How to Use the NOVA Bird Checklist
The Checklist of Birds of Northern Virginia was created to assist birders in the area covered by our Audubon chapter. The checklist prints full-size on 11"x17" paper. It can be printed on legal size paper. (You will need to resize it to fit. Different printers work differently, but look for either a "scale to fit" option, or a scaling option using 75%. Also use a two-sided printing option if available.) Printed copies are available from the Audubon office.
The checklist is based on the most readily available information about birds that occur in Northern Virginia, in what numbers and on what dates: eBird. Read further for details on the checklist.
What is eBird? eBird is an online real-time checklist program www.ebird.org supported by the Cornell Laboratory of Ornithology at Cornell University. As a “citizen science” tool, eBird’s data are comprised of reports entered by thousands of individual birders about the birds they have seen or heard, the number of individual birds, and the location, time and date of the observation. For Northern Virginia, we used eBird data for 2005-2015, which included almost 90,000 reports from birders in our region.
This information allowed us to see what species have been found in Northern Virginia, and list them along with annotations about which seasons they are here and how abundant they are – very rare through abundant. Details on how we developed the checklist are available here.
Using eBird. ANSV encourages you to enter your observations in eBird. Your sightings will become part of the eBird database that is used in scientific analysis of trends in bird population levels, distributions and migration patterns, as well as for projects like our checklist. The analysis of bird populations is critical to understanding how birds are being impacted by habitat change, climate change, and other conditions, and in developing conservation practices and habitat protection and restoration efforts. You can set up a free eBird account at www.ebird.org. eBird will also help you track your own bird list.
What area is covered by the checklist? The eBird data covers Arlington, Fairfax, Fauquier, Loudoun, Prince William, Rappahannock, and Stafford counties and the cities of Alexandria, Fairfax, Falls Church, Fredericksburg, Manassas, and Manassas Park.
Seasonal annotations. The seasonal information on the checklist should be regarded as a guide, not as a definitive indication. Thus, birders should not necessarily expect to find the species during every month of the season. Migratory species in particular may be here only part of a season.
Chimney Swifts, for example, are shown on the checklist as present in the Fall (September through November). Chimney Swifts are indeed here in September but are usually gone by mid-October and are not here at all in November.
Similarly, Magnolia Warblers are shown on the checklist as present in Spring (March through May), but appear in our area in mid-April. A birder using the checklist in the spring month of March is not likely to see the Magnolia Warbler.
Abundance annotations. As with seasonal information, the abundance information on the checklist is a guide, not definitive. Also, birders should expect to find the species in appropriate habitats. They are not likely to find ducks in dry grassland habitats, for example, except for birds flying over.
Introduced species. Any species denoted with (I) is a species introduced in Virginia. It is not native to the state and was brought to the area and is sustaining a wild population. This group includes a number of European species introduced to the United States that have become familiar and well established, such as the House Sparrow and European Starling.
Accidental or vagrant species. The main checklist is followed by a shorter list of species that are accidental or vagrants in Northern Virginia. Accidental species are those that have been observed only a very few times – less than 6 times in the last 50 years on the Virginia Society of Ornithology’s official list for the state. A vagrant is a bird that has strayed far out of its expected range, for example, blown in by a storm.
Limitations of eBird data. While eBird data are an invaluable resource, they do have some limitations.
eBird is based on what individual birders have reported. That is, it tells us what birds were observed during the times and at the places where birders go. This is a different type of data than would be found during a survey using a formal protocol where coverage and timing can be planned.
Some locations are heavily birded, others are not. Some locations, such as parks and refuges, may have nocturnal or other species that are not observed because the locations are not open when these birds may be active. The result is that the abundance indicators for such species such as Owls may be lower than what would be found with more formal data sources.
Also, when a rare bird shows up in our area, many birders go to see it and enter reports in eBird. The result is a lot of reports for 1 or 2 individual birds. In preparing our checklist, we looked at the individual reports where we thought this might be the situation, and adjusted the list by moving such species to the short list at the bottom of the checklist.
Who put this checklist together? The checklist was developed by a team led by Dixie Sommers with input from Tom Blackburn, Greg Butcher, Greg Fleming and Laura McDonald.