Red Robin said:
RoperAB said:
Well Mike I could provide lots of Canadian links that say the opposite about falcons.
I'd be interested in seeing them RoperAB.
Well here are links from the Canadian federal government
http://www.ec.gc.ca/EnviroZine/english/issues/55/feature2_e.cfm
At the most southern point on the Canadian mainland is Point Pelee National Park, home to more than 70 species of trees, 27 species of reptiles, and 20 species of amphibians. The Park is celebrated as the best location in inland North America to observe the northward migration of songbirds, and every autumn, thousands of migrating monarch butterflies gather here to begin their flight to central Mexico. The marsh, which makes up about 70 per cent of Point Pelee, supports a tremendous diversity of life, and is a wetland of international significance.
Recently, scientists have discovered that the Park's well-being is threatened by mid 20th century pest control practices. The unwelcome trespasser at the Park is DDT (Dichloro-Diphenyl-Trichloroethane), a pesticide banned in Canada in the early 1970s.
The History
Point Pelee National Park was established in May 1918, but commercial, agricultural, and residential activities continued for a long time after that. Apple orchards and vegetable fields occupied a large proportion of the south and central area of the Park until the late 1960s, when Parks Canada bought and restored the agricultural lands to natural areas.
Between 1948 and 1970, DDT was used for mosquito control in recreational areas and pest control in agricultural areas. It was applied as a spray over wide areas and also as "toss bombs" at specific sites and open ponds of water within the marsh. With the passage of time, it was thought that DDT would no longer be found there. However, recent studies of wildlife have proved this idea false.
In the 1990s, scientists from the University of Windsor detected high levels of DDT in some of the Park's amphibian and reptiles, and tracked its origin to the shallow soil within the Park. Even after 35 years, DDT was found to persist in the soil – and at very high concentrations. In the shallow soil (0 to 10 cm below ground surface) concentrations have been measured as high as 316 micrograms per gram. This exceeds the Canadian Soil Guideline for Recreational/Parkland land use of 0.7 micrograms per gram – set by the Canadian Council of Ministers of the Environment for the protection of the environment and human health.
Fast Facts
The marsh at Point Pelee National Park has been named a RAMSAR site.
DDT, found to have toxic effect on most animals, was banned in Canada in the early 1970s.
The last application of DDT in the agricultural areas of Point Pelee National Park was about 35 years ago.
Concentrations in the soil in the former agricultural areas range from 0.32 to 316 micrograms per gram. Micrograms per gram is also known as parts per million (ppm).
How Widespread is the Problem?
When this was discovered, Environment Canada's National Water Research Institute (NWRI) began to investigate the extent of DDT contamination and the reasons for its persistence. Research scientist, Dr. Allan Crowe uncovered a good news – bad news story. The good news is that the soil contaminated by DDT at levels above the Canadian Soil Guidelines is confined to the former agricultural areas; the bad news is this is about one quarter of the land in Point Pelee National Park.
Because DDT has an extremely strong tendency to bind to organic matter, it is confined to the upper several centimetres of the soil profile. Unfortunately, this upper several centimeters is the biologically active zone, where many animals live, burrow, and obtain their food - insects, earthworms, and roots. This is why some of the amphibians, reptiles and birds within the Park have elevated levels of DDT and increased levels of mortality.
http://www.pnr-rpn.ec.gc.ca/nature/endspecies/peregrine/index.en.html
Once gone from the Prairies, their numbers are now steadily increasing thanks to an intensive re-introduction program. A ban on the pesticide DDT, which caused their egg-shells to become thin and break, was critical in recovering populations.
http://www.pnr-rpn.ec.gc.ca/community/ecoaction/fp-pf/page.asp?lang=en&id=MB-02013
Peregrine Falcons were nearly wiped out over much of their North American breeding range primarily because of the use of pesticides such as DDT. Even though the use of DDT was banned in the U.S. and Canada in the early 1970s, it is still being used in several countries from Mexico to South America where Peregrines winter. Although the Peregrine Falcon has responded well to recovery efforts, the species is still endangered and in need of assistance.