All Dressed Up for a Fish Dinner

October 1, 2018
Biology

Penguins are fun birds to watch, but at the same time, they are different from other birds, mainly because they do not fly. At Ripley’s Aquarium of the Smokies in Gatlinburg, Tennessee, I was able to watch them up close and learn more about them from Megan Close, Senior Aviculturist. Megan is living her childhood dream of working with African penguins, and she has a double degree in Psychology and Biology together which helps her to understand the penguins better.

As mentioned, penguins are different from flight birds. One of these physical differences is that penguins have solid bones as opposed to flighted birds who have hollow, honeycomb bones. Megan says the solid bones allow them to sink in water, whereas, if their bones were hollow, it would be like humans having a life jacket on in water. Penguins also have 70 feathers per square inch of their body as opposed to flighted birds who have only 7-10 feathers per square inch. As a defense against the cold, all penguins wear a double duty suit. The outer layer is made up of short, rigid feathers with flattened shafts and slightly bent tips. When lying flat, this pattern resembles that of roof shingles on a house. The exposed tips overlap to form a surface that is practically impervious to wind and water. Beneath the hard coat, the feathers have soft, downy filoplumes that act as a layer of insulation like long underwear for humans.

Penguins normally weigh 5-7 pounds, have a hook built into their beak for grabbing fish and swallowing them down, barbs that help guide their  food down to their stomach without chewing, and they have heat vents in the areas above their eyes and on their feet where there are no feathers. Penguins have the ability to stay under water for as long as 5-7 minutes for the African Penguins, and as long as 20-30 minutes for the Emperor penguins. Megan says there are 17 species of penguins (some say 18), but there are only 2 species that stay in snow and ice year round - most are warm weather penguins. All penguins fish in cold weather, however, and live in the wild south of the equator.

The African penguins are a good fit for Ripley’s Aquarium of the Smokies in Gatlinburg, Tennessee. They can live in weather from 30°F to 100°F, however, like humans, they prefer the temperature to be between 50°F and 80°F.  As I watched Megan and her assistant feeding the penguins, I noticed some of the penguins were “furry” and “ruffled” looking; usually, penguins are slick and beautiful. These “furry” and “ruffled” penguins were going through their molt.

Once a year, penguins have to lose all their feathers to get new ones. Megan says, “It is kind of like if you wear the same clothes every day for a year - you would need new ones because they would be worn out.” Although penguins are not flight birds, their feathers are very important for keeping them warm in cold water. All of their feathers need to be of the same integrity to do this. This Catastrophic Molt takes about a month from beginning to end. During this time, penguins eat twice as much food to get extra weight on their bodies. Out in the wild, they spend almost 1-1/2 to 2 weeks out of the water while their old feathers push out and new ones come in coated with oil from the fat they have stored up from the extra eating.

There are currently 34 penguins at Ripley’s Aquarium of the Smokies, and they eat 40 pounds of fish each day. Megan and her assistant record how much fish each penguin eats per feeding to ensure each is getting the nutrients they need. They are looking to feed each penguin 6-7 fish (their maintaining number). Herring fish is fed the most, but the penguins also like squid, anchovies and penguin-sized mackerel. In the wild, African penguins can hold their breath for 2-5 minutes as they dive down to catch their own food. Megan says, “They can eat most anything as long as it can fit through their mouth and not too fat, plus they can eat several at a time because they swallow everything whole without chewing.”

If you have looked at the pictures closely, you will notice that each penguin has a band on its wing. Each penguin has either a  blue or red band that has the penguin’s name printed on it. Males’ bands are blue and located on their right wing, while females’ bands are red and found on their left wing. Megan says this is how it is done when marking (banding) any species of animals. This method of marking animals allows scientists to quickly determine gender. At Ripley’s, it is important to have their names on the bands also for recording feedings and keeping other records.

Knowing which penguins are which also comes in handy when matching up breeding pairs. Technically, penguins breed as early as 1 year old, but there is more success when females are between 4-5 years old and 7-8 years of age for males. As a part of the Species Survival Plan (SSP) and the Association of Zoos & Aquariums (AZA), Megan says they look at numerous things when matching pairs. One thing is how endangered the animal is and another is how many of that animal are located in zoos and aquariums. The African Penguin has a green level SSP rating and can maintain a 99% diversity level for 100 years as long as the breeding recommendations are kept up. Ripley’s is fortunate to have a lot of genetics to pull from, allowing them to have 11 allotted breeding pairs – 6 of which are extremely valuable. Megan says, “We pair like penguins together: really valuable together, medium valuable together and less valuable together. Extras are sent to other locations for breeding.” The Valuable Rating is determined by how many in a genetic line is born.

Megan and her crew at Ripley’s use a computer program that keeps track of values. When they pick a male and female pair, the program shows how much relationship the two have to each other along with percentage of kinship to all penguins. When pairs bond, their bond lasts for life. When they breed, the female will lay two eggs which are incubated for up to 40 days by both parents. Usually, only one egg will hatch. Parents take turns feeding the chick and keeping it warm for about a month. Chicks get their adult feathers when they are 70-100 days old and go off to sea on their own.

The African penguin is a beautiful bird in their slick black and white feathers. They are fun to watch as they waddle around and dive through the water. I can understand Megan’s love for them and her desire to work with them on a daily basis. Thanks to Megan and others like her around the world, we can see this species and many other animals up close and personal at zoos and aquariums where we can learn to understand how they live in the wild and respect their place in nature. If there is not a local aquarium near you with penguins, visit Ripley Aquariums website where they have a penguin cam set up for you to share with your classroom. Feeding time is always fun to watch!

Stephanie Miller

With over 25 years experience, Stephanie serves as a senior copywriter, social media director, and senior editor for Science Scene. Stephanie is always on the lookout for new educational and STEM-related opportunities and technology.