Point Blue and NOAA Farallones crew tracks predators, prey in changing ecosystem

 

 

A research team hauls in nets designed to collect krill and other small sea creatures in the Gulf of Farallones National Marine Sanctuary.
Photo credit: Joe Rosato Jr.

Dolphins, Pelagic Red Crab, Sun Fish Point to El Nino Coming to Northern California
[see video]

By Joe Rosato Jr. NBC Bay Area News September 30, 2015

The subjects of science are often witnessed through microscopes, tiny squiggly things writhing in a petri dish. But last week as a large research boat drifted through the Gulf of Farallones National Marine Sanctuary, science was getting scrutinized through binoculars and even the naked eye. Joe Rosato Jr. reports. (Published Wednesday, Sept. 30, 2015) The subjects of science are often witnessed through microscopes, tiny squiggly things writhing in a petri dish. But last week as a large research boat drifted through the Gulf of Farallones National Marine Sanctuary, science was getting scrutinized through binoculars and even the naked eye. For the 12th year in a row, researchers from Point Blue Conservation Science, the Gulf of Farallones and Cordell Bank Marine Sanctuaries were spending 10 days on the ocean outside the Golden Gate Bridge taking a scientific snapshot of ocean life. “Our goal is to understand how ocean conditions affect food for birds and whales,” said Jaime Jahncke of Point Blue.
Over several days the team collected krill samples, tested for signs of ocean acidification and attempted to lay eyes on as many critters as possible.
“Our sampling effort looks at birds, mammals, krills, boat activity ,” said Jan Roletto, research coordinator for Gulf of Farallones National Marine Sanctuary..
But this year’s gathering turned-up some unusual phenomenon, which scientists believe are signs of an El Nino year – which draws unusually warm waters to Northern California. For the first time in decades, scientists saw schools of hundreds of common dolphins which aren’t common to the Bay Area, but rather the typically warm waters of Southern California. “It’s a sign the water is more warm than we normally see,” Roletto said. “And that’s a sign of El Nino.” Scientists have recorded large pockets of warm water along the West Coast over the last two years – which they’ve affectionally nicknamed “the blob.” “This year has been particularly interesting,” Jahncke said. “The ocean has been really warm because of ‘the blob.’ “….

 

 

 

Photo: Michael Macor, The Chronicle Capt. Chris Eubank (left) and researcher Danielle Lipski survey the ocean aboard the research vessel Fulmar. It was quiet — eerily quiet — as the research vessel Fulmar motored slowly over open ocean looking for wildlife west of the Farallon Islands, but the five scientists and one educator on the boat were ready for anything. The researchers, concerned about the effect of rising ocean temperatures on the marine ecosystem, had seen everything from breaching whales to frolicking dolphins during nine data-gathering trips last month outside the Golden Gate.

Farallones crew tracks predators, prey in changing ecosystem

By Peter Fimrite SF Chronicle October 6, 2015 Updated: October 5, 2015 8:45am

They had documented a mishmash of skyrocketing humpback populations, record seabird mortality, weird changes in the food web and a profusion of alien species.
Suddenly, a shiny black serpentine figure burst from water, and within seconds the sea was a churning cauldron of activity, with hundreds of sea lions leaping, diving and splashing in every direction around the 67-foot, twin-engine catamaran. “There’s 300, no 400,” Dru Devlin, the marine mammal observer for the Greater Farallones National Marine Sanctuary, yelled as the scientists on the boat jumped off their seats and rushed to the rail, grabbing binoculars and spotting scopes. “There are 500 sea lions out there!”

Documenting trends

The pinniped party, which ended as quickly as it began, was one of many unexplained occurrences during the multiday survey that ended Sept. 27 of the newly enlarged Farallones sanctuary. The project…. is an attempt by researchers, with help from the Cordell Bank National Marine Sanctuary and Point Blue Conservation Science, to document wildlife populations and trends in one of the world’s most abundant marine ecosystems. “This is a project where we look at the oceanographic conditions, the prey availability in the oceans and the predators,” said Danielle Lipski, a research coordinator at the Cordell Bank sanctuary. “We put all these parameters together and get a pretty good picture of the health of the ocean marine ecosystems.” This year’s survey[s] is particularly important, researchers said, because of the incredibly high ocean temperatures caused by a strengthening El Niño weather pattern in the tropics. The water off the Farallones is usually around 53 or 54 degrees during the summer, but temperatures have recently been as high as 63 degrees.

Toll of climate change

The warming ocean is forcing sea life, from microscopic plankton to giant whales, to adapt, migrate or die. The scientists want to document the cascading effect as climate change threatens to make the condition permanent. The skylarking sea lions were among many curious sightings. The crew spotted migrating seabirds, including the black-footed albatross, the northern fulmar, and sooty and pink-footed shearwaters. They saw ocean sunfish and fur seals, but it was the enormous humpback and blue whale migrations that were most confounding. “It was amazing,” said Jaime Jahncke, a marine biologist with Point Blue, formerly the Point Reyes Bird Observatory, recalling a day when at least 100 whales surrounded the boat. “We have had record abundances since 2004 of humpbacks and blue whales.”
It’s hard to explain considering the number of gray whale deaths last spring — the highest one-year death toll in the past 15 years. ….

California sea lions have also suffered. More than 1,300 sick or dying juvenile sea lions have washed ashore this spring and summer, apparently because there are not enough sardines or anchovies in the ocean to sustain them.

Disruption in food chain

Some things can’t be explained, said Kirsten Lindquist, a marine ecologist and manager of the beach watch program for the Greater Farallones sanctuary. For instance, thousands of common murres, a native fish-eating seabird with a large nesting population on the Farallon Islands, have been found dead on beaches along the coast. Lindquist said 480 dead murres were counted just during ocean surveys in August. That’s compared with an August average of 80 dead murres over the past 23 years. Thursday alone, she said, 131 dead murres were seen floating in the water. “We’re in the midst of a common murre die-off,” Lindquist said, noting that murre breeding failures occurred in 1982-83 and 1991-92, both El Niño years, but that the toll was not as bad as this year. “To date, all signs point to starvation from a lack of forage fish,” she said, adding that the same problem has been documented along the Oregon, Washington and Alaska coastlines. “But other species that haven’t been affected eat the same kind of fish. It is abnormal that we’re seeing this all the way to Alaska, so that is something that we’ll be looking into.”
Food is clearly an issue, said Jahncke. The number of krill, the tiny shrimplike crustacean that whales, salmon and seabirds eat, has been fluctuating wildly. There was a similar die-off last year of the Cassin’s auklet, a small gray diving seabird, attributed mainly to a lack of krill, but Linquist said the murre problem seems to be more complicated.

Oceanic transformation

Meanwhile, the anchovy population, which tanked in 2008, hasn’t completely recovered largely because of fluctuating ocean temperatures. Federal scientists also documented a 91 percent decline in sardine numbers along the West Coast since 2007. The Brandt’s cormorant, a black bird with white plumes that can dive as deep as 300 feet for prey, has been reduced by two-thirds since 2007, largely as a result of the disappearance of anchovies, Jahncke said. Global warming may have a lot to do with what appears to be an oceanic transformation off the San Francisco coast, according to the scientists. Besides warm water, spring has been arriving in the area an average of 20 days earlier than it did in 1970, Jahncke said. …..

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