The Willow Flycatcher is present in patches of wetland habitat in the Rocky Mountains and Foothills of Alberta. Due to lack of study, population size and trends have not been determined accurately. Population size is thought to be low and BBS data indicates a decline in numbers. The possible limiting factors for the Willow Flycatcher include: loss of habitat from human disturbance and cattle grazing; productivity losses from Brown-headed Cowbird parasitism; and competition with Alder Flycatchers.
The lack of study about the Willow Flycatcher in Alberta is currently the greatest weakness in working towards a management plan. Several questions should be answered with respect to Alberta’s population of Willow Flycatchers. The Willow Flycatcher is not endangered as a species but western populations of this species are at risk. The Alberta population constitutes a tiny fraction of the continental population. From a biological perspective, it is significant that the most northerly populations of this species are in Alberta and British Columbia and that no assessment of the genetic distinctness of northern populations has been made. Volunteer help in documenting other potential breeding area for this species would be useful if supporting identification aids (primarily song recordings) are provided. Population trends, nest success and survivorship would be necessary to examine the success of the Willows breeding in Alberta. Although the Willow Flycatcher does not appear to be at risk in the province, the most probable area of concern would be that of human disturbance. The relative ease with which significant amounts of Willow Flycatcher habitat could be unknowingly destroyed is significant. Any management plans drafted would have to consider this. Based on data from British Columbia and the southwestern United States, it would be advisable to study the effects of cattle grazing and Brown-headed Cowbird parasitism on Willow Flycatchers in Alberta, because this is a topic of concern elsewhere.