Once again I return to my 1972 book ‘The World’s Vanishing Birds’; this time to see how some of the American (north and south) birds featured in the book are faring now.
Some of you have likely heard the story of the California Condor, it is the largest North American land bird and also happens to be one of the rarest birds on Earth. In 1972 my book tells me that there were around 40-50 individuals left in the wild, though strangely it fails to state why the species was in such dire straights in the first place. Birdlife International however, informs that the population crash was largely due to persecution (cattle ranchers mistakenly believed the birds preyed on their livestock) and poisoning by ingestion of lead from shot in the carcasses they consumed. Other detrimental influences included DDT poisoning, habitat destruction, death from eating litter and all this was compounded by the low reproductive rates of the Condor – each pair only raises one chick a year. It got so bad that in 1981 the entire world population was reduced to just 22 individuals – drastic action was taken to prevent total extinction when all the remaining wild birds were taken into captivity in 1987. After boosting the population with a captive-breeding programme the species was released back into the wild in 1991. Currently the population stands at 231 individuals, however only 44 of those are sexually mature and the species is still classed as critically endangered because of the continuing risks from lead poisoning, waste indigestion and low reproduction rate – the California Condor is not safe yet.
Another of North Americas rarest birds is the Whooping Crane, which in 1938 had declined to just 15 adult birds – my 1972 book claims only 50 survive in the wild. This crane is a migratory bird which breeds in northern Canada but winters in the southern states; over-hunting, disturbance and loss of wetland habitat had all contributed to its decline across both winter and summer ranges. Thankfully various captive-breeding and release programmes have brought the species back from the edge – though it is still threatened by hunting, droughts, nest predation and most significantly collision with power lines. The bird is still listed as endangered with only 382 individuals remaining – though the population is increasing.
A bird with an interesting past is the Bermuda Petrel; the introduction of non-native mammals to the Bermuda archipelago by colonising Europeans and the direct mass eating of this bird and its eggs by various shipwrecked mariners led to a huge decline, such that in 1620 it was thought extinct. Yet in 1935 a dead bird was found on the Bermuda coast and in 1951 a population of 18 nesting pairs was discovered on tiny rocky islets in the archipelago. According to my book the population was just 70 birds in 1965 – reasons for its low numbers are attributed to pigs and rats destroying nests and human consumption. Major work has been put in by conservationists to try and secure this birds population, including translocating young birds to Nonsuch island to establish another colony, as of now the species is still endangered with 250 individuals and is threatened by tropical storms, yet there is hope.
An extremely colourful endemic to the Caribbean island of St. Vincent is the aptly named Saint Vincent Parrot, according to my book it lives in mountain forest but due to hunting for food it has declined – it claims nothing is known of surviving numbers. Currently Birdlife International states that hunting, capture for pets and deforestation are still threats but conservation action has halted the previous decline through public awareness and protection of habitat. The population is around 730 individuals and is classified as Threatened – its isolation and endemism make it vulnerable to significant events such as disease or storms.
A similar species, but on the island of Dominica, the Imperial Parrot, is not doing quite so well as its cousin. My book does not give a population size but repeats that it is very rare, largely due to deforestation, shooting an trapping. The IUCN happily claims that thanks to education initiatives local hunting and trapping for pets has largely stopped, hurricanes and lack of legal protection of the forests are still threats though as is its low population (250-350, but this is up from 80 birds in 1993) and limited range. It is rightly listed as endangered but may be downgraded to vulnerable if the population continues to increase.