Vaux’s Swift (Chaetura vauxi) Potential Occurrence: Nesting Likely To Occur




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Aves (Birds): Apodiformes,Apodidae

Vaux’s Swift (Chaetura vauxi)

Potential Occurrence: Nesting Likely To Occur



Status: (Nesting)

Federal: none

State: SSC

Other: G5 S3



Species Description: Small, short-tailed swift with long, narrow wings, a blackish body and a whitish throat. The body length is 4.75 inches and the wingspan is 12 inches. In flight, Vaux’s Swift resembles a “cigar with wings” (Sibley 2000).

D
Photo: © Peter LaTourrette 2008
istribution:
Vaux’s Swift is a migratory bird whose breeding range extends from southern British Columbia to northern California and whose winter range is in central Mexico south to Venezuela (Hammerstien 1994). It is a summer resident of northern California in the narrow redwood forested coastal zone from Del Norte to Santa Cruz counties (Sterling 1996).

Life History & Threats: Nests are built of sticks and small twigs adhered with sticky saliva, inside vertically-oriented cavities such as hollow snags, burned out trees, and chimneys (Bull 2007). The clutch size varies from 3-7 eggs, which are incubated by both parents, and hatch after 18-20 days. Nestlings can leave the nest after 20-21 days, and will perch on the interior wall the nest is built on, taking up to a week to fly freely. (Hammerstein 1994)

Heavy logging of mature and old-growth forest in British Columbia, the Pacific Northwest of the United States, and coastal redwoods in the latter part of the 20th century have in all likelihood reduced the species' habitat significantly. Steep population declines are evident in the Pacific Northwest over the past twenty years. … Classified as a "species of special concern" in California in 1994. Considered a priority species for conservation in the Partners in Flight planning process for the southern Pacific rainforests physiographic region. (From Paige 2000)



Habitat & Habitat Associations:

Roost and nest in cavities with a vertical entry, such as hollow trees and chimneys (Sibley 2000). The range for diameter at breast height of roost trees was 47-100 cm (Bull 2007).

In North America, prefers late seral stages of coniferous and mixed deciduous/coniferous forests; more abundant in old-growth forests than in younger stands. The multi-layered broken overstory of old-growth forests may also provide easier access to aerial insects than closed, continuous canopies of younger forests. In northern California, uses Douglas-fir forests but highest densities are in coastal redwood (Sequoia sempervirens) habitats (From Hammerson 1994)

Vegetation Types: Redwood or Douglas-fir forests (Hammerson 1994; Sterling 2006)

Other Special Habitat Features: Extensive use of hollow snags and burned-out trees for nesting

Conceptual Basis for GIS Model Development: Potential habitat was mapped as:


  • Coniferous forest (i.e., redwood-Douglas fir or Douglas-fir forest vegetation types)

  • Possible best habitat was mapped as areas in the above vegetation types with:

    • multi-story canopy, and

    • trees > 11” (28 cm) DBH. Note that Vaux Swifts are found in forested areas with trees with a DBH of 47-100 cm. The two largest size classes in the Study Area for DBH are 28 – 61 cm (11 -24 in) and > 61 cm (> 24 in). We include both these size classes to ensure that we map all potential habitats for this species.

Potential Occurrence in the Galbreath Wildlands Preserve: Protection status for Vaux’s Swift applies to nesting individuals.

Habitat: This species nests in snags and burned out trees in coniferous forests. Nesting habitat on the Preserve may be moderate to good quality (Figure 67). Coniferous forests with large trees is abundant throughout the Preserve, and snags, the preferred nesting substrate are relatively common. Logging on the Galbreath Wildlands Preserve was discontinued in 2000 and large snags can be seen scattered throughout the Preserve. Multi-story habitats preferred by these species while feeding their young are not as abundant but are found at scattered locations in the Preserve.

Nearest Occurrence:

Documented Occurrences in the Galbreath Wildlands Preserve: This species has not been documented in the Study Area. To our knowledge, no surveys have been conducted.

Nearest Occurrence to the Galbreath Wildlands Preserve: The Vaux’s Swift has not been reported to occur in USGS quads adjacent to the Study Area. However, its breeding range is known to occur in areas to the north and south of the Preserve

Summary: Nesting individuals are “Likely to Occur” in the Galbreath Wildlands Preserve. Nesting habitat quality is moderate to good and relatively abundant, and the species widespread, mobile and known to nest in this region of the California coast.

References

Bull EL, Collins CT. 2007. Vaux's Swift (Chaetura vauxi), The Birds of North America Online (A. Poole, Ed.). Ithaca: Cornell Lab of Ornithology; Retrieved from the Birds of North America Online: . Accessed 2010 Jul 13.

Hammerstien G. 1994 Mar 17. Ecology and Life History. Comprehensive Report Species- Chaetura vauxi. NatureServe. 2009. From NatureServe Explorer: An online encyclopedia of life [web application]. Version 7.1. NatureServe, Arlington, Virginia. . Accessed 2010 Jul 12

Paige C. 2000 Nov 10. Management Summary. Comprehensive Report Species- Chaetura vauxi. NatureServe. 2009. From NatureServe Explorer: An online encyclopedia of life [web application]. Version 7.1. NatureServe, Arlington, Virginia. . Accessed 2010 Jul 13

Sibley DA. 2000. The Sibley Guide to Birds. New York: Alfred A Knopf. p 290.

Sterling J. and Paton PWC. 1996. Breeding distribution of Vaux's Swift in California. Western Birds 27:30-40.



Species Account Description: Kandis Gilmore & Emily Harvey


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