boreal blocking effect

[Brian A]

The other day I was out walking the dog/birding some "boreal" habitat (white-cedar, tamarack, balsam fir, white pine) forest near my house and as usual noticing the paucity of any boreal birds.

I had the idea that possibly Lake Michigan and Lake Huron block the normal distribution of boreal birds (at least to some extent) from northern lower Michigan from what would be expected at this latitude.

In comparing maps of several species (red crossbill, evening grosbeak, pine grosbeak) It looks like the species do extend down to about latitude 45 in Wisconsin and Ontario but not (with a bit of exception in Pine Grosbeak) in Michigan.  see http://audubon2.org/birds/cbc/hr/map.html


>From my travels I do not think the habitat is any worse in Michigan in this area for boreal species than either Ontario or Wisconsin.

Anyway, just trying to justify my lack of birding success I guess.

Brian
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.envirolink.org/pipermail/mich-chat/attachments/20060310/16697deb/attachment.html