Population status

White-crowned Sparrow
(Zonotrichia leucophrys)

The best source of data for assessing the status of the White-crowned Sparrow in Canada is the Breeding Bird Survey (BBS), which suggests a decrease of about 30% since about 1970. However, BBS data are mostly limited to western parts of the species’ range in Canada, covering only about 35% of the breeding population. In addition, the BBS results do not have strong precision. The continental results of the Christmas Bird Count (CBC) cover a large portion of the wintering range of the White-crowned Sparrow, but include both birds that breed in Canada (approximately 60% of continental population) and the United States (approximately 40%). In contrast to BBS, results of the CBC suggest that continental wintering populations have increased by about 34% since about 1970. Given that BBS is considered the better data source, the White-crowned Sparrow is considered to have shown a moderate decrease in population relative to about 1970, but this assessment has low reliability due to conflicting trends between surveys.

 

Breeding Bird Survey (BBS) - Canadian analysis

Additional information on: Breeding Bird Survey (BBS) - Canadian analysis

Table 1: Population trends by geographic area
Geographic areaTime Period Table 1 - footnote 1 Annual trend Table 1 - footnote 2 Intervals Table 1 - footnote3
LowerUpper
Canada Select to view graph of the geographic area: Canada 1973-2012; Breeding Bird Survey (BBS) - Canadian analysis1973-2012-0.9-4.71.8
 

Picture of logo Christmas Bird Count (CBC)

Additional information on: Christmas Bird Count (CBC)

Table 2: Population trends by geographic area
Geographic areaTime PeriodAnnual trend Table 2 - footnote 1 Limits
LowerUpper
North America1965-20121.10.41.9
 

References