Michael Conner wrote:

>Please excuse the ignorance of a novice, but learning birder. What does
>"intergrades" mean? I have looked through several books and been unable
>to find it.

Usually the word "intergrade" is restricted to individuals intermediate
between two subspecies (races) of a species, presumably sharing genetic
material and presumably having been born (or at least conceived) in the
geographic area where the two subspecies come together. They are not the
same as "hybrids," a term that should be restricted to individuals sharing
genetic material of two different species. The situation is really
confusing in Northern Flickers, in which intermediate individuals (called
both hybrids and intergrades in the literature) are very widespread,
indicating long-term gene flow between previously distinct "yellow-shafted"
and "red-shafted" populations. In most species, intergrades occur in a
very narrow zone.

> Is morph the same as race?

No, "race" is the same as subspecies, a morphologically and geographically
distinct population of a species. Good examples in this area are Downy and
Hairy woodpeckers. Both species have well-defined dingy-looking subspecies
in western WA, and both have two additional subspecies in eastern WA, a
very white-bellied one in the Far East and a slightly dirtier white-bellied
one on the east side of the Cascades (which some might argue was merely an
intermediate population).

Morph is as the hawk book defined it, a color (or shape or size) variant
*within* a population. Reddish Egret, Snow Goose, buteo hawks, Gyrfalcon,
and Eastern Screech-Owl are good examples of polymorphism (more than one
morph in a population or species). It *has* to be independent of sex and
age to be a "morph."

> Do different morphs within the same species interbreed?

Yes, that's how we know they are morphs within a species, rather than
different species--no matter how different they look from one another. The
dark and white morphs of Snow Goose were considered different species
("Blue Goose" and Snow Goose) until we realized they interbred freely.

> If so, is there a tendency for a particular morph to be dominant
> in the offspring? Are dark morphs more dominant as I might
> expect from observing other species?

Yes, morph ratios are controlled genetically. But I wouldn't say dark
morphs were dominant, because they are usually less common than light
morphs in buteo hawks, for example. It depends on the species.

> If two members of the same morph breed, will all the offspring
> be of the same morph as the parents?

No, they are sorted genetically, just like blue-eyed vs. brown-eyed in
people, and you can find both morphs in the same nest or litter.

> Is albinism a type of morph?

No, it's a genetic condition that causes a suppression of pigment production.

> Anything else you might tell me including references that might
>help me.

The most interesting case of polymorphism is that of male Ruffs, and the
reference is _The Ruff_, by Johan van Rhijn. You can find some info about
polymorphism in birds in ornithology texts, and info about polymorphism in
general in evolution texts.

> Finally, there seems to be a distinct absence of a book that
>defines the words that birders on and off the list throw around. Does
>anyone know of such a book, preferably one still in print? An online
>resource would be even better.

Too bad Chris Leahy's _The Birdwatcher's Companion_ is now out of print.
It's the best bird encyclopedia, although some might argue for the larger,
better illustrated _Audubon Society Encyclopedia of North American Birds_,
by John Terres. Snap up either of them if you find it in a used book
store.

Dennis Paulson, Director phone: (206) 756-3798
Slater Museum of Natural History fax: (206) 756-3352
University of Puget Sound e-mail: dpaulson at ups.edu
Tacoma, WA 98416