Until recently they were not regarded as a significant commercial species, and so little data has been collected on them. No-one knows how many cuttlefish live off the coast of Australia. ^ to top Cuttlefish exploitation and the albatross' future
Then, in a little more than a year after raising another chick, they will prepare to return once again to the cuttlefish breeding grounds which have always sustained them.Ĭuttlefish die once their mating is complete Cruising at about 50km/hr, they will be back in their breeding islands by November, having covered 20,000 km in just two months. It will be time for the albatrosses to begin the long return to their nesting sites to raise another chick. The Wollongong cuttlefish appears to satisfy this need, according to Harry Battam.īy September, the cuttlefish will all be gone. Hence its need when breeding is finished, for a concentrated supply of food to restock its fat reserves. However, when an albatross is working hard to feed a growing chick, it may exceed its sustainable metabolic rate, and so lose weight and condition. For example, a cyclist riding in the Tour de France has a sustainable metabolic rate about four times that of the basal rate.īut an albatross may have a maximum sustainable metabolic rate of perhaps twice its basal rate - in other words, they use energy very frugally to accomplish what they need to do. All living creatures have a basal metabolic rate (the rate of metabolism at rest) and a maximum sustainable metabolic rate (the rate above which an organism will lose weight, no matter how much food is eaten). The answer may be in the metabolism of the albatross itself. ^ to top How can a diet of cuttlefish sustain such a large bird? She lays between 100 and 300 eggs on the underside of a rock or in an underwater cave. After a delicate dance and display lasting hours, the male uses a specially modified tentacle to transfer a packet of its sperm into the female's body. Their life history is still largely unknown, but we do know that they have a beautiful and complex mating ritual. The cuttlefish spawn only once, and then die. Wollongong is a particular focus for cuttlefish activity because the rocky reefs just offshore make an ideal breeding ground, and they aggregate in their thousands to breed. During their short lifespan of just two years, these amazing creatures grow from one centimetre long up to 1.5 metres, with males weighing up to 15 kilograms. If you walk along a beach anywhere from Perth to Brisbane around July you might be lucky enough to find a giant cuttlefish ( Sepia apama) washed up on the sand. This rich raft of food is one of the few refuelling stations in Australia which provide the albatross with the energy to make their extraordinary journey - up to 20,000 kilometres - to and from the other side of the world. They have come to feast on dead and dying cuttlefish which float to the surface, completely spent after their annual breeding frenzy. Every year, in early July, thousands of albatrosses converge on a small area off the coast of Wollongong. The feast is an annual freak of nature, and its participants are among the most magnificent birds on the planet - the wandering albatrosses. Albatrosses enter the deadly zone, Science Online,.Albatross facing extinction warns scientist, Science Online,.Albatross at risk, says Greenpeace, Science Online,.
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