[order] PODICIPEDIFORMES | [family] Podicipedidae | [latin] aechmophorus clarkii | [UK] Clarks Grebe | [FR] Grebe a face blanche | [DE] Clarktaucher | [ES] Achichilique de Clark | [NL] Clarks Fuut
Subspecies
| Genus | Species | subspecies | Breeding Range | Breeding Range 2 | Non Breeding Range |
| Phoenicopterus | clarkii | ||||
| Aechmophorus | clarkii | ||||
| Aechmophorus | clarkii | ||||
| Aechmophorus | clarkii | NA, MA | w | ||
| Aechmophorus | clarkii | clarkii | n and c Mexico | ||
| Aechmophorus | clarkii | transitionalis | w Canada and w USA | Pacific coast of USA and Mexico |
Physical charateristics
Formerly regarded as a pale morph of the Western Grebe. Intermediates are known. White around eye; bill is orange-yellow. Downy young are white, not gray. Voices differ: Clark’s a one-note creet or criik;
Western, two-noted crik-crick.
Western, two-noted crik-crick.
Listen to the sound of Clarks Grebe
[audio:http://www.aviflevoland.nl/sounddb/C/Clarks Grebe.mp3]
Copyright remark: Most sounds derived from xeno-canto
| wingspan min.: | 80 | cm | wingspan max.: | 85 | cm |
| size min.: | 55 | cm | size max.: | 70 | cm |
| incubation min.: | 23 | days | incubation max.: | 24 | days |
| fledging min.: | 63 | days | fledging max.: | 75 | days |
| broods: | 1 | eggs min.: | 2 | ||
| eggs max.: | 5 |
Range
North America, Middle America : West
Habitat
Lakes, sloughs; in winter, bays, ocean. Breeds mainly on freshwater lakes with large areas of both open water and marsh vegetation. Winters
mainly on sheltered bays or estuaries on coast, also on large freshwater lakes. Great overlap in habitat with Western Grebe, but may feed in deeper water.
mainly on sheltered bays or estuaries on coast, also on large freshwater lakes. Great overlap in habitat with Western Grebe, but may feed in deeper water.
Reproduction
Breeds in colonies. Courtship displays include 2 (or more) birds rushing across surface of water in upright posture with loud pattering of feet, diving underwater at end of rush; “dancing” on water with bits of weed held in bill; also bill-dipping and rit
ualized preening.
Nest: Site is in shallow marsh. Nest (built by both sexes) a floating heap of plant material, anchored to standing vegetation.
Eggs: Usually 2-4. Pale bluish white, becoming nest-stained brown. Incubation by both sexes, about 24 days.
Young:
Climb onto back of parent within minutes after hatching, soon leave nest; are fed by both parents, spend much time riding on parents’ backs. Patch of bare yellow skin on head of young turns scarlet when young beg for food or are separated from parents. A
ge at first flight about 10 weeks. 1 brood per year.
ualized preening.
Nest: Site is in shallow marsh. Nest (built by both sexes) a floating heap of plant material, anchored to standing vegetation.
Eggs: Usually 2-4. Pale bluish white, becoming nest-stained brown. Incubation by both sexes, about 24 days.
Young:
Climb onto back of parent within minutes after hatching, soon leave nest; are fed by both parents, spend much time riding on parents’ backs. Patch of bare yellow skin on head of young turns scarlet when young beg for food or are separated from parents. A
ge at first flight about 10 weeks. 1 brood per year.
Feeding habits
Mostly fish. Apparently feeds mainly on fish at all seasons. Also known to eat crustaceans, insects, polychaete worms, salamanders. Like other grebes, also eats feathers.
Behavior: Forages by diving from surface and swimming underwater, propelled mainly by feet. In one study, tended to feed farther from shore and in deeper water than Weste
rn Grebe. Clark’s and Western are only grebes having structure in neck allowing rapid spearlike thrusting of bill; may be useful in spearing fish.
Behavior: Forages by diving from surface and swimming underwater, propelled mainly by feet. In one study, tended to feed farther from shore and in deeper water than Weste
rn Grebe. Clark’s and Western are only grebes having structure in neck allowing rapid spearlike thrusting of bill; may be useful in spearing fish.
Conservation
This species has an extremely large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence <20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). Despite the fact that the population trend appears to be decreasing, the decline is not believed to be sufficiently rapid to approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size may be moderately small to large, but it is not believed to approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern.
Northern breeders apparently migrate west to Pacific Coast.
Northern breeders apparently migrate west to Pacific Coast.
Migration
Range imperfectly known; overlaps much of that of Western Grebe, becoming more common to the south and west.
Distribution map
