Saturday, October 3, 2015

Galapagos #Penguin Population Doubles With Climate Change


By Brian Stallard
Aug 30, 2015
galapogos penguin
(Photo : Anne Dirkse)

Can climate change be good for penguins?! A new study suggests that at least one unusual species of the swimming birds found on the iconic Galapagos Islands might actually benefit from a changing world.
It's no secret that the great majority of penguins are having a tough time in the wake of climate change. The iconic emperor penguins of Antarctica, for instance, continues to march towards extinction as the average climate of their native habitat continues to warm. Some research has shown that due to shifting ocean currents and water temperatures, these animals are losing the ice from which they fish (not unlike the arctic's polar bears) and often have to move to find new suitable territory.

What's worse, some sub-arctic penguins are being raped and then eaten by local fur seals in a bizarre learned behavior that may be the result of a climate driven decline in the availability of mates or more traditional prey.

seal on penguin
(Photo : W.A. Haddad)
However, for the only known penguin population in the Northern Hemisphere, the shifts in atmospheric winds and ocean current that characterize climate change may actually prove helpful.

Back in 2000, the 19-inch (48cm) black and white penguins of the Galápagos Islands found their way onto an international list of critically endangered species. Thanks to the arrival of invasive plants, new diseases and domesticated animals, the island chain's natives, such as the Galapagos tortoise, have faced rapid decline. It was no different for this unique penguin, and experts speculated that there were only a few hundred of the 'tuxedoed' individuals left on the entire island. Today, it is considered the rarest penguin in the world.

The Hottest Penguin Around

Most of these extremely rare birds can be found on the island chain's westernmost islands, Isabella and Fernandina, where minimum temperatures even in Dec. rest between 70 and 80 degrees Fahrenheit. There, they dive for fish that live in cold pools of water fed by the ocean's chilly and nutrient-rich southwestern current - the very edges of the Equatorial Undercurrent.

"The penguins are the innocent bystanders experiencing feast or famine depending on what the Equatorial Undercurrent is doing from year to year," Kristopher Karnauskas, a climate scientist and researcher, explained in a recent statement.


(Photo : zpics on Flickr)
Karnauskas recently determined that over the past 30 years, changes in wind and ocean currents have nudged the Equatorial Undercurrent further north, bolstering how much cold water reaches the Galapagos' southwestern shores. As a result, the pools the archipelago's penguins rely on to survive have grown larger and packed with plenty of fish.

The researcher and his colleagues at Woods Hole Oceanographic Institution also noted that despite their worryingly small group, the Galapagos penguin population is now growing, swelling to more than 1,000 birds by 2014. The results were published in the journal Geophysical Research Letters.

Swimming in the Face of Extinction

And if you think this current shift was lucky for these birds, you don't even know the half of it. According to Karnauskas' work and others like it, the Galapagos penguins once numbered 2,000 individuals or more. Then in the 1980s a strong El Niño - a time when sea surface temperatures in the tropical Pacific are unusually warm - pushed away essential cold currents. As a result, the penguins starved, dropping to less than 500 birds. Invaders like dogs and cats then disrupted mating and nesting, making it particularly difficult for the population to recover. 

(Photo : zpics on Flickr)
It was the resurgence of the Equatorial Undercurrent that apparently saved these rare birds, but they aren't out of the woods just yet. Northeast of the Galapagos island is a strange and growing patch of warm water called "The Blob" by oceanic experts. Serving as a buffer for cold currents, The Blob has effectively kept nutrient rich waters away from North and Central America's western shores. As a consequence, local food webs are being disrupted, potentially explaining for the starving sea lion pups that are washing up on Californian beaches, and the mass deaths of West Coast seabirds.

According to the NOAA, The Blob is not a consequence of climate change. In fact, the Equatorial Undercurrent's shift may be what's keeping it contained to the eastern edge of the Pacific. Instead, it may be persisting thanks to the emergence of a newly identified El Niño southern oscillation - a purely natural phenomenon that may have helped cause historic drought conditions currently seen in California, Oregon, and Washington.



The Blob continues to press in on the North American coast, as seen last April.
(Photo : NOAA National Climate Data Center) The Blob continues to press in on the North American coast, as seen last April.
What's worse, researchers announced back in Nov. that the pacific is priming for a stretch of particularly harmful El Niños that could threaten both declining coral populations and the Galapagos penguins. The hope then, is that the northern shift of the Equatorial Undercurrent persists, counteracting what could be otherwise disastrous conditions in the Pacific.


According to Karnauskas, that's also why his work is invaluable to conservationists trying to protect the rare penguins. With strong evidence that the regions where the birds feed are expanding (for now), Karnauskas argues that it could be easier to expand marine-protected areas around the islands, giving the penguins a little more growing room.

"With climate change, there are a lot of new and increasing stresses on ecosystems, but biology sometimes surprises us," he said. "There might be places-little outposts-where ecosystems might thrive just by coincidence."

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