Wednesday, 7 August 2013

NHL Animal Week - Pittsburgh

The NHL has a few teams with logos that feature animals, so it became apparent that with Shark Week on Discovery Channel that I should feature an NHL Animal Week where some real biology can be discussed! There are seven teams that distinctively could be featured, and we've taken a look at the animals in the logos of the San Jose Sharks, Florida Panthers, and the Boston Bruins in the previous days. Today, we focus on a bird that is exclusively found in the southern hemisphere as we look at the penguin from Pittsburgh's logo on HBIC's NHL Animal Week!

Wednesday - Pittsburgh Penguins

While the stylized cartoon penguin that occupies the logo of most Penguins jerseys is rather generic, there was one jersey that saw the Penguins narrow the focus onto one species of penguin that would be representative of the team. The emperor penguin, with its identifiable yellow feathers, would be the penguin represented in that old Penguins logo, and that bird will be the species we focus on as we continue our look at animals in NHL logos. There are twenty-two penguin species that exist exclusively in the southern hemispehere, ranging from near the equator as far south as Antarctica. They all belong to the family taxonomy Spheniscidae which contains six genuses.

The emperor penguin, Aptenodytes forsteri, is the largest penguin species in the world. The emperor and king penguins are the only living species of Genus Aptenodytes. These two penguin species are also found furthest south, and closely resemble what archaeologists believe larger, extinct penguins would have been. The emperor penguin is found exclusively on Antarctica and the surrounding islands. Emperor penguins weigh in between 40 to 100 pounds and stand at around 45 inches tall, and their total population is estimated to be close to 300,000 individuals.

One of the key features of Aptenodytes forsteri is their reproduction. The male and female are serially monogamous from year to year, but fidelity rate drops to approximately 15% when looking at year-after-year mates. A clutch of one egg is the standard as emperor penguins nestle the egg beneath their fat on top of their feet for warmth. Nests of stones are not made, making them different from other penguins in this respect as well. Sexual maturity occurs around the bird's fourth year, and the penguins may find new mates year after year depending on circumstances.

Emperor penguins also have an extremely complicated reproductive process. Mating season occurs between September and November with eggs being laid in March or April during the winter, and mating season is triggered by the shorter winter days. This has been reproduced in zoo settings to aid in the mating ritual. Both sexes care for the egg which weighs approximately one pound. Up to 20% of that weight is the weight of the shell as the egg needs to stay protected in the harsh Antarctic environment. After laying the egg, the mother is normally depleted of fat reserves, so a transfer from her feet to the male's feet occurs. This can be difficult, and, if the egg hits the ice, there's a good chance that the chick inside will be lost due to the frigid environment. If the transfer is successful, the male will use his body heat to keep the egg warm for over two months until the chick hatches. During this time, the female has been off feeding, replenishing the lost weight and fat reserves it needs. She returns around the hatching time to take over the feeding of the chick. If the egg hatches before she returns, the male will feed it through regurgitated protein and fats produced by a gland in his esophagus. With the female taking over the feeding process, the male leaves for up to one month to replenish himself. Once he returns, they alternate within days of one another, feeding and caring for the chick.

Once old enough, chicks leave the protective cover of their parents and form their own group called a crèche where they huddle together for warmth as they learn how to live in Antarctica's harsh climate. In early November, the molting process starts, and the entire crèche heads towards the sea where they will feed at sea.

Penguins have some impressive speed through the water despite their rotund shape. Emperor penguins reach speeds up to 10 mph or 15 kmh in the water. They streamline their shape by hunching their heads into their shoulders. Their feet are pulled in tight against their bodies to aid in steering while "flying" through the water. Penguins have much denser breast and wing muscles to aid in their propulsion as they paddle with their modified wings. Penguins also have solid, dense bones to help them be less bouyant than their avian counterparts, allowing them to dive with ease. While some penguins "porpoise" - jumping out of the water before submerging again - to aid in moving through the water while breathing, emperor penguins prefer underwater travel, surfacing only to breathe. Genus Aptenodytes seems to be the only penguin genus not to "porpoise", and this is believed to be due to their size and weight. They will, however, use floating ice floes to rest on while hunting for fish in the ocean. Penguins alos have glands under the eyes that help rid the body of excess salt. Penguins must drink water to survive, and take in sea water as their main supply of water. The gland under the eye helps to secrete this massive amount of salt taken in by the penguin. This secretion often collects as droplets on the bill and are shaken off.

Most dives of the emperor penguin last between two to eight minutes, and rarely do they go to great depths as their prey frequent the warmer waters near the surface. The maximum recorded depth for a emperor penguin dive was 535 meters or 1755 feet! To aid in their time below the surface of the water, penguins hyperventilate at the surface before inhaling and diving. Heart rates slow while diving as the penguins conserve oxygen, and some penguins exhibit reduced peripheral blood flow to maintain a steady core temperature. The heart rate of a emperor penguin in a dive is about 60bpm, much lower than its resting heart rate of about 72 bpm.

Their exterior feathers overlap to create a nearly windproof and waterproof exterior layer that covers the warm downy feathers below. Their darker feathers help to warm the penguins in the sunlight, and preeening rearranges their feathers to help trap an insulating layer of air under their feathers. They also have a solid layer of fat to help insulate them when in the cold water, and movement while in the water warms muscles and keep the penguins warm as well. Emperor penguins have a unique heat exchange system in their nasal passages which helps them recapture heat from their exhaled breath as well! On land, emperor penguins lean backwards on their heels and tail, raising their toes off the cold ground to prevent frostbite and/or freezing. In short, the penguins of the Genus Aptenodytes are well-suited for a cold, icy environment through many adaptations.

The diet of the emperor penguin includes fish, medium-sized squid, krill, and crustaceans. Antarctic silverfish make up the majority of the emperor penguin's diet. Currently, the food chain for the emperor penguin is not at threat by fishermen, so there is no reason to believe that the population of the king penguin will decrease in the coming decades.

There are several species that prey upon king penguins depending on where they are in their life cycles. Skua, a marine bird, will take unguarded eggs and young chicks when given the opportunity. The southern giant petrel, another marine bird, will scavenge off dead penguins, but are responsible for about one-third oo penguin chick deaths in some colonies. Leopard seals hunt penguins, and orcas have also been sighted feeding on penguins. Leopard seals commonly attack in the water where the seals are generally much faster that the penguins. Man has yet to pose a threat to the emperor penguin in terms of killing birds thanks to the harsh environment where the penguins live and breed. Thus far, man has had little impact, but the penguins will defend their colonies if a tourist mistakenly wanders into a colony.

At this time, there is no threat to the emperor penguin in terms of being watched by CITES. Their numbers are decreasing thanks to the ice floes melting as a result of global woarming, but their numbers are still strong enough that scientists are observing them only.

There is an overview into the world of the emperor penguin, the animal on which the Pittsburgh Penguins based their logo. Clearly, they are a fascinating animal in terms of their biological make-up, and have adapted to their harsh environment very well. Tomorrow, we'll break as The Hockey Show preview will be posted, but we'll be back on Friday with the Phoenix Coyotes!

Until then keep your sticks on the ice!

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