Painted Bunting Migration Patterns
By Tyler Petruccelli, Fall Conservation Intern
The vibrant plumage of the male Painted Bunting
One of the most beautiful species of bird found on Bald Head Island is the Painted Bunting (Passerina cerris), a small passerine species in the cardinal family. Adult males are easily identifiable by their vibrant and multicolored plumage, boasting blue, green, and red feathers. Females and juveniles are not as colorful as the males, ranging from dull olive to bright green in color. They feed mainly on seeds, and are common visitors to bird feeders. Painted Buntings often find habitat in scrub communities and along the edges of maritime hammocks, making Bald Head Island an ideal home for these birds. Their population on the island is most abundant during the middle of summer, but it is possible to see them anytime between April and October.
Painted Buntings are a fairly common songbird species throughout the southern regions of the United States. They have two geographically separated breeding populations: one in the south-central US and one in the southeast along the Atlantic Coast. Here on Bald Head Island, we represent the northernmost extent of the coastal southeast population’s breeding grounds. Although these two populations look the same, they have key differences in their respective migrations.
The first difference lies in the direction of their migrations. Members of the south-central population winter throughout southern Mexico and Central America, while the coastal southeast population winters in southern Florida and the Caribbean Islands. However, these are just general migration trends, and individuals can vary in their migration destinations. Some individuals have even been known to winter right here on Bald Head Island.
Population range map of the Painted Bunting
The other key migration difference between the two breeding populations is found in their molting strategies. Molting is the process by which bird species shed their old, worn feathers and replace them with new ones. This is an important pre-migration process, as newer feathers are more aerodynamic and increase flight efficiency. The coastal southeast population of Painted Buntings follows the typical pattern of molting before migrating. On the other hand, the south-central population begins their fall migration before molting. They stop in staging areas in northern Mexico to molt before continuing their migration, which is fairly unusual for songbirds.
The reason for this later-molting strategy is that the south-central population begins their migration a few months earlier than their eastern counterparts, allowing them to reach more productive habitats in Mexico fueled by monsoons. Waiting until they reach these more productive staging grounds to feed and molt allows the Painted Buntings to grow stronger and more effective feathers than if they molted in their breeding grounds before migrating. Our coastal southeast breeding population does not need to wait to molt because their breeding grounds are productive enough in the fall to support the efficient growth of new feathers before they migrate.
Bird migrations consist of two alternating phases: passage (time spent flying) and stopover (time spent resting and refueling). To have a successful migration, birds need to have multiple stopover sites along their migration routes. As human development has increased, the amount of suitable stopover habitats has decreased over time. Bald Head Island plays an important role in the migrations of many bird species by providing and protecting key stopover sites, including our maritime forest and salt marshes. Due to the biological value of these habitats towards migratory and threatened bird species, Bald Head Island has been designated as a Global Important Bird Area by the National Audubon Society, 1 of only 720 worldwide.
Sources:
https://ebird.org/news/painted-bunting
https://abcbirds.org/bird/painted-bunting/
https://www.allaboutbirds.org/guide/Painted_Bunting/overview
