Cliff Faces
For the prairie falcon, the most suitable locations that they like to nest in are cliff faces. In a study done by Runde, prairie falcons “nest almost exclusively on rock cliffs. Nest cliffs used vary widely in height, location and aspect. Yet, in the studies examined, Prairie Falcons demonstrated some consistent patterns in their use of eyries (nests of birds of prey). Mean eyrie and cliff heights were strongly correlated and distributions of eyrie and cliff aspects were similar” (Runde 2024). This tells us that prairie falcons prefer nesting in cliff faces as they provide protection from the elements. To get information on cliff faces, I took DEM data from the BC catalog and turned it into TIN data. Using that TIN data, we can get the slope, which will tell us where cliff faces are located.
Elevation
Elevation is another important factor for where prairie falcons nest. According to Runde, “by nesting in the upper reaches of vertical cliffs, prairie falcons should be safe from mammalian predators. Such a location also provides a commanding view of the territory and of potential prey or predators” (Runde 2024). Another source says, “In British Columbia, nesting has been documented from 450 to 900 m elevation” (Campbell 1990). This tells us that although prairie falcons like to live in higher elevations, they can’t exceed a certain point due to temperature. The most suitable elevation would be between 450 to 900 m. Using the DEM data that I gathered from the BC catalog, I was able to see the elevations of different areas.
Aspect
The aspect is not as well-known for nesting as elevation and slope but might be crucial to the development of prairie falcons. According to the article by Runde, “mean eyrie aspects averaged 161.2˚ (r = 0.24); mean cliff aspects averaged 158.3˚ (r = 0.19)” (Runde 2024). They prefer cliffs that are south-facing because southerly exposure can help with extreme temperatures during incubation and brooding. “Solar heating of nest scrapes may lessen the energy requirements of incubating and brooding falcons” (Runde 2024).
Grasslands
Grassland is needed to help sustain the prairie falcon population. During the breeding season, Prairie Falcons usually hunt over grasslands and sagebrush habitats near the nest. Prairie Falcons require ample, accessible prey near the nest site. Grasslands are able to provide just that. Open areas with relatively low-density, patchy vegetation can’t allow prey to hide, so prairie falcons have ample opportunities to catch prey.