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What the sources say

Bottlenose DolphinTursiops truncatus

Every figure, record and mechanism on the Bottlenose Dolphin profile was written from a source, and this is the working table behind it: 39 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

NOAA Fisheries

Common Bottlenose Dolphin. NOAA Fisheries.

The page says6 to 13 feet long and weigh 300 to 1,400 pounds
The source saysWeight 300 to 1,400 pounds Length 6 to 13 feet
The page saysNOAA Fisheries says they can live at least 40 years, with some females outliving males at 60 years or more.
The source saysBottlenose dolphins can live at least 40 years, with some females outliving males at 60 years or more.
The page saysFemales as old as 45 have given birth
The source saysFemales as old as 45 have given birth.
The page saysNOAA lists bottlenose dolphins as likely to go through menopause, like humans, killer whales, belugas and narwhals
The source saysspecies known to undergo menopause include humans, short-finned pilot whales, narwhals, beluga whales, killer whales, false killer whales, and likely, bottlenose dolphins
The page saysThey feed on a variety of prey, such as fish, squid, and crustaceans like crabs and shrimp.
The source saysfeed on a variety of prey, such as fish, squid, and crustaceans (e.g., crabs and shrimp)
The page saysThey may work together to herd fish into groups and take turns charging through the school, or trap schools of fish against sandbars and seawalls for an easy meal.
The source sayssearching for food individually or cooperatively. For example, they work together to herd fish into groups and then take turns charging through the school of fish to feed. Bottlenose dolphins may also trap schools of fish against sand bars and seawalls for an easy meal.
The page saysThey do not chew: a dolphin grips a fish in its teeth and swallows it whole, head first, so the spines do not catch in its throat
The source saysInstead of using their teeth to chew, bottlenose dolphins grip fish with their teeth, then swallow the fish whole—head first—so the spines of the fish don't catch in their throats.
The page saysTo find prey, they use passive listening, high-frequency echolocation, or both.
The source saysThey use passive listening and/or high frequency echolocation to locate prey.
The page saysTemperate and tropical waters worldwide, from harbors, bays and estuaries to far offshore in the open ocean
The source saysBottlenose dolphins are found in temperate and tropical waters around the world. They inhabit a wide variety of habitats, including harbors, bays, gulfs, and estuaries, as well as nearshore coastal waters, deeper waters over the continental shelf, and even far offshore in the open ocean.
The page saysA variety of prey such as fish, squid, crabs and shrimp, with fish sometimes herded into groups or trapped against sandbars and seawalls
The source saysfeed on a variety of prey, such as fish, squid, and crustaceans (e.g., crabs and shrimp). ... they work together to herd fish into groups ... Bottlenose dolphins may also trap schools of fish against sand bars and seawalls for an easy meal.
The page saysBottlenose dolphins are found in temperate and tropical waters around the world, from harbors, bays and estuaries to far offshore in the open ocean
The source saysBottlenose dolphins are found in temperate and tropical waters around the world. They inhabit a wide variety of habitats, including harbors, bays, gulfs, and estuaries, as well as nearshore coastal waters, deeper waters over the continental shelf, and even far offshore in the open ocean.

Source
02

Animal Diversity Web, University of Michigan

Tursiops truncatus (bottlenosed dolphin). Animal Diversity Web, University of Michigan.

The page saysEach dolphin is believed to keep its own signature whistle for life
The source saysEach dolphin is believed to possess its own signature whistle and, once it is developed, it is retained for the duration of the dolphin's life.Note: tagline, first half
The page saysadult males typically grow bigger than adult females
The source saysAdult males are usually between 244 and 381 cm long, and weigh about 500 kg. Adult females are typically between 228 and 366 cm, and weigh about 250 kg. ... Sexual Dimorphism male larger
The page saysLarger sharks, such as bull, tiger, and dusky sharks, are their most common predators, and these sharks prey on smaller dolphins, calves and females more than larger dolphins
The source saysThe most common predators of bottlenosed dolphins are larger sharks, such as bull (Carcharhinus leucas), tiger (Galeocerdo cuvier), and dusky sharks (Carcharhinus obscurus). These sharks prey on smaller dolphins, calves and female dolphins more than larger dolphins.
The page saysIt is not uncommon to see dolphins bearing shark bites, proof they survived an attack.
The source saysIt is not uncommon to observe dolphins with shark bites, demonstrating their survival of an attack.
The page saysBlubber may give some protection against predators.
The source saysBlubber may provide some protection against predators.
The page saysEach dolphin is believed to have its own signature whistle and to keep it for life, and calves can develop one as young as one month old
The source saysEach dolphin is believed to possess its own signature whistle and, once it is developed, it is retained for the duration of the dolphin's life. ... Signature whistles develop in calves as young as one month
The page saysHalf its brain rests at a time.
The source saysIt turns out that they rest one side of their brains while decreasing their activity level.Note: the blockquote's bold lead-in
The page saysA dolphin has to surface to breathe, and it sleeps by resting one side of its brain while lowering its activity level.
The source saysOne may wonder how dolphins, as marine animals that must surface to breathe every few minutes, sleep. It turns out that they rest one side of their brains while decreasing their activity level.
The page saysThat lets it rest yet stay conscious enough to breathe and carry on basic survival behaviors.
The source saysThis allows them rest and yet remain 'conscious' to breathe and carry on basic survival behaviors.
The page saysEcholocation calls pass through the melon, a fatty lens for sound that focuses the outgoing calls, while a fatty pad in the lower jaw focuses sound to each ear.
The source saysEcholocation calls pass through the melon and intramandibular fat body, which contain acoustic lipids; these structures serve as acoustic lenses to focus sound. The intramandibular fat bodies focus sound to each ear, while the melon is used as a lens to focus outgoing sound.
The page saysDolphins use echolocation to navigate and to detect the shape of the seafloor, prey and the presence of predators.
The source saysBottlenosed dolphins also navigate with echolocation, used to detect bottom topography, prey, and the presence of predators.
The page saysA bottlenose dolphin rests one half of its brain at a time while lowering its activity level. That keeps it conscious enough to breathe and carry on other basic survival behavior even while it rests.
The source saysIt turns out that they rest one side of their brains while decreasing their activity level. This allows them rest and yet remain 'conscious' to breathe and carry on basic survival behaviors.
The page saysThe melon is a fatty lens for sound that focuses the outgoing calls a dolphin makes for echolocation, while a fatty pad in its lower jaw focuses sound to each ear.
The source saysEcholocation calls pass through the melon and intramandibular fat body, which contain acoustic lipids; these structures serve as acoustic lenses to focus sound. The intramandibular fat bodies focus sound to each ear, while the melon is used as a lens to focus outgoing sound.
The page saysDolphins use echolocation to detect prey, the shape of the seafloor, and predators.
The source saysBottlenosed dolphins also navigate with echolocation, used to detect bottom topography, prey, and the presence of predators.

Source
03

Wells, Natoli & Braulik 2019

Wells, Natoli & Braulik (2019). Tursiops truncatus. The IUCN Red List of Threatened Species 2019: e.T22563A156932432.

The page saysLeast Concern
The source saysIUCN Red List category: Least Concern (LC).

Source
04

Janik & Slater 1998

Janik & Slater (1998). Context-specific use suggests that bottlenose dolphin signature whistles are cohesion calls. Animal Behaviour.

The page saysA 1998 study of four captive dolphins found that each one mainly made its own signature whistle when it was apart from the group, strong support for the idea that the whistle keeps the group together
The source sayswe examined whistle type usage in a group of four captive bottlenose dolphins in two contexts. ... Each dolphin primarily produced one stereotyped signature whistle when it was separated from the group. ... The results strongly support the hypothesis that signature whistles are used to maintain group cohesion.Note: the year 1998 is the reference's publication year, not text inside the abstract
The page saysStudies of captive bottlenose dolphins have shown that each one produces its own individually specific signature whistle.
The source saysStudies on captive bottlenose dolphins, Tursiops truncatus, have shown that each individual produces a stereotyped, individually specific signature whistle
The page saysA 1998 study of four captive dolphins found that each mainly made its own signature whistle when it was apart from the group, and almost only other whistles when all four shared a pool.
The source saysa group of four captive bottlenose dolphins ... Each dolphin primarily produced one stereotyped signature whistle when it was separated from the group. ... If all animals swam in the same pool almost only nonsignature whistles were used.Note: the year 1998 is the reference's publication year, not text inside the abstract
The page saysThat strongly supports the idea that signature whistles help keep a group together.
The source saysThe results strongly support the hypothesis that signature whistles are used to maintain group cohesion.

Source
05

Janik, Sayigh & Wells 2006

Janik, Sayigh & Wells (2006). Signature whistle shape conveys identity information to bottlenose dolphins. Proceedings of the National Academy of Sciences.

The page saysIn a 2006 study, dolphins could still tell whose signature whistle they were hearing after researchers removed all its voice features.
The source saysThis study demonstrates that bottlenose dolphins extract identity information from signature whistles even after all voice features have been removed from the signal.Note: the year 2006 is the reference's publication year, not text inside the abstract
The page saysAt the time, dolphins were the only animals other than humans shown to pass on identity information independent of the caller's voice.
The source saysThus, dolphins are the only animals other than humans that have been shown to transmit identity information independent of the caller's voice or location.Note: dated to the 2006 paper because it states a record, and the source is from 2006
The page saysIn a 2006 study, dolphins could still tell whose signature whistle they were hearing after researchers removed all its voice features.
The source saysbottlenose dolphins extract identity information from signature whistles even after all voice features have been removed from the signalNote: FAQ 3; the year 2006 is the reference's publication year
The page saysAt the time, dolphins were the only animals other than humans shown to pass on identity information independent of the caller's voice.
The source saysdolphins are the only animals other than humans that have been shown to transmit identity information independent of the caller's voice or locationNote: FAQ 3; dated to the 2006 paper because it states a record
The page saysA signature whistle other dolphins can recognize even with its voice features removed, plus echolocation focused through a fatty lens for sound to find prey and read the seafloor.
The source saysbottlenose dolphins extract identity information from signature whistles even after all voice features have been removed from the signalNote: superpower; the melon-as-lens and prey and seafloor detection in the second half are covered by the adw-tursiops-truncatus claims on the body and FAQ 4

Source
06

Janik 2000

Janik (2000). Whistle Matching in Wild Bottlenose Dolphins (Tursiops truncatus). Science.

The page saysWild dolphins also answer another dolphin's whistle by making the same whistle type, over distances of up to 580 meters, a sign of animals addressing each other individually
The source sayswild, unrestrained bottlenose dolphins use their learned whistles in matching interactions, in which an individual responds to a whistle of a conspecific by emitting the same whistle type. Vocal matching occurred over distances of up to 580 meters and is indicative of animals addressing each other individually.
The page saysfor an animal that answers another dolphin's whistle by making the same whistle type
The source saysan individual responds to a whistle of a conspecific by emitting the same whistle typeNote: vibe.reason; the words before "for" describe the track, and the song is "Wannabe" by the Spice Girls (re-paired in #877)

Source
07

Plotnik, de Waal & Reiss 2006

Plotnik, de Waal & Reiss (2006). Self-recognition in an Asian elephant. Proceedings of the National Academy of Sciences.

The page saysdolphins have passed the mirror test for self-recognition
The source saysAfter the recent discovery of MSR in dolphins (Tursiops truncatus)Note: tagline, second half
The page saysDolphins have also passed the mirror test for self-recognition, which had long seemed limited to humans and apes, and that discovery made elephants the next logical species to test
The source saysmirror self-recognition (MSR) has long seemed limited to humans and apes. ... After the recent discovery of MSR in dolphins (Tursiops truncatus), elephants thus were the next logical candidate species.

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.