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What the sources say

North Island Brown KiwiApteryx mantelli

Every figure, record and mechanism on the North Island Brown Kiwi 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

Smithsonian's National Zoo and Conservation Biology Institute

North Island brown kiwi. Smithsonian's National Zoo and Conservation Biology Institute.

The page saysnostrils near the tip
The source saysThe kiwi's long, curved, pale gray-brown bill is unique in the bird world in having the nostrils located near the tip.
The page saysA kiwi plunges that bill again and again into the leaf litter of the forest floor.
The source saysthe bird forages by plunging it repeatedly into the leaf litter of the forest floor in search of prey
The page saysIt often snuffles audibly as it searches, a sound that may come from a valve behind the nostrils that stops it inhaling dirt.
The source saysoften snuffle audibly when searching for food. The snuffling may be produced by the opening and closing of a valve behind the nostrils that prevents the bird from inhaling dirt and debris
The page saysA female kiwi lays an extremely large egg, an average of 15 percent of her body weight. It weighs about 450 grams and is over 60 percent yolk.
The source saysThe female lays a single extremely large egg — an average of 15 percent of her body weight. Producing such a large (about 1 pound) and energy-rich (over 60 percent yolk) eggsNote: task #986: the source gives "about 1 pound"; 1 lb is 454 g, stated in grams to match the metric body
The page saysKiwi are stout birds that stand 0.5 to 0.6 metres tall.
The source saysKiwi are stout birds, standing 1.5 to 2 feet tall (0.5 to 0.6 meters) tallNote: Smithsonian text is for kiwi; kept scoped to kiwi
The page saysFemales are heavier than males, at 2 to 3.9 kilograms against 1.4 to 3.2 kilograms.
The source saysfemales at 4.5 to 8.5 pounds (2 to 3.9 kilograms) weighing more than males at 3 to 7 pounds (1.4 to 3.2 kilograms)
The page saysearthworms, beetles, snails, crayfish, insects, fruits and berries
The source saysBrown kiwi have an extremely varied diet that includes earthworms, beetles, snails, crayfish, insects, fruits and berries.
The page saysKiwi forage actively from dusk to dawn.
The source saysKiwi are nocturnal birds. They forage actively from dusk to dawn.
The page saysA territory covers 5 to 50 hectares depending on habitat quality, and each one holds several burrows.
The source saysTerritories range in size from 12 to 124 acres (5 to 50 hectares) depending on the quality of the habitat. Kiwi excavate several burrows within each territory.
The page saysshe leaves the male to incubate the eggs, which takes about 68 to 91 days
The source saysShe then leaves the male to incubate the eggs, which takes about 68 to 91 days.
The page saysAdults are usually feisty enough to defend themselves against smaller predators, but eggs and newly hatched young are very vulnerable.
The source saysadult kiwi are usually feisty enough to defend themselves against the smaller predators, their eggs and newly hatched young are extremely vulnerable to predation.
The page saysPredators include rats, weasels, cats, dogs and pigs.
The source saysPredators include rats, weasels, cats, dogs and pigs.
The page saysNostrils near the tip of a long, curved bill
The source saysThe kiwi's long, curved, pale gray-brown bill is unique in the bird world in having the nostrils located near the tip.
The page saysA flightless night forager with its nostrils near the tip of its bill
The source saysKiwi are flightless, nocturnal birds native only to New Zealand.
The page saysWith its feet. A kiwi chick has no egg tooth and kicks its way out of the shell.
The source saysKiwi chicks have no egg tooth and must use their feet to kick their way out of the shell.
The page saysIt hatches fully developed and looks like a miniature adult.
The source saysThey are fully developed chicks, looking like a miniature replica of an adult.
The page saysMost kiwi species are independent by four weeks of age, but the birds do not reach adult size until they are 18 to 20 months old.
The source saysAlthough most species are completely independent by four weeks of age, they do not reach adult size until they are 18 to 20 months old.
The page saysTheir eyes are small, while their ears are unusually large.
The source saysThough their eyes are small, their ears are unusually large.
The page saysan egg that averages 15 percent of its mother's weight
The source saysThe female lays a single extremely large egg — an average of 15 percent of her body weight.
The page saysIts long, curved bill is unique in the bird world in having the nostrils near the tip.
The source saysThe kiwi's long, curved, pale gray-brown bill is unique in the bird world in having the nostrils located near the tip.
The page saysA female kiwi lays an extremely large egg, an average of 15 percent of her body weight.
The source saysThe female lays a single extremely large egg — an average of 15 percent of her body weight.
The page saysThe North Island brown kiwi (Apteryx mantelli) is a flightless bird that forages at night.
The source saysKiwi are flightless, nocturnal birds native only to New Zealand.
The page saysKiwi use that bill to sniff out food.
The source saysThey use their unique bill to sniff out food
The page saysA kiwi snuffles audibly as it hunts, a sound that may come from a valve behind its nostrils
The source saysoften snuffle audibly when searching for food. The snuffling may be produced by the opening and closing of a valve behind the nostrils that prevents the bird from inhaling dirt and debrisNote: vibe.reason

Source
02

New Zealand Department of Conservation

Brown kiwi. New Zealand Department of Conservation.

The page saysEvery brown kiwi lives on New Zealand's North Island, in lowland and coastal native forest and subalpine areas.
The source saysAll brown kiwi live in the North Island.
The page sayslowland and coastal native forest and subalpine areas
The source saysFound in: Lowland and coastal native forest and subalpine areas in the North Island
The page saysThere are four distinct forms: the Northland, Coromandel, Western and Eastern brown kiwi.
The source saysFour geographically and genetically distinct forms have been identified: Northland brown kiwi Coromandel brown kiwi Western brown kiwi Eastern brown kiwi.
The page saysNew Zealand's Department of Conservation says other kiwi live to be 40 to 65 years old, but the Northland form of this species averages only 14 years.
The source saysOther kiwi live to be 40-65 years old, but the Northland brown kiwi averages only 14 years.
The page saysBrown kiwi breed faster than other kiwi, with up to two eggs a clutch and one to two clutches a year.
The source saysThe brown kiwi is faster at breeding than other kiwi, producing up to two eggs a clutch, and one to two clutches a year
The page saysA 1996 estimate said North Island kiwi had probably declined by at least 90% over the previous century
The source saysIn 1996, it was estimated that North Island kiwi had probably declined by at least 90% during the previous century.
The page saysthe Department of Conservation puts the population at about 26,000
The source saysThreat status: Not Threatened (conservation dependent) Population: About 26,000
The page saysLowland and coastal native forest and subalpine areas of New Zealand's North Island
The source saysLowland and coastal native forest and subalpine areas in the North Island
The page saysEven so, numbers are falling.
The source saysmuch of that good reproductive work is undone by the ravages of dogs, stoats, and loss of habitat
The page saysEven so, numbers are falling.
The source saysthe population is steadily declining

Source
03

Butler & McLennan

Butler & McLennan. Kiwi Recovery Plan. New Zealand Department of Conservation, Threatened Species Recovery Plan Series No. 2.

The page saystags: insectivore
The source saysEarthworms, cicada nymphs and beetle adults and larvae are their main foods, supplemented by a few seeds and leaves and a wide variety of other invertebratesNote: tags, task #986: grubs and insects are the main foods and plants 'a few', so insectivore stands; omnivore's 'plant matter, fruits, insects, and meat' overstates the plant share

Source
04

Corfield et al. 2014

Corfield et al. (2014). Anatomical Specializations for Enhanced Olfactory Sensitivity in Kiwi, Apteryx mantelli. Brain, Behavior and Evolution.

The page saysScientists compared kiwi with 55 other bird species, and the kiwi's olfactory bulbs
The source sayswe examine the size of the olfactory bulbs in kiwi and compare them with 55 other bird species
The page sayswere proportionately larger than any other bird's in the study
The source saysKiwi were a clear outlier in our analysis, with olfactory bulbs that are proportionately larger than those of any other bird in this study.

Source
05

Cunningham, Castro & Alley 2007

Cunningham, Castro & Alley (2007). A new prey-detection mechanism for kiwi (Apteryx spp.) suggests convergent evolution between paleognathous and neognathous birds. Journal of Anatomy.

The page saysThe bill tip holds mechanoreceptors, cells that sense vibration and pressure, set in pits arranged like those of sandpipers and snipe. A kiwi may be able to locate prey the same way.
The source saysApteryx possess an arrangement of mechanoreceptors within pits similar to that in Scolopacidae species and may therefore be able to localise prey using a similar vibrotactile sense.
The page saysTouch may help too.
The source saysmay therefore be able to localise prey using a similar vibrotactile sense

Source
06

Martin et al. 2007

Martin et al. (2007). Kiwi Forego Vision in the Guidance of Their Nocturnal Activities. PLoS ONE.

The page saysA study of kiwi eye structure, visual field and brain found minimal reliance on vision and more reliance on touch and smell.
The source saysKiwi show minimal reliance upon vision indicated by eye structure, visual field topography, and brain structures, and increased reliance upon tactile and olfactory information.
The page saysSight is not their main tool.
The source saysKiwi show minimal reliance upon vision

Source
07

Taborsky & Taborsky 1991

Taborsky & Taborsky (1991). Social Organization of North Island Brown Kiwi: Long-term Pairs and Three Types of Male Spacing Behaviour. Ethology.

The page saysIn one radio-tracking study of 51 North Island brown kiwi in Waitangi State Forest, behavioural evidence suggested long-term pairs.
The source saysWe observed 51 kiwi by radiotracking for an average period of 2.3 months each, in Waitangi State Forest, New Zealand. ... behavioural evidence suggests a monogamous mating system with long‐term pair bonds.
The page says22.1% of fully grown males in 1986 and 37.3% in 1987 had no mate.
The source saysA surplus of fully grown males (22.1% in 1986, 37.3% in 1987) remained unpaired.

Source
08

The IUCN Red List of Threatened Species 2017

Apteryx mantelli. The IUCN Red List of Threatened Species 2017: e.T45353580A119177586.

The page saysThe IUCN Red List rates the species Vulnerable.
The source saysIUCN Red List category: Vulnerable (VU).
The page saysVulnerable
The source saysIUCN Red List category: Vulnerable (VU).

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.