Saturday, March 21, 2015

From sea lions to #penguin chicks, adorable animals are dying in droves

We know and love sea lions for their soulful eyes and playful antics — they’re basically the golden retrievers of the ocean. But recently, sea lions have been making headlines for much sadder reasons: Droves of malnourished sea lion pups have been washing up all over the Southern Californian coast. More than 1,450 pups have stranded without their mothers since January, reported the Washington Post.

The cause? Starvation.

Warmer waters off the coast of California are likely driving away sea lions’ prey such as squid, anchovies, and sardines, said Justin Viezbicke, stranding services coordinator for the National Oceanic and Atmospheric Administration (NOAA). As a result, mother sea lions are having to go further from birthing grounds — usually around the Channel Islands — to forage for food, meaning that pups probably don’t get enough nutrients from their mothers when they return. The pups then wean off their mothers earlier and are underweight when they leave the island, likely to find food of their own.

“They’re leaving with a low tank of gas and there’s really not much out there to help them out,” said Viezbicke. “They’re jumping into … a challenging environment and then they’re ending up washing ashore on the mainland, starving.”

Organizations like NOAA and other animal rescue programs have been taking in pups and feeding them — but that’s only a stopgap measure.

“This is something that’s naturally occurring out there, so there’s really not much we can do other than watch and learn from the situation,” Viezbicke said. “We can’t really prevent or stop it, unfortunately.”

Left to their own devices, these stranded sea lion pups probably wouldn’t make it. (No judgement if you need a tissue here. I’ll wait.)
Fred Hochstaedter
As sad as it sounds, starvation events and mass mortality events (in which vast numbers of animals die), are becoming more and more common in this wacky, warming world. Thanks to a number of large-scale, systemic alterations (lookin’ at you, El Niño and warming ocean temps), the world’s ecosystems hang in a delicate balance.

Meet the Cassin auklet — a pudgy, fist-sized seabird with crescent-shaped eye markings and pale blue feet. They’re pretty dang cute. And thousands of them are washing up dead along the West Coast — all the way from Northern California to British Columbia.

“My volunteers alone … have found 7,000 carcasses [over the last four months],” said Julia Parrish, executive director of the Coastal Observation and Seabird Survey Team (COASST) at the University of Washington. “It’s a scary big number.”

Like the sea lions, auklets are literally dying for a meal. The birds primarily feed on zooplankton or krill. However, in the last year, a mass of warm water — very scientifically named “the blob” — drove the usual Pacific krill into deeper waters and brought in a host of zooplankton that the auklets don’t eat, reported Audubon Magazine.

When a high number of birds wash ashore dead, the events are called “wrecks.” Generally speaking, smaller wrecks are fairly normal, Parrish explained. If there’s a storm out at sea, it’s not unusual for seabirds caught in its path to die, whether from starvation or storm conditions, and later wash up on beaches. That’s just how it goes.

But this time, something is different. “This is the biggest wreck we’ve ever seen in the 16 years we’ve been doing this work,” Parrish said. “I think it’s probably the largest wreck we’ve seen on West Coast … That makes me sit up and take notice.”

This winter’s wreck could be especially bad if enough of the dead auklets turn out to be adults, because an entire reproductive group may have been wiped out. They won’t know for sure until the birds return to their breeding grounds. Until then, it’s a lot of waiting and counting dead birds.
D. Derickson/COASST
So is this climate change at play? Scientists are hesitant to say.

Dee Boersma, a conservation scientist and founder of the Penguin Sentinels Project at UW, compares the vulnerability of seabirds to weather and climate to the vulnerability of a human crossing a busy street: You could get hit by a truck, but it doesn’t happen every time. And just as it’s hard to predict exactly how likely you are to survive a street-crossing as a human, the same goes for storms and their effects on Magellanic penguins, she said.

In 2014, Boersma and other penguin researchers published a study in PLOS ONE which found that climate change was directly responsible for the deaths of more than 200 Magellanic penguin chicks from 1983 to 2010 in Punta Tombo, Argentina. There, climate change is increasing the intensity and frequency of storms, while lowering the reproductive success of Magellanic penguins, the study reported.

During the 27-year-long study, young penguins perished at a high rate due to a combination of starvation and overexposure during exceptionally rainy and hot seasons. The chicks’ feather coats keep them cozy when they are dry, but that changes when they get wet: The fluffy down isn’t waterproof, like adult penguin feathers. So if a penguin chick gets caught in the rain during a storm, it’s like a human “being stuck outside and naked in a wet sleeping bag … the penguins basically die of hypothermia like you or I would,” said Boersma.

Plus, a lack of food leaves the chicks unprepared to cool themselves down when things heat up, since they rely on the food their parents bring them for all of their water. Without adequate hydration, the chicks can’t depend on evaporation to keep cool and become vulnerable to heat stress.

It’s a lethal combination: Over the course of the study, an average of 65 percent of the Punta Tombo chicks died every year, with about 40 percent dying of starvation.
Chicks that died of hypothermia after a rainstorm.
Chicks that died of hypothermia after a rainstorm.
Dee Boersma / University of Washington
So what was that about climate change again? Mass animal die-offs and starvation epidemics are shocking no matter what, even to hardened scientists. Climate change is just exacerbating these kinds of things.

“The fact is that we have populations responding to warming events, whether the warming is temporary or inexorable,” said Parrish, the researcher studying the dying auks.

The world’s ecosystems are hanging on as best they can, but small things can throw them out of balance. It’s unfair to compare the temperatures that a wild ecosystem can withstand to the temperatures humans can, because we have tools and technology on our side. “Wildlife needs habitat,” Parrish said. “In today’s crowded world, habitat only exists in certain places — places that we protect. And when the climate warms, those places change.”

“[Even one degree] is a huge deal,” Parrish points out. To understand and support conservation efforts, humans need to “think like a fish, a clam, or an oyster, and not like a person.”

Guess it’s time to get in touch with your inner oyster or auklet — getting hungry yet?


Tuesday, March 17, 2015

Penguin waddle put to the test

A penguin's waddle is one of nature's weirdest walks
"Come on Puddle… You can do it!" yells Prof John Hutchinson.
Puddle - a Humboldt penguin - seems more than a little bemused.
And with good reason.

A team of scientists have come to Penguin Beach at London Zoo, installed a hi-tech track and are now trying to lure Puddle and his penguin pals across it.
"Go Puddle, go!" encourages Prof Hutchinson, from the Royal Veterinary College (RVC).
And at last - with a fishy treat to help him along the way - the little bird waddles along the runway.
It is this distinctive walk that scientists from RVC and University of Texas at Austin are here to study.
Beneath the track lie force plates loaded with sensors, which allow the researchers to analyse how these birds get around.

"Penguins move in a really weird way," explains Prof Hutchinson.
"They have a very upright posture like a human, but they also have very short, crouched legs - it is very comical."Prof John Hutchinson on the eccentricity of the penguin's walk
He adds: "But when I see an animal do something weird, as an evolutionary biologist, I want to know how that evolved, how it got that way.
"And with these experiments, we're trying to tie what we know about penguin evolution with penguin physics."

Foot swing

Previous studies of the penguin's ungainly gait have revealed that the waddle is in fact the most energy efficient way for them to get about on land.
But these experiments will reveal exactly how they are doing this.
"They are applying forces left and right as they swing their bodies from side to side," says Prof Hutchinson.
"But what is not known about penguins is how the legs do that, how big are the sideways forces on penguin legs and how that compares to other waddling birds.
"And that's why we need these force platforms to measure the forces in the legs individually."
The Waimanu is one of the oldest penguins discovered - and most likely had a more horizontal posture
But it turns out that penguins didn't always waddle. Fossils reveal that their ancient ancestors moved in a different way.
"We have all kinds of fossils as far back as 60 million years ago from the Southern Hemisphere," says palaeobiologist James Proffitt, who has come from Texas to study the birds.

"That gives us a chance to understand how these unusual anatomies and behaviours have evolved in deep time and how we have all these bizarre things we see today."
The bird bones show that the first penguins were a varied bunch: some were tiny, but others grew as tall as humans, hunting large fish with their spear-like beaks.
James Proffitt is particularly interested in a genus of penguins known as Waimanu.
These birds, unearthed in New Zealand, are the oldest-known penguins, living between 58-60 million years ago.

Mr Proffitt explains: "We know that penguins such as Waimanu were also flightless, wing-propelled divers based on things like their wing proportions and their relative size.
"But in many ways they were different, and they probably moved about differently on land based on the anatomy of their legs and hip bones."
The team believes that these proto-penguins had a more horizontal posture, and their walk would have looked similar to that of a modern-day albatross.

Today's penguins most likely evolved their unusual anatomy and resulting waddle as they became better and better adapted to swimming.
As their body shape changed to help them fly through the water with ease, they became more and more clumsy on land.

Penguin Penguins use their wings to fly through the water

Back at the running track, and the penguins seem to be enjoying not quite doing what they are told.
But Zuzana Matyasova, London Zoo's deputy team leader for the bird department, has found a way to attract their attention.

A combination of some dangling string, a tennis ball on a stick - or some fish - is proving hard for some penguins to resist.
"Some of the youngsters are really inquisitive: anything new in their enclosure is almost like a challenge and they want to be the first ones to try it out," she explains.
She's hoping all this hard work will shed light on these birds.
"I work with them every day, and I wonder about their way of moving - their distinctive waddle is just amazing."

While not every bird fancies taking a waddle down the runway, after several days, the scientists manage to collect enough data to begin their analysis.
And by comparing this with their studies of ancient penguins, they hope to establish how and when one of nature's most distinctive walks evolved.


Thursday, March 5, 2015

#Penguins Rapidly Conquered New Zealand After Humans Ate Rivals

by Becky Oskin, Senior Writer   |   March 03, 2015

Sunday, March 1, 2015

Genetics reveal Antarctica was once too cold for #penguins

Emperor penguins are adapted to the bitter cold of Antarctica, but a new study reveals that during the last ice age it got too cold even for them.
Not too hot, not too cold, but just right. Gary Miller/Australian Antarctic Division, Author provided
Emperor penguins are truly remarkable birds – they thrive in the coldest environment on Earth and live year-round on the ice. Breeding colonies congregate on sea ice during the Antarctic winter and must withstand temperatures that regularly drop below -30C.

In fact, emperor penguins are so adapted to cold conditions that they become heat stressed when temperatures climb above 0C. Emperor penguins are therefore particularly threatened by climate change, and their numbers are expected to decline in the coming decades.

However a new study, published today in Global Change Biology, shows that it was once too cold even for emperor penguins.

Penguins past and present

In our study of how changing climate has affected emperor penguins over the past 30,000 years we found that, during the last ice age, emperor penguins were roughly seven times less common than today. What’s more, it appears that only three populations survived the last ice age. The Ross Sea was a refuge for one of these populations.

In the first continental-scale genetic study of emperor penguins, we examined genetic diversity of penguins modern and ancient to find out how they’re related. We collected genetic samples from eight breeding colonies – no easy feat given that emperor penguins live in some of the remotest places on Earth in conditions that would send most people running for a roaring fire and a hot cup of tea.
A rookery near Mawson station. Chris Wilson/Australian Antarctic Division, Author provided
Reaching the colonies involved weeks on the notoriously wild Southern Ocean (and considerable seasickness), helicopter journeys over pristine expanses of sea ice, and long snow shoe and ski traverses. The “A” (for Antarctic) factor was a constant presence, with delays caused by heavy sea ice that trapped ships for days at a time and blizzards that grounded helicopters.

Nevertheless, the effort paid off. Analyses of genetic data allowed us to reconstruct the population history of penguins, and correlate it with environmental conditions inferred from ice core data. The findings indicate that approximately 12,000 years ago, after the ice age ended and temperatures began to rise and sea ice around Antarctica decreased, emperor penguin numbers began to climb.

Goldilocks penguins

The emperor penguin’s relationship with sea ice can be described as a Goldilocks phenomenon.
The penguins need stable sea ice to stand on during their breeding season. If the sea ice extent is too great then the journey between the colony and their feeding grounds in the ocean may prove too costly in terms of energy reserves.

If there is too little sea ice or if the sea ice is not stable enough, then the penguins cannot establish successful breeding colonies. The duration of the sea ice season is also important – if the season is too short for the chicks to adequately mature, then they may not have time to grow their adult, waterproof feathers and will not survive at sea.
Some like it hot… but not emperor penguins. Frederique Olivier/Australian Antarctic Division, Author provided
During the last ice age there was about twice as much ice as there is today. Emperor penguins were probably unable to breed in more than a few locations around Antarctica. The distances from the open ocean, where the penguins feed, to the stable sea ice where they breed was probably too great in most of their modern breeding locations.

The three populations that did manage to survive the ice age may have done so by breeding near polynyas – areas of ocean that are kept free of sea ice by wind and currents. One of the most important of these polynyas was located in the Ross Sea.

Uncertain future

Because of this Goldilocks relationship emperor penguins are facing an uncertain future. Antarctic sea ice extent has been measured using satellites for the past 35 years. In this time, large changes with very different trends in different regions have been observed.

For the past three years in a row winter sea ice has broken records for total maximum extent. This overall increasing trend masks major regional changes in the extent of the sea ice field and the duration of the sea ice season.
Emperor penguin colonies are found right around the Antarctic continent. Jane Younger, Author provided

In some areas, such as the Bellingshausen Sea, there has been a large decline in sea ice while in others, including the Ross Sea, sea ice is increasing. These fluctuations in sea ice are likely placing a huge strain on emperor penguin populations, which is set to continue into the future. As areas suitable for emperor penguin breeding become scarcer it is becoming increasingly important to conserve areas known to support penguin populations.

It’s clear that the Ross Sea was a critical area for emperor penguins in the past and this suggests it will provide an important refuge for breeding colonies in the future. This emphasises the need for careful protection of this vital part of the Antarctic ecosystem.

A marine protected area, to protect roughly 1.34 million square kilometres of the Ross Sea from commercial fishing, was proposed by New Zealand and the United States at the last meeting of the Commission for the Conservation of Antarctic Marine Living Resources in October 2014. The proposal was rejected, but a Ross Sea marine park is likely to be on the agenda again at the 2015 meeting.

Emperor penguins are remarkably hardy birds, surviving in one of the harshest environments on earth. However their reliance on a narrow range of suitable habitat highlights their fragility, and raises concern over their future in a world undergoing its most rapid environmental change in history.

What does the future hold for Emperor penguins? Gary Dowse/Australian Antarctic Division, Author provided