IUCN 10/01/2016 – Least Concern (LC)

U.S. and Canada Conservation Status: Critically imperiled in 1/66 states and provinces (SK). Imperiled in 6/66 states and provinces (LB, NF, YT, DC, NC, NJ, ). Vulnerable in 17/66 states and provinces. Apparently secure in 26/66 states and provinces. Secure in 31/65 states and provinces. Florida subspecies Falco sparverius paulus, listed as threatened.

The data used in this figure are listed above. These data were compiled from NatureServe and the U.S. Fish and Wildlife Service.

The Southeastern subspecies of American Kestrels (Falco sparverius paulus) was listed as a United States Fish and Wildlife Service Bird of Management Concern as of 2011 and the Southeastern American Kestrel range as a continental Bird Conservation Region as of 2021. They are also protected under the Migratory Bird Treaty Act (MBTA).

Throughout the Western Hemisphere from Alaska and Canada to southernmost South America.

Most open habitats with adequate cavities for nesting and perches for hunting. The species readily adapts to human-modified environments, and is frequently seen in pastures and parklands perched along the road. Historically, kestrels have benefited from agricultural expansion but recent changes in farming practices may be affecting populations.

Along with many other raptor species, American Kestrel populations were negatively impacted by the use of DDT during the 1940s through 1960s. Following the DDT ban, American Kestrel migration counts began to rebound. American Kestrel migration counts started declining again in the early 1980s but by 2010 some sites began to observe counts stabilizing. However, numbers have not reached previous levels suggesting the population remains declined. American Kestrel population declines are also evident in Christmas Bird Count and Breeding Bird Survey data in the East and parts of the West, mirroring the timeline of decline shown in the migration counts.

These maps summarize the latest RPI trend analyses for count sites throughout North America.

Find the interactive version of the Christmas Bird Count (CBC) maps here.

BBS: American Kestrel breeding bird trends have been declining since the mid 1960s across North America. Some increases in the Central region of North America were seen but other regions have observed declines with varying severity. Both western and eastern states and provinces have reported declines, with declines being most concentrated in northern regions.

Some possible reasons for American Kestrel population declines include changes in agricultural practices, loss of grassland habitat, loss of prey species, environmental contaminants, and infectious disease. West Nile virus has increased in Canada and the Northeastern United States and American Kestrels are vulnerable to the virus (Saito et al., 2007). Recent increases in wildfire frequency and intensity also may impact western populations.

Although kestrels are well-adapted to human-dominated environments, measures that decrease the amount of foraging habitat and the number of nest sites, such as changes in farming practices, loss of agricultural areas, and increased suburbanization and urbanization negatively impact them. American Kestrels rely on grassland habitat for survival through most of their range. Decreases in farmland along with declines in pasture within farms reduces suitable habitat. “Clean” farming trends with very large fields of row crops planted fence to fence without traditional tree lines, hedge rows, or brushy areas fail to provide suitable nesting cavities and prey resources for American Kestrels. American Kestrels suffer from competition with other species for nest sites as well. European starlings, screech owls, northern flickers and squirrels are prospective nest competitors. Predation by avian predators such as Cooper’s Hawks may have increased particularly in areas near suburban and urban areas. The impact of the overall increase in both number of wildfires and fire severity in Western North America on raptor populations requires further investigation. These changes can result in profound changes in the ecosystem, including vegetation shifts, invasive species, a decrease in biodiversity, and population shifts. Some preliminary research has shown raptors may not use nesting habitat after a fire, which suggests raptors have experienced further declines in usable habitat due to increased fires in the West (Gao, 2020).

Although the use of organochlorines in North America have become heavily regulated, the continuing effects of other agrochemicals including pesticides and herbicides on birds have not been satisfactorily explored. As an insectivorous predator, American Kestrels are especially susceptible to bio-magnification of contaminants ingested by their prey. They also prey on birds which can be exposed to agrochemicals. Exposure to DDT and DDE can cause eggshell thinning and feminization of clutches in kestrels. Anti-coagulant rodenticides (ARs) can also travel up the food chain and have fatal impacts on kestrels and their chicks. More research is needed to determine the extent that ARs impact American Kestrel populations. Because some individuals migrate out of the United States in winter, American Kestrels could be exposed to DDT, DDE, and other agrochemicals still being used in Central and South America.

American Kestrel diet consists of primarily insects and small rodents. One study found in the United States and Ontario that American Kestrel diet consisted of 74% invertebrates. Arthropods, especially grasshoppers, cicadas, beetles, and dragonflies are dietary staples. Insecticides, which can be fatal, can also affect American Kestrel populations by decreasing the amount of their available prey. In 2017, a study found a more than 75% decline in total flying insect biomass in protected areas over a time span of just 27 years (Hallman et al, 2017). More research is needed to assess insect declines in North America.

West Nile virus (WNV) first reached the United States in New York in 1999 and has since spread across the continent. West Nile virus is a zoonotic disease that infects most avian species as well as horses and humans. The primary vectors for WNV are mosquito species Culex restuans and Culex pipiens, while many avian species serve as reservoirs. American Kestrels infected with the virus present neurologic symptoms and mortality. From 2002-2005, 35% of American Kestrels admitted to a wildlife clinic in Fort Collins, Colorado tested positive for WNV (Nemeth et al., 2009). The timing of the decline of American Kestrels in the East region is consistent with the WNV mosquito vector index in Pennsylvania, suggesting the declines in the north eastern US might be related to WNV prevalence in the region (Bolgiano, 2019). American Kestrels are most commonly infected with WNV through a mosquito bite or by injesting an infected bird (Vidaña et al, 2020). In 2007, a study in Pennsylvania found that 21 of 22 birds tested exhibited WNV antibodies, suggesting that most of the adult kestrels in the region had been exposed to WNV (Medica et al, 2007). More research is needed to determine the extent to which WNV has impacted raptor populations, including American Kestrels.

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Learn more about this species natural history at All About Birds or at Hawk Mountain’s website.