Global Short Term Trend: Increase of 10 to >25%
Comments: Populations in the Northern Hemisphere declined drastically from the 1940s to the 1970s due to DDT and its breakdown products, notably DDE, in the environment. During the 1930s and 1940s there were at least 200 breeding pairs in the eastern United States. By the mid-1960s these were all inactive (U.S. Fish and Wildlife 1993). Populations were reduced by an estimated 80-90% in the western U.S. by the mid-1970s; the decline in Alaska probably was no more than 50% (The Peregrine Fund 1992). Populations have been recovering, aided by reintroductions in some areas. In the early 1980s, continent-wide population was stable, but local increases and declines were continuing (see White et al.  for 1980 status in specific areas). See also Cade et al. (1988) and Palmer (1988). Eastern U.S. population was about 210 active nests and 350 pairs in the 1930s and 1940s; population dropped to zero breeders by the mid-1960s, largely the result of eggshell thinning caused by pesticide and PCB poisoning. Populations increased after U.S. DDT ban and initiation of reintroduction efforts. Populations in Alaska, and the Yukon and Northwest Territories evidently have recovered. In interior Alaska, numbers increased about 3-fold from the mid-1970s to the early 1990s; pesticide levels have been decreasing and in the early 1990s were well below levels at which reproduction is impaired. Populations increased from 1985 to 1990 in the Yukon Territory, but full occupancy of the historic range had not yet occurred. Populations in the Mackenzie River valley increased from 1985 to 1990, but little is known of population trends in the boreal forest east of the Mackenzie valley (USFWS 1991). Subspecies TUNDRIUS: In the Northwest Territories, populations are stable or increasing in all surveyed areas (e.g., see Shank et al. 1993); some organochlorine contamination remains, but falcons are reproducing well. In Quebec, breeding performance and habitat occupancy have increased greatly since the 1970s. Overall, in Canada, populations are stable or increasing (Holroyd and Banasch 1995), and there is a continuing danger of organochlorine contamination (Bromley, 1992 COSEWIC report). In Greenland, habitat occupancy had increased to about 90% in 1990 (USFWS 1991). See USFWS (1993) for additional documentation of the recovery of this subspecies. In Alaska, the number of pairs of subspecies ANATUM and TUNDRIUS both have more than doubled in some areas, without the aid of releases (The Peregrine Fund 1992). Censuses indicate that subspecies TUNDRIUS throughout its range (USFWS 1994) and subspecies ANATUM in Alaska and the Yukon and Northwest Territories have recovered. A significant increase was recorded in migration counts in northeastern North America, 1972-1987 (Titus and Fuller 1990). With the exception of the central and western prairie provinces, reported to have recovered throughout much of Canada (The Peregrine Fund 1992). Stable or increasing in northern and western Canada; numbers remain low in southern Canada (Murphy 1990); subspecies PEALEI (breeds along British Columbia and Alaska coasts) and subspecies TUNDRIUS (breeds in arctic, winters in Latin America) seem secure (Peakall 1990). The Peregrine Fund (1992) recommended that the peregrine, including both subspecies in Alaska be delisted in all western states except Idaho, Montana, Oregon, Washington, and Wyoming (where a change to Threatened status was recommended). Subspecies CALIDUS: Declined in northern Eurasia during period of intensive organochlorine pesticide use, but now increasing (Quinn and Kokorev 2000).