Falcon Population Research Articles

Cascading effects of climate variability on the breeding success of an edge population of an apex predator.

Large‐scale environmental forces can influence biodiversity at different levels of biological organization. Climate, in particular, is often associated with species distributions and diversity gradients. However, its mechanistic link to population dynamics is still poorly understood.Here, we unravelled the full mechanistic path by which a climatic driver, the Atlantic trade winds, determines the viability of a bird population.We monitored the breeding population of Eleonora's falcons in the Canary Islands for over a decade (2007–2017) and integrated different methods and data to reconstruct how the availability of their prey (migratory birds) is regulated by trade winds. We tracked foraging movements of breeding adults using GPS, monitored departure of migratory birds using weather radar and simulated their migration trajectories using an individual‐based, spatially explicit model.We demonstrate that regional easterly winds regulate the flux of migratory birds that is available to hunting falcons, determining food availability for their chicks and consequent breeding success. By reconstructing how migratory birds are pushed towards the Canary Islands by trade winds, we explain most of the variation (up to 86%) in annual productivity for over a decade.This study unequivocally illustrates how a climatic driver can influence local‐scale demographic processes while providing novel evidence of wind as a major determinant of population fitness in a top predator.

Home Range of an Adult Female Peregrine Falcon (Falco peregrinus) during the Breeding and Non-breeding Seasons in Kentucky, USA

The peregrine falcon (Falco peregrinus) is a Species of Greatest Conservation Need in Kentucky's State Wildlife Action Plan. The Kentucky Department of Fish and Wildlife Resources has monitored Kentucky's peregrine falcon population since 1997. However, research on the movements, habitat use, and breeding and non-breeding home range of Kentucky's nesting peregrine falcons is lacking. In this study, we used a solar-powered platform transmitter terminal (PTT) with global positioning system (GPS) and Argos capabilities to monitor the movements of a single adult, breeding female, peregrine falcon from 7 June 2015 to 4 May 2018. We found that the female falcon spent the majority of her time in close proximity to the nest site throughout the breeding and non-breeding season. Seasonal home range varied significantly with the largest home range size estimated during the post-fledging period, followed by the non-breeding season, and the smallest home range occurring during the pre-fledge period of the breeding season. We suspect that the increase in home range size observed during the post-fledging period can be attributed to parental care and post-fledge dependency of young.

Variation in Electrocution Rate and Demographic Composition of Saker Falcons Electrocuted at Power Lines in Mongolia

We examined variation in the number and demographic composition of electrocuted Saker Falcons (Falco cherrug) in Mongolia. We found 1721 electrocuted Saker Falcons during our surveys of multiple power lines in 2013–2015 and 2018. At a single power line surveyed over a 16-mo period in 2013–2014, the lowest electrocution rates occurred from December to March, with a rise in April coinciding with the return of migrant juveniles from their wintering areas. Electrocution rates rose sharply during juvenile post-fledging dispersal, and then declined in October as migrants departed. Monthly changes in electrocution rate and age profile reflected predicted variation in abundance and age structure of the local Saker Falcon population. We found that 88% of electrocuted Saker Falcons were juveniles, mostly killed during their first calendar year. The sex ratio of electrocuted juveniles fledged in the 2013 cohort (hatch-year birds) was significantly female-biased, in contrast to the equal sex ratio of the 2012 juvenile cohort (second calendar-year birds) killed in the same year (2013). Sex ratio of the 2013 juvenile cohort did not differ significantly from parity at other power lines across Mongolia, indicating that sex ratio of electrocuted juveniles can vary in time and space. The sex of electrocuted adults, predominantly males, and an age profile of breeding Saker Falcons that includes younger females suggests a possible male-biased sex ratio among adult Saker Falcons in Mongolia. Given that large numbers of endangered Saker Falcons are electrocuted annually in Mongolia, our study suggests electrocution may be an important driver of demographic trends that can potentially result in population declines.

Phylogeography of the rare Australian endemic Grey Falcon Falco hypoleucos: implications for conservation

SummaryThe Grey Falcon Falco hypoleucos is one of the world’s rarest raptors, with an estimated population size of fewer than 1,000 individuals. Our knowledge of threats posed to the Grey Falcon remains scant. Understanding the genetic variation in this species would help to assess its conservation status more realistically and its prospects for survival in a changing environment. We amplified the cytochrome b region of mitochondrial DNA from the feathers of 26 individuals captured from the wild across the distribution of the species and assessed the genetic diversity and spatial genetic structuring of the species. Genetic diversity was low, with only six haplotypes identified, but there was no evidence of a recent genetic bottleneck. No population genetic structuring was detected, indicating that the Grey Falcon population is effectively continuous across the species’ entire distribution, covering much of Australia’s arid/semi-arid zone. Our results indicate that the Grey Falcon should be managed as a single population and suggest conservation efforts that benefit the species at a local level should be good for the species as a whole. Future studies should employ next generation sequencing approaches, which may provide finer-scale information on the extent these birds move among breeding sites. Further research into the species’ ecology is also required to identify effective conservation measures.

Temporal Genetic Diversity and Effective Population Size of the Reintroduced Aplomado Falcon (Falco femoralis) Population in Coastal South Texas

Temporal Genetic Diversity and Effective Population Size of the Reintroduced Aplomado Falcon (Falco femoralis) Population in Coastal South Texas

Predicting reintroduction costs for wildlife populations under anthropogenic stress

Abstract In conservation decision‐making, it is important to have information not only on the likely effectiveness of conservation actions, but also on the corresponding costs. Reintroduction of wildlife is a commonly applied ‘last resort’ conservation measure. However, a quantitative approach to predict the costs of reintroduction for sustaining a wildlife population under the influence of time‐varying anthropogenic stress is lacking. Here, we fill this gap by quantifying the costs of reintroduction as a function of exposure to an environmental stressor and the size of the wildlife population to be maintained. Our approach combines quantitative stressor–response relationships for vital rates (reproduction and survival) with a wildlife demographic model to compute the impacts of the stressor on the size of the target population. Subsequently, cost estimates are obtained by quantifying the number of captive‐reared individuals needed per year in order to maintain a user‐defined population size, given the exposure to the stressor of concern. We applied our approach to calculate the reintroduction costs required to restore a minimum viable population (MVP) of peregrine falcons (Falco peregrinus) in California over the period 1970–1994, when the population was exposed to the toxicant dichlorodiphenyldichloroethylene. Assuming a gradual yearly increase of 150% in the availability of captive‐reared young, 1,753 captive‐reared young were required to restore and maintain a MVP of 238 adults. The corresponding reintroduction costs were in total ~$3,023,000. Assuming lower reintroduction efforts (in terms of the availability of captive‐reared young), the projected reintroduction costs decreased by ~33%. However, the population then reached the minimum viable size only 9 years later, thus reflecting a trade‐off between costs and population viability. Synthesis and applications. The approach presented in this study ensures an adequate prediction of the costs of maintaining a wildlife population at a user‐defined size through reintroduction. It can be applied to any wildlife population in order to obtain the number of individuals and corresponding costs required to sustain a population under current and future influence of an anthropogenic stressor. This type of information provides important input for decision‐making necessary to conserve biodiversity.

Population recovery of peregrine falcons in central Norway in the 4 decades since the DDT-ban.

The breeding population of peregrine falcons (Falco peregrinus) in Norway was almost exterminated by the early 1970's. Long-term monitoring of breeding pairs has been conducted since 1976 up to present. Peregrine falcons were first established at breeding sites in coastal habitats, where they remained at stable low numbers until the early 1990's. Starting around 2000, numbers began to increase steadily, and current numbers have now reached historical population levels from the pre-DDT era. We documented a range expansion with increasing numbers of peregrines nesting in the fjords and inland valleys. We found that once a territory was colonized, the probability that a territory remained occupied was high (S > 0.958). During early stages of population recovery, the transitional probabilities of becoming or remaining a breeding territory were high (ψN-B > 0.40, ψB-B > 0.65) but declined over time, especially in coastal habitats. Moreover, the productivity per nest has also decreased over time at sites in coastal habitats in the former stronghold of the population. The levels of environmental pollutants in eggs of the peregrines have dropped sharply over the last few decades, and contaminant levels now seem to be below critical levels. Eggshells were relatively thin throughout the 1970s, 1980s, and 1990s, but have increased to almost normal levels during the last 2 decades. Reductions in levels of organochlorine pollutants, especially DDT, appear to have been the main factor in explaining the population recovery. The territory dynamics are consistent with density-dependence and the low breeding success of the coastal-breeding peregrines is believed to be caused by declining numbers of colonial seabirds and other prey species.

Falconry Threatens Barbary Falcons in the Canary Islands Through Genetic Admixture and Illegal Harvest of Nestlings

Peregrine Falcons (Falco peregrinus) on the Canary Islands are considered to be of the Barbary Falcon subspecies (F. p. pelegrinoides). Here we report on lost falconry birds present among the wild population of resident falcons, and provide rough approximations of their abundance for Tenerife, the largest island of the Canaries. We observed lost falconry birds breeding with natural wild falcons, with at least one mixed pair producing fledglings. Only 54.1% of the breeding adults that we studied on the island showed typical Barbary Falcon plumage. Some nest sites were systematically poached, affecting the overall productivity of the population. Our findings suggest that the original Canarian Barbary Falcon population could be suffering from genetic mixing due to the presence of individuals originating from outside the population and from illegal harvest of nestlings. We recommend that local authorities continue to assess the degree of genetic admixture that occurs in this population, modify the current falconry regulations, implement management actions to prevent new escapes, eradicate exotic raptors, and put a stop to illegal nestling harvests.

Inclusion Body Herpesvirus Hepatitis in Captive Falcons in the Middle East: A Review of Clinical and Pathologic Findings.

Inclusion body hepatitis in falcons is caused by a herpesvirus designated Falconid HV-1. This herpesvirus and other herpesviruses affecting birds of prey have not been assigned to a genus and include inclusion body herpesvirus hepatitis in eagles (Accipitrid HV-1) and inclusion body herpesvirus hepatitis in owls (Strigid HV-1). Herpesvirus infections have been diagnosed in both captive and free-living raptors across Europe, North America, and Asia in different species of the family Falconidae. Herpesviruses affecting owls and falcons have been found to be antigenically similar to pigeon herpesvirus (Columbid HV-1) and distinct from other avian herpesviruses. When the herpesvirus isolates from owls, falcons, and pigeons were compared by sequencing a fragment of the herpes viral DNA polymerase gene from those birds naturally infected with the virus, the sequences from these 3 sources were found to be nearly identical. The authors of this study concluded that the Falconid HV-1, Strigid HV-1, and Columbid HV-1 were the same virus. Furthermore, the authors also proposed that the virus therefore be referred to as Columbid HV-1 (CoHV-1), because pigeons may be responsible for the transmission of the virus to birds of prey. Pigeons are often carriers of the virus without showing any clinical signs. It has long been suspected that raptors may contract the infection by the ingestion of infected pigeons. Some studies have suggested that falcons may not contract the infection through the oral route by ingesting carrier pigeons, but through the ocular or nasal route. Inclusion body herpesvirus hepatitis is a frequently diagnosed disease in the captive falcon population used for falconry, racing, and breeding in the Middle East, and it seems to be associated with the extensive use of pigeons for training and as a food item. This paper reviews the clinical and pathological findings in falcons affected by inclusion body herpesvirus hepatitis in the Middle East.

Review of the development of the Peregrine Falcon(Falco peregrinus)population in Hungary between 1997 and 2018

AbstractPeregrine Falcon(Falco peregrinus)populations recovered globally after a dramatic decline experienced between the 1950s and 1980s. The conservation challenge forced the raptor biologist community to co-operate internationally. As a part of the co-operation, four conferences were organised to identify the problem, coordinate conservation efforts including research and to monitor the recovery process of the species’ populations worldwide. The line of conferences started in Madison (WI, USA) in 1965 and was followed by two conferences in Sacramento (CA, USA) and Piotrowo/Poznań (Poland) in 1985 and in 2007, respectively. The latest conference was organised in 2017, in Budapest, where Peregrine experts discussed the latest research and monitoring results. The event provides a good occasion to review the development of the Peregrine population in Hungary. The species became extinct in Hungary as a breeding species in the mid-1960s due to the intensive use of pesticides (DDT) and it returned only in 1997, when the first successful breeding was recorded. In 2018, 72 active eyries were recorded. The Hungarian population is the edge of the Carpathian Peregrine population and the birds represent mostly the nominate subspecies(F. p. peregrinus), but individuals showing typical phenotype of the Mediterranean subspecies(F. p. brookei)were also observed. The northern race ofF. p. calidusalso occurs on migration and in winter. The Hungarian population is sedentary. Natal dispersal of females is biased to males, but in case of both sexes most ring recoveries of adult birds occurred within the Pannonian basin. The increasing Peregrine population expanding to the lowland may cause conservation conflict on medium term by competing with the endangered Saker Falcon(Falco cherrug)for the nest sites. The conservation status of the Peregrine Falcon in Hungary is good in general, but threats may emerge on local scale in some regions. No specific conservation measures are taken, research and monitoring focus on population changes and threats posed on and caused by Peregrines.

Monitoring of Peregrine Falcons in the Ariège Pyrenees and Toulouse, Midi-Pyrénées region, France

Abstract Since the 1980s, the volunteers of the ornithological group of the Nature Midi-Pyrénées association have been monitoring the Peregrine Falcon (Falco peregrinus) population in the Ariège Pyrenees and in the Toulouse agglomeration. The data collected over the last 30 years show stability of the Ariège population: little variation has been observed in brood size, occupation rate of the sites or reproductive success. Only the increasing number of known nesting sites is significant, due to better knowledge of the territory by observers over time. In 2017, the breeding population was estimated to be 24 pairs. Urban monitoring proved the presence of individuals in passage, wintering or resident in Toulouse. Since 2002, downtown Toulouse has been visited by several individuals of both sexes and interactions between males and females have been observed since 2005. Despite the multiplicity of possible eyries or nesting sites in Toulouse, and the massive presence of Peregrine Falcons and dedicated bird watchers, no case of breeding has been reported. In addition to monitoring, measures to protect and support the presence of the species have been put in place. In the Pyrenees, in the light of the growth of human activities near nesting sites, some sites are now subject to official protective measures, coupled with constant vigilance and awareness. In Toulouse, to encourage the breeding of the individuals present, two nesting boxes were installed in 2016, on two buildings frequented by a female and a male. In 2017, a first attempt to reproduce in one of these installations confirmed the value of such developments in urban areas.

Population trends of Peregrine Falcon in Northern Spain – Results of a long-term monitoring project

Abstract We monitored Peregrine Falcon (Falco peregrinus) population in Bizkaia, Northern Spain, during two decades (1998–2017). Our population increased from 34 to 47 territorial pairs, as did other European populations until the first years of the 21st century, and then declined until 34 territorial pairs in 2017. The combination of catastrophic events (Prestige oil spill), increasing rain in winter and spring, and direct and indirect mortality factors significantly affected incubation onset, productivity and population stability, which in turn could impact on the floater population. Rain in February significantly affected incubation onset, which showed a slight positive trend during the last decade. Juvenile females laid 12 days later than adults, and each adult female started incubation in the same dates every year. However, the proportion of juvenile females did not significantly increase as might have been expected. Moreover, productivity was inversely related to incubation onset dates. Rain in April and May also affected productivity, and combined with short term extreme weather events determined a decreasing productivity during the last decade. Moreover, apart from human persecution (which caused 40.30% of the known deaths of Peregrines), we found 18 cases of breeders affected by infectious diseases, also related to weather. The combined effects of these factors, and the low availability of adequate nesting sites, negatively affected (i) territorial populations, (ii) productivity, and (iii) floater population, which in turn also determined territorial population and productivity.

Raptors are still affected by environmental pollutants: Greenlandic Peregrines will not have normal eggshell thickness until 2034

Abstract The DDT-induced effects, eggshell thinning and breeding failure in Peregrine Falcon (Falco peregrinus) populations were reverted with restrictions on the use of the compound from the 1970s, and in most studied populations, the eggshell thickness is back to normal. In Greenland, a previous study of eggshell thinning in Peregrines found that shells had not yet reached pre-DDT levels. In this study, we extend the time series and reinterpret shell thinning data for 196 clutches covering a 45-year time span (1972–2017). There was a significant (P<0.001) increase in the eggshell thickness of 0.23% per year. This corresponds to a change in eggshell thinning from 14.5% to 5.4% in 2017 compared to the pre-DDT mean. With the current rate of change, pre-DDT shell thickness is predicted to be reached around the year 2034. However, a few clutches are still below the critical limit. The relatively slower recovery of the shell thickness in the Greenland population is likely indicative of the slower phasing out of DDT in the Greenlandic Peregrines’ wintering grounds in Latin America. The shell thinning in the Greenlandic population probably never crossed the 17% threshold associated with population declines, contrary to the populations in many other parts of the world.

Influence of the Eagle Owl (Bubo bubo) on the Peregrine Falcon (Falco peregrinus) population in Germany

Abstract In Germany, the Eagle Owl is the only animal species that has a massive impact on the distribution and breeding success of the Peregrine Falcon. Both species compete for the same breeding sites on rocks. In addition, the Peregrine Falcon belongs to the prey spectrum of the Eagle Owl. The Eagle Owl always dominates at places where the two species meet. Since the 1980s, the Eagle Owl has taken over many of the rock face breeding sites of the Peregrine Falcon in Germany. This trend towards the taking-over of Peregrine Falcon nesting sites is ongoing in areas with rocks, as not all regions of Germany have yet been completely colonized by Eagle Owls. Since 1975, the Eagle Owl initially nested on buildings in rural areas, but it is now also colonizing urban areas. Eagle Owls are more and more frequently taking over Peregrine Falcon nest boxes on buildings. The currently growing Peregrine Falcon breeding population on buildings is expected to decline in coming years due to predation by the Eagle Owl, even though these owls do not breed very successfully on buildings and many old and young owls are killed. These statements apply to large parts of Germany. In other areas of Europe, the future usage of buildings as Eagle Owl breeding sites can be expected to have an impact on the Peregrine Falcon populations there. At least eight other Peregrine Falcon breeding sites on buildings and rocks have been taken over by Egyptian Geese (Alopochen aegyptiaca).

Results of eighteen years (2000–2017) monitoring study of an extra-alpine Peregrine Falcon Falco peregrinus population in North-Western Italy

Abstract The Author reports the results of a survey about a breeding extra-alpine Peregrine Falcon population in Cuneo Province, NW Italy. The first reproduction was recorded in 2000, and from that year, the monitoring work localized 16 occupied territories in an area of 1,900 km2 covering the hills and nearby lowland areas. The average distance between breeding territories was of 7.6 km with a density 0.7 pairs/100 km2. During the eighteen years, 89 successful breeding attempts were recorded, 81 of them led to fledging of 206 young. Average breeding success was 2.5 juv/reproducing pairs. The nests are located on bridges (motorway viaducts and rail way bridges) and clay/sandstone cliffs. Preliminary prey analyses showed that pigeons and doves represent the 75% of their diet.

Inter-island Movements of Two Barbary Falcon (Falco peregrinus pelegrinoides) Juveniles in the Canary Islands

We studied the post-fledging movement of two sibling (male and female) juvenile Barbary Falcons (Falco peregrinus pelegrinoides) hatched in Lanzarote (Canary Islands) in 2011 using satellite tracking. Birds were tracked from fledging in May to the end of November, when the signals of both transmitters were lost. During the first 45 d following fledging, both birds behaved similarly and made some flights 3000 km from the nest, probably using a ship as a perch. Because Barbary Falcon populations of the Canary Islands are listed as “threatened” due to anthropogenic threats (e.g. collisions with human-made structures, illegal shooting, nest-robbing, and hybridization with escaped falconry falcons) and little is known about their post-fledging dispersal movements, more studies of such life-history characteristics, using ringing and remote sensing, are urgently needed to develop management actions for their conservation.

Genetic variability in Peregrine Falcon populations of the Western Palaearctic region

Abstract We analysed variation in ten polymorphic microsatellite loci and a portion of cytochrome b gene of mitochondrial DNA in 65 samples from four populations of Peregrine Falcon (Falco peregrinus peregrinus and F. p. brookei) breeding in Northern and Southern Italy, Northern Spain and the Czech Republic to assess genetic diversity in the poorly investigated Western Palearctic region. We added to our cytochrome b sequences a dataset of previously published mtDNA sequences of other populations and subspecies to outline genetic variation in the region on a worldwide basis. Regarding mtDNA we identified 12 haplotypes from our 65 Peregrine Falcon samples, nine of which were new and three already known. The 52% of our samples, including all Italian and Czech specimens, belonged to the previously identified HI haplotype, another 22% of the samples, most of which were from Sicily, showed the new H1 haplotype, while the remaining 26% of the sample partitioned among the other 10 haplotypes. Allelic patterns and genetic structuring of microsatellites were similar to those of other European populations. Genetic differentiation in both mtDNA and microsatellites loci is almost absent and it is not possible to distinguish geographical groups according to taxonomic designation at the subspecies level.

The Danish Peregrine Falcon population: Reestablishment and eggshell thinning

Abstract Denmark being a country with only a few suitable steep nesting cliffs has only harboured a small population of Peregrine Falcons (Falco peregrinus) in historic time. In the previous century, the population gradually declined due to persecution, egg and young collection, and pollution. The last breeding attempt in the 20th century occurred in 1972 in southeastern Denmark. No new breeding attempts were recorded in Denmark until 2001 but since then the population has gradually increased – most rapidly since 2012 – to a peak of 24 territorial pairs in 2018; some of them breeding on man-made structures (nest boxes at bridges and power plants). Here we update the information on the reestablishment of the Peregrine Falcon in Den-mark, including origin and dispersal, reproduction, and eggshell thinning.

Perfluoroalkyl substances (PFASs) and polychlorinated naphthalenes (PCNs) add to the chemical cocktail in peregrine falcon eggs

A suite of perfluoroalkyl substances (PFASs) and polychlorinated naphthalenes (PCNs) were determined in 41 peregrine falcon eggs collected in South Greenland between 1986 and 2014. Median concentrations of perfluorinated sulfonic acids (ΣPFSA) and perfluorinated carboxylic acids (ΣPFCA) were 303 ng/g dry weight (dw) (58 ng/g wet weight, ww) and 100 ng/g dw (19 ng/g ww), respectively, which was comparable to other studies. Perfluorooctane sulfonate (PFOS) accounted for 94% on average of all PFSAs, but did not show a significant time trend. Perfluorohexane sulfonate (PFHxS), perfluoroheptane sulfonate (PFHpS) and perfluorodecane sulfonate (PFDS) showed non-linear decreases over the study period, while some long-chain PFCAs increased significantly. The PCN profile was dominated by the penta-, hexa- and tetrachlorinated congeners CN-52/60, CN-66/67 and CN-42. CN-54, an indicator of combustion, accounted for 2.4% of ΣPCN on average. All PCN congeners showed a decreasing tendency, which was significant for lipid-normalized concentrations of CN-53, CN-54 and CN-63. The ΣPCN median concentration was 21 ng/g lipid weight, which is in the high end of concentrations reported for bird eggs. The PCN and PFAS concentrations add to an already high contaminant burden and a complex chemical cocktail in the peregrine falcon population in Greenland, mainly reflecting contaminant exposure during migration and winter stays in Central and South America.

New insights into the phylogenetics and population structure of the prairie falcon (Falco mexicanus)

BackgroundManagement requires a robust understanding of between- and within-species genetic variability, however such data are still lacking in many species. For example, although multiple population genetics studies of the peregrine falcon (Falco peregrinus) have been conducted, no similar studies have been done of the closely-related prairie falcon (F. mexicanus) and it is unclear how much genetic variation and population structure exists across the species’ range. Furthermore, the phylogenetic relationship of F. mexicanus relative to other falcon species is contested. We utilized a genomics approach (i.e., genome sequencing and assembly followed by single nucleotide polymorphism genotyping) to rapidly address these gaps in knowledge.ResultsWe sequenced the genome of a single female prairie falcon and generated a 1.17 Gb (gigabases) draft genome assembly. We generated maximum likelihood phylogenetic trees using complete mitochondrial genomes as well as nuclear protein-coding genes. This process provided evidence that F. mexicanus is an outgroup to the clade that includes the peregrine falcon and members of the subgenus Hierofalco. We annotated > 16,000 genes and almost 600,000 high-quality single nucleotide polymorphisms (SNPs) in the nuclear genome, providing the raw material for a SNP assay design featuring > 140 gene-associated markers and a molecular-sexing marker. We subsequently genotyped ~ 100 individuals from California (including the San Francisco East Bay Area, Pinnacles National Park and the Mojave Desert) and Idaho (Snake River Birds of Prey National Conservation Area). We tested for population structure and found evidence that individuals sampled in California and Idaho represent a single panmictic population.ConclusionsOur study illustrates how genomic resources can rapidly shed light on genetic variability in understudied species and resolve phylogenetic relationships. Furthermore, we found evidence of a single, randomly mating population of prairie falcons across our sampling locations. Prairie falcons are highly mobile and relatively rare long-distance dispersal events may promote gene flow throughout the range. As such, California’s prairie falcons might be managed as a single population, indicating that management actions undertaken to benefit the species at the local level have the potential to influence the species as a whole.