Penguin-thiefs free - case dropped : South Africa court drops case against penguin thieves | Daily Mail Online
Been reading an article in issue 16 of the International Zoo Yearbook about an attempt by the Port Elizabeth Oceanarium to keep two young female crabeater seals, both caught on beaches near to Port Elizabeth. The first was caught in 1973 and the second in 1974. I figured I would post the information here, just for general interest. The first seal was already starved on arriving at the Oceanarium and refused benthic invertebrates (mud prawn, shrimp or crab) as food. It began to show an interest in live mullet that had been placed into its pool but was unable to capture them so was provided with live Mozambique tilapia with trimmed fins. She ate two, although appeared to struggle with swallowing them - the first feeding was two or three weeks after arriving. The following day, she took headless pilchards put in the pool with her and within four days was taking up to 4kg of pilchards a day from the keeper's hands. The diet was gradually increased to include Natal pandora (or redfish), Atlantic horse mackerel, chub mackerel and Cape hake. The second seal began feeding on tilapia after four days but was shifted onto a diet of marine fish by withholding all food for one day (because the only source of tilapia was from a lake polluted with industrial waste water). Both seals gained weight and grew on this diet, with seal 2 growing twenty centimetres in length over the course of her time in the Oceanarium. Both seals tamed quickly, approaching the keeper as soon as a food bucket became visible. After feeding both animals nuzzled the bucket and the keeper's legs, hauling themselves out of the water to do so if they could not reach. The first seal was moved into the main seal pool that contained seven Cape fur seals and two young Southern elephant seals. The second crabeater seal was housed in an enclosure with African penguins and Cape gannets. Both animals, collected in the Januaries of their respective years, both lived until April of that year. The first seal was harassed by the fur seals in the mixed enclosure to the extent where on the second day it refused to enter the water or approach the keeper for food. Over this period, the seal's weight dropped 22% from the previous week and it was thought that the seal died of stress overwhelming a system that had been left vulnerable by the period of starvation. Also, on the week of this seal's death, the temperature rose above 30 degrees on three days, while in the previous three months it had risen that high only twice. The second seal was moved into a pool better-suited for display but had an adverse reaction to the immobilisation drugs. It died three days after the move, having refused food the day before. It was thought likely that the drugs interfered with its temperature control and allowed the animal to get dangerously overheated (the post-mortem revealed the muscles and internal organs had decomposed to paste and lacked any form, just 14 hours after she was last seen alive), which was the main contributor to its death. It was considered at the end of the article that the seals may be suitable for longer-term husbandry, as they adapted well and grew on a fish diet. There would need to be means of chilling the water to avoid debilitating heat effects. It was mentioned that public reaction to the seals (even though they weren't displayed particularly effectively) was most favourable. It is also mentioned that the species could be maintained for research purposes, allowing the provision of renal data on an animal living largely on a plankton diet, as baleen whales are too large to keep in captivity.
