JUser: :_load: Unable to load user with ID: 82

Aroa’s seal of approval and zoology

Friday August 02, 2013 Written by Published in Economy
Aroa’s seal of approval and zoology

He has lived in a bathtub for a day, he has swum around the sunny shores of Rarotonga and he has dined on sardines.

He is Aroa, the seal that has stolen the hearts of tourist and locals alike.

Aroa has been the center of so much attention – and being under the spotlight is hard for this one-year-old fur seal from New Zealand.

The New Zealand fur seal found here is far out of his natural territory. He was picked up during stormy weather around July 14, but people reported spotting him two weeks before that.

It has been assumed that the reason why the seal is here in the first place is that he was caught in a current and separated from his mother. Several calls were made to try to find a way to get the seal back to his home colony. However, because of restrictions with airlines it is not possible to fly him back to New Zealand.

Since he has been in the Cooks he has not been eating properly – even though Ocean Fresh kindly and quite generously offered him a whole carton of sardines.

He seems to be in good health and appeared to have been eating on his own, so it was thought the best course of action was to put him back where he was found so he could forage on its own. However, a well-meaning tourist picked up the seal and took it to Esther Honey where they took him and promptly returned him back to shore.

It is in the best interest of both people and the seal that no attempt is made to move him, swim up to him or interact with the animal in any way. Seals are not the cute cuddly creatures they seem to be – they have sharp teeth and they use them. It is best to observe the New Zealand fur seal from a distance. Dogs should also be kept at a safe distance from the seal. Allowing the seal enough space protects both you and the animal, as seals have the potential to bite and inflict serious wounds.

Seals are carnivorous aquatic mammals which means they eat meat and mostly live in water, with front and hind feet modified as flippers or fin feet and can be broadly divided in two sub species; eared seals (fur seals, walrus and sea lions) and earless seals – also called true seals.

The name ‘seal’ is sometimes broadly applied to any of the fin-footed animals including fur seals, walruses, eared seals and the true seals.

Fur seals, sea lions and walruses are able to turn their hind flippers forward for walking on land. They swim like they are rowing. The true seals cannot rotate their hind flippers and they progress on land by wriggling their bellies and pulling themselves forward by their short front flipper and they move side to side in water with the aid of their hind flippers to propel themselves forward.

Seals can detect prey with their whiskers, by detecting vibrations from other organisms. Their diet is mostly restricted to fish and squid.

Seals can dive deeply and for extended periods (up to two hours for some species) because they have a higher concentration of hemoglobin in their blood and large amounts of myoglobin in their muscles (both hemoglobin and myoglobin are oxygen-carrying compounds). Therefore, when diving or swimming, they can store oxygen in their blood and muscles and dive for longer periods than we can. A seal has a clear membrane that covers its eyes underwater. Like cetaceans, they conserve oxygen when diving by restricting blood flow to only vital organs and slowing their heart rates by about 50-80 per cent. In a study of northern elephant seals, the seals’ heart rates went from about 112 beats per minute at rest to 20 to 50 beats per minute when diving.

Nearly all seals inhabit cold or temperate regions and they have several natural predators including sharks, orcas (killer whales) and polar bears. But the biggest threat to seals is humans.

The main differentiating characters between a male and a female seal are in regard to diving. Females can dive for about nine minutes and to a depth of about 312 metres. But females can dive deeper and longer in autumn and winter. Males can dive for about 15 minutes to a depth of about 380 meters. On average New Zealand fur seals only dive for one to two minutes. When communicating males vocalize through a bark or whimper, either a guttural threat, a low-intensity threat, a full threat, or a submissive call. Females growl and also have a high-pitched wail call to attract their pups.

Female New Zealand fur seals mature between four and six years old, and males mature between eight and ten years old. These seals are polygynous – where males mate with more than one female. Males obtain and guard the territory in late October before females arrive.

Aroa the seal is very far from home, so let’s work together to protect him and keep him safe while he’s here with us in Rarotonga.

Leave a comment