Saturday, September 27, 2014

Breeding: Candling

Here is a video of a little blue penguin egg being candled several times throughout its 38 day incubation period.

By shining a concentrated beam of light though the egg we can get a glimpse inside to determine if the egg is fertile.

A penguin egg

We first candle the egg when it is about 10 days old.  If it is fertile, we will see a small bean sized embryo with a network of veins. As incubation continues, the developing chick gets bigger and bigger and we begin to see it moving inside the egg. Just before it is due to hatch the chick becomes so big that it takes up the entire available space inside the egg, and the light beam no longer passed through the egg. This means hatching is not far away.

This is the device we use for candling

The Aquarium takes part in a Species Survival Plans for African and little blue penguins. It's always exciting to track the growth of these chicks while they're in the eggs. Candling is an important part of this process.

Stay tuned for more about the breeding season that happened behind the scenes at the Aquarium. Want to learn more about penguins right now? Head down to the Aquarium and dive into our Penguinology program! You'll learn about the secret world of penguins and some amazing facts about these birds living at the Aquarium. Plan a visit!

Saturday, August 23, 2014

Breeding: The Best Nest

For penguins an important first step to breeding success is having a proper nest. Among the penguin species you will find several different types of nest styles.

Many penguin species are considered surface nesters. This means they will collect materials and build a nest directly on the ground. The type of materials used to build the nest depends on the species and what is available. For example Adélie and gentoo penguins will collect rocks and pebbles, rockhopper penguins will use pebbles along with pieces of vegetation and even bones.

Gentoo penguins nest in a mound of pebbles | Photo: Brian Skerry, Aquarium Explorer in Residence

 Rockhopper nest

Some penguin species are considered burrow nesters. These penguins will dig burrows in the substrate (often seabird guano) or under vegetation, to protect their nest from the hot sun and avian predators.

African penguin burrows on Dassen Island

Once a burrow is made the penguins will then collect pieces of vegetation to line the nest. In some penguin habitats where suitable areas have been destroyed, humans have added artificial burrows to help promote breeding and  increase penguin populations.

Magellanics in burrow

Manmade burrows on Dassen

Another unique and well-known strategy is no nest at all. Emperor and king penguins do not build nests but instead hold their single egg on their feet to keep it warm.

Emperor penguins incubate on their feet, tucked under a fold of skin
Photo: Hannes Grobe/AWI via Wikimedia Commons

When we bring our breeding pairs behind the scenes we make sure they have the ability to build a nest that suits their nesting strategy. Since African and little blue penguins are burrow nesters we provide them with a burrow using a litter box top. We provide plastic aquarium plants to line their burrow nest. Building a nest it is a good sign that a mated pair is comfortable and ready to lay eggs.

Stay tuned for more about the breeding season behind the scenes at the Aquarium. Want to learn more about penguins right now? Head down to the Aquarium and dive into our Penguinology program! You'll learn about the secret world of penguins and some amazing facts about these birds living at the Aquarium. Plan a visit!

Monday, August 18, 2014

Breeding: Summertime Fun

To most people summer means no school, vacations, barbeques and going to the beach.  To the penguin staff it means breeding season.

Earlier this spring we brought four of our SSP-approved (meaning specifically chosen to produce a genetically healthy and diverse population) little blue penguin breeding pairs behind the scenes to start the breeding season. Just recently, seven of our SSP-approved African penguin breeding pairs joined the little blue penguins in our behind the scenes breeding area.

Little blue penguin pair behind the scenes

African penguin pair behind the scenes

Over the next few months we hoped these penguins will bond, lay eggs, and raise penguin chicks before they are returned to the exhibit. We have had very successful breeding seasons over the years and we are hoping for another successful breeding season this year.

Wishful thinking!

An “armful” of African penguin chicks from a previous breeding season; we are hopeful this year will be just as successful.

Check out these past blog post from past breeding seasons:

And check back often for updates from this year’s season!

A pair of African penguins behind the scenes in their burrow

Monday, August 4, 2014

Penguins in Peril: Introduced Predators

You have probably learned through school or even from watching the Disney movie The Lion King, that many organisms are interconnected to each other in an ecosystem through predator/prey relations (aka the Circle of Life).  On occasion non-native organisms are introduced into an environment, and can be disruptive to the ecosystem, as they compete with the native organisms for resources. These new neighbors are often called introduced, non-native or invasive species.

For example: lionfish are native to the Indo-Pacific and in recent years have been found in coral reef communities in the Atlantic Ocean. Since lionfish are excellent hunters and have no natural predators in the Atlantic, researches are seeing their population bloom while the populations of the native reef species are declining.

Lionfish in the Caribbean | Photo: Sarah Taylor via Bahamas Expedition blog 

As Europeans ventured around the world they often brought with them species from their homeland either intentionally or by accident. Penguins breed in isolated areas or on islands with little to no land predators. The introduction of non natives like foxes, rats, feral cats and dogs added land predators that penguins previously never encountered. These new species kill the adults, chicks and eggs of many penguin species like the little blue, Galapagos and African penguin. Over the years researches have seen penguin populations decline as a result of introduced predators.

Fox and penguin | Photo credit: Philip Island – Nature Parks Australia

Stay tuned to future blogs to see some creative solutions to help combat introduced predators.

Tuesday, July 29, 2014

Penguins around the world: Yellow-eyed penguins

The African, rockhopper and little blue penguins here at the Aquarium allow visitors to get to know three very interesting penguin species. There are 15 other interesting penguin species in the world just waiting for you to discover them. Over the next couple weeks, we will introduce more penguin species!

The yellow eyed penguin gets its name from their characteristic, pale yellow eyes and the yellow band of feathers that wraps around their head. Their scientific name is Megadyptes antipodes which means the “big diver from the southern lands.”

Yellow-eyed penguin | Photo: Ville Miettinen via 

Yellow-eyed penguins are found off the southern coast of New Zealand and the sub-Antarctic islands of Auckland and Campbell. The yellow eyed penguin is the largest species of temperate climate penguins; standing at about 25-30 inches and weighing in between 12–18 pounds. The Maori tribes of New Zealand call the yellow eyed penguin hoiho which means noise shouter and refers to the shrill calls of the penguins.

A yellow-eyed penguin crying | Photo: Christian Mehlführer via

In addition to their unique appearance yellow eyed penguins are unique in the fact that they do not breed in large crowded colonies.  Unlike most penguin species that breed in very close proximity to their neighbors, yellow eyed penguins breed in the coastal forests of New Zealand and prefer to not be in eyesight of other breeding pairs.

Yellow-eyed penguins on the beach in New Zealand | Photo: Bartux via

Yellow eyed penguins are endangered, with only about 4000 individuals remaining. Deforestation is a major factor in their population decline. Their breeding habitats have been cleared to make pastures for livestock. The introduction of foxes and stoats (a weasel-like animal) in the early 1800’s also added extra pressure to a declining population.

To help protect these unique penguins many conservation groups (like this) have been set up throughout New Zealand and many of the yellow-eye penguins breeding areas have been made protected areas.

Stay tuned to the blog to learn more about other fascinating penguin species.

— Andrea

Love penguins? Get to know macaroni penguins in this previous post. Better yet, come visit the Aquarium to see three species of penguin up close! There's so much to learn about these amazing little birds, so don't miss our exciting summer program called Penguinology.