In 1862, when D.F. Eschricht reported finding the remains of 14 seals and 13 porpoises in the stomach of one orca floating off the coast of Jutland in the North Sea, he bolstered public opinion that orcas were killers and mindless, shark-like, eating machines. Over time, this image changed, and captive orcas became popular exhibits at oceanariums. Ironically, the more scientists began to realize the intelligence and individual character of these marine mammals, the more orcas became victims to a lifetime of marine-park captivity.
After a decade of live captures in the mid-1960s to mid-1970s, the Pacific Northwest (or "southern resident") orca population was reduced to 68 mostly adult individuals, since the young were selected first for removal. There were no exact whale population figures prior to this cropping, nor are there exact removal statistics, but it is estimated that approximately 50 orcas were taken and that the population was reduced to below its optimum sustainable level as defined by the Marine Mammal Protection Act of 1972. The captures ceased in 1976, leaving a questionably viable population.
At the time of these captures, nobody knew how long a killer whale lives, how long it takes to mature, how many babies a female produces, or whether the populations were resident or transient. From historic whaling and stranding data, wildlife managers knew only that, in some parts of the world, these animals grow to be about 7 to 10 meters (23 to 33 feet) in length, are sexually mature at around 5 meters (17 feet), and that males can weigh up to 39,600 kilograms (9 tons). Females are notably smaller than males and apparently more numerous, which suggested a polygamous mating system.
To this day, it is unknown if the Puget Sound population or its ecosystem is viable in the face of increasing human activities that pollute, damage, and consume the resources; salmon, which are a prime prey resource for orcas, are one of the several marine species which are in danger in the Pacific Northwest as a result of over-fishing and human river development. Their passing to extinction does not bode well for the predators, including humans. Besides accumulating general orca knowledge, our immediate goals are to generate publicity which can spur the necessary support for reducing these damaging activities.
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