The most reliable survey for Olive-sided Flycatchers is the Breeding Bird Survey (BBS), which provides good coverage of the species' breeding population. Results indicate an approximately 70% decrease in abundance in Canada since about 1970 though, with the exception of 2016, the magnitude of decrease has lessened in recent years. The decline is consistent across the regions for which reliable information is available, ranging from a 30% to almost 90% loss in numbers. BBS results from throughout North America indicate that the continental population has also experienced a large decrease. The Olive-sided Flycatcher is below the lowest acceptable level relative to its national population goal (see BBS Canada graph below). This goal is consistent with the Recovery Strategy's long-term objective to ensure a positive trend in the population (Environment Canada 2016a).
Additional information on: Breeding Bird Survey (BBS) - Canadian analysis
