Protected Species in Pennsylvania: Yellow-bellied Flycatcher

Introduction

Factors such as urban sprawl and development has pushed many species to live in smaller and smaller parcels. One species that is declining in Pennsylvania, due to urban sprawl, is the Yellow-bellied flycatcher (Empidonax flaviventris). The public and landowners can help protect this endangered species by supporting research efforts for recovery plan and managing their properties to provide better habitat.

What is a Yellow-bellied Flycatcher?

The yellow-bellied flycatcher is a migratory bird species that spends its summers in the northern United States and Canada and its winters in Central America. The bird is an olive-green color with a distinct yellow breast, as its name suggests, and feeds primarily on insects. The species travels north in late spring in search of swampy conifer forests at high elevations, usually preferring to nest and raise their young in forests that contain spruce. The yellow-bellied flycatcher is only at its nesting sites for a short time and migrates south again by late August. As soon as the juveniles are capable of surviving on their own, they begin their flight and are followed shortly after by their young.

Why are they Endangered in Pennsylvania?

Since the 1970’s the Yellow-bellied flycatcher has increased in areas such as Canada, but populations in Pennsylvania have been steadily decreasing and local groups may disappear in the next several years if immediate action is not taken. The Yellow-bellied flycatcher was moved from the status of threatened to state endangered in 2005. It is believed that the main cause of population declines in Pennsylvania is due to habitat loss and climate change. The yellow-bellied flycatcher primarily lives and breeds in the high elevation bogs in northeastern Pennsylvania. Much of this area has undergone intense development over the recent years and this has led experts to suspect that in response these birds are leaving the state. Climate change is also expected to impact the species by altering the composition of high elevation forests and pushing most species north. Protecting spruce bogs in PA can help protect the southernmost range of the species, which may be important for providing more habitat options during migration.

Who is involved in protecting this species?

The Pennsylvania Game Commission is responsible for addressing the conservation of the yellow-bellied flycatcher in Pennsylvania. The recent Wildlife Action Plan recommends further investigation of yellow-bellied flycatcher nesting sites to get a better estimate of the number of birds nesting in the state. The US Fish and Wildlife Service is also involved because the yellow-bellied flycatcher is listed as a migratory bird of concern which makes it protected under the Migratory Bird Treaty Act of 1918. The Migratory Bird Treaty Act prohibits the taking of protected migratory bird species without authorization by the Department of Interior US Fish and Wildlife Service. Having the US Fish and Wildlife Service involved in the conservation of this species is essential because it allows the species to be managed on a global scale rather than a local scale. This is important for the yellow-bellied flycatcher because it nests and winters in completely different states.

Why should I care?

To some, the Yellow-bellied flycatcher may be just another bird nobody knows about, but like every other species in an ecosystem it has an important role. Firstly, it adds to the biodiversity in an ecosystem, and the greater the biodiversity, the healthier an ecosystem usually is. The yellow-bellied flycatcher is not the only species that uses high elevation spruce bogs to nest either. Other threatened and endangered species such as the blackpoll warbler also use this type of habitat. So, if habitat loss is the driving factor causing the yellow-bellied flycatcher’s decline, it could be greatly reducing the biodiversity in Pennsylvania as many other species could be lost in the same places for the same reasons. Plus, with the yellow-bellied flycatcher being an insectivore, it takes care of some of those pesky insects that could bite and bother one on a summer evening. Not only is it important to protect this endangered species, but its endangerment is thought to be linked to other environmental issues such as climate change. So, by caring and working to save this species in Pennsylvania, it can also help address other environmental and conservation issues.

What can be done to help?

This species is not well-known and has only recently become a species of concern in the state, so more research is needed to plan for recovery. Unfortunately, their seclusive nesting sites makes it hard for scientists to easily study its habits and get accurate population estimates. Research is also needed to better understand specific drivers of species decline. Even though it is thought to be habitat loss and climate change, there has been no concrete research to either confirm or deny these theories. 

One thing we can all do to help is to simply spread the word about the Yellow-bellied flycatcher. Let researchers, government agencies, and conservation groups know that this species is important to us, an important part of the ecosystem and that it needs help. Forest owners can also help by protecting the yellow-bellied flycatcher’s preferred nesting habitat. The Natural Heritage website can help you determine if your property is within the range and has the habitat requirements for this species. Lastly, we can try to help by mitigating climate change impacts by using renewable energy instead of coal or oil when possible. Working together in this way can help create larger changes for this species over time.

Student Authors

This article was written by undergraduate students as part of a class project in the Department of Ecosystem Science and Management at Penn State.

References

Brauning, D. W. (n.d.). 2015-2025 Pennsylvania Wildlife Action Plan. Retrieved March 19, 2021.

Felbaum, M. (2007, August 22). Yellow-bellied Flycatcher. 

Fergus, Chuck. "Flycatchers." Pennsylvania Game Commission.

Gross, D. (2014, August 19). Yellow-Bellied flycatcher. 

McClarren, C. (2015, November 30). Yellow-bellied flycatcher "empidonax flaviventris". Retrieved February 6, 2021.

Raelston, J., King, D. I., Deluca, W. V., Niemi, G. J., Glennon, M. J., Scarl, J. C., & Lambert, J. D. (2015). Analysis of Combined Data Sets Yields Trend Estimates for Vulnerable Spruce-fir Birds in the Northern United States. Biological Conservation, 187, 270–278. doi.org/10.1016/j.biocon.2015.04.029

Spiller, K. J., & Dettmers, R. (2019). Evidence for Multiple Drivers of Aerial Insectivore Declines in North America. The Condor: Ornithological Applications, 121, 1–13. doi.org/DOI: 10.1093/condor/duz010

Yellow-bellied Flycatcher. State of Mountain Birds. (2021).