Annotated checklist and data resource
text © Don Roberson
photos copyrighted by photographer(s) credited
all photos taken in Monterey County, California
Western Grebe Aechmophorus occidentalis
Western Grebe is the common large grebe in Monterey County (MTY). It is found widely on both freshwater lakes inland and on saltwater inshore, especially in sheltered bays and estuaries. In years when water levels are right, hundreds nest at Lake San Antonio. Even more arrive in winter along the coast, starting in October and remaining into March.
Western Grebes are large gray and white grebes with long dagger-like bills. They have bright red eyes. Bill color ranges from very dull gray-green in winter (below left) to a much brighter yellow-green as spring approaches (below right). Note also differences in head pattern between the two grebes; the righthand bird is showing whitish spots in the lores and might be a candidate for Clark's Grebe but in the field was thought to have a greenish-yellow tone to the bill in comparison to adjacent orange-billed Clark's Grebes.
Separating Western and Clark's Grebes is not always easy. They usually occur together in the same flocks, and Clark's is generally identified by its orange-yellow bill, but the fact that the eye is in the white part of the face, by paler flanks, and by a narrower black stripe connecting the crown with the back. But Clark's Grebes in fall and winter (in basic or juvenal plumages) can be problematic since dark often appears around the eye and bill colors less in intensity. There is still much to be worked out between the two sibling species when in that ambiguous plumage. It is possible that the grebe above right, and labeled "Western" here, is actually a Clark's Grebe. For more information see Ratti (1979), Nuechterlein (1981), Storer & Nuechterlein (1992), and Eckert (1995).

All photos © D. Roberson. Top 6 Mar 2004 Elkhorn Slough; above left Mar 1986 Moss Landing; above right 6 Mar 2004 Elkhorn Slough; left (both species) 5 Apr 1991 Moss Landing harbor; below 14 Nov 2004 Monterey Harbor.

One problem in studying Aechmophorus grebes is that they seem to spend an inordinate amount of time asleep (left), making it difficult to study bill color or facial patterns. The red eye is often obvious, however.
Where to find a Western Grebe in MTY: This large grebe is common and widespread in migration and winter, and some will remain through the summer. When nesting, hundreds of pairs can be seen around the north end of Lake San Antonio. Favored winter locales are:
  • Elkhorn Slough and Elkhorn Slough Estuarine Research Reserve, and Moss Landing Harbor
  • Monterey harbor, sometimes in the harbor but more often just offshore the Coast Guard pier or off the tip of the Commercial Wharf (Wharf #2, the one you can drive on and park in the metered slots). 
  • Just offshore the sandy beaches from Ft. Ord south to Del Monte Beach, Seaside; scope from the "Cross" just south of Monterey Beach Hotel or from the roads that dead-end at the ocean north of the hotel
  • Sheltered covers like that between Lovers Pt. and Otter Pt. in Pacific Grove, or Stillwater Cover in Pebble Beach
  • Just off the beach at the Big Sur R. mouth or the Pajaro R. mouth
Large numbers are found on the local Christmas Bird Counts (CBC). The recent average* for the Monterey Peninsula CBC is 700 Western Grebes, and on the Moss Landing CBC it is 973 grebes (but some of those are in adjacent Santa Cruz County). There have been years when runs of small fish concentrate huge numbers just offshore; an astonishing 12,356 were reported on the Moss Landing CBC on 1 Jan 2001.
* = "recent averages" for Christmas Bird Counts are found by compiling the totals reported for last dozen counts, throwing out the high and low counts that may be biased by observer error or bad weather, and averaging the remaining ten counts.
Go back to
Clark's Grebe
Literature cited: Use the following links to other portions of the MTY checklist:
Part 1: Waterfowl through Grebes
Part 2: Albatrosses through Frigatebirds
Part 3: Herons through Cranes
Part 4: Plovers through Sandpipers
Part 5: Jaegers through Alcids
Part 6: Doves through Woodpeckers
Part 7: Flycatchers through Larks
Part 8: Swallows through Pipits
Part 9: Waxwings through Warblers
Part 10: Tanagers through Sparrows
Part 11: Grosbeaks through Finches
or just the plain Checklist (no annotations)
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Page created 23 Nov 2004