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What the sources say

SwordfishXiphias gladius

Every figure, record and mechanism on the Swordfish profile was written from a source, and this is the working table behind it: 36 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

Collette et al. 2022

Collette et al. (2022). Xiphias gladius. The IUCN Red List of Threatened Species 2022: e.T23148A46625751.

The page saysThe IUCN Red List rates the swordfish Near Threatened
The source saysIUCN Red List category: Near Threatened (NT).
The page saysNear Threatened
The source saysIUCN Red List category: Near Threatened (NT).

Source
02

Florida Museum of Natural History, Discover Fishes

Swordfish (Xiphias gladius). Florida Museum of Natural History, Discover Fishes.

The page saysSwordfish are believed to swim down to 2,100 feet (650 m) or deeper, where the water may be just above freezing
The source saysit is believed to swim to depths of 2,100 feet (650 m) or greater, where the water temperature may be just above freezing
The page saysa large bundle of tissue associated with one of the eye muscles
The source saysa “brain heater,” a large bundle of tissue associated with one of the eye muscles, which insulates and warms the brain
The page saysA female swordfish may carry from 1 million to 29 million eggs, and estimates vary a lot
The source saysEstimates vary considerably, but females may carry from 1 million to 29 million eggs in their gonads
The page saysThe bill is long, even for a billfish
The source saysThe bill is long relative to other billfishes
The page saysAdults have no teeth and no scales
The source saysAdults lack scales and teeth
The page saysYoung swordfish have scales, but they lose them by about 3 feet (1 m) long
The source saysWhile the young have scales, these are lost by the time the fish attain a body length of about 3 feet (1 m)
The page saysSwordfish feed mostly on pelagic fishes (fish of the open sea) and occasionally on squid
The source saysThey feed mostly upon pelagic fishes, and occasionally squids and other cephalopods
The page saysSquid and cuttlefish pulled from swordfish stomachs often carry slashes
The source sayssquid and cuttlefishes commonly exhibit slashes to the body when taken from swordfish stomachs
The page saysin one study most large fish prey had been slashed, while small prey were eaten whole
The source saysA recent study found the majority of large fish prey had been slashed, while small prey items had been consumed whole
The page saysSwordfish reach a maximum of 177 inches (455 cm) and 1,400 pounds (650 kg)
The source saysSwordfish reach a maximum size of 177 in. (455 cm) total length and a maximum weight of 1,400 lbs. (650 kg)
The page saysNearly all of those over 300 pounds (140 kg) are female
The source saysnearly all specimens over 300 lbs. (140 kg) are female
The page saysSwordfish live in the Atlantic, Pacific and Indian Oceans, from about 60 degrees north to 45 degrees south
The source saysfound in oceanic regions worldwide, including the Atlantic, Pacific, and Indian Oceans ... with a latitudinal range of approximately 60°N to 45°S
The page saysThey migrate, generally moving to warmer water in winter and cooler water in summer
The source sayshighly migratory species, generally moving to warmer waters in the winter and cooler waters in the summer
The page saysthey often turn up in frontal zones, where ocean currents collide and productivity is high
The source saysIt is often present in frontal zones, areas where ocean currents collide and productivity is high
The page saysYes. Of all the billfish, the swordfish has the widest temperature tolerance, and it turns up in water from 41 to 80 degrees F (5 to 27 degrees C)
The source saysthe swordfish has the widest temperature tolerance of any billfish, and can be found in waters from 41-80°F (5-27°C)
The page saysIt is mainly a warm-water fish, but its brain heater helps it swim in cold depths
The source saysAlthough mainly a warm-water species ... One adaptation which allows for swimming in such cold water is the presence of a “brain heater,”
The page saysOpen oceans worldwide, in tropical, temperate and sometimes cold waters
The source saysfound in oceanic regions worldwide ... It is found in tropical, temperate, and sometimes cold waters
The page saysMostly pelagic fish, and some squid
The source saysThey feed mostly upon pelagic fishes, and occasionally squids and other cephalopods
The page saysA fish with a heater for its brain and a flattened bill it apparently uses to slash prey
The source saysa “brain heater,” a large bundle of tissue associated with one of the eye muscles ... appears as a flattened oval in cross section ... The sword is apparently used in obtaining prey, as squid and cuttlefishes commonly exhibit slashes to the body
The page saysin cross section it appears as a flattened oval
The source saysits prolonged “bill”, which appears as a flattened oval in cross section
The page saysPredators of adult swordfish include killer whales
The source saysPredators of adult swordfish include marine mammals such as killer whales
The page saysSwordfish also host 49 species of parasites, from tapeworms in the gut to flukes on the gills
The source saysSwordfish are hosts to 49 species of parasites including cestodes (tapeworms) in the stomach and intestines, nematodes (roundworms) in the stomach, tremodes (flukes) on the gills
The page saysOne adaptation that lets them swim in such cold water is a "brain heater"
The source saysOne adaptation which allows for swimming in such cold water is the presence of a “brain heater,”
The page saysThe sword is apparently used to catch prey
The source saysThe sword is apparently used in obtaining prey
The page saysone adaptation that lets it swim in depths where the water may be just above freezing
The source sayswhere the water temperature may be just above freezing. One adaptation which allows for swimming in such cold water is the presence of a “brain heater,”

Source
03

NOAA Fisheries

North Atlantic Swordfish. NOAA Fisheries.

The page saysThe ones caught by the North Atlantic fishery average 50 to 200 pounds
The source saysthe average size caught in the fishery is 50 to 200 pounds
The page saysNOAA says North Atlantic swordfish live about 9 years
The source saysSwordfish live about 9 years
The page saysNOAA calls Atlantic swordfish one of the fastest predators in the ocean and says their streamlined bodies let them swim at speeds of up to 50 mph
The source saysAtlantic swordfish are one of the fastest predators in the ocean. Their streamlined body allows them to swim at high speeds, up to 50 mph
The page saysFemales there can reproduce between 4 and 5 years of age
The source saysFemales are able to reproduce between 4 and 5 years of age

Source
04

Fritsches, Brill & Warrant 2005

Fritsches, Brill & Warrant (2005). Warm eyes provide superior vision in swordfishes. Current Biology.

The page saysIt warms the eyes and brain up to 10 to 15 degrees C above the water around them
The source saysa highly specialized heating system located in an extraocular muscle specifically warms the eyes and brain up to 10 degrees C-15 degrees C above ambient water temperatures
The page saysin fast-swimming predatory fish such as the swordfish, warming the retina improves temporal resolution, and so the detection of rapid motion
The source sayswarming the retina significantly improves temporal resolution, and hence the detection of rapid motion, in fast-swimming predatory fishes such as the swordfish
The page saysDepending on dive depth, it can be more than ten times higher in these fish than in fishes whose eyes match the water temperature
The source saysDepending on diving depth, temporal resolution can be more than ten times greater in these fishes than in fishes with eyes at the same temperature as the surrounding water
The page saysA heating tissue in one of its eye muscles that warms the brain and eyes up to 10 to 15 degrees C above the water
The source saysa highly specialized heating system located in an extraocular muscle specifically warms the eyes and brain up to 10 degrees C-15 degrees C above ambient water temperatures
The page saysA swordfish's warmed eyes can resolve rapid motion more than ten times better than fish eyes at water temperature, depending on dive depth.
The source saysDepending on diving depth, temporal resolution can be more than ten times greater in these fishes than in fishes with eyes at the same temperature as the surrounding waterNote: vibe.reason

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.