Journey through the dangerous summer escapade of a common bird residing in the Northwest
Swainson's Thrush: A Long-Distance Migrant Facing Challenges
The Swainson's thrush, a common bird in the Pacific Northwest during the summer breeding season, embarks on a remarkable journey each year to overwinter in Central and South America. This long-distance migrant faces significant threats from habitat loss and climate change throughout its migratory cycle.
During migration, Swainson's thrushes face challenges crossing ecological barriers such as the Gulf of Mexico and mountainous regions. These journeys require critical stopover habitats for rest and refueling, but development, logging, agriculture, and climate change pose risks to these crucial sites.
In their overwintering grounds, deforestation reduces available habitat, while climate change impacts include altered migration timing and reduced food availability. These factors can negatively affect the Swainson's thrush's reproductive success and population stability.
Older forests play a vital role in supporting breeding bird populations. They offer more food and a greater variety, as well as places to escape the heat. However, clear-cutting of forests in the Pacific Northwest limits the availability of the microclimate refuge provided by older forests.
A 2022 paper found that the type of forest that remains matters, with simplified, younger forest not being equivalent habitat to older forests. Old-growth forests at the H.J. Andrews Experimental Forest provide refuge for birds in a warming world, helping slow the effects of climate warming on some breeding bird populations.
In an effort to help migratory birds, a former farm in San Vito, Costa Rica was purchased in 2019 to replant a forest, including for the Swainson's thrush. The research station at Finca Cantaros in Costa Rica is pass-through territory for Swainson's thrushes during migration. Volunteers at Finca Cantaros help plant and care for the forest growing on what was once cattle pasture.
The goal of the Women Committed to the Earth program is not only to grow a forest, but also to foster a sense of conservation among the volunteers and a bond between these local women, their children, and the place. The program, sponsored by Finca Cantaros, brings local women of all ages to the forest for hiking, art-making, and bonding on a weekly outing.
Birds tagged with radio transmitters have been detected on the Motus Wildlife Tracking System station at Finca Cantaros and in B.C., in a tracking program led by Birds Canada. While the Swainson's thrush is known as the "gray mouse" in Central America, where it does not make its signature song and is regarded as a very common, ordinary bird, the species faces perils during its migration due to changes throughout its range.
In summary, Swainson's thrush populations are vulnerable to the combined pressures of habitat loss and climate change throughout their migratory cycle, from overwintering grounds through migration to breeding sites. Efforts to conserve and restore habitats, such as the work being done at Finca Cantaros, are crucial to support these remarkable long-distance migrants.
[1] Bird Studies Canada [2] Motus Wildlife Tracking System
- The Swainson's thrush, a bird native to the Seattle area during the summer, is facing challenges due to politics surrounding habitat preservation and climate-change policies.
- In Bellevue, the University of Washington is conducting research on environmental science and climate change, aiming to understand how these factors impact the Swainson's thrush's migration.
- As part of their education-and-self-development programs, students can participate in learning about the Swainson's thrush and its migration, and contribute to data collection using the Motus Wildlife Tracking System.
- Local environmental groups in Seattle are advocating for stricter regulations on logging and development, to ensure the preservation of critical stopover habitats for the Swainson's thrush during migration.
- Citizen science initiatives are encouraging people in the Pacific Northwest to contribute to the monitoring of Swainson's thrush populations, providing valuable data for conservation efforts.
- In the realm of policy, there is a growing need for government investment in environmental-science research and the preservation of critical habitats for the Swainson's thrush and other migratory birds.
