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Atlas FAQ

1) Question: If MOS did the Atlas from 1983 to 1987 why do it all over again?

Answer: Bird ranges will change over time even without obvious or extensive habitat or climate change. It is clear that habitat and climate change has taken place over the last twenty years so the birds will have changed as well. To be able to use Atlas results for bird conservation we must repeat the project to see the direction and extent of change in bird populations over the last two decades.

2) Question: I have lots of PA/VA/WV/DE in my block. Do I cover the territory in my block that's in the neighboring state?

Answer: When blocks cross state lines Atlas workers should cover the entire block including all parts of neighboring states in their block.

3) Question: What are the safe dates, and why do I need to pay attention to them?

Answer: Safe dates are intended to forestall counting migrants or transient birds (such as dispersing post nesters) as possible or probable breeders in a block. If you see strong breeding evidence outside of safe dates (for example nest building or a bird with a fecal sac) such behavior is countable for the Atlas.

4) Question: Are there "better" or "higher" codes to aim for within the probable and confirmed categories? e.g. Is a nest code "better" than a code where I don't see a nest?

Answer: There are no probable or confirmed codes that are considered better (or higher). This policy is intended to discourage overly zealous nest searching or other harassment in the name of "upgrading" an already confirmed breeder.

5) Question: Does everyone who works in a block have to report their results separately, or does one person report the pooled results?

Answer: All records from a block should funnel through the person to whom the block is assigned, or the county or state coordinator.

6) Question: When a block crosses a county line does each county report its results separately?

Answer: County coordinators will decide which county will be responsible for coverage of any overlapping block and the coordinator in charge will assign a single block captain to be responsible for each block.

7) Question: How, and where do I report my results?

Answer: An observer may enter her/his results at the Atlas Website in an interactive data form provided to the Atlas Project by the USGS, Patuxent WRC, Biological Resources Division (see below for anticipated posting time). If you do not have web access or are a little technophobic ask your coordinator for help, they should be able to connect you with someone with internet access or be able to enter the data themselves.

8) Question: When will the computer interface for reporting results be up and where will I find it?

Answer: We expect the data entry page will be available by July. It will be posted here at the Atlas Website.

9) Question: When should I report my findings?

Answer: It is generally easiest to enter all of your results at once after the breeding season in late August or September.

10) Question: What do I do if I find a rarity such as one of the birds listed at the end of my Atlas Field Card?

Answer: If you find a rare bird requiring verification you should make an effort to have others document the rarity to support and corroborate your find. In any case you should produce a written report documenting the rare bird on the form provided in your Atlas Packet.

11) Question: I have a block that is divided into quarterblocks. Could you explain quarterblock coverage for me?

Answer: Quarterblocks are intended to reveal breeding distribution on a much finer scale than the standard block (5 km X 5 km). Counties that are experiencing rapid population growth and development and counties with many unique breeding bird species (i.e. Garrett and Somerset) are entirely covered by quarterblocks to show detailed breeding ranges in order to detect subtle changes in bird ranges. The northwestern block in all quadrangles will also receive quarterblock coverage. When an observer covers a quarterblock they need only confirm a bird once in any one of the quarters, but they must strive to see or hear the bird in the remaining three quarters to establish its presence in them.

12) Question: The topographic map of my block is out of date. What can I do to find out about current road, development and habitat conditions in my block in the 21st Century?

Answer: There is a useful compendium of mapping sources and information on land ownership on the Atlas Resources page at this site. The ADC (Alexandria Drafting Company) county map books sold in many outlets around the state (e.g. most grocery stores) are available for all but three of Maryland's counties (Allegany, Garrett, and Somerset). The maps in these handy references are updated biennially and are at the same map scale as the USGS quadrangle maps used to produce the block maps. Mapquest ( provides access to reasonably up-to-date aerial photos, another source of good maps is the DeLorme Company (, and Merlin ( offers satellite images (see the Atlas Resources page for more detail and other sources).

13) Question: What happens to my reports if the habitat changes in my block during the Atlas and some birds are gone from my block?

Answer: All records for the five years from 2002 to 2006 will be recorded in the results of the Atlas Project. The loss of birds due to ongoing change during the years 2002 to 2006 will be reflected in the next atlas.

14) Question: When should I plan to visit my block?

Answer: You will need to visit your block several times, mostly in spring and summer. Productive times to work in a block include mid to late May, all of June, and early to mid-July. Particular species will require special visits at "off" times, for example nesting by goldfinches is best confirmed from late July to early September, and Great Horned and Barred owls are most vocal at night in mid to late winter.

15) Question: When should I consider my block "done" and how long will it take me to do it?

Answer: Most blocks likely host over 90 bird species, but the majority of observers will plateau at 70 to 75 species in a block. As a rule of thumb a block is virtually "complete" at 75 species with half of the species probable or confirmed. Completing a block takes from 20 to 40 hours depending upon the habitat and the knowledge and experience of the observer. Many observers will require around 35 hours or a little less to reach 75 species with half probable and confirmed.

16) Question: Will I be figuring out how common each bird is in my block?

Answer: Block work only requires that you determine the presence of a bird species and try to figure out its nesting status. Other observers will run special surveys in each block called miniroutes to estimate the abundance of the more common and widespread bird species.

17) Question: I don't know a lot about bird breeding behavior and nests, how can I improve my knowledge before I have to learn from the birds in my block?

Answer: There is a list of useful references on bird biology in your blue Atlas Handbook (p. 13). Many of the "life histories" from the old Arthur Cleveland Bent Smithsonian series are available online at: The Maryland Atlas book that covers the 1983-1987 Atlas is also a goldmine of information on the biology and behavior of Maryland birds written from an instate perspective. This book is available from a number of sources, it can often be found at low remaindered pricing (in March 2002 it was offered for $12.95 at Edward R. Hamilton Bookseller on the internet).