Subject: Re: Olympic Gull update
Date: Jan 19 19:41:53 1997
From: Mike Patterson - mpatters at orednet.org




>
>
>This verges on a question that occurred to me as I drove in my car the
>other day: What is the definition of a "superspecies?"
>

Generally speaking, a superspecies consists of two or more sibling species
that are very closely related. The Western Flycatcher is now considered a
superspecies consisting of Pacific-slope and Cordilleran Flycatcher for
example. The siblings within a superspecies may or may not interbreed
(it's not a requirement or anything).

The "Northern Pink-footed Gull" complex as it is generally called includes
all the species that have turned up in this discussion and more there are
regular occurrences of interbreeding at the overlaps between all members.
The most annoying being the Western x GW cross, because it's easiest to detect
and therefore most soundly documented. I suspect that with effort a similar
Herring x GW cline could be documented across Canada, but the differences are
are more subtle and not as easily sorted out in the field.

As long as I'm at it, I'd like to put in my two cents regarding this "Olympic"
Gull thing. It smells of "Northwestern" Crow. It's inexact language which
may be permissible between birding pals (as would terms like "tail", "snog"
and "geebhaw"), but they have no place in the general communication process.
"Olympic" Gull doesn't exist even as a cleanly identifiable hybrid type.
I think we should stick to the terminology "mostly-Western", WestxGW and
"mostly GW" when discribing the mottly assortment of "Northern Pink-footed"
Gulls that grace our Pacific shores and garbage dumps.



--
*********************************** I was of three minds
* Mike Patterson, Astoria, OR * like a tree
* mpatters at orednet.org * in which there are three blackbirds.
*http://www.pacifier.com/~mpatters* -Wallace Stevens