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Landscape associations:

[BCR]

[Ecoprov.]

[BEC zones]

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Elevation range: 0 - 1945 m Conserv. status: Not at risk Global importance of B.C. population: 6

Number of squares Confirmed Probable Possible Point counts 69 180 572 325 Long-term BBS trends Region Years Trend (conf. interv.) Reliab. Brit. Col. 1970 - 2012 -2.5 (-5.58 - 0.266) Medium Canada 1970 - 2012 -4.59 (-5.98 - -3.3) High

Characteristics and Range The massive, seed-cracking bill and striking gold, black and white body of the Evening Grosbeak are difficult for observers to miss. The Evening Grosbeak breeds in southern boreal and northern temperate coniferous and deciduous forests across North America and southward in western montane forests (Gillihan and Byers 2001). It is resident throughout its breeding range, but often abandons the northernmost portions during winter when it is found south of the breeding range in eastern temperate forests. The Evening Grosbeak is well known for fall and winter irruptions and wanderings in response to changes in food supply (Gillihan and Byers 2001).

Distribution, Abundance, and Habitat The Evening Grosbeak breeds mainly throughout the southern and central interior of British Columbia. Campbell et al. (2001) noted that the breeding distribution in British Columbia was poorly known. The Atlas systematic survey effort has expanded the confirmed and probable breeding distribution throughout the province since The Birds of British Columbia was published in 2001, providing a more detailed picture for this nomadic bird. The Evening Grosbeak is distributed across a wide altitudinal range, but most breeding occurs at mid-elevations.

The most extensive area of high Probability of Observation is in the Southern Interior Ecoprovince, spilling into neighbouring portions of the Coast and Mountains, Southern Interior Mountains and Central Interior ecoprovinces. Atlas point counts show highest abundance between 1,000 and 1,250 m, corresponding with the mid-elevation plateaus in this area, and in the Interior Douglas-fir and Montane Spruce biogeoclimatic zones that dominate those plateaus.

Coniferous and mixed wood forests are preferred for nesting. Breeding is frequently associated with outbreaks of forest-defoliating insects such as spruce budworm; therefore, local abundance can vary greatly through time and space.

Conservation and Recommendations Across Canada, Evening Grosbeak populations have shown a large decrease since 1970 (Environment Canada 2011). The causes of the decline are not well understood, but probably stem from multiple factors including large-scale forestry operations, disease, and reduced food availability due to fewer forest insect infestations, especially spruce budworm. It may be that the recent decline is largely a return to "normal" levels as budworm outbreaks have declined. Breeding Bird Survey data suggest that the decline may be less steep in British Columbia than more eastern regions; continued monitoring is important to clarify whether this is the case. Collisions with moving cars are a common source of mortality of Evening Grosbeaks in winter because they are attracted to roads by sand and salt laid for de-icing, especially when the ground is covered by snow. At least 2,000 adults were found dead in 1980 along the highway through Manning Park, with many more dead off-road (Smith 1981).

Art Martell

Recommended citation: Martell, A. 2015. Evening Grosbeak in Davidson, P.J.A., R.J. Cannings, A.R. Couturier, D. Lepage, and C.M. Di Corrado (eds.). The Atlas of the Breeding Birds of British Columbia, 2008-2012. Bird Studies Canada. Delta, B.C. http://www.birdatlas.bc.ca/accounts/speciesaccount.jsp?sp=EVGR&lang=en [09 Oct 2024]