However, once the species had successfully spread to more productive land at lower altitudes, it became obvious that this was almost entirely due to poor habitat conditions. It was for a long time believed that the lack of genetic variability caused by the bottle-neck had resulted in the low reproductive rate. This was followed by poor breeding success in the early 1960s, thought to be caused by effects of organochlorine pesticides. Until about 1950 when protection measures were starting to take effect, illegal poisoning, egg collecting and shooting of adults for taxidermy were severely affecting the population.ĭuring the 1950s the rabbit myxomatosis outbreak devastated a main food supply of the kites. The population inhabited an area where the climatic conditions and poor food availability depressed breeding success and prevented the birds from expanding their range. There were many reasons for the slow recovery. The population did not exceed 20 pairs until the 1960’s, when it started slowly to increase. Even though several pairs survived, DNA analysis has since discovered that the entire Welsh population was derived from a single female bird. The tightest genetic bottle-neck came in the 1930s. The small remnant population survived the persecution in the old oakwoods in the undisturbed upland valleys of mid-Wales, but despite extensive efforts, the numbers remained extremely low. By 1903 when protection efforts started, only a handful of pairs were left in remote parts of central Wales. Consequently, the red kite became extinct in England in 1871 and in Scotland in 1879. As the kite became rarer, it became a target for taxidermists and egg collectors, whose actions hastened the species towards extinction. The persecution continued through the following centuries largely by game keepers, who wrongly accused them of taking game. However, by the 16th century a bounty was placed on its head and, in common with many other birds of prey, it was relentlessly persecuted as 'vermin'. In the UK the red kite was a valued scavenger during the Middle Ages that helped keep streets clean and was protected by a royal decree killing a kite attracted capital punishment. This resulted in the species becoming extinct in several countries following a marked long-term decrease in range and numbers.
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