clark and Moen slept in VWS’s cabin, then set out the next morning with a radio receiver cued to Ventana’s signal.
The condor left her roost and flew into a gully. “She tried to hide under a bush because she couldn’t fly, and I was able to grab her without a net,” Clark says. “She was very pale and very weak.”
Ventana, like scores of free-flying condors before her, was gravely ill with lead poisoning.
Clark walked a quarter-mile to the nonprofit’s SUV, one arm hugging Ventana close and the other hand holding the bird’s head still. She loaded the emaciated scavenger into a kennel and drove her to Los Angeles Zoo.
VWS staff say the endangered species doesn’t have a chance in the wild unless the lead poisoning stops ASAP. The nonprofit is taking a two-pronged approach: nudging wild condors toward the coast to feed on cleaner carrion, and replacing toxic lead bullets with copper.
For that, they need the hearts and minds of hunters.
~ : ~
Condors have enemies. That’s why Burnett and VWS Executive Director Kelly Sorenson ask that I don’t name the Big Sur state park we’re hiking through to get to a local nest. We veer off-trail and clamber up a rock wall, where Burnett sets up a telescope and Sorenson pulls out his binoculars. They peer across the canyon to where condor poop has whitewashed the granite.
We’re spying on one of three condor chicks that hatched in Big Sur this year. Another was born in a redwood to the south, a third in the Indians region of Los Padres National Forest.
VWS tracks the free-flying condors of Big Sur like ninja paparazzi. Every bird in the flock has been repeatedly probed by veterinarians, its blood drawn, its feathers measured. One-quarter of them wear GPS tags, the rest radio transmitters. They all carry tags with numbers large enough to see from the ground as they soar overhead. The chicks’ nests are bugged with motion-activated cameras, and at VWS’s Big Sur sanctuary (another undisclosed location), biologists drop stillborn calves from Big Sur dairies for lead-free condor snacking under the watchful lens of a remote-controlled webcam.

Plight of the Condors
It’s not that the birds couldn’t find carrion on their own. It’s just that some of those dead things, especially varmints like ground squirrels and coyotes, have been killed by lead bullets, which shatter through the wound channel.
Even a fingernail-sized fleck of lead can be enough to paralyze a condor’s digestive tract. “Lead is evil. It kills them really slow,” Burnett says. “They’re hungry, but they can’t push food through.” What follows: severe dehydration, malnutrition and neurological shutdown.
Sorenson says condors could survive on their own without the threat of lead. “This bird is very intelligent, very long-lived and tough as nails,” he says. “I’d hate for people to think of them as a conservation-dependent species, because it’s our own doing.”
Condor range had once covered much of the West Coast, but the scavengers lost their main food sources when the fur trade decimated whale, sea lion, seal and otter populations. By the early 1900s, only one condor nest remained on the Central Coast, near Pinnacles. By the mid-1960s, condor numbers had dropped to less than 60 statewide. The feds listed them as endangered in 1967. Twenty years later, the U.S. Fish and Wildlife Service captured the last free-flying condor in southern California. Only 27 of the species remained, all of them captive at the San Diego and Los Angeles zoos.
In 1997, VWS released one of those captive condors in Big Sur. Pinnacles joined the effort with its own release in 2003. Four years later, the first Central Coast mating pair successfully hatched an egg in the wild. That chick was Condor 444, Ventana. There are now 36 condors in Big Sur, plus 26 at Pinnacles, bringing the Central Coast flock to 62.
At Burnett’s last count, there were 434 condors in the U.S., 232 of them free-flying and 202 captive. VWS and Pinnacles National Park staff co-manage the Central Coast flock. The other three wild flocks are in Southern California, Arizona and Baja California, each with their own managing entities. The feds count on this support from nonprofits: VWS raises about 95 percent of its $300,000 annual condor program budget from private sources.
One of the conditions needed to downgrade condors’ conservation status from endangered to threatened: two separate groups of 150 free-flying birds, with 15 breeding pairs each. The two California flocks now total about 130, with 14 breeding pairs – close to their target.
But another key condition is positive natural growth, and that’s not happening. The free-flying population is only growing because of releases from captivity and intense management, Sorenson says: “They’re being held back by lead.”
~ : ~
Spent ammo isn’t the only poison lacing wild condor food. The other big one is DDT, of Silent Spring notoriety. Even after the U.S. Environmental Protection Agency banned it in 1971, the pesticide, once dumped into the ocean off Southern California, persisted in the food web with a half-life of about 40 years.
The eggshells of Central Coast condors, which eat dead marine mammals, are still about 34-percent thinner than those of Southern California condors, which don’t, Burnett says.
Somehow he’s cheerful about this. Levels of the DDT metabolite, DDE, are decreasing over time, he says, and most condor eggs seem able to handle a certain amount of thinning. When they seem too fragile to make it in the wild, VWS launches a dramatic, covert rescue op.
As detailed in a 2007 Weekly cover story, VWS staff snatch DDT-thinned eggs from wild nests and take them to special incubators at the L.A. Zoo. Then they replace them with strong-shelled eggs laid by healthy captive condors. The wild parents incubate and raise the captive-laid chick, apparently unaware of the switch, while a special veterinary team tends to the wild-laid egg in captivity. VWS and its partners at L.A. Zoo have pulled egg swaps off eight times so far, most recently last year. Ventana was one of the first adoptees in that program.
But the 16-week-old chick I visited, Nestling 753, hatched without VWS’s help. Burnett sees his strong eggshell as evidence of decreasing DDT levels.
It’s one of several threats he and Sorenson say are now under control. Power lines have killed five condors in Big Sur, but VWS worked with Pacific Gas & Electric to replace the high-risk lines with special insulated tree wires. Litter is another issue: The scavengers can mistake a broken piece of PVC for a bone fragment. Only one local condor has died from ingesting plastic, Sorenson says, and VWS is participating in highway cleanups to lower that risk.
Burnett pauses to lean into his telescope, baseball cap shielding his eyes, and watch the hunched, unmoving chick in the hushed redwood canyon.
“We’re on condor time now.”
~ : ~
Melissa Clark, the VWS condor technician, is part of a team doing monthly health checks on two Big Sur condor chicks. She waits on the ground while Burnett, a veterinarian and an L.A. Zoo condor handler take turns rock-climbing to the nest.
Once up there, the handler gently grabs and blindfolds the chick to keep it calm. The VWS team measures its growth, palpates its stomach for microtrash and draws some blood. If that blood tests high for lead, they put the chick in a crate and drive it straight to L.A. or Oakland Zoo for treatment.
The veterinarian teams, which specialize in lead-poisoned condors, save some of them. Others, they can’t.
At the VWS Discovery Center in Andrew Molera State Park, Sorenson shows me a text Burnett sent him Aug. 20. It’s a photo of Ventana at the L.A. Zoo, crouching on white blankets in a plastic enclosure. It reads:
“444 barely hanging on, they are going to do an emergency blood transfusion as last ditch effort… :(”
Sorenson cringes. “Gah, I hate to get these,” he says. “What else can we do? We’re giving away bullets.”
~ : ~
He’s not kidding. For the past three summersVWS has gifted about 2,000 of boxes of copper ammunition to hunters in Monterey and San Benito counties. It’s a bizarre dynamic: Environmentalists who donate to VWS helped buy $65,000 worth of bullets.

Plight of the Condors
That ammo giveaway was the turning point for Kevin Kreyenhagen, a lifelong hunter and rancher who lives in Carmel Valley. “They’re investing their own money to help hunters with the transition from lead to non-lead,” he says. “I don’t see any other group that’s ponied up money for free ammo.”
Kreyenhagen ticks off a dozen reasons why hunters might resist the switch to non-lead bullets. It’s being forced on them, for one thing: A 2008 state law requires non-lead ammo in condor range, including Monterey County. “It’s kind of deflated me,” he says. “I’ve loaded up with so much lead ammunition. Now what do I do with it?”
Some rifles don’t shoot well with non-lead, he says. That has to do with bullet weight: “All of a sudden the performance just falls off the table.” He says copper works OK for the deer and wild boar he hunts with centerfire bullets in Monterey and Fresno counties, but rimfire – for pests on his family’s 10,000-acre cow/calf operation outside Coalinga – is different.
An infestation of ground squirrels can mess up water lines and make holes that trip cattle, Kreyenhagen says. He won’t use rodent bait because it poisons other wildlife, so he kills squirrels with a .22-caliber long rifle. Non-lead bullets don’t hold their point of aim as well as lead, he says.
2013 state bill, AB 711, expands the lead-bullet ban to all hunting in California in 2019. The six-year delay is meant to let ammo manufacturers ramp up production of alternatives, but one group says that’s still not enough time.
Last month, the National Shooting Sports Foundation released a report concluding AB 711 could seriously suppress California hunting. The report finds gaps between supply and projected demand for a number of gauges, particularly rimfire – bullets that kill the varmints condors love to eat. For those targets, the non-lead option is almost always copper.
Ammo manufacturers introduced copper bullets in the 1980s as a higher-performing alternative to lead, Sorenson says, but they’re still considered a niche market. “Once you start talking about that being the norm,” he says, “then everybody starts freaking out.”
He gets it: A lead-bullet ban won’t work without an accompanying surge in alternative ammo supply. “Even if 100 percent of [hunters] wanted to switch to copper – and that’s not the case – there’s no way they could,” Sorenson says.

Plight of the Condors
California has about 281,000 licensed hunters, or 1 percent of the state’s adults, as of July 2013, according to California Department of Fish and Wildlife. Ammo manufacturers, reportedly struggling to keep up with a demand for traditional lead bullets, might not retool their operations just for California’s new mandate.
Free boxes of copper bullets are both VWS’s attempt to stimulate demand and an olive branch to hunters. The message: “We’re not trying to take away your guns,” Sorenson says. “We’re trying to work with you.”
He hoists up a heavy resin block that’s been shot with lead and copper bullets, preserving their impact trajectories side by side. The lead explodes into a cloud of fragments while the copper shot neatly peels back on itself like a banana. Copper is more lethal than lead, Sorenson says; it just requires more precision.
It’s hard to guess how California hunters will respond to the lead ban. Over three years of VWS ammo giveaways, Sorenson says, the number of surveyed hunters willing to buy copper bullets has risen from 43 to 68 percent. But the NSSF report uses a survey stat of its own: 13 percent of California hunters would stop hunting if forced to buy copper, which sells for about triple the price of lead.
Kreyenhagen, who represents Carmel Valley and Big Sur on the Monterey County Fish and Game Advisory Commission, says many of his fellow hunters see lead bans as an attack on hunting. That’s evidenced by websites like the NRA-backed HuntForTruth, which blames condor conservation for weakening Second Amendment rights. (Multiple calls to NRA Public Affairs were not returned.)
It would be easier for gun enthusiasts to attack VWS if the nonprofit were against hunting. But Burnett and Sorenson vigorously defend it as the most environmentally sensitive way to manage ground squirrels, deer and wild boar.
Burnett himself grew up hunting white-tailed deer by his family’s harm in the Blue Ridge Mountains. “A hunter,” he says, “that’s a respectable thing.”
~ : ~
Looking through the telescope for Nestling 753 is like searching a page from Where’s Waldo. We finally spot him, a reposing huddle of gray fluff on a gray rock behind a curtain of dead branches.
The chick is about three and a half months old, 16 pounds and with enough down to stay warm on his own. This one’s a fighter, Burnett says: When he was just 5 weeks old, he faced down a raven that tried to attack him. (Watch the video online at www.mcweekly.com/condors.)
He’s the fifth chick to have grown up in this nest, but the breeding pairs have changed a few times. That’s not necessarily normal; lead poisoning forces unnatural shifts in flock hierarchy.
Condors are social, mostly monogamous animals that can live 50-60 years. They co-parent about 18 months for each single chick, brooding around the clock and trading off food runs for weeks.
Lead has killed 50 wild condors to date, Sorenson says, leaving dozens of chicks orphaned and breeding adults widowed. The tragedies play out in slow motion for the VWS condor team, like nature documentary meets telenovela.
Burnett tells me about Condor 171, whose mate flew south of Pinnacles, ate lead-tainted carrion and never came back. An alpha pair decided 171’s nest would make a nice addition to their territory and forced her out, leaving the lower-ranking bird a loner.

Plight of the Condors
“A bird like 171, she might not get another shot,” Burnett says. “She carries that baggage. There might be a form of grieving that goes on.”
Then there’s the saga of Condor 318, profiled on the VWS website. In the top photo he’s in his cave nest at Pinnacles, his plum-colored head poking out from black-draped shoulders. He’s wearing the expression of a content old man, looking through a volcanic-rock window at a sea of tangerine spires.
The middle photo is an X-ray of 318 with an ominous white dot in his gut.
The bottom photo: the .22 caliber bullet recovered from his body.
Condor 318 had been the first breeding male at Pinnacles National Park in 100 years. Pinnacles biologists found him in San Benito County, paralyzed and starving. He died of lead toxicosis at age 10 in November 2012. His surviving mate left the breeding territory.
A flock plagued with lead poisoning is like community at war. Almost every wild condor has faced the sudden losses of its parents, mates or companions. Even the happier stories, those lead-poisoned condors nursed back to health and re-released, pay a social price for disappearing for weeks or months at a time. They have to re-establish their social standing, Burnett says, and try to win back mates. Often, they miss nesting season and have to wait a year for another chance.
High-ranking birds don’t like to show weakness, so they’ll mask the effects of lead poisoning. By the time they lose control of their legs, it’s usually too late.
I look through the telescope at Nestling 753. His parents could be inland right now, eating lead-shot squirrel they’ll regurgitate down the chick’s throat.
“You can’t help but get attached,” Burnett says. “When they fledge, you’re a nervous wreck.”
About a week later he gets the news: Ventana, the first wild-hatched condor in Big Sur, is dead.
~ : ~
Early September sunlight glints off the ocean and is absorbed by the lush lawn at Rancho Grande in Big Sur. The Dave Holodiloff Duo is fiddling a Daft Punk cover while kids paint, their parents hobnobbing with glasses of wine.
The Feathers in Flight gala is VWS’s annual fundraising event. This year’s special guest is Dolly, a captive condor from L.A. Zoo. It’s the first look at a live condor for Assemblyman Mark Stone, D-Scotts Valley, who’s chatting up one of her handlers.
Susan Foreman and Dolly at the event
“Absolutely fascinating bird,” he reflects later. “And huge. You can talk about the wingspan, but until you get up close… ” His voice trails off in wonder.
Inspiring power players like Stone, who backed AB 711, is part of the point. Another is money: Between the gala and a $22,000 donation from The Wine Group and 10-Span Vineyards, VWS netted $65,000 for condor recovery efforts.
Eighteen years in, Sorenson says, VWS’s condor program is now in its final phase. Condor 579, Lupine, was seen in Pescadero last spring, marking the first time in more than a century a condor’s been spotted in San Mateo County.
That’s exciting because Pescadero is only a few miles from the elephant seal rookery at Año Nuevo State Park. The team is trying to push the Central Coast flock coastward by encouraging their taste for marine carrion like beached whales and sea lions.
In a partnership with Monterey Peninsula Regional Park District, where Sorenson’s on the board, VWS has added a new feeding station at Palo Corona Regional Park.
Año Nuevo and San Simeon State Park, by Morro Bay, each host big rookeries of elephant seals, which have particularly low DDT levels. “They would be a fantastic food source,” Sorenson says. “Condors just haven’t found it yet.”
About 5 percent of pups die on the beach. Condors could feast on them.
Luring condors the coast means taking them away from inland habitat – and reducing the population managed by the condor team at Pinnacles National Park.
Denise Louie, chief of resources management at Pinnacles, says she’s OK with that. “Condors are going to go where they’re going to go,” she says. “We need to manage accordingly.”
Pinnacles has four staffers, plus interns and volunteers, dedicated to the condor program. They carefully monitor the birds that nest there, baiting them for health checks and blood draws.
Last spring, 64 percent of the condors they checked had lead poisoning, Louie says. Two died. But it was a good year compared with 2013, when six Pinnacles condors were poisoned to death.
The second part of Pinnacles’ effort is outreach to hunters and ranchers. “We’re in the business of condor recovery. We have to be in the business of talking about lead ammunition,” Louie says. “That is the number-one threat to condor survival.”
~ : ~
During our hike to visit 753, Weekly photographer Nic Coury, toting his gear up crumbly slopes, mutters a critical question: Why should anyone care about the survival of big homely buzzards?
They’re incredibly cool-looking creatures, Burnett says. They perform an important service by cleaning up rotting carcasses. Sorenson jumps in: They’re an indicator species, representing an intact ecosystem. They drive ecotourism.
“You start to say, ‘We don’t need this, we don’t need that.’ At some point it starts to crumble on itself,” he says, tromping deeper into the canyon.
Six weeks later, Burnett updates me on Nestling 753: He’s full-grown, radio-tagged and likely to fledge any day now.
When he does, he’ll forge his place in the Central Coast flock. He’ll fly over the coast and maybe even develop a taste for elephant seal meat. He’ll probably fly east, too, and meet his inland flock-mates at Pinnacles. At some point, he may find a dead ground squirrel and tear off a bite.
If that squirrel was shot with copper, the meat will be safe. If it was shot with lead, it will be poison.

Plight of the Condors
VWS staff will be watching him, holding their breath.

Tuesday, October 14, 2014

Warm and sunny, with a chance of sharks

The juvenile seals are on the beach in numbers now, with more arriving every day. It's a great time to see the seals. So many includes lots of variety in size and development. No mature males with their long proboscis, but so what. There's plenty else to see.

They line the beach. This is the north end. It was a high tide, five feet, but tides can be higher. This one covers the beach at a couple of places. This is a problem during the breeding season, when pups may be washed away. Pups can't swim when they are born.

Young males enjoy engaging each other in battle, even if the stakes aren't very high yet. When they are adults, it's serious. That will come later in the year, in January and February, when only the dominant males get to breed.
Youngsters tussle in the water, too. It's as natural for them to be washing around in the waves or under water as it is on land.
Less happily, seals show evidence of shark attacks. Juveniles make a good, fat meal for sharks, and this is an important feeding time for sharks along the central coast. Thus far, scientists haven't found sharks feeding much in this area, but it's busy in the Farallon Islands and at Ano Nuevo. For this seal, it was a big bite.

She went back into the water and wasn't sighted again. She may have died but it's not unknown for seals to survive astonishing wounds. I saw this seal feeding her pup last year.