How Penguins & Seals Survive Deep Dives

How Penguins & Seals Survive Deep Dives
By Jessica Meir , Scripps Institution of Oceanography (UCSD)

posted: 17 July 2009 08:48 am ET


(1)Juvenile northern elephant seals on the beach at Ano Nuevo. Credit: Jessica Meir, Scripps Institution of Oceanography at UCSD


(2)Jessica Meir scanning for the radio transmission of a seal Jessica Meir scanning for the radio transmission of a seal in our study that has returned from sea (Ano Nuevo Island). Credit: Jessica Meir, Scripps Institution of Oceanography at UCSD
Emperor penguins diving

(3)Emperor penguins diving beneath the dive holes at the Penguin Ranch. Credit: Kathi Ponganis, Scripps Institution of Oceanography at UCSD
emperor penguin colony

(4)Self portrait at the Cape Crozier emperor penguin colony. Credit: Jessica Meir, Scripps Institution of Oceanography at UCSD
























































This Behind the Scenes article was provided to LiveScience in partnership with the National Science Foundation.

My main research interest is physiology in extreme environments, particularly those with low levels of oxygen.

Animals that thrive in such "hypoxic" environments are ideal species to investigate for how their physiology responds. In addition, studying adaptations to hypoxia in animals at high altitude, during hibernation, or in diving environments may provide insight for understanding and treating human medical issues, such as heart attack and stroke.

My recent Ph.D. dissertation focused on the diving physiology of some of the most accomplished diving animals: emperor penguins and elephant seals. Emperor penguins can dive for almost 30 minutes on a single breath, and the record dive of a northern elephant seal is almost two hours!

Both species can dive to great depths — greater than 1,500 feet for the emperor penguin — and almost 5,000 feet (nearly a mile!) for the elephant seal. It is well-documented that animals that can dive well have enhanced oxygen-storage capability in their bodies, a feat accomplished by increased blood volumes and higher levels of the proteins that carry oxygen in the blood and muscle (hemoglobin and myoglobin).

In the lab of my thesis advisor, Paul Ponganis of the Scripps Institution of Oceanography at UC San Diego, we use various approaches to study how these animals manage their oxygen stores to achieve such extraordinary dives.

In the Antarctic, we set up the Penguin Ranch on the sea-ice of McMurdo Sound. During our study, we drilled two dive holes in the ice at our camp site, enabling the emperor penguins to dive freely in the ocean below.

In northern California, we study elephant seals while they are diving at sea. We deploy backpack-style recorders on these animals to document their physiological responses while diving.

Our work, funded by the National Science Foundation (NSF), has revealed extraordinary physiological responses and adaptations that contribute to the diving ability of these animals.

For example, one study revealed that diving emperor penguins have heart rates significantly lower than that of their heart rates at rest. During one emperor penguin’s impressive 18-minute dive, its heart rate decreased to as low as three beats per minute, with a rate of six beats per minute lasting for over five minutes during the dive. As heart rate is a very good indicator of how much oxygen is utilized, decreased heart rates during dives correspond to conservation of oxygen, enabling the animals to dive for a longer time.

To provide a direct look at oxygen depletion, we also measured the levels of oxygen in the blood during the dive using an oxygen electrode. This electrode continuously measured the amount of oxygen in the blood, documenting the rate and extent of oxygen depletion during the dive and providing us with knowledge of how these animals manage their oxygen stores.

Both emperor penguins and elephant seals can tolerate exceptionally low levels of oxygen in their blood, far below the limits of humans and other animals. This assists them in managing oxygen efficiently and contributes to their ability to dive and obtain food. Combined with their enhanced oxygen stores, other physiological responses like reduced heart rates, and factors such as swimming styles and their hydrodynamic body shape, these animals are well adapted to flourish in underwater environments.

Now that I have completed my Ph.D. work with diving animals, I will embark upon studies with another remarkable species: the high-flying bar-headed goose. This bird accomplishes the extraordinary feat of flying directly over the Himalayan mountain range during its semi-annual migration from wintering grounds in India to breeding grounds in Tibet.

Although other migratory birds use alternative, lower altitude routes through mountain passes, flocks of these exceptional high-flying geese have been sighted above the summits of Mt. Everest (29,000 feet) and Annapurna I (26,500 feet). Exercise at these altitudes during the migration may be completed in a single, non-stop flight, with no allowance for acclimatization, flying from near sea level in India to altitudes approaching 9,000 meters in less than one day.

Oxygen levels at this altitude are only about one fifth that at sea level, yet the bar-headed goose increases its oxygen consumption 10- to 20-fold during flight. Birds are generally more tolerant of high altitude than mammals, but sustained flight at these reduced levels of oxygen is certainly exceptional.

The goal of this project is to explore the physiological adaptations in this species, with the overarching purpose of understanding tissue and cellular hypoxia tolerance in an animal that has evolved specifically to maintain performance in hypoxia.

With support of an NSF International Research Fellowship, I will initiate this work in the fall of 2009 in collaboration with researchers at the University of British Columbia in Vancouver, Canada. We will investigate oxygen transport from the respiratory system to the tissue during flight in the bar-headed goose, with specific focus on delivery to the heart.

The next natural question after documenting what these impressive physiological responses are in any of these species, is of course to ask how they are achieved. We will address the mechanisms of hypoxia tolerance in the heart of the bar-headed goose using a variety of physiological, morphological and intracellular approaches.

This work may also provide clues about adaptations in these animals that could benefit humans in the future. For example, tolerance to hypoxia has implications for better methods of harvesting and preserving organs for transplant, and treatment of heart attack and stroke victims.

These animals somehow withstand seriously low levels of oxygen in the blood and tissues that are catastrophic to humans. The issue of reperfusion injury — tissue damage caused by oxygen free radicals when blood flow resumes to an organ which has been deprived of blood — is also relevant. This is applicable to a variety of issues in human medicine, though diving animals appear immune to such concerns.

A complete understanding of the physiology of these organisms is also essential to interpreting their role within ecosystems. Such knowledge has clear ecological and conservation implications and is particularly relevant in the face of global climate change.

Editor's Note: This research was supported by the National Science Foundation (NSF), the federal agency charged with funding basic research and education across all fields of science and engineering. See the Behind the Scenes Archive.

Source:
http://www.livescience.com/animals/090717-bts-extreme-physiology.html

Adelie Penguins Annual Breeding Rituals

Penguin parenting: Adelie penguins reunite for their annual breeding rituals
Animals, July-August, 1997 by Michelle Alten

Near Antarctica's Ross Sea, a bitter wind rips across ice-covered beach. In the blizzard, Adelie penguins hunker 'clown on their nests, covering their newly laid eggs. It is November, and another rigorous breeding season is under way.

Life in Antarctica is a challenge. In the winter, coastal temperatures can drop to minus 22 degrees Fahrenheit; in the summer, they may climb only slightly above freezing. But despite seemingly unbeatable odds, Adelie populations flourish here with a breeding strategy finely tuned to this tempestuous polar region. Adelies are so well adapted to this frigid climate that, while most southern penguins breed in the subantarctic, on outer islands, or on the Antarctic Peninsula, Adelies have colonies all along the Antarctic coast. Emperor penguins also breed in the coldest regions of Antarctica, but Adelies are far more numerous, estimated at 2,465,800 pairs, compared with 195,400 pairs of emperors.

In late October, after a winter on the sea's pack ice, Adelies journey back to their breeding grounds. It is the austral spring, and a frozen sea means Adelies may travel across 60 miles of ice as they return to their colony. First the male arrives, then the female. Each recognizes its mate's call and nesting site from previous years, and perhaps even its partner's physical features. Unless one of the mates fails to return, a pair may reunite for many consecutive breeding seasons.

After a long winter apart, the two penguins thrust their beaks in the air, wave their heads, and let out a raucous call. After this display and renewed bonding, the birds ramble along the barren shore, gathering pebbles in their beaks. Then they strut back to the rookery and place them gingerly around their stone nests.

With the breeding season under way, the penguin colony is alive with activity. At the edge of the rookery, young males, three and four years old, stretch their bills toward the sky and cry out as they stake out their territory and attempt to attract a mate.

The female Adelie penguin lays two eggs. The male, in charge of the first stint of incubation, steps over the eggs and tucks them beneath two protective flaps of skin on his belly. These brood patches keep the eggs secure and warm. The female, free to feed, scampers through the colony down to the beach, pads over a stretch of ice, then disappears into the sea.

For the male, incubation is an endurance test. The father-to-be has not eaten since his arrival, and it may be weeks before his partner returns. This extensive fasting period, which may last as long as 40 days, can cause the penguin to lose a third of his weight.

After a boisterous greeting, the female returning from sea steps behind her partner and scoots into position to take over the job of incubation. Relieved of duty, the male toboggans down a snow-covered hillside and slips off to sea to feed on krill, small shrimplike creatures that are the keystone of Antarctica's complex food chain.

"Adelies capitalize on a huge food source by breeding in the Antarctic," explains Frank Todd, founder of Sea World's Penguin Encounter and author of numerous books on penguins. "They eliminate competition with birds that nest farther north, and even though emperors, which also nest in the Antarctic, include krill in their diet, they also feed extensively on fish and squid."

Penguins must keep careful watch over their eggs. At the rookery's edge, a sheathbill, a white scavenger with a fleshy pink wattle, pushes a penguin egg from its nest. Repeatedly the bird retreats, approaches, and pecks at the shell. Finally it shatters a hole in the egg and begins to eat. Other sheathbills gather for a share, until one flies off with the egg in its beak. Nearby, skuas, black gull-like birds, hover, also hoping to snatch an unguarded egg.

After about 36 days, the faint peeping of a newly hatched chick is heard amid the chatter of adult penguins. The charcoal chick taps at its shell with its egg tooth, gradually poking a way out. After a time, the hungry chick pecks at the parent's bill, begging for food. The adult reaches down, opens its beak, and regurgitates a meal of krill into the tiny, gaping bill.

While the chicks are being reared, pack ice can present a survival challenge, forcing the birds to walk rather than swim to the sea. While Adelies walk about three miles per hour, they can swim almost twice as fast. "The pack ice reduces the frequency that they can feed their chicks," notes David Ainley, an ornithologist and author of The Breeding Biology of the Adelie Penguin. "As a result, chicks can be smaller in weight. This gives them less of a time cushion in which to learn how to catch their own food."

Around the age of four weeks, Adelie chicks leave their parents' protection and gather to form a creche, a group of up to 100 or more youngsters. The chicks huddle together for warmth and for defense against skuas. Now both parents feed at sea, nourishing themselves and gathering food for their growing youngster.

Gradually the chicks lose their fuzzy down and gain their mature black and white feathers. After 56 days, many leave the creche behind. Now larger in size, they return to their nests, no longer fearing the assaults of skuas.

A cluster of adults forms at the water's edge. A few penguins peer over the ice. No leopard seals. One bird pauses, then dives into the icy ocean. The next one follows, then the next. Finally all the penguins tumble into the sea, like a chain of dominoes. In the water, penguins take no chances with leopard seals, which are ferocious predators. A seal will grab hold of a penguin, whip it inside out, removing its skin, and swallow it whole.

In Antarctica the Adelies face constant hazards. During the austral summer, storms with savage gales and freezing temperatures often rush in without warning. A layer of blubber and tightly packed feathers help adults withstand the cold. Young chicks are often not as lucky. If they are not sheltered by a parent or the creche, they may freeze or be buried in snow.

By February many Adelie juveniles have made it through the breeding season and are ready to fledge. Despite the rigors of Antarctic life, studies in the Ross Sea have shown that about 75 to 85 percent of chicks that hatch usually survive to the fledgling stage.

"The number of Adelie penguins has been increasing in the high-latitude areas of the Ross Sea," Ainley points out. "The changes may be due to decreases in the amount of pack ice, caused by global warming."

Meanwhile, at the close of each breeding season winter steals in, covering the continent with darkness. Antarctica's "ice birds" leave behind their colonies and head out on the frozen sea.
Bibliography for: "Penguin parenting: Adelie penguins reunite for their annual breeding rituals"

Michelle Alten "Penguin parenting: Adelie penguins reunite for their annual breeding rituals". Animals. FindArticles.com. 16 Jul, 2009. http://findarticles.com/p/articles/mi_m0FRO/is_n4_v130/ai_19634761/

Source:
http://findarticles.com/p/articles/mi_m0FRO/is_n4_v130/ai_19634761/?tag=content;col1
Image: Flickr Uploaded on January 28, 2007 by mark van de wouw

For Darren... :)

New Message from Dr. Dee Boersma

Hello Penguin Fans,

The 2009 Spring update is here! Learn how the 2008-09 season went and what is new at the Penguin Project. The 2009 Spring Newsletter text can be found below or I have attached the newsletter with pictures as a pdf. We also recently renovated our website (www.penguinstudies.org) to include up-to-date penguin news from around the world as well as anything and everything Magellanic Penguin. You can find all of our newsletters, including this most recent one, on the website under 'Publications'. Additionally, Turbo is now on Facebook so make sure to search for 'Turbo the Penguin' and add yourself as a fan to see exciting pictures, videos and stories all about Turbo!

Dee

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Spring 2009 Penguin Update
by Dee Boersma

Five consecutive years of successful chick rearing is in many ways a hopeful sign. Despite a storm that likely killed 16% of the chicks, adults raised 3/4 of a chick per nest, which is well above the 25 year average of a 1/2 chick per nest (most pairs don't raise any chicks). In the areas we call the Canada and Sea we checked 181 nests and 32 pairs fledged both chicks. But in spite of another successful year, the number of active nests in the colony is down 23.1% from 1987. Winters still are tough on the penguins. Only about 2 to 5% of the penguins on the beach this year were juveniles, so few chicks from last year apparently survived. Getting penguins to breed at Punta Tombo requires that they survive several winters, but last winter many juveniles swam to northern Brazil where they eventually starved. Penguins also encountered an oil spill in their winter grounds. There are several dozen groups dedicated to rehabilitation of penguins in northern Argentina, Uruguay and south Brazil, so we need your help to turn our attention to solving this problem. Penguins with petroleum in Chubut are nearly as rare as hen's teeth. We saw one penguin with some petroleum at Punta Tombo, but that was it. Moving the shipping lanes in 1994 and a decrease in illegal dumping of ballast water has helped the penguins. In March, when Esteban Freres and I walked 25 km of beach along the Chubut coast, we found no penguins either dead or alive with petroleum. Penguins are still getting oiled in the north (northern Argentina, Uruguay and southern Brazil), however.

For the second year in a row, we found featherless or ‘naked’ chicks at Punta Tombo. The chicks hatched with an initial layer of down but failed to grow in their second layer of down. They then remained ‘naked’, resembling plucked chickens, until they grew in their juvenile plumage when they were approximately one month old. We speculate that a virus may be the culprit, and our newest graduate student, Olivia Kane, will be investigating this problem.

We deployed 27 satellite tags at Punta Tombo and 10 at Cabo dos Bahìas this season. Penguins are traveling farther to find their food since we began satellite tracking 12 years ago. This year, they swam a mean distance of 430 km from Punta Tombo during incubation, nearly the same as in 2007 (431 km), but approximately 40 km farther than in 2006 (394 km), and almost 100 km farther than the distances traveled prior to 2001.

We had several unexpected and amazing visitors this year. A young man from Ireland, Keith Norris, who suffers from cystic fibrosis, and whose wish was to see penguins in the wild visited thanks to the Make-A-Wish Foundation. We taught him how to measure the volume of a (plastic) egg, and showed him the weigh scale, and walked with him through the penguin colony to give him a sense of how we keep track of all the penguins. In November and again on December 25th, the cormorant colony at the tip of the point had a visitor from southern Africa, a Cape Gannet (Morus capensis). Cape Gannets are rarely seen in Argentine waters. This is the second year we saw a Cape Gannet at Punta Tombo, and it's likely the same one from last year.

Our third visitor, a King Penguin, arrived for a day in December. The beautiful giant preened and made contact calls while resting on the beach. When no King penguins answered he left, but seeing him was a pleasant surprise for everyone except the Magellanic penguins, which seemed to think he was weird.

In 2007, we implanted radio identification tags (similar to those implanted into dogs and cats by veterinarians) in approximately 150 birds, and put out two reading pads that recorded tag numbers, time of day, and direction of travel when penguins cross them. This year we put out a scale to weigh penguins as they walked over it. We got over 10,000 readings and are in the process seeing if we can translate those light and heavy footsteps into weights. We are designing a system to tell use who, when and what direction a penguins was going and its weight. If and when our system works, we can determine the effect of opening and closing of the fisheries on adult penguin fishing success and chick growth. The penguins continue to be a challenge as they pull out cords and walk around the pads, and some only put one foot on the scale. The penguins and technology are a constant challenge, but we hope to win the battle and get accurate and reliable data this coming season.

On April 4, 2009 we celebrated the 25th Anniversary of the Penguin Project by unveiling the U of WA Center for Penguins as Ocean Sentinels. The Penguin Project, The International Penguin Society, Conservation magazine, and volunteer student research and education programs are the four pillars of the Center. The Penguin Project will continue to follow individual penguins, monitor the colony and develop the data needed to plan effective conservation efforts. The International Penguin Society, launched with a Pew Fellowship to Dr. Pablo Borboroglu, an Argentine conservationist, will develop and advocate solutions for sustainable marine activities and management, drawing on penguins as a charismatic, keystone species. Conservation magazine, started in 2001, is the voice for the science behind conservation. The magazine’s mission is to raise the bar on environmental thinking and writing. The Center is dedicated to educating the next generation of conservation leaders. We believe the new University Center will increase our ability to make a positive contribution to the lives of penguins, people, and conservation. As always we are honored by and welcome your support. These are challenging times and it is your support that makes it possible to continue our satellite work: $5,000 allows you to name a penguin that we will follow closely and provide you with maps and its life story each year.

Best wishes,
Dee

P.S. If you would like to accompany me and other wildlife enthusiasts on the trip of a lifetime. there is still room on the University of Washington expedition to the Galápagos (October 31 through November 8, 2009) . If you are interested please contact Olivia Kane at oliviaj@u.washington.edu.

Penguin Parents Won’t Chip In to Help Handicapped Spouse

Penguin Parents Won’t Chip In to Help Handicapped Spouse

* By Hadley Leggett Email Author
* July 2, 2009 |

Tired of your partner not helping out with the kids after you’ve had a tough day at work? At least you’re not a handicapped penguin parent trying to fish with a Plexiglas box strapped to your back.

Penguin pairs are known for their elaborate collaboration in raising chicks under harsh Antarctic conditions. But it turns out penguins will take teamwork only so far. When French scientists handicapped one bird from each of 46 pairs of Adélie penguins, partners of the unlucky birds didn’t step up to help out their mates, or to provide extra food for their chicks.

“In Adélie penguins, when one mate was handicapped, no compensatory care was observed from the partner,” researchers from the Institut Pluridisciplinaire Hubert Curien reported Tuesday in Animal Behaviour. “As a consequence, handicapped individuals and offspring both supported the whole additional breeding cost of the handicap.”

box1After a female penguin lays one or two eggs, she leaves the nest to forage for food while dad guards the eggs. Once the chicks hatch, mom and dad share equal responsibility for baby-rearing, with one parent enduring long periods of fasting to care for chicks while the other parent hunts at sea.

To study the effects of a handicap on pair cooperation, the researchers chose one unlucky bird from each penguin pair and attached a small Plexiglas box to its middle-back feathers. Similar to the first-generation tracking devices used by penguin researchers in the 1990s, the boxes were designed to increase underwater drag during diving and fishing, but not to interfere with the penguins’ other activities.

“According to previous studies, we could guess what the potential effects of the dummy devices would be on handicapped penguins, but not on their partner or their chicks,” animal ecologist Michael Beaulieu, a co-author on the study, wrote in an e-mail.

As expected, the handicapped penguins spent more time hunting at sea and came back with less food for their chicks. But instead of helping out, partners of the handicapped birds essentially ignored the plight of their unlucky mates. Partner penguins didn’t compensate by spending more time foraging for food or bringing back extra fish. And at the end of the study, while both handicapped birds and their chicks weighed less than their unhindered counterparts, the handicap-free partners stayed fat and happy.

It’s tempting to blame penguin partners for their negligence and insensitivity, especially because similar handicap studies in other species have shown that some birds, including passerines and great tits, do compensate for their mate’s deficiencies.

But Beaulieu has a different explanation: Because penguins are long-lived birds, it doesn’t make evolutionary sense for them to invest too much effort in any single reproductive season.

“Short-lived birds have only a few breeding attempts during their lifetime while long-lived birds have a lot,” he said. “As a result, short-lived birds are expected to give the maximum during one breeding season to increase the probability of survival of their current chicks.” Long-lived birds, on the other hand, should prioritize their own long-term survival over the outcome of individual chicks.

“Consequently, when the investment of the partner decreases,” Beaulieu said, “short-lived birds are expected to compensate while long-lived birds are expected to keep a fixed level of parental investment.”

The evolutionary explanation makes sense, but there’s one other possible explanation: It appears that male penguins don’t have great communication skills. Handicapped dads didn’t convey their distress to females after returning from a hunt, and when mom came back squawking about her feeding troubles, dad didn’t listen.

“If you do not ask for help, I will not help you,” Beaulieu said. “That may also explain why they did not compensate.”

Source:
http://www.wired.com/wiredscience/2009/07/penguinpartners/

Scientists find extinct penguin

Scientists find extinct penguin


RAY LILLEY

WELLINGTON — The Associated Press Last updated on Tuesday, Mar. 31, 2009 09:13PM EDT

Researchers studying a rare and endangered species of penguin in New Zealand have uncovered a previously unknown species that disappeared about 500 years ago.

The research suggests that the first humans in New Zealand hunted the newly found waitaha penguin to extinction by 1500, about 250 years after their arrival on the islands. But the loss of the Waitaha allowed another kind of penguin to thrive – the yellow-eyed species, which that now also faces extinction, Philip Seddon of Otago University, a co-author of the study, said Wednesday.

The team was testing DNA from the bones of prehistoric modern yellow-eyed penguins for genetic changes associated with human settlement when it found some bones that were older and had different DNA.

Tests on the older bones “lead us to describe a new penguin species that became extinct only a few hundred years ago,” the team reported in a paper in the biological research journal Proceedings of the Royal Society B: Biological Sciences.

Polynesian settlers reached New Zealand around 1250 and are known to have hunted species such as the large, flightless moa to extinction.

Dr. Seddon said dating techniques used on bones pulled from old Maori trash pits revealed a gap in time between the disappearance of the Waitaha and the arrival of the yellow-eyed penguin.

The gap indicates the extinction of the older bird created the opportunity for the newer to colonize New Zealand's main islands about 500 years ago, said Sanne Boessenkool, an Otago University doctoral student who led the team of researchers, including some from Australia's Adelaide University and New Zealand's Canterbury Museum.

Competition between the two penguin species may have previously prevented the yellow-eyed penguin from expanding north, the researchers noted.

David Penny of New Zealand's Massey University, who was not involved in the research, said the waitaha was an example of another native species that was unable to adapt to a human presence.

“In addition, it is vitally important to know how species, such as the yellow-eyed penguin, are able to respond to new opportunities,” he said. “It is becoming apparent that some species can respond to things like climate change, and others cannot. The more we know, the more we can help.”

The yellow-eyed penguin is considered one of the world's rarest. An estimated population of 7,000 in New Zealand is the focus of an extensive conservation effort.

Source:
http://www.theglobeandmail.com/news/technology/science/scientists-find-extinct-penguin/article722991/