Prairie Falcon (Falco Mexicanus) Management Indicator Species Assessment Ochoco National Forest

Prairie Falcon (Falco mexicanus) Management Indicator Species Assessment Ochoco National Forest

I. Introduction

The prairie falcon was chosen as a terrestrial management indicator species (MIS) for cliff, talus or cave habitat (LRMP 4-245).

II. Life History

Species Distribution –

This species breeds from c. British Columbia east to N. Dakota, south to Baja California and Texas. It winters over much of its breeding range south to Mexico (Marshall 2003).

They breed throughout the open country east of the Cascades wherever cliffs and outcrops provide opportunities for nesting (SWJ) (Marshall 2003). On the Ochoco National Forest, including Crooked River National Grassland, there are records for 12 nesting territories. Additional nesting territories are known from private lands within five miles of the Forest boundary. Of those on the Forest, only 4 occur in Crook County. The majority of the rest are associated with extensive rimrock habitat present in Jefferson County.

Habitat Characteristics –

Prairie Falcons are most common in rimrock country, where they nest, but may travel great distances in search of prey (Marshall 2003, Birds of Oregon). A combination of rimrock or other outcrops and adjacent open country provides ideal breeding habitat. Cliffs need not be large. Denton (1979) found 59% of nest on cliffs less than 100 ft, some as low as 15 ft. The principal requirement is that the nest site be sheltered from above (Bent 1938, Webster 1976). This appears to reflect a need for shade and possibly protection from predators (Marshall 2003).

Grasslands are the preferred habitat although they also occur in less-productive areas dominated by sagebrush. The principal requirement for foraging appears to be low and sparse vegetation that accommodates their foraging style. Prey most often consists of small mammals, usually ground squirrels (Denton 1976, Haak 1982b).

Threats to the Species

As predators, prairie falcons may be sensitive to certain chemicals in the environment, but since small herbivorous mammals are their primary food source they are not as sensitive as raptors that feed on birds that feed on insects exposed to agricultural pesticides (like the peregrine falcon). This species could be affected by incidental human disturbance especially in developed areas or locations with high recreational use early in the nesting season, or by sudden approaches by low altitude aircraft, though these threats were not listed specifically for this species in Marshall (2003).

III. Conservation Status –

The conservation status of a species is an indicator of the likelihood of that species continuing to survive either in the present day or the future. Many factors are taken into account when assessing the conservation status of a species: not simply the number remaining, but the overall increase or decrease in the population over time, breeding success rates, known threats, and others.

The conservation status of the golden eagle was identified at the global, national, and state of Oregon geographical areas by NatureServe; by listing status from Federal and State Threatened and Endangered Species lists and Sensitive Species lists; by the U.S. Fish and Wildlife Service Birds of Conservation Concern; by the Oregon Conservation Strategy; and by the Partners in Flight bird conservation strategy - Conservation Strategy for Landbirds in the Northern Rocky Mountains of Oregon and Washington.

NatureServe is a non-profit organization based in Arlington, Virginia that provides scientific information about rare and endangered species and threatened ecosystems. The information provided is based on biological inventories or natural heritage programs that operate in all 50 U.S. states, Canada, Latin America and Caribbean. NatureServe information and products are available to conservation groups, government agencies, academia, corporations, and the public.

The U.S. Fish and Wildlife Service maintain a list of Birds of Conservation Concern. Birds of Conservation Concern are species, subspecies, and populations of all migratory nongame birds that, without additional conservation actions, are likely to become candidates for listing under the Endangered Species Act (ESA) of 1973. They represent species that have the highest conservation priorities in the United States, including island "territories" in the Pacific and Caribbean.

The Oregon Conservation Strategy (Oregon Department of Fish and Wildlife 2006) identified strategy habitats and strategy species by conservation region (i.e. Blue Mountains eco-region).

The Partners in Flight bird conservation plans identify priority habitats and species (focal species) that represent priority habitats within bird conservation regions (BCR). The Blue Mountains and WWNF are within the Northern Rockies BCR (BCR 10) which is addressed by the Conservation Strategy for Landbirds in the Northern Rocky Mountains of Eastern Oregon and Washington.

Table 5. Conservation Status of the Golden Eagle. NatureServe Status Federal Status State Status Other Global National Status State Status Federally Regional USFWS Threat- ODFW Oregon Conservation Status Listed, Forester’s Birds of ened, Sensitive Conservation Strategy for Proposed, Sensitive Conserv Endang- Species Strategy Landbirds in Candidate, Species ation ered, and List the Northern Delisted Concern Candidate (2008) Rocky Species and Fish and Mountains of Species of Wildlife Oregon and Concern Species in Washington Oregon *G5— N5B,N5N-- S4-- Not listed – Not listed. Yes Not listed. **Vulner Not a Not a focal Secure Species of -able Strategy species. – Wide- Secure- Apparen concern Species in spread, breeding, tly the Blue abunda Secure- Secure Mountains nt, Eco-region. secure nonbreedin g

* NatureServe conservation status ranks are based on a one to five scale, ranging from critically imperiled (G1) to demonstrably secure (G5). Status is assessed and documented at three distinct geographic scales-global (G), national (N), and state/province (S). The numbers have the following meaning:

1 = critically imperiled 2 = imperiled 3 = vulnerable 4 = apparently secure 5 = secure.

**The Oregon Department of Fish and Wildlife Sensitive Species List status of Vulnerable signifies that the species are facing one or more threats to their populations and/or habitats. Vulnerable species are not currently imperiled with extirpation from a specific geographic area or the state but could become so with continued or increased threats to populations and/or habitats.

Prairie falcons are not listed as Threatened, Endangered or Sensitive Species. They are listed as a Bird of Conservation Concern by the USFWS, though they are listed as secure globally and nationally, and as apparently secure in the State of Oregon. They are not listed as a Strategy Species for the Blue Mountains Ecoregion in ODFW’s Oregon Conservation Strategy, nor are they listed as a focal species in the Landbird Conservation Strategy for the Blue Mountains (Partners in Flight).

IV. Population Trend –

This species occurs in low density and exhibits wide-ranging habits (Marshall, 2003). Breeding densities of 3.9-8.0 pairs/100 square miles Wasco and Wheeler counties (Janes 1975). Lardy (1980) found higher

3 average densities in Malheur Co. (9.8-14.0/100sq.mi.). Populations, including those in Oregon, appear to be stable (White 1994).

V. Habitat Analysis –

A forest-level analysis was conducted in 2011 using updated GIS data on rock features. The output from this analysis reflects the majority of rock features with potential nesting habitat. Rock features identified in the GIS data are those that are of sufficient size to be detected from aerial photographs. The rock categories included in estimating potential nesting habitat for this species included the following: rimrock, rock, rock/limestone, rocky knob, talus, talus/rocky knob, talus/rimrock. The GIS data layer is estimated to be 80% accurate in detecting rock features with cliff faces that have any potential as nesting sites. Some small cliffs may have been overlooked in the aerial photo interpretation, and some rock features identified as potentially having cliff habitat, may not be suitable for nesting sites. However, this data is expected to be representative of the majority of suitable nesting substrate and of sufficient accuracy for a comparison of potential rock habitat within the project area and across the landscape at a forest-wide scale. From this analysis it was estimated that at the forest level there are approximately 18,838 acres of potential cliff nesting habitat (65 acres within the project area). There are a total of 34 watersheds (5th field HUC) on Ochoco National Forest. Potential cliff nesting habitat for is distributed within all 34 of these watersheds, though some watersheds (Crooked River Grassland, Headwaters Deschutes River, Lake Billy Chinook, Lower Metolius River and Willow Creek) have substantially more cliff habitat than other watersheds across the Forest.