Sardines move north due to ocean warming

Original post: Phys.org

Sardines, anchovies and mackerels play a crucial role in marine ecosystems, as well as having a high commercial value. However, the warming of waters makes them vanish from their usual seas and migrate north, as confirmed by a pioneering study analysing 57,000 fish censuses from 40 years. The researchers warn that coastal towns dependent on these fishery resources must adapt their economies.

The continued increase in water temperature has altered the structure and functioning of marine ecosystems across the world. The effect has been greater in the North Atlantic, with increases of up to 1.3 ºC in the average temperature over the last 30 years.

This variation directly affects the frequency and biogeography of a group of pelagic fish, which includes the sardine (Sardina pilchardus), anchovy (Engraulis encrasicolus), horse mackerel (Trachurus trachurus) and mackerel (Scomber scombrus), among others, which feed off phytoplankton and zooplankton and that are the staple diet of large predators such as cetaceans, large fish and marine birds. These fish also represent a significant source of income for the majority of coastal countries in the world.

Until now, scientists had not managed to prove whether the changes observed in the physiology of the pelagic fish were the direct result of the water temperature or if they were due to changes in plankton communities, their main food source, which have also been affected by global warming and have changed their distribution and abundance.

The new study, published in Global Change Biology and that has developed statistical models for the North Sea area, confirms the great importance of sea temperatures. “Time series of zooplankton and sea surface temperature data have been included to determine the factor causing these patterns”, Ignasi Montero-Serra, lead author of the study and researcher in the department of Ecology at the University of Barcelona, explains to SINC.

Bioindicators of the health of the sea

To demonstrate the consequences of the warming of the seas, the research team analysed 57,000 fish censuses from commercial fishing performed independently along the European continental shelf between 1965 and 2012, extracted from data provided by the International Council for the Exploration of the Sea (ICES).

The study, the first to be carried out on such a large time scale and area, allows for the dynamics of this species to be understood in relation to the rapid warming of the oceans that has been happening since the eighties.

The results reveal that sardines and other fish (with fast life cycles, planktonic larval stage and low habitat dependence) are highly vulnerable to changes in ocean temperature, and therefore represent “an exceptional bioindicator to measure the direction and speed of climate change expected in the near future”, points out Montero-Serra.

Subtropicalization of North Sea species

Due to the accelerated increase in temperature of the continental seas, sardines and anchovies (with a typically subtropical distribution) have increased their presence in the North Sea “even venturing into the Baltic Sea”, confirms Montero-Serra, who adds that the species with a more northern distribution (like the herring and the sprat) have decreased their presence.

The analysis is therefore a clear sign that species in the North Sea and Baltic Sea are “becoming subtropical […] where sardines, anchovies, mackerel and horse mackerel, more related to higher temperatures, have increased their presence”, says the researcher.

This is due to the pelagic fish being highly dependent on environmental temperatures at different stages of their life cycle: from reproductive migrations and egg-laying, to development and survival of larvae.

According to researchers, the changes in such an important ecological group “will have an effect on the structure and functioning of the whole ecosystem”. The expert warns that coastal towns that are highly dependent on these fishery resources “must adapt to the new ecological contexts and the possible consequences of these changes”, although they still do not know the scale of the socio-economic and ecological repercussions.

Scientists: Warm waters, scarce prey likely cause of California sea lion strandings

The Press Democrat.com

California sea lions swim at the Marine Mammal Center in Sausalito, Tuesday, February 3, 2015. (Crista Jeremiason / The Press Democrat)

An intensifying spate of sea lion strandings on the California coast is likely caused by a shift in winds that has warmed coastal waters, making prey scarce for sea lion mothers and interfering with their ability to feed their pups, federal scientists said Wednesday.

The announcement marked the clearest answer yet to what might be affecting the sea lions, hundreds of which have come ashore malnourished and severely underweight in recent months.

With more than 940 animals, mostly pups, already admitted to rehabilitative care over the past several weeks, the state’s marine mammal centers are nearing capacity and running through resources, said Justin Viezbicke, California Stranding Network Coordinator for the National Oceanic and Atmospheric Association.

Many sea lions won’t be saved.

Yet NOAA scientists said the situation is less alarming than would appear and doesn’t look to be tied to a disease or new malady. Instead, it likely reflects the sea lion’s acute sensitivity to a change in ocean circulation patterns. The altered winds have bathed the coast in warm water — 2 to 5 degrees warmer than usual — and made foraging for redistributed fish species more of a challenge.

“It’s unlikely to have any really critical drop in the total population,” said Sharon Melin, a wildlife biologist with NOAA’s National Marine Mammal Laboratory at the Alaska Fisheries Science Center in Seattle.

There remain many unknowns, however, including how bad the situation will get before it starts getting better. Experts said they do not expect the situation to turn around for at least a few months.

Sea lions serve as an indicator species, Melin said, and are sometimes among the first and most visible marine creatures to reflect something amiss in the ocean environment. Their recent plight is one in a series of die-offs and stranding events beginning in 2009 on the heels of a rapid ocean warming. The population of their core prey has been somewhat diminished over the same time period, she said, so scientists will be looking for longer term implications.

January strandings were more than five times the historic average and more than twice the rate observed in 2013, when NOAA declared an Unusual Mortality Event, or UME. More than 1,100 sea lion strandings were recorded that year.

This year has not been declared a UME yet, though observations so far suggest it may be an even worse year, with data collected from sea lion rookeries in the Channel Islands during September and February showing that pups born last summer were already severely underweight, and in many cases, continued to lose weight over the winter, Melin said.

Most turning up on the coastline now are around 8 months old and should still be with their mothers, but appear to have weaned early, leaving the Southern California colonies in search of food, she said. Many are starving, too young to have developed the necessary skills to survive.

Scientists believe the root problem is the inability of their mothers to find sufficient food to nourish their young, most likely because the large area of warm water off the coast has driven fish and other marine life to other areas.

Yet satellite tags on some of the female sea lions who bore pups last year indicate they are staying within their usual foraging grounds, suggesting they may be having to dive deeper and work harder to feed, and thus are leaving their pups for longer periods, Melin said.

Pups left long enough will be so hungry they go off on their own to seek food, she said.

If so, this year’s event is similar to 2013, in which unavailability of prey was determined at least partly responsible. Though sea lions are opportunistic feeders, their core diet includes species rich in fatty acids like Pacific sardines, northern anchovies, rockfish, Pacific hake and market squid, some or all of which may be in short supply, Melin said.

Many pups coming ashore have secondary infections, like pneumonia, but testing on those that have not survived has not revealed evidence of an infectious disease outbreak or harmful algae blooms, which also are potential risks, scientists said.

Nate Mantua, a NOAA climatologist, said a period of strong southerly winds and weak northerly winds has spread warm water north and depressed the upwelling of cold water from deep ocean levels toward the surface.

He said the shift reflects the vagaries of weather — not more permanent climate change.

The warmer off-shore currents have coincided with a variety of shifting marine populations, causing some species to turn up in areas that are not part of their traditional habitats, Mantua said.

“There’s just a whole suite of different animals — some are really good swimmers and some are really weak swimmers — that have changed their distribution,” he said.

Sea lions, which are protected under the 1972 Marine Mammal Protection Act, generally have thrived in recent decades but had a rough time of it since 2009. It may be that the population has reached the carrying capacity of the coast, meaning that the current problems finding sufficient food are nature’s way of restoring balance, Melin said.

Most sea lions are born in June and are totally dependent on their mothers for the first six months of their lives, experts say. They generally remain with their mothers until about 11 months of age, when they are weaned.

Where some pup strandings occur every year, it’s usually around May and June, when pups are just beginning to forage on their own, with varying degrees of success, scientists said.

This year’s strandings began months earlier, in December and January, and have accelerated in recent weeks, resulting in reports like one out of San Francisco, where last week a pup strayed onto Skyline Boulevard, about 1,000 feet and up a hill from the water. Another report this week described an emaciated young sea lion wandering into a Marina del Rey apartment complex.

Though most of the strandings have occurred in Southern California and, to a lesser degree, on the Central Coast, the Marine Mammal Center in Sausalito, the world’s largest, has been at the forefront of providing care.

It is now responding to up to 15 ailing sea lions daily, and has more than 130 sea lions in rehab at its Marin Headlands facility, spokeswoman Sarah van Schagen said.

About 550 total are in the care of a half-dozen marine mammal centers up and down the coast.

Though the Sausalito center still has room, the growing number of strandings is making it harder and more time-consuming for rescue personnel to respond to reports. Mantua pleaded with the public to be patient with those doing their best to tend to the animals that can be saved.

Anyone who sees a stranded sea lion should report it by calling the Marine Mammal Center’s 24-hour rescue hotline at 415-289-SEAL (7325) and then leave the animal alone, avoiding human or pet contact that may contribute to its stress.

Mantua encouraged anyone interested in aiding the cause to donate time, supplies and money to facilities like the Marine Mammal Center.

View original article: The Press Democrat.com

California sea lion crisis: Warmer seas may be to blame

Copyright © 2015, Los Angeles Times

Nearly 1,000 abandoned California sea lions have washed ashore this year in what rehabilitation centers say is a growing crisis for the animals.

Emaciated and dehydrated sea lions, mostly pups about 8 months old, have been admitted in record numbers to facilities up and down the California coast.

As of now, there are 550 sea lions at facilities statewide, according to NOAA Fisheries, which addressed the crisis Wednesday morning during a conference call with media.

It’s the third straight year for record numbers of sea lion strandings in the state.

Earlier this month, researchers from the National Oceanic and Atmospheric Administration’s National Marine Mammal Laboratory visited sea lion rookeries on the Channel Islands, where most of America’s sea lions breed.

They measured and weighed pups and found them to be considerably underweight. Their average growth rate also was alarmingly low.

“It’s the lowest growth rate we’ve ever observed,” said Sharon Melin, NOAA Wildlife biologist with the National Marine Mammal Laboratory.

The pups’ weight was similar to what was seen in 2013, the year of an “unusual mortality event” for sea lions, and during the 1998 El Niño, which was another difficult year for the mammal.

A UME is characterized by an unexpected number of strandings and significant die-off of a marine mammal population.

Although scientists are still awaiting data from research done on the islands, NOAA Fisheries says warmer-than-average sea surface temperatures along the California coast in fall 2014 may be a factor.

The warmer water could have affected the sea lions’ prey resources. Female sea lions may be having to expend more effort and time to get food, so pups are abandoned.

According to multiple California marine mammal centers, they are seeing a much larger number of sea lions in the first two months of 2015 than in 2013.

“The sea lion pups arriving at the Marine Mammal Center may look like barely more than skin and bones, but these are the lucky ones” because they receive treatment, said Shawn Johnson, director of veterinary science at the Marine Mammal Center in Sausalito, Calif.

Read te original story: Los Angeles Times

For Rockfish, A Tale Of Recovery, Hidden On Menus

Preface: The authorized, State approved market name for 13 species of rockfish in California is “Pacific red snapper”, or Pacific snapper.

Donna Schroeder/From ‘Probably More Than You Want to Know About the Fishes of the Pacific Coast’/Courtesy Milton Love

A school of vermilion rockfish. After being depleted decades ago by overfishing, rockfish — a genus of more than 100 tasty species — have made a remarkable comeback.

 
For West Coast commercial fishermen and seafood lovers, there is reason to cheer. Rockfish, a genus of more than 100 tasty species depleted decades ago by excessive fishing, have rebounded from extreme low numbers in the 1990s.

It’s a conservation and fishery management success story that chefs, distributors and sustainable seafood advocates want the world to hear.

The rub? It’s hard to communicate this success if purveyors continue to misidentify the fish, as many do.

Now, this isn’t necessarily a case of retailers and chefs being shady. A big problem, says chef Rick Moonen, owner of RM Seafood in Las Vegas, is that fish go by different names in different places. Take rockfish, for example.

“On the East Coast, they call striped bass ‘rockfish.’ You offer them a chilipepper,” Moonen says, citing the name of one rockfish species, “and call it a ‘rockfish’ and they’ll think they’re getting a striped bass.”

Moonen is well known as a sustainable-seafood advocate. And he’s eager to tell the story of rockfish’s comeback, a result of tightened fishing restrictions and a reduction in the number of commercial trawlers raking the ocean bottom in pursuit of the buggy-eyed, spiny-backed fish.

But he says many diners are only familiar with a handful of fish species, and rockfish can sound “like an animal from the Flintstones cartoon.”

If the goal is to get consumers to develop a taste for these fish, Moonen suggests, you’ve got to market it to them in an appealing way. So for now, on his menu, rockfish are still being sold as “Pacific bass.”

“That’s … the Trojan horse we use to get this fish into people’s mouths,” he says. That said, Moonen says he plans to transition to using real names for rockfish.

Indeed, rebranding fish species with more appealing market names is a common and accepted practice in the seafood industry. Tooth fish are sold as Chilean sea bass, sablefish as black cod and slime head as orange roughy.

In these cases, it’s not quite fraud, because consumers understand what each market name means. As Derek Figueroa, chief operating officer with Seattle Fish, a distributor in Denver, observes, “It’s like asking for a Kleenex and getting some other tissue. It might not be what you asked for, but it’s what you had in mind.”

Not always, says Kim Warner, a senior scientist with the environmental group Oceana. She notes that rockfish is sometimes sold as snapper — but “snapper” is the name of another group of fish, which live in warm waters and are exceptionally tasty.

“What if someone who is familiar with real snapper comes to California?” asks Warner. “They’ll think they’re getting snapper. This absolutely confuses people.”

The debate over what to call rockfish comes as American consumers are increasingly demanding accurate information about their food and where it came from. And even if they don’t, correctly identifying fish on menus and in markets is the first step toward creating traceability in the often deceptive and murky fishing industry, says Sheila Bowman of the Monterey Bay Aquarium’s Seafood Watch Program.

“The only way to recognize and appreciate these fish is to start calling them by their proper names,” says Bowman.

Bowman says telling the story of West Coast rockfish is important, because it could inspire fishery managers elsewhere to use similar strategies to rebuild other depleted fisheries — such as the beleaguered Atlantic cod.

Oceana’s Warner notes that some instances of seafood mislabeling — such as calling farmed fish “wild,” or serving up a fish containing high mercury levels under an ambiguous label — are deceitful attempts to hide traits that might be seen as undesirable.

But the case of the West Coast rockfish fishery offers much to be proud of, she says — so chefs and vendors who pass rockfish off as something else are shooting themselves in the foot.

“If they’re celebrating that rockfish are doing well, why call them snapper?” Warner says. “You lose the story you’re trying to tell.”

Bowman says that on regular strolls through the seafood markets of Cannery Row, in downtown Monterey, Calif., she sees rockfish of all colors labeled as “snapper” and “rock cod.” Sometimes, chefs and vendors avoid the fishes’ real names because they are a mouthful for diners — like vermillion rockfish, bocaccio rockfish, chilipepper rockfish and shortbelly rockfish. But Figueroa at Seattle Fish says he’s excited to start using these exotic — and accurate — names.

And a little tableside education could quickly help consumers get over the unfamiliarity factor, adds John Rorapaugh, owner of a seafood wholesaler and distributor in Washington, D.C., called ProFish.

“I think it’s more interesting to use the real names,” Rorapaugh says. “If you have thornyhead rockfish on the menu, it will start a conversation.”

And if consumers start asking for these mild, white fish species by name, says Bowman, it could help boost demand — and prices — for rockfish. She says that could be good for both fish and fishermen.

“If rockfish fishermen are happy and making money, other fishermen will see that [the recovery efforts used for West Coast rockfish] could work in other places,” Bowman says. “But if fishermen are just getting a couple of bucks a pound for these fish, then the effort we made to bring this fishery back won’t be worth it.”

View original article here.

Elephant Seals Battle for Love With Mating Songs and Bravado

Lauren Sommer, KQED Science

Editor’s Note: This story won a national Edward R. Murrow Award last year for Use of Sound. We bring it back to you as our Valentine from KQED Science. 

A male northern elephant seal calling at Año Nuevo State Reserve. (A. Friendlaender)

Love is in the air on California beaches this time of year, when northern elephant seals arrive by the thousands for breeding season. Males make plenty of noise at Año Nuevo State Reserve, north of Santa Cruz, but it sounds more like a chorus of motorcycles than the sultry sounds of Annie Lennox.

Now, researchers at UC Santa Cruz are decoding this complex communication system and learning how males use it to boost their reputation.

Elephant seals spend most of the year alone in the Pacific Ocean, so there’s plenty of action packed into the two months they’re on land every winter. “That’s mating behavior,” says naturalist Lisa Wolfklain, pointing at two elephant seals in a sea of hundreds of males, females and pups.

Male elephant seals are the size of an SUV — fifteen feet long and 4,000 pounds. They’re known for their proboscis, the huge, fleshy nose that hangs over their mouth. There are plenty of available females this time of year, but most males will strike out. The dating scene is controlled by alpha males.

“The alpha strategy is to be dominant over a group of females, the harem,” says Wolfklain. “And they want to have the first right to mate.”

You can spot the alpha males right in the middle of their groups of 10 to 100 females. The other males, known as betas, are on the outskirts, just watching, waiting for their chance.

“So this guy’s coming in,” says Wolfklain, pointing at one beta male moving quickly toward a female. The alpha male perks up and snorts a warning with customary bravado. Sometimes the fight ends there, but not this one.

“Ooh, now they’re hitting with their heads,” the commentary continues, as the two lunge at each others’ chests. A few strikes seem to be enough for the beta male and he retreats.

These fights can be bloody and all the while, other males are taking advantage and sneaking in. It adds up to a very stressful time for male elephant seals.

It’s All About Reputation

“It’s not advantageous for males to fight all the time,” says Caroline Casey, a researcher at UC Santa Cruz. She says fights can be risky. “Sometimes they can result in death and we’ve seen that,” she says.

Elephant seals also don’t eat while on land, so they need to conserve energy. Casey says, as with humans, one way to avoid fighting is communication. But until now, no one was really sure what the males were saying to each other. So, she and her colleagues have been studying a patch of beach with about 50 males.

“We have come up with this ranking system where we assign each male a score,” she says. It’s similar to systems used in professional sports, where the males win or lose points with every fight. Casey and her team also recorded the males’ calls and found remarkable differences.

One beta male, X579, has a call that ends in a flourish. “His call, to me, is my favorite,” she says. “He always has this really lovely note at the end of it.”

X579 was a beta male with a lot of competition. “He tends to vocalize and challenge everybody right when he gets there,” Casey says. He challenged GL, an alpha male with a very short, staccato call.

“That is what’s so incredible,” Casey says. “All of the animals sound completely different from one another.” What’s more, Casey’s team found that each male seems to use the same call year after year, whether he has a harem or not. It’s their signature call – and they flaunt it.

“A larger, more dominant animal will come up to a smaller animal, maybe beat him up a little bit,” says Casey, “call at him before and after, like, ‘Hey, this is me. I’m Bob. Don’t mess with me.’”

It’s all about spreading your reputation around. “That’s called associative learning and that’s very unique among marine mammals,” Casey explains. “That means that every male has the potential to be learning every other male based on their acoustic signature at that site.”

These complex communication systems have been studied in songbirds and other animals, but Casey says less is known about marine species. “I think it’s just a piece of larger puzzle in understanding how these animals breed and how they’re going to survive.”

A century ago, elephant seals were hunted to near extinction for their blubber. Fewer than 100 lingered off the coast of Mexico. With protective laws in place, today there are more than 150,000 northern elephant seals — and growing.

That’s good news for Casey’s loner elephant seal X579. This year, he’s an alpha male for the first time. As for the others, there’s always next year.

Read the original post here.

Mike Hale, The Grub Hunter: Don’t slam the sardine

Smaller fish such as sardines and herring are less vulnerable to pollutants. (Bob Fila — Chicago Tribune file)

By Mike Hale, Monterey Herald

I live for Sardine Tuesdays, those rare occasions when Local Catch Monterey Bay offends some of its members by highlighting those small, oily “trash” fish that belong on the end of a hook — not in a fry pan fouling the air within two square blocks.

The sign-out sheet at my pickup location always includes more than a few persuasive scribbles from disappointed members urging someone — anyone — to take their share.

I always oblige. Then I tote home my double dose of sardines — meeting the cold glare of my fish-phobe wife and the delirious purr of our rotund Sopa, who creates a happy tangle of orange fur around my ankles.

Sardines and other small fish at the bottom of the food chain (herring, mackerel, smelt, anchovies) often end up in pet food, but in the right hands they are a tasty, healthful addition to the human diet (a fact ridiculously obvious anywhere outside our Fast Food Nation).

When Local Catch offers the smaller-sized sardines as it did last week, I prepare my home for a massive fish fry by opening my kitchen windows. It’s a simple process: I liberally season the cleaned, headless sardines before dredging them in flour and frying them in vegetable oil. After a spritzing of lemon juice, I hold these crispy beauties by the tail and eat them whole (the tiny bones practically dissolve upon cooking).

If that seems like a lot of trouble, order them out. Oddly enough, the former Sardine Capital of the World has traditionally boasted very few restaurants that serve these undervalued and underutilized fish (and believe it or not, the Sardine Factory has never served sardines).

But the tide is turning. Heading to Fisherman’s Wharf provides options: Domenico’s offers a fried anchovy appetizer and olive-oil marinated, grilled local sardines served with a Sicilian salsa; Abalonetti Bar & Grill grills its local sardines, topped with a spicy marinara. Off the pier: Crystal Fish in Monterey serves a fine sardine sushi; Lokal in Carmel Valley often adds to its menu tasty sardine sandwiches called bocadillos, slathering the bread with a pungent mojito aioli; jeninni kitchen + wine bar in Pacific Grove rolls out bruschetta with anchovies; and Mundaka in Carmel right now offers Spanish mackerel escabeche, a method where the fish is cooked before pickled.

Boats are pulling Spanish mackerel out of the bay now, and Mundaka chef Brandon Miller seasons them with fennel, black pepper and cumin before roasting. He then sautés vegetables, adding water and vinegar to create a pickling liquid he pours over the fish.

When smelt are running in San Francisco Bay, Miller will source them from his hometown and serve what he calls “fries with eyes.” He dredges the whole smelt in flour and deep-fries until crispy, serving them with a side of squid ink aioli.

“You can’t just eat all the big fish, because there is only so many of them in the ocean,” he said. “I like to target these little fish. They are delicious and really good for you.”

Cardiologists light up at the subject. Sardines and their brethren are full of heart-healthy omega-3s, and not full of toxins (such as mercury) that can build up in large fish such as tuna. They are also chock-full of fat-fighting compounds that help stabilize blood sugar, and rich in coenzyme Q10, vitamin B12, selenium, calcium, phosphorus and vitamin D.

Without a doubt, sardines are stinky, slimy, slippery and seemingly indigestible. But look closer, climb down the food chain and give them a try anyway. Open the windows, put on a pot of boiling vinegar and cause a stink.

Read the original post MontereyHerald.com.

Pink sea slugs swarming northwards as ocean temperatures rise

The bright pink sea slugs are typically found in Southern California, but have been found moving farther and farther north as ocean temperatures increase, possible due to global warming.

Central and Northern California are beginning to take on a pink hue as Hopkins’ rose sea slugs take over — something that scientists say may be due to global warming.

The increasing global temperatures have caused an explosion in the population of the Hopkins’ rose nudibranch beyond Southern California, where it is typically found. Usually, it is extremely uncommon north of San Francisco, but scientists are spotting them in tide pools far north of that, according to a Santa Cruz Sentinel report.

Rare wind patterns that scientists have yet to explain have caused temperatures in West Coast oceans to rise, which has lured the sea slug far best its typical range.

And it’s not the only unusual visitor to the area, with fisherman in San Francisco capturing a sea turtle back in September that in the past would have only been found off the coast of Mexico or the Galapagos far to the south. Meanwhile, humpback whales and dolphins are being spotted on a regular basis in the Monterey Bay, according to the report.

Scientists say the waters off the coast are about 5 degrees higher than they normally are for most of 2014, and it has just been increasing in warmth, according to Logan Johnson, a National Weather Service forecaster in Monterey, who was quoted in the report.

Currently, waters in the Monterey Bay are running in the high 50s, and it’s staying there.

Typically, such temperatures would suggest that El Nino is on its way. The current warming is being created by what is known as upwelling, which is when Northwesterly winds blow away water at the surface, causing colder waters farther down to replace it — but scientists haven’t spotted those winds.

John Pearse, an ecology and evolutionary biology professor at the University of California Santa Cruz, said another warm phase is beginning, although scientists have no way of know if this is part of normal oscillation or if it’s global warming, according to the report.

Colder currents could be causing the sea slug’s range to shrink because their prey — rose-colored encrusting bryozoan, a moss-like life form — can be found up and down the Pacific Coast as far north as British Columbia. Now that northward currents are carrying the species larvae to tide pools, upwelling isn’t washing them away.

Read original post: ScienceRecorder.com

California sea lions in trouble

In mid-December, when moms were raising pups down south, 700-pound males hauled out onto the Moss Landing Harbor visitor dock. One fell asleep with its face in the water. (Leslie Willoughby Contributed) right).

MOSS LANDING — When baby sea lions are healthy, the curious and bright-eyed creatures sit up on their front flippers and take in the world around them. When humans approach, they skedaddle and leave nothing behind except a fishy, musky smell.

But along the Central Coast, sea lion pups in recent years increasingly have been found stranded — and they’re down to skin and bones. “Sometimes they could barely lift their heads, and they were reluctant to move, even when approached,” said Claire Simeone, a conservation medicine veterinarian at the Marine Mammal Center in Sausalito. “I could see the outlines of their hipbones and their shoulders.”

Even in a good year, a sea lion pup has only a 70 percent chance of reaching its first birthday. But in 2013 only 30 percent survived. And by May of that year, almost 1,500 were stranded along the California coast — up to 10 per day along the Monterey Bay shoreline.

To marine biologists, the deaths were the clearest sign yet that California sea lions, whose numbers skyrocketed for decades, are now smacking up against the limits of their environment.

The stranded pups should have been with their mothers, but the mothers apparently couldn’t get enough nutrition to support them, said Sharon Melin, a researcher with the National Oceanographic and Atmospheric Administration.

One reason was that the California Current, which flows south along the coast, moved farther offshore, making sardines and anchovies less available. Working harder to find food, the moms ate more market squid and rockfish, Melin said, and this change in diet may have reduced the quality of their milk.

The number of pups rescued from Sausalito to San Luis Obispo by the Marine Mammal Center, which has a facility in Moss Landing, jumped from 35 in 2012 to 111 in 2013. And last year that number increased to more than 239.

“We’re seeing another year of low weight and small body size,” Melin said. “We’re telling everyone to brace for more sea lion pups on your beaches.”

Although California sea lions have never been considered endangered, they have been hunted throughout history. Early Californians killed them for food; in the mid-19th century the mammals were hunted for their oil and hides. And from the 1930s to 1950s, they were turned into pet food.

According to UC Santa Cruz scientists, the Montrose Chemical Corp. from 1949 to 1970 manufactured DDT and dumped thousands of tons of the insecticide residue through sewage outfalls near the Channel Islands, the main sea lion breeding area in the U.S. During the late 1960s, scientists found hundreds of premature sea lion pups at the islands, and one year half of all pups died. Tests showed that moms that miscarried their pups had at least eight times more DDT in their tissue than did moms that gave birth to fully developed pups.

Two key events, however, soon improved the sea lions’ fate.

Montrose stopped releasing DDT into the breeding area in 1970, and two years later Congress passed the Marine Mammal Protection Act. The number of pups, which had hovered around 11,000 during the mid-1970s, doubled by 1993 and exploded to 60,000 by 2009, according to the National Marine Fisheries Service.

But the population is now leveling off.

Anticipating more starving pups this winter, the Marine Mammal Center has been ordering medications and training rescue volunteers, Simeone said.

In addition to the pups, the center rescued 180 adult sea lions in 2013 and 420 last year. Some were afflicted by hookworm or another parasite, Toxoplasma gondii, which is carried by cats. Others had contracted diseases such as leptospirosis, a bacterial infection that affects their kidneys. And some were poisoned by a nerve toxin called domoic acid, which is found in increasingly widespread blooms of a particular type of algae, according to NOAA. Sea lions eat fish that eat the algae.

Domoic acid also sickens humans if they eat shellfish that have eaten the toxic algae. When the Marine Mammal Center finds sea lions poisoned by domoic acid, the staff works with health departments to locate the algae and ban people from collecting shellfish nearby.

Marine scientists say that sea lions are the ocean’s canaries in a coal mine. “They tell us so much about the health of the ocean,” Simeone said.

Many fishermen and harbormasters, however, aren’t as enamored with the species.

“If sea lions are around, a salmon sports fisherman doesn’t stand a chance,” said Roger Thomas, the president of the Golden Gate Fishermen’s Association. “A sea lion will tear a fish right off the line and the angler is left with just a head.”

Thomas has been involved in recreational salmon fishing since he started in Monterey Bay in the 1950s. He has observed the sea lion population boom and wonders whether that may be contributing to pup strandings, he said.

At Moss Landing Harbor, the 700-pound mammals cause roughly $100,000 damage each year, said Linda McIntyre, the harbor’s general manager.

Between 200 and 2,000 sea lions vie for dock space around Monterey Harbor, said Harbormaster Steve Scheiblauer. One year they sank five vessels.

When someone tries to get to a boat, the animals usually move out of the way, but they leave vomit and excrement behind. And, he said, because there are so many of them, they are entering places they would ordinarily avoid.

“Most people love the sea lions and want to protect them,” Scheiblauer said. But when he thinks about their future, he said, “I worry that nature will take its course through disease and famine. That would be a tragedy for the animals.”

Read original post Contra Costa Times.

Atlantic, Pacific Fish Face Mixing as Arctic Warms

The gradual warming of the Arctic Ocean over the next century will weaken a natural barrier that has separated fish from the Atlantic and Pacific Oceans for millions of years, leading to a mixing of species that could make life difficult in fishing communities from Alaska to Norway.

A new study by scientists in Denmark combined current models of climate change, and the biological water temperature and food requirements for 520 fish species native to the two oceans. The report forecast changes in the range of these fish in five-year increments from now until 2100, when the world’s oceans are expected to heat up globally by an average 4 degrees Celsius (7 degrees Fahrenheit).

“There will be an interchange of the fish communities between those two seas,” beginning as soon as 2050, said Mary Wisz, lead author on the report in Nature Climate Change and a senior ecosystem scientist at Aarhaus University in Denmark. “We know from historical examples that this kind of interchange, when biotas have been separated over long evolutionary time scales, can have huge consequences.”

In this warmer future, fishermen based in Kodiak, Alaska, could be pulling up Atlantic cod, a prized species normally caught off New England and Northern Europe. A similar change has already started off the coast of Greenland, where fishermen in the last five years have been catching larger numbers of Atlantic mackerel, which prefers more temperate water.

Wisz and colleagues say that by 2100, up to 41 species could enter the Pacific and 44 species could enter the Atlantic, through Arctic water passages over Canada or Russia. This interchange will have ecological and economic consequences to ecosystems that at present contribute 39 percent to global marine fish landings.

While some fishermen may benefit from the new catches, scientists warn that it’s hard to predict exactly what kind of fish will take over, and which will be driven away by the newcomers. It’s also possible that several kinds of fish could compete for the same food source – smaller fish, marine shrimp or larvae, for example, leading to a big reshuffling of the existing marine food chain.

“Some species when they come together they get along,” said Peter Moller, curator of fishes at the Natural History Museum of Denmark and another author on the new report. “But of course the Atlantic cod has the potential to become extremely numerous and dominating if it has the right conditions. There is speculation if it gets to a new place, it can be a real game-changer.”

Moller said the cod is an especially voracious predator of smaller fish, and could impact commercial landings of Alaska Pollock, for example. Around 3 million tons of Alaska pollock are caught each year in the North Pacific from Alaska to northern Japan. Alaska pollock is the world’s second most important fish species in terms of total catch.

Jason Link, senior scientist for ecosystem management at the National Oceanic and Atmospheric Administration, agreed that the mixing of species will cause changes in the food web in both oceans, but it’s hard to predict exactly how it will shake out.

“Another issue not noted in this paper is what happens in the ecosystem that these fish move out of, do they remain there or do other species replace them from the south?” Link said via e-mail.

Another thorny issue is how to manage fishing boats who will likely be plying the rugged Arctic Ocean once commercial harvests become feasible.

“This work raises important ramifications for fishes in response to changes in sea ice,” Link said.

Wisz and Moller say their next task is to look at realistic scenarios of predators and prey in the new warmer Arctic ecosystem.

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Monterey Bay Aquarium testing the waters with open source camera

Mercury News | By Samantha Clark, Santa Cruz Sentinel

Rockfish researchers recover a frame carrying a small SeeStar system and a larger, older camera system after a deployment in Monterey Bay. (Francois Cazanave — MBARI)

MOSS LANDING — Ocean research can be a costly voyage. Scientists often need expensive, high-tech, complex equipment, which some research institutions might lack the funds to build or buy.

So engineers at the Monterey Bay Aquarium Research Institute designed a simple underwater camera and lighting system that is made mostly of hardware store materials. And all for $3,000.

Most oceanographic camera systems cost $5,000 to $20,000 and require ships and cranes to carry the heavy equipment.

Any researcher can find the directions online to build the camera system themselves. It takes stills and video and operates as deep as 1,000 feet for months at a time.

“There is a movement to have open source oceanographic equipment,” said Chad Kecy, lead designer and MBARI engineer. “Anyone could take our designs and modify them for specific needs they have. It’s just a less expensive and easier way of getting cameras in the water.”

The project began in 2012 when MBARI marine biologist Steve Haddock wanted a cheap and easily deployable camera for researchers around the world to document jellyfish blooms. He also wanted versatility. A lightweight system needed to attach to a pier, be mounted on the seafloor and carried by a robotic submarine.

The SeeStar’s relatively simple design met Haddock’s criteria. It’s a GoPro camera with longer battery life and controllable lights all housed inside standard PVC pipe with commercially available electrical cables.

“We chose materials intentionally that people would be able to purchase at a local hardware store,” Kecy said. “The mechanical parts, we tried to get them off the shelf. We were thinking about cost at every step of the way.”

Researchers have begun testing the waters with the SeeStar system. Instead of using their bulky and expensive cameras, scientists with the Nature Conservancy and Moss Landing Marine Laboratories opted for multiple SeeStar cameras to capture video in Rockfish Conservation Areas along the west coast and seafloor animals under the ice in Antarctica.

The California Wetfish Producers Association used SeeStar to photograph the eggs and larvae of market squid. While the squid make up a large and economically important fishery in California, scientists don’t know much about what they do when they’re not spawning or the best conditions for spawning.

“If you were to charter at ROV (remotely operated vehicle), I’ve heard it’s like $10,000 a day, which is outrageous and beyond our budgeting,” said Diane Pleschner-Steele, executive director of the nonprofit. “Putting together our own SeeStar camera is going to give us a lot of opportunity to understand what’s going on within their life cycle. Just by looking at a photograph, we were able to tell which eggs were about to hatch.”

However, the designers want camera to be even more accessible. The circuit board that controls the system is still complex enough leave non-engineers scratching their heads, so Kecy is looking to replace it with the popular Arduino microcontrollers this year.

“The camera system could have uses beyond marine research and could be used for monitoring anything long term,” Kecy said. “Because it’s open source, inexpensive and really easy, it just presents an opportunity for more researchers to cameras out in the water.”

—— (c)2015 the Santa Cruz Sentinel (Scotts Valley, Calif.) Visit the Santa Cruz Sentinel (Scotts Valley, Calif.) at www.santacruzsentinel.com