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What the sources say

Blue JayCyanocitta cristata

Every figure, record and mechanism on the Blue Jay profile was written from a source, and this is the working table behind it: 45 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

National Audubon Society, Guide to North American Birds

Blue Jay. National Audubon Society, Guide to North American Birds.

The page sayscan imitate the scream of a Red-shouldered Hawk
The source saysthey can do a remarkable imitation of the scream of a Red-shouldered HawkNote: tagline; stats.superpower
The page saysOak and pine woods, suburban gardens and towns
The source saysOak and pine woods, suburban gardens, groves, towns.Note: stats.habitat
The page saysMostly plant matter such as acorns, nuts and seeds, plus insects and birds' eggs
The source saysMost of diet is vegetable matter (up to 75% of diet for year, higher percentage in winter), including acorns, beechnuts, and other nuts, many kinds of seeds, grain, berries, small fruits, sometimes cultivated fruits. Eats many insects, especially caterpillars, beetles, grasshoppers, and others; also eats spiders, snails, birds' eggsNote: stats.diet
The page saysA blue jay's raucous jay-jay is one of many calls
The source saysA raucous jay-jay, harsh cries, and a rich variety of other calls.
The page saysAudubon lists a rich variety of others, and one is a musical queedle-queedle
The source saysa rich variety of other calls. ... Also a musical queedle-queedle.
The page saysOne call is almost identical to the scream of the Red-shouldered Hawk
The source saysOne is almost identical to the scream of the Red-shouldered Hawk
The page saysthe jay can do a remarkable imitation of it
The source saysthey can do a remarkable imitation of the scream of a Red-shouldered Hawk
The page saysIt has a crest, a black necklace, bright blue wings and tail, and white wing-bars
The source saysdull blue-gray on the back, bright blue on the wings and tail. Note crest, black necklace, white wing-bars, and tail corners.
The page saysBlue jays harvest acorns and store them in holes in the ground
The source saysWill harvest acorns and store them in holes in the ground.
The page saysA blue jay is 25 to 30 cm long, with a wingspan of 34 to 43 cm, and weighs 70 to 100 g
The source saysLength: 9-12 in (25-30 cm); wingspan: 13-17 in (34-43 cm); weight: 2.5-3.5 oz (70-100 g).
The page saysMales are slightly larger than females
The source saysSexes similar; males slightly larger
The page saysBlue jays are present all year in most of their range
The source saysThe Blue Jay is present all year in most of its range
The page saysSome migrate south in fall, but not south of the United States
The source saysvariable numbers migrate south in fall; big southward flights in some years, with thousands on the move, although they do not go south of the United States.
The page saysBlue jays are omnivores that may feed on almost anything
The source saysit may feed on almost anythingNote: 'omnivores' from Audubon's 'Diet Omnivorous.'
The page saysUp to 75% of the diet over a year is vegetable matter, and more of it in winter
The source saysMost of diet is vegetable matter (up to 75% of diet for year, higher percentage in winter)
The page saysJays also eat many insects, especially caterpillars, beetles and grasshoppers
The source saysEats many insects, especially caterpillars, beetles, grasshoppers, and others
The page saysYoung blue jays leave the nest 17 to 21 days after hatching
The source saysYoung leave nest 17-21 days after hatching.
The page saysBoth parents bring them food
The source saysBoth parents bring food for nestlings.
The page saysthe clutch is usually 4 to 5 eggs
The source says4-5, sometimes 3-7.
The page saysAudubon lists birds' eggs, and sometimes baby birds, among the foods a blue jay eats
The source saysalso eats spiders, snails, birds' eggs, sometimes small rodents, frogs, baby birds, carrion
The page saysjays slip furtively through the trees when going to rob the nest of another bird
The source saysthey slip furtively through the trees when tending their own nest or going to rob the nest of another bird.
The page saysit may have declined at first as eastern forests were cleared, before it adapted to nesting in cities
The source saysThe Blue Jay may have declined initially with the clearing of eastern forests, before it adapted to nesting in cities.
The page saysAudubon calls the blue jay intelligent and adaptable
The source saysIntelligent and adaptable
The page saysA blue jay can do a remarkable imitation of the scream of a Red-shouldered Hawk
The source saysthey can do a remarkable imitation of the scream of a Red-shouldered Hawk

Source
02

AnAge: The Animal Ageing and Longevity Database, Build 15, Human Ageing Genomic Resources

AnAge entry for Cyanocitta cristata. AnAge: The Animal Ageing and Longevity Database, Build 15, Human Ageing Genomic Resources.

The page saysThe record for a wild jay is 18.3 years
The source saysRecord longevity in the wild is 18.3 years
The page saysOne captive female lived to 26.2 years
The source saysOne captive female lived 26.2 years

Source
03

Frysinger

Frysinger. Cyanocitta cristata (blue jay). Animal Diversity Web, University of Michigan.

The page sayssouthern Canada and the United States east of the Rocky Mountains
The source saysThey are common in southern Canada and in the United States, east of the Rocky Mountains.Note: stats.habitat; range

Source
04

Darley-Hill & Johnson 1981

Darley-Hill & Johnson (1981). Acorn dispersal by the blue jay (Cyanocitta cristata). Oecologia.

The page saysblue jays cached 133,000 acorns from one stand of oaks
The source saysBlue jays transported and cached 133,000 acorns from a stand of Quercus palustris trees in Blacksburg, VirginiaNote: tagline; Quercus = oak genus
The page saysJays carried one to five nuts per trip, 2.2 on average
The source saysThe number of nuts transported per caching trip ranged from 1-5 with a mean of 2.2.
The page saysthe caches lay a mean 1.1 km from the seed trees (100 m to 1.9 km)
The source saysMean distance between seed trees and caches was 1.1 km (range: 100 m-1.9 km).
The page saysEach nut was cached singly and covered with debris
The source saysNuts were cached singly within a few meters of each other and were always covered with debris.
The page saysjays facilitate colonization by members of the Fagaceae
The source saysblue jays facilitate colonization of members of the Fagaceae
The page saysthe plant family that includes oaks and beeches
The source saysQuercus palustris, Q. phellos, Q. velutina, Fagus grandifoliaNote: definition: the study names Quercus (oak) and Fagus (beech) species among the Fagaceae it treats
The page saysblue jays transported and cached 133,000 acorns, which was 54% of the stand's total mast crop
The source saysBlue jays transported and cached 133,000 acorns from a stand of Quercus palustris trees in Blacksburg, Virginia, representing 54% of the total mast crop.
The page saysStashing 133,000 acorns
The source saysBlue jays transported and cached 133,000 acornsNote: heading
The page saysA Virginia study looked at one stand of oak trees
The source saysfrom a stand of Quercus palustris trees in Blacksburg, VirginiaNote: Quercus = oak genus; acorns named in the same sentence
The page saysJays also ate a further 20% of the stand's acorns where they collected them
The source saysA further 20% (49,000) of the mast crop was eaten by jays at the collecting site.

Source
05

Jones & Kamil 1973

Jones & Kamil (1973). Tool-Making and Tool-Using in the Northern Blue Jay. Science.

The page sayslaboratory-raised jays tore pieces from newspaper pages and used them as tools to rake in food pellets that were otherwise out of reach
The source saysLaboratory-raised Northeirn blue jays (Cyanocitta cristata) have been observed tearing pieces from pages of newspaper and utilizing them as tools to rake in food pellets which were otherwise out of reach.Note: quote keeps the abstract's typo 'Northeirn'
The page saysHow often they did it depended on the jay's motivational state and on whether pellets were there
The source saysThe frequency of this behavior was dependenit upon the motivational state of the jay and the presence of food pellets.Note: quote keeps the abstract's typo 'dependenit'
The page saystags: tool-user
The source saysLaboratory-raised Northeirn blue jays (Cyanocitta cristata) have been observed tearing pieces from pages of newspaper and utilizing them as tools to rake in food pellets which were otherwise out of reach.Note: Captive birds; ADW agrees: 'Blue jays in captivity have been known to fashion tools in order to get at foods.'

Source
06

Pietrewicz & Kamil 1979

Pietrewicz & Kamil (1979). Search Image Formation in the Blue Jay (Cyanocitta cristata). Science.

The page saysjays trained to spot Catocala moths in slides improved over successive encounters when a series showed one species
The source saysBlue jays trained to detect Catocala moths in slides were exposed to two types of slide series containing these moths: series of one species and series of two species intermixed. In one-species series, detection ability increased with successive encounters with one prey type.
The page saysa direct demonstration of a specific search image
The source saysThese results are a direct demonstration of a specific search image.
The page saysNo similar effect occurred when two species were mixed
The source saysNo similar effect occurred in two-species series.

Source
07

The IUCN Red List of Threatened Species 2025

Cyanocitta cristata. The IUCN Red List of Threatened Species 2025: e.T22705611A137739324.

The page saysLeast Concern
The source saysIUCN Red List category: Least Concern (LC).Note: stats.conservationStatus
The page saysThe IUCN Red List rates the blue jay 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.