It was with great anticipation that I received the rather expensive (~280$)two volume "Ducks, Geese, and Swans" published by Oxford Univ Press as part of their Bird Families of the World series.
Seeing the Canada and Cackling Goose standing next to each other on the cover of vol. 1 only heightened my glee.
The first couple hundred pages offer a nice overview of waterfowl biology. I have yet to read this section in its entirety, but I could not find a reference to a potentially interesting topic in waterfowl biology: that is, the default plumage is male. So, a bird lacking sex hormones (estrogen, testosterone) will look more like a male than a female. Females low on estrogen will look like odd males, perhaps prompting the report of hybrids, and have been loosely termed "intersex ducks" in birding circles. Anyway, this point, perhaps somewhat
trivial but of some potential importance to field ID, seems to have been omitted.
Much more important to most everyone reading this are the species accounts and how well they cover ID, distribution, and subspecies.
The short answer is horrid, okay, and highly variable.
Looking at wigeon, the discussion of ID of adults is extremely basic (not better than the old Golden Guide) and for immatures, states that "both sexes [of American] appear much like immature Eurasian Wigeon." Lots of help there. They do manage to spend almost as much time telling you how to separate American
Wigeon from Chiloe Wigeon, however, as "escaped birds often occur." Though no mention of Eurasian x American Wigeon is made, we are warned about hybrids with Chiloes. Indeed, a great fault re: ID is that mention of hybrids is rarely made, and for some ID quandaries, such as wigeon, awareness of these and their
appearance is critical.
Another example: Under scaup, head color and wing stripe are emphasized. A brief and misleading reference to head and bill shape differences is made. And so on. The illustrations are pretty, but not terribly useful re: ID. Some chicks are shown, but only for a few species.
The maps are often incorrect. A quick thumbing through the book revealed that Barrow's Goldeneye is shown as wintering in the lower Great Lakes, where they are vagrants, whereas Lesser Scaup are not shown wintering in the interior anywhere (and they are not rare on the Great Lakes, except when frozen). Barrow's Goldeneye are shown as being resident in the High Cascades, where they breed but would freeze to death during winter but are not shown as wintering on Washington's n. Olympic Coast, where common. Long-tailed Ducks, apparently, don't winter s. of central Vancouver Island, but Black Scoters winter all the way into Mexico. For some species, such as RB Merg, a "Polar View" is used for the map, making the bird's precise range difficult to interpret; in any case, it certainly is shown in broad strokes when compared with species limited to one continent, where an attempt is made to show the range in great detail.
Then there is the peculiar selection of terms for these maps: "Migrant breeding" and "Migrant non-breeding." The use of "migrant" is baffling for these labels mean "breeding" and "wintering" respectively. I realize that ducks do move about during the "winter" or "resting" season depending on open water
and other factors, and there's the issue of whose winter (n. hemisphere vs s. hemisphere) one's talking about. However, the use of "migrant" is extremely misleading because the ranges NEVER display migration range, which is left undepicted in all maps.
The text offers a better description of ranges, sometimes not
containing the same errors shown in the maps. And the text gives valuable info on population levels, sometimes in great detail (though to some extent this can be obtained from Wetlands International's "Waterfowl Population Estimates" -- an excellent tome recommended to all). So, for population issues, these books are quite useful. However, range errors exist here, too. The wintering of Black Scoter to Mexico is repeated. And, they mention the regular occurrence of Eur Wigeon in North America, but state that it is particularly numerous in the Aleutians and Mexico. Yes, Mexico. I guess we've been missing the large flocks in Baja.
In the Brant account, subspecific range and numbers is extremely well covered, including "Gray-bellied Brant." Also, the author notes that "Lawrence's Brant" may not be GB Brant at all, but a now extirpated darker e. North American population of Brant. However, the account gives little help on ID of these races.
The Canada Goose account is a disaster. Canada and Cackling aren't split, though the AOUs decision is alluded to. No where does this account suggest which races will be put with which species. A vague attempt at discussing subspecific ID is made, so much so as to make one wonder why they wasted the space. The maps are a hodgepodge of Fish and Wildlife Service defined "populations" (which contain several races) to specific maps for several (Aleutian, minima, Dusky). A map labelled "Lesser" I suspect contains parvipes and taverneri
ranges, though the text earlier defines these as separate subspecies. In any case, if you are interested in Canada and Cackling Goose racial ID and range, this book is nearly worthless. The BNA account, which is several years old, is far
better. For that matter, so is Bellrose's book and Johnsgard's from the 1970s (or is it early 80s -- too lazy to get up and drag down the volumes).
On the other hand, the discussion of range and subspecific ID on Common Eider is far more detailed and useful, probably exceeding that which can be obtained from most other sources.
As for food, displays, breeding and life cycle, much of this is interesting, but outside of any area of expertise I have. For some species, a detailed account of molt cycle is given, which is quite nice, but for many species this information is not provided.
In reality, for North America, access to the BNA accounts and Sibley (especially if you can access Dave himself :o) will do you far more good than this extremely expensive set. For outside North America, there are many sources which would easily replace this set, depending on where you're going; and in many respects, the much less-expensive Madge and Burn book on Waterfowl is equal or superior.