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Peregrine Falcons


Project Leader: Melanie Flamme

Status: In development

Implementation year: 2006


Resource Brief

References on the Integrated Resource Management Applications (IRMA) Portal

The number of occupied territories within the study area, which is located within Yukon-Charley Rivers National Preserve, has shown a steady increase since the species neared extinction in the early 1970s because of nest failure caused by DDT contamination. In 2007, 50 occupied territories were observed, which is nearly a 5-fold increase since 1975.

Reproductive success has improved during the past 3 decades. The number of nestlings, though variable among years, has increased from 17 in 1975 to 82 in 2007. Recent evidence suggests that American Peregrine Falcons are still threatened by environmental contaminants, though. Analyses of Peregrine eggs from the upper Yukon River suggest that mercury levels are increasing. Mercury is a persistent compound which bioaccumulates at high trophic levels and causes toxic effects (similar to DDT). The amount of mercury being found in Yukon area eggs is currently at levels that may affect reproduction. High levels of mercury are made biologically available through industrial processes such as mining and waste incineration, and will likely increase with global industrialization. Additionally, DDT and other pesticides are still being used on Peregrine wintering grounds, which may cause continued risk to the population.


Each summer, Peregrine Falcon monitoring is conducted along 265 km (165 mi) of the Yukon River between Circle, Alaska, and the border of Yukon Territory, Canada. The basic approach follows guidelines established in the Monitoring Plan for the American Peregrine Falcon (US Fish and Wildlife Service 2003).

Collecting data on nesting territory occupancy, nesting success, and productivity requires two annual surveys conducted by boat along the upper Yukon River. All potential nesting territories along the river are observed from shoreline or islands using binoculars and spotting scopes. Observations are conducted for a minimum of 4 hours at each potential nesting territory.

Collecting data on environmental contaminants requires visiting nests using standard rock climbing techniques. During these visits, the number of young are counted, prey remains are checked, and unhatched eggs and feather samples are collected for analysis.


  • 1. Determine annual levels of nesting territory occupancy, nesting success, and overall population productivity. Justification: Occupancy of nesting territories is an index of population stability. Nesting success and productivity are important measures of population health and indicators of density dependent responses to increases in population size and nearest-neighbor distances.
  • 2. Determine variation in nesting territory occupancy, nesting success, and productivity during the last decade. Justification: Quantification of variation in these parameters is needed to develop realistic monitoring goals for the future.
  • 3. Describe historic levels of environmental contaminants and eggshell thickness. Determine levels of organochlorine pesticides, mercury, and eggshell thickness every five years. Justification: Current levels of organochlorine pesticides and their residuals in peregrine falcons in Alaska are low enough to allow for successful reproduction and expansion of the populations (US Fish and Wildlife Service 2003). However, current levels of mercury in peregrine falcons in YUCH can affect reproduction and may have increased over time (Ambrose et al. 2000). The continual introduction of anthropogenic chemicals into the environment far outpaces research on their effects on peregrines and other wildlife and therefore warrants continued monitoring in YUCH (U.S. Fish and Wildlife Service 2003).
  • 4. Measure changes in habitat on the breeding ranges. Justification: Peregrine falcons are very adaptable to changes in their habitat (U.S. Fish and Wildlife Service 2003); however, largescale changes in their breeding habitat could negatively affect the individual pairs and/or portions of the breeding population.


Name Role Organization Telephone Email
Melanie Flamme Project Leader National Park Service 907.455.0627 Email Melanie Flamme
Robert Ambrose Project Leader Sandhill Company Email Robert Ambrose
John Burch National Park Service 907-456-0505 Email John Burch
Chris Florian Sandhill Company Email Chris Florian
Nikki Guldager Collaborator U.S. Fish and Wildlife Service Email Nikki Guldager
Maggie MacCluskie Network Coordinator National Park Service 907.455.0660 Email Maggie MacCluskie
Angela Matz Project Leader U.S. Fish and Wildlife Service Email Angela Matz
Carol McIntyre Project Leader National Park Service 907.455.0671 Email Carol McIntyre
Scott Miller Data Manager National Park Service 907-799-6229 Email Scott Miller
Joshua Schmidt Biometrician National Park Service 907.455.0661 Email Joshua Schmidt


Year Type Title IRMA
2008 Published Report Download National Technical Report good-PEFA2007.pdf American Peregrine Falcon (Falco peregrinus anatum) Monitoring along the Upper Yukon River in Yukon-Charley Rivers National Preserve, Central Alaska Network.
2008 Published Report Download YUCH_Peregrine_2008_ann_rep.pdf American peregrine falcon (Falco peregrinus anatum) monitoring along the Upper Yukon River in Yukon-Charley Rivers National Preserve, Central Alaska Network: 2008 report
2005 Unpublished Report Download 2005_pefa_upper_yukon_river.pdf American Peregrine Falcon Monitoring Along the Upper Yukon River, Yukon-Charley Rivers, Alaska, 2005
Project Monitoring Peregrine Falcons in the Central Alaska Network of National Parks (No holdings available)

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