Population status

Eastern Phoebe
(Sayornis phoebe)

The Breeding Bird Survey (BBS) covers over half the Canadian breeding population of the Eastern Phoebe and is the most reliable source of information on population change. The population has fluctuated substantially over time with an overall 24% decrease in numbers since the early 1970s. This magnitude of decrease is on border between what is considered "little overall change" and a moderate decrease. The graph of annual indices demonstrates that numbers increased in the early 1970s, then dropped sharply in the later part of that decade, apparently a result of severe winter weather (Weeks 2011). Since then the population has remained at a relatively similar level to that of the early 1970s. Regional trends vary from a decrease in the Northern Rockies Bird Conservation Regions (BCRs) to increasing or stable populations elsewhere (all BCRs with reasonably reliable results are displayed below). Because the population fluctuated so widely during the 1970s, the national goal for Eastern Phoebe is based on the average abundance over the first 10 years of the BBS (rather than the first 5 years as for most other species) to better represent its early population level. The species is considered below the lowest acceptable level relative to its national population goal. In contrast, the continental population has increased by about 38% since 1970, suggesting the Eastern Phoebe is faring well in the United States.

 

Population goal and acceptable levels of variation

Species/groupGoalLower levelUpper level
Eastern PhoebeMean abundance (first 10 years of survey)Goal minus 25% Not applicable

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 Limits
LowerUpper
Canada Select to view graph of the geographic area: Canada 1970-2016; Breeding Bird Survey (BBS) - Canadian analysis1970-2016-0.6-1.80.4
Canada Select to view graph of the geographic area: Canada 2006-2016; Breeding Bird Survey (BBS) - Canadian analysis2006-2016-1.5-5.22.1
Boreal Taiga Plains Select to view graph of the geographic area: Boreal Taiga Plains 1970-2016; Breeding Bird Survey (BBS) - Canadian analysis1970-2016-1.7-3.30
Prairie Potholes Select to view graph of the geographic area: Prairie Potholes 1970-2016; Breeding Bird Survey (BBS) - Canadian analysis1970-2016-0.2-1.41.2
Boreal Hardwood Transition Select to view graph of the geographic area: Boreal Hardwood Transition 1970-2016; Breeding Bird Survey (BBS) - Canadian analysis1970-20160.701.4
Lower Great Lakes / St. Lawrence Plain Select to view graph of the geographic area: Lower Great Lakes / St. Lawrence Plain 1970-2016; Breeding Bird Survey (BBS) - Canadian analysis1970-20160.5-0.21.2
Atlantic Northern Forest Select to view graph of the geographic area: Atlantic Northern Forest 1970-2016; Breeding Bird Survey (BBS) - Canadian analysis1970-20161-0.32.1
North America Select to view graph of the geographic area: North America 1970-2016; Breeding Bird Survey (BBS) - Canadian analysis1970-20160.70.31
 

References