Science Center Objects

Patuxent science expands our understanding of the ecological relationships between breeding bird communities and their habitats. For example, Patuxent scientists follow structured decision-making principles to optimize the management of fresh-water and salt-marsh habitats to benefit wetland bird communities. Following pioneering studies documenting the effects of forest fragmentation on woodland birds, studies are now examining forestry silvicultural practices to produce favorable habitats for nesting birds. The benefits of restored islands in Chesapeake Bay demonstrates the importance of properly managing dredge-spoil areas for birds.

Operational programs provide a rich source of data on breeding bird populations. The North American Breeding Bird Survey provides continental trend estimates for more than 400 species, essential information on the status and trends of North American bird populations to support the conservation and management activities of Partners in Flight and the North American Bird Conservation Initiative. The Bird Banding Laboratory hosts a sizable dataset collected during the breeding season across the US and Canada including constant-effort mist netting data from the Monitoring Avian Productivity and Survivorship program coordinated by the Institute for Bird Populations. Patuxent scientists also compiled important breeding bird atlas datasets conducted in a number of states and provinces during the past fifty years.


Southwestern Willow Flycatcher with Nestlings (Credit: Scarlett Howell, USGS, WERC. Public domain.)



North American Breeding Bird Survey

The North American Breeding Bird Survey (BBS) is a long-term, large-scale, international avian monitoring program initiated in 1966 to track the status and trends of North American bird populations. The USGS Patuxent Wildlife Research Center and the Canadian Wildlife Service, National Wildlife Research Center jointly coordinate the BBS program. Following a rigorous protocol, BBS data are collected by thousands of dedicated participants along thousands of randomly established roadside routes throughout the continent. Professional BBS coordinators and data managers work closely with researchers and statisticians to compile and deliver these population data and population trend analyses on more than 400 bird species, for use by conservation managers, scientists, and the general public.








Banding a Least Common Tern Chick

A member of the field crew holds a recently banded least tern chick, displaying both its metal permanent band and its plastic field readable band. (Public domain.)




Productivity of Species of Concern – Least Tern and Common Tern on Poplar Island Restoration Site

Concern has been raised over productivity of two important tern species that have colonized Poplar Island Environmental Restoration Project (PIERP): the Maryland state-listed Least Tern (Sternula antillarum) and Common Tern (Sterna hirundo). Over the 14 year monitoring period at PIERP (beginning 2002), hatching and fledging success of these species has been variable, believed to be linked with natural stressors including avian and mammalian predators and severe weather events.




Citizen Scientists monitoring Avian populations in the Gulf Coast National Parks

Bird Counts: Birds are monitored annually to provide long-term assessment of bird populations. (Public domain.)



Monitoring Birds in National Parks of the Gulf Coast Network

Avian monitoring within the Gulf Coast Network of the National Park Service is challenged to provide valid quantitative data on bird populations within park boundaries with limited financial input. Thus, citizen science (volunteer) bird monitoring has been proposed to achieve reliable estimates of bird populations and to assess the effects of habitat change and temporal dynamics of bird populations.






Black Duck, Anas rubripes, Breeding Range Map

Black Duck, Anas rubripes, Breeding Range Map (Public domain.)

Population Change and Abundance of Black Ducks and Mallards in Eastern North America

Over the last half of the 20th century, the breeding range of American black duck (Anas rubripes) has contracted from central Canada and the Northeastern United States toward eastern Canada. This reduction in size of the breeding range has been reflected in a steady decline of black ducks counted during winter surveys, both the midwinter Waterfowl Survey conducted by the U. S. Fish and Wildlife Service and the Christmas Bird Count. The causes of the declines are unclear. Hunting regulations have been restricted to decrease the harvest. To improve our understanding of black duck population dynamics and of the role of harvest in population change, a variety of surveys, banding studies, and research activities have been conducted for this economically important species. Patuxent staff have been active participants in these activities, and have served on the Technical Committee and Management Board of the Black Duck Joint Venture of the North American Waterfowl Management Plan. Here, we describe Patuxent’s role in assisting with development and analysis of surveys for black ducks in eastern Canada.


Breeding Bird Atlas Explorer Map

Breeding Bird Atlas Explorer Map (Public domain.)


Breeding Bird Atlas Explorer

A Breeding Bird Atlas (BBA) is a widespread survey method that provides distribution maps for all bird species that nest in a specific state or province. Hundreds of participants fan out over several seasons to their assigned blocks on a systematic survey grid; they search for breeding evidence such as a male/female pair of a species on a branch (“possibly breeding”), or an adult feeding its young (“confirmed breeding”). Results are analyzed and mapped to provide a snapshot of the breeding distribution of each species. These largely volunteer projects rarely have the resources to produce data products or collaborate beyond their borders; a paper publication has been the traditional end product.



American Woodcock, Scolopax minor

American Woodcock, Scolopax minor (Public domain.)


Analyses of Woodcock Singing Ground Surveys in the Northeast

Research goals of this project seek to determine if survey routes for American woodcock are sampling represenative habitats and whether routes are distributed proportionally to early successional habitats and biophysical regions across Maine, Vermont, and New Hampshire. If routes are not representatively distributed (i.e., biased), we will evaluate the effects of this bias on estimates of breeding woodcock population trends in the region; document long-term spatial and temporal changes in the breeding populations of woodcock across the northeastern United States; and determine if changes in breeding population distributions are related to historic and current distributions of early successional habitats in Maine, Vermont, and New Hampshire.