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What the sources say

Western GrebeAechmophorus occidentalis

Every figure, record and mechanism on the Western Grebe profile was written from a source, and this is the working table behind it: 44 claims checked word for word against these sources. The left column is what the page says. The right column is the source's own words, copied, not paraphrased; a ... marks a cut and[brackets] an insertion. Open any source and check it yourself.

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Source
01

Animal Diversity Web, University of Michigan

Aechmophorus occidentalis (western grebe). Animal Diversity Web, University of Michigan.

The page saysFreshwater lakes and marshes with rushes and tules across western North America in summer
The source saysIt lives on freshwater lakes that have rushes and tules during the breeding season.
The page saysA western grebe's red eye is surrounded by dark coloring and its bill is dull yellow or olive, while a Clark's grebe has white around the eye, a bright yellow to orange-yellow bill, whiter flanks, and a paler gray back.
The source saysThe Western Grebe has a dull yellow or olive-colored bill and red eyes surrounded by dark coloration... Clark's grebes have white surrounding the eye and a bill that is bright yellow to orange-yellow. Their flanks have more white areas and the back is a lighter gray.
The page saysbreeding on freshwater lakes with rushes and tules
The source saysIt lives on freshwater lakes that have rushes and tules during the breeding season.

Source
02

Audubon Field Guide to North American Birds

Western Grebe. Audubon Field Guide to North American Birds.

The page saysA neck structure, found among grebes only in it and Clark's grebe, for rapid spear-like thrusting of the bill
The source saysWestern Grebe and Clark's Grebe are the only grebes having structure in neck allowing the rapid spear-like thrusting of bill
The page saysmostly sheltered coastal bays and estuaries on the Pacific coast in winter
The source saysWinters mainly on sheltered bays or estuaries on coast
The page saysMostly fish, plus crustaceans, insects, worms, salamanders, and feathers
The source saysThe Western Grebe apparently feeds mainly on fish at all seasons and in all habitats. Also known to eat crustaceans, insects, polychaete worms, salamanders. Like other grebes, also eats feathers.
The page saysDuring a courtship display called rushing, two or more birds rear upright and sprint side by side across the surface, feet pattering loudly, then dive underwater at the end of the run.
The source saysMost conspicuous is a display in which two (or more) birds rear up to upright posture and rush across surface of water side by side, with loud pattering of feet, diving underwater at end of rushNote: 'rear up to upright posture' is the source's own wording; the 'up to' there is idiomatic, not a quantity hedge
The page saysAn adult measures 53 to 74 centimeters (21 to 29 inches) long and weighs 0.8 to 1.6 kilograms (1 pound 12 ounces to 3 pounds 7 ounces), with males slightly larger.
The source saysSexes similar; male slightly larger — Length: 21 in-2 ft 5 in (53-74 cm); wingspan: 2 ft 7 in-2 ft 11 in (79-90 cm); weight: 1 lb 12 oz-3 lb 7 oz (800-1.6 kg).Note: 21 to 29 inches restates the source's own '21 in-2 ft 5 in' (2 ft 5 in = 29 in); 0.8 to 1.6 kilograms restates its own '(800-1.6 kg)' (800 g = 0.8 kg)
The page saysWestern and Clark's grebes are the only grebes with a structure in the neck that thrusts the bill forward like a spear, which may help them spear fish, though how they use it isn't well known.
The source saysWestern Grebe and Clark's Grebe are the only grebes having structure in neck allowing the rapid spear-like thrusting of bill; may be useful in spearing fish, but use of this behavior is not well known.
The page saysThe species appears to feed mainly on fish, and is also known to eat crustaceans, insects, worms, salamanders and, like other grebes, feathers.
The source saysThe Western Grebe apparently feeds mainly on fish at all seasons and in all habitats. Also known to eat crustaceans, insects, polychaete worms, salamanders. Like other grebes, also eats feathers.
The page saysA pair builds its nest as a floating heap of plant material anchored to standing marsh vegetation, in a colony.
The source saysNest: Site is in shallow water marsh. Nest (built by both sexes) a floating heap of plant material, anchored to standing vegetation.Note: 'in a colony alongside other pairs' from the same page's Nesting line: 'Breeds in colonies.'
The page saysThe female lays two to four pale bluish-white eggs, rarely as few as one or as many as six, and both parents incubate them for about 24 days.
The source saysA Western Grebe generally lays 2-4 eggs, rarely 1-6. The eggs are pale bluish white, becoming nest-stained brown. Incubation by both sexes, about 24 days.
The page saysChicks climb onto a parent's back within minutes of hatching and soon leave the nest, and both parents feed them.
The source saysClimb onto back of parent within minutes after hatching, soon leave nest; are fed by both parents.
The page saysA bare patch of yellow skin on a chick's head flushes scarlet when it begs for food or gets separated
The source saysPatch of bare yellow skin on head of young turns scarlet when young beg for food or are separated from parents.
The page saysa young grebe takes its first flight at about 10 weeks old
The source saysAge at first flight about 10 weeks.
The page saysAround the start of the 20th century, tens of thousands of these grebes were killed for their feathers, and numbers appear to have recovered after that
The source saysAround beginning of 20th century, tens of thousands were killed for their feathers. Apparent recovery since, and has begun breeding in new areas not occupied historically.Note: 'after that' places Audubon's 'Apparent recovery since' after the plume trade, not after the 1975-2010 decline
The page sayswintering mainly on sheltered coastal bays and estuaries
The source saysWinters mainly on sheltered bays or estuaries on coast
The page saysIt hunts by diving and swimming underwater, driven mainly by its feet.
The source saysForages by diving from surface and swimming underwater, propelled mainly by feet.
The page saysTwo or more birds rear up side by side and run across the surface with a loud pattering of feet
The source saystwo (or more) birds rear up to upright posture and rush across surface of water side by side, with loud pattering of feetNote: settle #889 (vibe.reason)

Source
03

AnAge: The Animal Ageing and Longevity Database

Aechmophorus occidentalis. AnAge: The Animal Ageing and Longevity Database.

The page saysA wild western grebe has been recorded living to 14 years old.
The source saysMaximum longevity 14 years (wild)
The page saysweightKg: 1.48
The source saysAdult weight 1476 gNote: settle #889; Audubon 800 g to 1.6 kg, all Light class

Source
04

Birds of the World, Cornell Lab of Ornithology

Western Grebe (Aechmophorus occidentalis), version 1.0. Birds of the World, Cornell Lab of Ornithology.

The page saysWestern grebes range from southern Canada to the Mexican Plateau
The source saysThe Western Grebe is a conspicuous waterbird of western North America that ranges from southern Canada to the Mexican Plateau.
The page saysWestern and Clark's grebes were treated as color phases of one species, the western grebe, from 1886 until 1985.
The source saysBecause Western Grebe and Clark's Grebe were from 1886 until 1985 considered color phases of the Western Grebe
The page saysThe case for splitting them began with the finding that each mates mostly with its own kind, and a DNA study found them about as distinct as other species in the same genus.
The source saysEvidence for the renewed specific status of Western Grebe began with finding that Western and Clark's grebes mated assortatively
The page saysa DNA study found them about as distinct as other species in the same genus
The source saysindicated that the median DNA sequence distance between the species was comparable to such distances between other congeners

Source
05

Clifton, Hedrick & Biewener 2015

Clifton, Hedrick & Biewener (2015). Western and Clark's grebes use novel strategies for running on water. Journal of Experimental Biology.

The page saysWestern grebes do something few vertebrates can: they run upright across open water.
The source saysFew vertebrates run on water. The largest animals to accomplish this feat are western and Clark's grebes (Aechmophorus occidentalis and Aechmophorus clarkii).
The page saysTied with Clark's grebe as the largest animal known to run on water, sprinting across a lake in a courtship display called rushing.
The source saysThe largest animals to accomplish this feat are western and Clark's grebes (Aechmophorus occidentalis and Aechmophorus clarkii). These birds use water running to secure a mate during a display called rushing.
The page saysA 2015 study filmed them with high-speed video
The source saysHigh-speed video recordings elucidate the hindlimb movements of grebes rushing in the wild.Note: 2015 is the paper's publication year (Journal of Experimental Biology 218, 2015)
The page saysWestern grebes and their close relative, Clark's grebe, are the largest animals known to run on water.
The source saysThe largest animals to accomplish this feat are western and Clark's grebes (Aechmophorus occidentalis and Aechmophorus clarkii).
The page saysa rushing grebe's feet hit the surface at stride rates reaching 10 Hz
The source saysrushing grebes use exceptionally high stride rates, reaching 10 Hz
The page saysthat slapping alone supplies up to 30 to 55 percent of the lift the bird needs to keep from sinking
The source saysgrebe foot size and high water impact speed allow grebes to generate up to 30-55% of the required weight support through water slap alone
The page saysFlattened bones in its foot cut drag, letting it pull each foot sideways out of the water.
The source saysflattened foot bones reduce downward drag, permitting grebes to retract each foot from the water laterally
The page saysRoughly Ten Times Heavier Than a Basilisk
The source saysGrebes weigh an order of magnitude more than the next largest water runners, basilisk lizards (Basilicus basiliscus)Note: 'roughly ten times' is a plain-language rendering of 'an order of magnitude'; 'heavier' restates 'weigh ... more'
The page saysA grebe outweighs it by about an order of magnitude, so it faces a greater challenge holding up its own weight.
The source saysGrebes weigh an order of magnitude more than the next largest water runners, basilisk lizards (Basilicus basiliscus), and therefore face a greater challenge to support their body weight.Note: 'so' restates the source's own 'and therefore'
The page saysIn a 2015 study, researchers filmed rushing grebes in the wild with high-speed cameras and ran lab experiments with physical models and a preserved grebe foot, to estimate how much of the bird's weight slapping the water holds up.
The source saysHigh-speed video recordings elucidate the hindlimb movements of grebes rushing in the wild. We complement these findings with laboratory experiments using physical models and a preserved grebe foot to estimate how slapping the water surface contributes to weight support.Note: the year 2015 is the paper's own publication year, quoted separately in the 'A 2015 study' claim above
The page saysThe basilisk lizard is the next-largest animal known to run on water.
The source saysGrebes weigh an order of magnitude more than the next largest water runners, basilisk lizards (Basilicus basiliscus)
The page saysat stride rates reaching 10 strides a second
The source saysrushing grebes use exceptionally high stride rates, reaching 10 HzNote: settle #889 (vibe.reason)

Source
06

Wilson et al. 2013

Wilson et al. (2013). Citizen Science Reveals an Extensive Shift in the Winter Distribution of Migratory Western Grebes. PLoS ONE.

The page saysA study of 36 years of Christmas Bird Count data
The source saysWe used hierarchical modeling with a Bayesian framework applied to 36 years of Audubon Christmas Bird Count data to assess continent-wide and regional population trends in western and Clark’s grebes ( A. clarkii ) from 1975 to 2010.
The page saysthe wintering population of the two species fell by roughly 52 percent after 1975
The source saysthe North American wintering population of Aechmophorus grebes decreased by ∼52% after 1975
The page sayscrashing by about 95 percent in the Salish Sea while growing by more than 300 percent along the California coast
The source saysAbundance decreased by about 95% over 36 years in the Salish Sea but increased by over 300% along coastal California.Note: the study's main analysis estimated trends for Aechmophorus spp. (both species), which the sentence's subject 'the wintering population of the two species' keeps
The page saysmoving the wintering range's center about 895 kilometers south between 1980 and 2010
The source saysthe mean centre of the species distribution shifted south by an estimated 895 km between 1980 and 2010
The page saysSince the mid-1980s, the Pacific sardine stock off California grew from a few thousand metric tons to more than two million, while both the abundance and availability of Pacific herring declined in the Salish Sea.
The source saysSince the mid-1980s, the Pacific sardine stock off the California coast increased from a few thousand metric tonnes to over two million. At the same time both the abundance and availability of Pacific herring declined in the Salish Sea.
The page saysThe 2013 study that measured the shift suspects a change in the forage fish they eat, and says the idea still needs testing.
The source saysMechanisms underlying this shift require further study but we hypothesize that it may be related to a change in the abundance and availability of their forage fish prey base.Note: 2013 is the paper's publication year (PLoS ONE 2013); 'suspects' and 'the idea still needs testing' carry the source's 'hypothesize ... may be related' and 'require further study'

Source
07

The IUCN Red List of Threatened Species 2019

Aechmophorus occidentalis. The IUCN Red List of Threatened Species 2019: e.T22696631A139355294.

The page saysthe IUCN rates the species Least Concern
The source saysIUCN Red List category: Least Concern (LC).

How the table was made: a writer drafted the profile from these sources and logged each claim with its quote, a reviewer with nothing but this table checked every sentence said no more than its quote, and a script confirmed each quote appears word for word in the source. The method is in the site'sAbout page.