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The peregrine falcon is protected from trade under Appendix I
of CITES. Peregrine populations around the world declined severely
after the Second World War. Prior to the 1940s, there were roughly
7000 Peregrines in North America. In Europe, there were at least
8000 Peregrines. At their lowest point in the 1970s, populations
dropped to several hundred in North America and under 1000 in
Europe.
North American researchers believe that DDT was primarily responsible
for the decline of the peregrine. In Europe, many scientists contend
that while DDT played a significant role, other chemicals were
also at fault. Most notably, two closely related organochlorines
called aldrin and dieldrin are believed to have killed many adult
Peregrines. These two insecticides were widely used to coat seeds
to protect them from insects. Almost immediately, naturalists
noticed that seed-eating songbirds, as well as their predators,
were dying in large numbers. Within less than a decade, the use
of both aldrin and dieldrin was severely restricted in Britain,
and many species began to recover, including the Peregrine.
Signs of hope did begin to be seen. In 1977, a captive bred peregrine
made history by raising a family in the wild. In the years since,
over 4000 Peregrines have been released in North America. Smaller
numbers have been bred and released across Europe. While many
releases appear to have failed, some individuals did survive and
established territories, and populations in many areas are now
slowly increasing each year. The peregrines now living in eastern
North America are all either birds which have been released, or
descendants of captive bred birds. By the late 1980s, there were
again as many as 1200 pairs in North America, and in Europe there
were over 4000. While there are a few locations where populations
have returned to or exceeded historical levels (e.g. Switzerland,
Britain), in most areas the peregrine still has a long way to
go to achieve a full recovery.
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