northern vs southern bald eagles

[Jeff Nadler]

Once separate sub-species, I believe, there is a notable size difference in eagles geographically. The southern breeders are noted as 15-20% smaller, thought to be climate influenced.

I was wondering for publication use where region is a facet of the article, the typical editor, publisher, etc. knows the difference and cares? A bald eagle expert and ornithologist may instantly tell, but not sure.

Why do I ask? If a northeastern publication with a bald eagle story is looking for images, is it fair to send them Florida eagle photos (or vice versa)?

 

[Steve Foss]

Jeff, while the weight/body size distinction is true, Sibley also notes that southern breeders on average have tails shorter by 20 percent and wings shorter by 10 percent than northern breeders. Proportionally, which is what a person can most easily recognize in photos, the differences may not be all that obvious unless there's another species of bird or some other element in the frame that allows an easy gauge of size. And these are very general guidelines, with exceptions quite common.

Where's the geographic line? There are two subspecies of bald eagle, according to Peterson's guide to hawks, one in Canada and Alaska and another in the lower 48. Also, northern eagles often move south for part of the winter, paricularly along major waterways, so I have no doubt there's some intermingling.

I doubt the average photo editor of a birding publication can easily tell the difference between southern and northern breeders, and I'm sure many will not care, unless the article accompanying the art in some way deals with the differences between the two and the art is meant to illustrate those differences.

Probably it's best just to submit as per the publication's guidelines and not distinguish between the two. If an editor knows and cares about the difference (and hasn't mentioned it when sending out a "wants" list,) he or she will let you know soon enough. Whether that's "fair" or not I don't know. Just seems to make sense to me.

 

[Mara grose]

Has anyone noticed a difference in the vocals of a northern vs Southern bald eagle?
I ask because I think a young northern female stayed in Florida, she's huge and sounds more like a grunting duck.