Saturday, September 5, 2009

ICE ICE BABY Returns to Nest


Dear Icebar Orlando

Ice Ice Baby and our other adopted penguins are now back in the colony after their long winter migration to Brazil and back. They are in excellent condition after months of rest and recreation, which is just as well, because there is lots of work for them to do before egg-laying begins next month.

Penguins do not usually stay with their partners during the winter migration, so they need to meet up again back at the colony before mating and egg-laying can take place. The males arrived in the colony a few days before the females, which is usual. There are always many more male penguins than female penguins, so the males cannot take the risk of loosing their female to another male by arriving late. Female penguins are not tolerant of being stood up, so male penguins must be punctual.

The winter storms cause so much damage to the old nests that they are hardly recognisable in the Spring. Much of the soil gets eroded away by heavy rain, and considerable vegetation growth occurs during the winter due to the availability of much needed moisture around the plant roots. As a result, the nests need to be completely restored and cleared of mud and debris, before they are in a fit state to hold the eggs.

Both partners share the work of repairing the nests, and these activities, along with courtship displays and the preening of each other's feathers, renew the pair-bonds that keep the couple together throughout the season, and often for life. Magellanic penguins are sometimes known as Jackass penguins because of their donkey like call (see attached video clip).

Adult penguins live to 25 or 30 years of age, and have no real predators, so very few penguins fail to return to the colony each year. Orcas (killer whales) do sometimes eat penguins, but there are very few Orcas in the waters around our colonies. Adult penguins are also very skilled at avoiding predators, and most penguins caught by Orcas are the pre-breeding youngsters who have not yet refined their survival skills.

This is one of the reasons that penguins do not begin breeding until they reach

4 or 5 years of age. Penguins need 4 years of practice catching fish and avoiding predators before they are ready to become reliable parents like Ice Ice Baby.

There are sealions in the vicinity of our colonies, but sealions do not really feed on penguins, despite what you may have seen on TV. Some other species of seals do kill penguins for food, such as Leopard Seals, but they only live around Antarctica so are not a threat to Ice Ice Baby.

A very small number of adult male sealions which are unable to secure females do sometimes attack and kill penguins, but they rarely eat the penguin. This behaviour seems to be the result of aggression by frustrated males that have no females, something similar to young lads at a disco, who having been unsuccessful at chatting up a girl, look for someone with whom to pick a fight, or for something to vandalise.

Around Isla Magdalena in Chile we sometimes see this, because there is a sealion colony on nearby Isla Marta, but out of a penguin population of around 140,000 penguins, perhaps a dozen or so penguins are killed each year. So the law of averages dictate that Ice Ice Baby will fall victim to a sealion about once every 10,000 years.

Once the nests are fully repaired, the penguins must wait for the eggs growing inside to finish developing. Egg-laying in Argentina takes place during mid to late October, with egg-laying in Chile and the Falklands taking place about two weeks later, in early November.

As soon as egg-laying has taken place, we will take a photo of Ice Ice Baby sitting on the nest. We cannot take photos before egg-laying has taken place, because the penguins can all too easily abandon the nest if they are disturbed prior to egg-laying. Once egg-laying has taken place however, the penguins will not abandon the eggs except under extreme circumstances, such as the nest becoming submerged by water as a result of heavy rain.

It is for this reason that we must take the photographs after egg-laying has taken place, the timing of which is in the hands of Ice Ice Baby. I will write to you again when egg-laying and photographing have taken place.

In the meantime, you might like to know that scientists have uncovered fossils from the oldest penguin ever found. Discovered in New Zealand and called Waimanu, this penguin is 62 million years old, just 3 million years after the dinosaurs.

Waimanu has a head and beak very similar to a cormorant, and the skeleton strongly suggests that penguins evolved from a common ancestor of cormorants, petrels and penguins. This shows that birds must have been evolving long before the extinction of the dinosaurs, and therefore co-existed with dinosaurs, contrary to previous beliefs.

Best wishes


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