Richard Wood wrote:

>What exactly is a "safe date"?
> 
> Richard
> 
>  
>
A safe date is the date in which birds seen in an atlas block my be 
listed as possible breeders due to their migration/winter wondering 
normally being completed and the birds being on nesting territory.

Here is the quote from the website of the breeding bird atlas project 
website:


      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.

If you would like to read more about the project, you can find all the 
information that you would care to know here:

http://www.mdbirds.org/atlas.html

Ed Boyd
Westminster, MD