Bottlenose dolphins are

aquatic mammals Aquatic and semiaquatic mammals are a diverse group of mammals that dwell partly or entirely in bodies of water. They include the various marine mammals who dwell in oceans, as well as various freshwater species, such as the European otter. The ...

in the genus ''Tursiops.'' They are common,

cosmopolitan Cosmopolitan may refer to: Food and drink * Cosmopolitan (cocktail), also known as a "Cosmo" History * Rootless cosmopolitan, a Soviet derogatory epithet during Joseph Stalin's anti-Semitic campaign of 1949–1953 Hotels and resorts * Cosmopoli ...

members of the family

Delphinidae Oceanic dolphins or Delphinidae are a widely distributed family of dolphins that live in the sea. Close to forty extant species are recognised. They include several big species whose common names contain "whale" rather than "dolphin", such as the ...

, the family of oceanic

dolphin A dolphin is an aquatic mammal within the infraorder Cetacea. Dolphin species belong to the families Delphinidae (the oceanic dolphins), Platanistidae (the Indian river dolphins), Iniidae (the New World river dolphins), Pontoporiidae (the ...

s. Molecular studies show the genus definitively contains two

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

: the

common bottlenose dolphin The common bottlenose dolphin or Atlantic bottlenose dolphin (''Tursiops truncatus'') is a wide-ranging marine mammal of the family Delphinidae. The common bottlenose dolphin is a very familiar dolphin due to the wide exposure it gets in captiv ...

(''Tursiops truncatus'') and the

Indo-Pacific bottlenose dolphin The Indo-Pacific bottlenose dolphin (''Tursiops aduncus'') is a species of bottlenose dolphin. This dolphin grows to long, and weighs up to . It lives in the waters around India, northern Australia, South China, the Red Sea, and the eastern ...

(''Tursiops aduncus''). Others, like the

Burrunan dolphin The Burrunan dolphin (''Tursiops australis'') is a species of bottlenose dolphin found in parts of Victoria, Australia first described in 2011. Its exact taxonomy is debated: numerous studies support it as being a separate species within the genu ...

(''Tursiops (aduncus) australis''), may be alternately considered their own species or be subspecies of ''T. aduncus''. Bottlenose dolphins inhabit warm and

temperate In geography, the temperate climates of Earth occur in the middle latitudes (23.5° to 66.5° N/S of Equator), which span between the tropics and the polar regions of Earth. These zones generally have wider temperature ranges throughout ...

seas worldwide, being found everywhere except for the

Arctic The Arctic ( or ) is a polar region located at the northernmost part of Earth. The Arctic consists of the Arctic Ocean, adjacent seas, and parts of Canada (Yukon, Northwest Territories, Nunavut), Danish Realm (Greenland), Finland, Iceland, N ...

and

Antarctic Circle The Antarctic Circle is the most southerly of the five major circles of latitude that mark maps of Earth. The region south of this circle is known as the Antarctic, and the zone immediately to the north is called the Southern Temperate Zone. So ...

regions. Their name derives from the Latin ''tursio'' (dolphin) and ''truncatus'' for their characteristic truncated teeth. Numerous investigations of bottlenose dolphin intelligence have been conducted, examining mimicry, use of

artificial language Artificial languages are languages of a typically very limited size which emerge either in computer simulations between artificial agents, robot interactions or controlled psychological experiments with humans. They are different from both constr ...

, object categorization, and

self-recognition In philosophy of self, self-awareness is the experience of one's own personality or individuality. It is not to be confused with consciousness in the sense of qualia. While consciousness is being aware of one's environment and body and lifesty ...

. They can use tools (sponging; using marine sponges to forage for food sources they normally could not access) and transmit cultural knowledge from generation to generation, and their considerable intelligence has driven interaction with humans. Bottlenose dolphins gained popularity from aquarium shows and television programs such as '' Flipper''. They have also been trained by militaries to locate

sea mine A naval mine is a self-contained explosive device placed in water to damage or destroy surface ships or submarines. Unlike depth charges, mines are deposited and left to wait until they are triggered by the approach of, or contact with, any v ...

s or detect and mark enemy divers. In some areas, they cooperate with local fishermen by driving fish into their nets and eating the fish that escape. Some encounters with humans are harmful to the dolphins: people hunt them for food, and dolphins are killed inadvertently as a bycatch of

tuna A tuna is a saltwater fish that belongs to the tribe Thunnini, a subgrouping of the Scombridae ( mackerel) family. The Thunnini comprise 15 species across five genera, the sizes of which vary greatly, ranging from the bullet tuna (max len ...

fishing and by getting caught in crab traps. Bottlenose dolphins have the third largest

encephalization Encephalization quotient (EQ), encephalization level (EL), or just encephalization is a relative brain size measure that is defined as the ratio between observed to predicted brain mass for an animal of a given size, based on nonlinear regressi ...

levels of any mammal on Earth (humans have the largest, followed by Northern Right whale dolphins), sharing close ratios with those of

human Humans (''Homo sapiens'') are the most abundant and widespread species of primate, characterized by bipedalism and exceptional cognitive skills due to a large and complex brain. This has enabled the development of advanced tools, cultu ...

s and other cetaceans, while being twice as high of other

great apes The Hominidae (), whose members are known as the great apes or hominids (), are a taxonomic family of primates that includes eight extant species in four genera: '' Pongo'' (the Bornean, Sumatran and Tapanuli orangutan); ''Gorilla'' (the ...

. This more than likely contributes to their high

intelligence Intelligence has been defined in many ways: the capacity for abstraction, logic, understanding, self-awareness, learning, emotional knowledge, reasoning, planning, creativity, critical thinking, and problem-solving. More generally, it can be des ...

and

emotional intelligence Emotional intelligence (EI) is most often defined as the ability to perceive, use, understand, manage, and handle emotions. People with high emotional intelligence can emotion recognition, recognize their own emotions and those of others, use em ...

Taxonomy

Scientists have been long aware of the fact that the ''Tursiops'' dolphins might consist of more than one species, as there is extensive variation in color and morphology along its range. In the past, most studies used morphology to evaluate differences between and within species, but in the late 20th century, combining morphological and molecular genetics allowed much greater insight into this previously intractable problem. Since the late 1990s and early 2000s, most researchers acknowledged the existence of two species: the

(''T. truncatus''), found in coastal and oceanic habitats of most tropical to temperate oceans, and the

(''T. aduncus''), that lives in coastal waters around

India India, officially the Republic of India (Hindi: ), is a country in South Asia. It is the seventh-largest country by area, the second-most populous country, and the most populous democracy in the world. Bounded by the Indian Ocean on the so ...

, northern Australia, South China, the

Red Sea The Red Sea ( ar, البحر الأحمر - بحر القلزم, translit=Modern: al-Baḥr al-ʾAḥmar, Medieval: Baḥr al-Qulzum; or ; Coptic: ⲫⲓⲟⲙ ⲛ̀ϩⲁϩ ''Phiom Enhah'' or ⲫⲓⲟⲙ ⲛ̀ϣⲁⲣⲓ ''Phiom ǹšari''; ...

, and the eastern coast of Africa. In 2011, a third distinct species was described, the

(''T. (aduncus) australis''), found in the

Port Phillip Port Phillip ( Kulin: ''Narm-Narm'') or Port Phillip Bay is a horsehead-shaped enclosed bay on the central coast of southern Victoria, Australia. The bay opens into the Bass Strait via a short, narrow channel known as The Rip, and is com ...

and

Gippsland Lakes The Gippsland Lakes are a network of coastal lakes, marshes and lagoons in East Gippsland, Victoria, Australia covering an overall area of about between the rural towns of Lakes Entrance, Bairnsdale and Sale. The largest of the lakes are L ...

areas of

Victoria Victoria most commonly refers to: * Victoria (Australia), a state of the Commonwealth of Australia * Victoria, British Columbia, provincial capital of British Columbia, Canada * Victoria (mythology), Roman goddess of Victory * Victoria, Seychelle ...

, Australia, after research showed it was distinct from ''T. truncatus'' and ''T. aduncus'', both in morphology and genetics. Also, evidence has been accumulating to validate the existence of a separate species, Lahille's bottlenose dolphin, ''T. gephyreus'', that occurs in coastal waters of Argentina, Uruguay and southern Brazil. The Society for Marine Mammalogy's Committee on Taxonomy, presently recognizes only two species, ''T. truncatus'' and ''T. aduncus'', and two subspecies: the Black Sea bottlenose dolphin (''T. t. ponticus''), that lives in the

Black Sea The Black Sea is a marginal mediterranean sea of the Atlantic Ocean lying between Europe and Asia, east of the Balkans, south of the East European Plain, west of the Caucasus, and north of Anatolia. It is bounded by Bulgaria, Georgia, Rom ...

, and Lahille's bottlenose dolphin (''T. t. gephyreus''). Other sources also accept the Pacific bottlenose dolphin (''T. t. gillii'' or ''T. gillii''), that inhabits the Pacific, and has a black line from the eye to the forehead. The IUCN, on their

Red List The International Union for Conservation of Nature (IUCN) Red List of Threatened Species, also known as the IUCN Red List or Red Data Book, founded in 1964, is the world's most comprehensive inventory of the global conservation status of biologi ...

of endangered species, also recognises only two species of bottlenose dolphins. The American Society of Mammalogists also recognizes only two species; while acknowledging the studies describing ''T. australis'', it classifies it within ''T. aduncus''. Tursiops aduncus

Much of the discussion and doubts about its taxonomy is related to the existence of two ecotypes of bottlenose dolphins in many part of its distribution. The two

ecotype In evolutionary ecology, an ecotype,Greek: ''οίκος'' = home and ''τύπος'' = type, coined by Göte Turesson in 1922 sometimes called ecospecies, describes a genetically distinct geographic variety, population, or race within a specie ...

s of the common bottlenose dolphin within the western North Atlantic are represented by the shallower water or coastal ecotype and the more offshore ecotype. Their ranges overlap, but they have been shown to be genetically distinct. They are not currently described, however, as separate species or subspecies. In general, genetic variation between populations is significant, even among nearby populations. As a result of this genetic variation, other distinct species currently considered to be populations of common bottlenose dolphin are possible. Some recent genetic evidence suggests the Indo-Pacific bottlenose dolphin belongs in the genus '' Stenella'', since it is more like the Atlantic spotted dolphin (''Stenella frontalis'') than the common bottlenose dolphin. However, more recent studies indicate that this is a consequence of

reticulate evolution Reticulate evolution, or network evolution is the origination of a lineage through the partial merging of two ancestor lineages, leading to relationships better described by a phylogenetic network than a bifurcating tree. Reticulate patterns ca ...

(such as past hybridization between ''Stenella'' and ancestral ''Tursiops'') and

incomplete lineage sorting Incomplete lineage sorting, also termed hemiplasy, deep coalescence, retention of ancestral polymorphism, or trans-species polymorphism, describes a phenomenon in population genetics when ancestral gene copies fail to coalesce (looking backwards i ...

, and thus support ''T''. ''truncatus'' and ''T. aduncus'' belonging to the same genus. Baby wolphin by pinhole

Hybrids

Bottlenose dolphins have been known to hybridize with other dolphin species. Hybrids with

Risso's dolphin Risso's dolphin (''Grampus griseus'') is a dolphin, the only species of the genus ''Grampus''. Some of the closest related species to these dolphins include: pilot whales (''Globicephala'' spp.), pygmy killer whales (''Feresa attenuata''), melon ...

occur both in the wild and in captivity. The best known hybrid is the

wholphin A wholphin (portmanteau of whale + dolphin) is an extremely rare cetacean hybrid born from a mating of a female common bottlenose dolphin (''Tursiops truncatus'') with a male false killer whale (''Pseudorca crassidens''). The name implies a hy ...

, a

false killer whale The false killer whale (''Pseudorca crassidens'') is a species of oceanic dolphin that is the only extant representative of the genus '' Pseudorca''. It is found in oceans worldwide but mainly in tropical regions. It was first described in 184 ...

-bottlenose dolphin hybrid. The wholphin is fertile, and two currently live at the Sea Life Park in Hawaii. The first was born in 1985 to a female bottlenose. Wholphins also exist in the wild. In captivity, a bottlenose dolphin and a

rough-toothed dolphin The rough-toothed dolphin (''Steno bredanensis'') is a species of dolphin that can be found in deep warm and tropical waters around the world. The species was first described by Georges Cuvier in 1823. The genus name ''Steno'', of which this spe ...

hybridized. A

common dolphin The common dolphin (''Delphinus delphis'') is the most abundant cetacean in the world, with a global population of about six million. Despite this fact and its vernacular name, the common dolphin is not thought of as the archetypal dolphin, wit ...

-bottlenose dolphin hybrid born in captivity lives at

SeaWorld SeaWorld is an American theme park chain with headquarters in Orlando, Florida. It is a proprietor of marine mammal parks, oceanariums, animal theme parks, and rehabilitation centers owned by SeaWorld Parks & Entertainment (one park will be ...

California. Other hybrids live in captivity around the world and in the wild, such as a bottlenose dolphin-Atlantic spotted dolphin hybrid.

Fossil species

Bottlenose dolphins appeared during the

Miocene The Miocene ( ) is the first epoch (geology), geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and mea ...

. Known fossil species include ''Tursiops osennae'' (late Miocene to early

Pliocene The Pliocene ( ; also Pleiocene) is the epoch in the geologic time scale that extends from 5.333 million to 2.58Piacenzian coastal mudstone, and ''Tursiops miocaenus'' (Miocene) from the

Burdigalian The Burdigalian is, in the geologic timescale, an age or stage in the early Miocene. It spans the time between 20.43 ± 0.05 Ma and 15.97 ± 0.05 Ma (million years ago). Preceded by the Aquitanian, the Burdigalian was the first and longest w ...

marine sandstone, all in Italy.

Description

The bottlenose dolphin weighs an average of 300 kg (660 pounds), but can range from .American Cetacean Society Fact Sheet �
Bottlenose Dolphin
It can reach a length of just over 4 meters (13 feet). Its color varies considerably, is usually dark gray on the back and lighter gray on the flanks, but it can be bluish-grey, brownish-grey, or even nearly black, and is often darker on the back from the rostrum to behind the

dorsal fin A dorsal fin is a fin located on the back of most marine and freshwater vertebrates within various taxa of the animal kingdom. Many species of animals possessing dorsal fins are not particularly closely related to each other, though through c ...

. This is called

countershading Countershading, or Thayer's law, is a method of camouflage in which an animal's coloration is darker on the top or upper side and lighter on the underside of the body. This pattern is found in many species of mammals, reptiles, birds, fish, a ...

and is a form of

camouflage Camouflage is the use of any combination of materials, coloration, or illumination for concealment, either by making animals or objects hard to see, or by disguising them as something else. Examples include the leopard's spotted coat, the b ...

. Older dolphins sometimes have a few spots. Bottlenose dolphins can live for more than 40 years. Females typically live 5–10 years longer than males, with some females exceeding 60 years. This extreme age is rare and less than 2% of all Bottlenose dolphins will live longer than 60 years. Bottlenose dolphins can jump to a height of 6 metres (20 feet) in the air.

Anatomy

Their elongated upper and lower jaws form what is called a rostrum, or snout, which gives the animal its common name. The real, functional nose is the blowhole on top of its head; the

nasal septum The nasal septum () separates the left and right airways of the nasal cavity, dividing the two nostrils. It is depressed by the depressor septi nasi muscle. Structure The fleshy external end of the nasal septum is called the columella or co ...

is visible when the blowhole is open. Bottlenose Dolphin KSC04pd0178 head only

Bottlenose dolphins have 18 to 28 conical teeth on each side of each jaw. The flukes (lobes of the tail) and dorsal fin are formed of dense connective tissue and do not contain

bone A bone is a rigid organ that constitutes part of the skeleton in most vertebrate animals. Bones protect the various other organs of the body, produce red and white blood cells, store minerals, provide structure and support for the body, ...

or muscle. The dorsal fin usually shows phenotypic variations that help discriminate among populations. The animal propels itself by moving the flukes up and down. The pectoral flippers (at the sides of the body) are for steering; they contain bones homologous to the forelimbs of land mammals. A bottlenose dolphin discovered in Japan has two additional pectoral fins, or "hind legs", at the tail, about the size of a human's pair of hands. Scientists believe a

mutation In biology, a mutation is an alteration in the nucleic acid sequence of the genome of an organism, virus, or extrachromosomal DNA. Viral genomes contain either DNA or RNA. Mutations result from errors during DNA replication, DNA or viral repl ...

caused the ancient trait to reassert itself as a form of

atavism In biology, an atavism is a modification of a biological structure whereby an ancestral genetic trait reappears after having been lost through evolutionary change in previous generations. Atavisms can occur in several ways; one of which is whe ...

Physiology and senses

In colder waters, they have more body fat and blood, and are more suited to deeper diving. Typically, 18%–20% of their body weight is blubber. Most research in this area has been restricted to the

North Atlantic Ocean The Atlantic Ocean is the second-largest of the world's five oceans, with an area of about . It covers approximately 20% of Earth's surface and about 29% of its water surface area. It is known to separate the "Old World" of Africa, Europe an ...

. Bottlenose dolphins typically swim at , but are capable of bursts of up to . The higher speeds can only be sustained for a short time.

Senses

The dolphin's search for food is aided by a form of

sonar Sonar (sound navigation and ranging or sonic navigation and ranging) is a technique that uses sound propagation (usually underwater, as in submarine navigation) to navigate, measure distances (ranging), communicate with or detect objects on o ...

known as echolocation: it locates objects by producing sounds and listening for the echoes. A broadband burst pulse of clicking sounds is emitted in a focused beam in front of the dolphin. When the clicking sounds hit an object in the water, like a fish or rock, they bounce off and come back to the dolphin as echoes. Echolocation tells the dolphins the shape, size, speed, distance, and location of the object. To hear the returning echo, they have two small ear openings behind the eyes, but most sound waves are transmitted to the inner ear through the lower jaw. As the object of interest is approached, the echo becomes booming, and the dolphins adjust by decreasing the intensity of the emitted sounds. (This contrasts with

bat Bats are mammals of the order Chiroptera.''cheir'', "hand" and πτερόν''pteron'', "wing". With their forelimbs adapted as wings, they are the only mammals capable of true and sustained flight. Bats are more agile in flight than most ...

s and sonar, which reduce the sensitivity of the sound receptor.) The interclick interval also decreases as the animal nears the target. Evidently, the dolphin waits for each click's echo before clicking again. Echolocation details, such as signal strength, spectral qualities, and discrimination, are well understood by researchers. Bottlenose dolphins are also able to extract shape information, suggesting they are able to form an "echoic image" or sound picture of their targets. Dolphins have sharp eyesight. The eyes are located at the sides of the head and have a

tapetum lucidum The ''tapetum lucidum'' ( ; ; ) is a layer of tissue in the eye of many vertebrates and some other animals. Lying immediately behind the retina, it is a retroreflector. It reflects visible light back through the retina, increasing the light a ...

, or reflecting membrane, at the back of the retina, which aids vision in dim light. Their horseshoe-shaped, double-slit pupils enable dolphins to have good vision both in air and underwater, despite the different indices of refraction of these media. When under water, the eyeball's lens serves to focus light, whereas in the in-air environment, the typically bright light serves to contract the specialized pupil, resulting in sharpness from a smaller aperture (similar to a

pinhole camera A pinhole camera is a simple camera without a lens but with a tiny aperture (the so-called '' pinhole'')—effectively a light-proof box with a small hole in one side. Light from a scene passes through the aperture and projects an inverted image ...

). By contrast, a bottlenose's sense of smell is poor, because its blowhole, the analog to the nose, is closed when underwater and it opens only for breathing. It has no olfactory nerves or olfactory lobe in the brain. Bottlenose dolphins are able to detect salty, sweet, bitter (

quinine Quinine is a medication used to treat malaria and babesiosis. This includes the treatment of malaria due to '' Plasmodium falciparum'' that is resistant to chloroquine when artesunate is not available. While sometimes used for nocturnal le ...

sulphate The sulfate or sulphate ion is a polyatomic anion with the empirical formula . Salts, acid derivatives, and peroxides of sulfate are widely used in industry. Sulfates occur widely in everyday life. Sulfates are salts of sulfuric acid and many ar ...

), and sour (

citric acid Citric acid is an organic compound with the chemical formula HOC(CO2H)(CH2CO2H)2. It is a colorless weak organic acid. It occurs naturally in citrus fruits. In biochemistry, it is an intermediate in the citric acid cycle, which occurs in ...

) tastes, but this has not been well-studied. Anecdotally, some individuals in captivity have been noted to have preferences for food fish types, although it is not clear if taste mediates this preference. In 2022, a study at the

University of St Andrews (Aien aristeuein) , motto_lang = grc , mottoeng = Ever to ExcelorEver to be the Best , established = , type = Public research university Ancient university , endowment ...

in Scotland found that dolphins were able to identify their "friends" and family members by the taste of their urine in the water.

Communication

Bottlenose dolphins communicate through burst pulsed sounds, whistles, and body language. Examples of body language include leaping out of the water, snapping jaws, slapping the tail on the surface and butting heads. Sounds and gestures help keep track of other dolphins in the group, and alert other dolphins to danger and nearby food. Lacking

vocal cords In humans, vocal cords, also known as vocal folds or voice reeds, are folds of throat tissues that are key in creating sounds through vocalization. The size of vocal cords affects the pitch of voice. Open when breathing and vibrating for speec ...

, they produce sounds using six air sacs near their blow hole. Each animal has a uniquely identifying, frequency-modulated narrow-band signature vocalization ( signature whistle). Researchers from the Bottlenose Dolphin Research Institute
BDRI
, based in

Sardinia Sardinia ( ; it, Sardegna, label=Italian, Corsican and Tabarchino ; sc, Sardigna , sdc, Sardhigna; french: Sardaigne; sdn, Saldigna; ca, Sardenya, label=Algherese and Catalan) is the second-largest island in the Mediterranean Sea, after ...

(Italy) have now shown whistles and burst pulsed sounds are vital to the animals' social life and mirror their behaviors. The tonal whistle sounds (the most melodious ones) allow dolphins to stay in contact with each other (above all, mothers and offspring), and to coordinate hunting strategies. The burst-pulsed sounds (which are more complex and varied than the whistles) are used "to avoid physical aggression in situations of high excitement", such as when they are competing for the same piece of food, for example. The dolphins emit these strident sounds when in the presence of other individuals moving towards the same prey. The "least dominant" one soon moves away to avoid confrontation. Other communication uses about 30 distinguishable sounds, and although famously proposed by John C. Lilly in the 1950s, no "dolphin language" has been found. However,

Herman Herman may refer to: People * Herman (name), list of people with this name * Saint Herman (disambiguation) * Peter Noone (born 1947), known by the mononym Herman Places in the United States * Herman, Arkansas * Herman, Michigan * Herman, Min ...

, Richards, and Wolz demonstrated comprehension of an artificial language by two bottlenose dolphins (named

Akeakamai Akeakamai (c. 1976 – November 12, 2003) (Nickname: Ake ("ah-KAY")) was a female Atlantic bottlenose dolphin, who, along with a companion female dolphin named Phoenix, and later tankmates Elele and Hiapo, were the subjects of Louis Herman's ani ...

and Phoenix) in the period of skepticism toward

animal language Animal languages are forms of non-human animal communication that show similarities to human language. Animals communicate through a variety of signs, such as sounds or movements. Signing among animals may be considered complex enough to be a for ...

following Herbert Terrace's critique.

Intelligence

Cognition

Cognitive abilities that have been investigated include concept formation, sensory skills, and mental representations. Such research has been ongoing since the 1970s. This includes: acoustic and behavioral mimicry, comprehension of novel sequences in an

memory Memory is the faculty of the mind by which data or information is encoded, stored, and retrieved when needed. It is the retention of information over time for the purpose of influencing future action. If past events could not be remembered ...

, monitoring of self behavior, discrimination and matching, comprehension of symbols for various body parts, comprehension of pointing gestures and gaze (as made by dolphins or humans), mirror self-recognition, and numerical values.

Tool use and culture

At least some wild bottlenose dolphins use tools. In Shark Bay, off

Western Australia Western Australia (commonly abbreviated as WA) is a state of Australia occupying the western percent of the land area of Australia excluding external territories. It is bounded by the Indian Ocean to the north and west, the Southern Ocean to th ...

, dolphins place a

marine sponge Sponges, the members of the phylum Porifera (; meaning 'pore bearer'), are a basal animal clade as a sister of the diploblasts. They are multicellular organisms that have bodies full of pores and channels allowing water to circulate through ...

on their

rostrum Rostrum may refer to: * Any kind of a platform for a speaker: **dais **pulpit * Rostrum (anatomy), a beak, or anatomical structure resembling a beak, as in the mouthparts of many sucking insects * Rostrum (ship), a form of bow on naval ships * Ros ...

, presumably to protect it when searching for food on the sandy sea bottom. This has only been observed in this bay (first in 1997), and is predominantly practiced by females. A 2005 study showed mothers most likely teach the behavior to their offspring, evincing culture (behavior learned from other species members). Mud plume feeding is a feeding technique performed by a small community of bottlenose dolphins over shallow seagrass beds (less than 1 m) in the Florida Keys in the United States. The behavior involves creation of a U-shaped plume of mud in the water column and then rushing through the plume to capture fish. Along the beaches and tidal marshes of

South Carolina )'' Animis opibusque parati'' ( for, , Latin, Prepared in mind and resources, links=no) , anthem = " Carolina";" South Carolina On My Mind" , Former = Province of South Carolina , seat = Columbia , LargestCity = Charleston , LargestMetro = ...

and

Georgia Georgia most commonly refers to: * Georgia (country), a country in the Caucasus region of Eurasia * Georgia (U.S. state), a state in the Southeast United States Georgia may also refer to: Places Historical states and entities * Related to the ...

in the United States, bottlenose dolphins cooperatively herd prey fish onto steep and sandy banks in a practice known as "strand feeding". Groups of between two and six dolphins are regularly observed creating a bow wave to force the fish out of the water. The dolphins follow the fish, stranding themselves briefly, to eat their prey before twisting their bodies back and forth in order to slide back into the water. While initially documented in South Carolina and Georgia, strand feeding has also been observed in Louisiana, Texas, Baja California, Ecuador, and Australia. Some Mauritanian dolphins cooperate with human fishermen. The dolphins drive a school of fish towards the shore, where humans await with nets. In the confusion of casting nets, the dolphins catch a large number of fish as well. Intraspecies cooperative foraging has also been observed. These behaviors may also be transmitted via teaching. Controversially, Rendell and Whitehead have proposed a structure for the study of cetacean culture. Similar cases have been observed in

Laguna, Santa Catarina Laguna is a Brazilian municipality located in the southern state of Santa Catarina, 120 kilometers south of the state's capital, Florianópolis, and north east of Porto Alegre. The population is 46,122 (2020 est.) in an area of 336.4 km². El ...

Brazil Brazil ( pt, Brasil; ), officially the Federative Republic of Brazil (Portuguese: ), is the largest country in both South America and Latin America. At and with over 217 million people, Brazil is the world's fifth-largest country by area ...

since during 19th century as well.Dr. Moti Nissani (2007
Bottlenose Dolphins in Laguna Requesting a Throw Net
(video). Supporting material for Dr. Nissani's presentation at the 2007 International Ethological Conference. Video retrieved January 24, 2016. Near

Adelaide Adelaide ( ) is the capital city of South Australia, the state's largest city and the fifth-most populous city in Australia. "Adelaide" may refer to either Greater Adelaide (including the Adelaide Hills) or the Adelaide city centre. The dem ...

, in

South Australia South Australia (commonly abbreviated as SA) is a state in the southern central part of Australia. It covers some of the most arid parts of the country. With a total land area of , it is the fourth-largest of Australia's states and territories ...

, several bottlenose dolphins " tail-walk", whereby they elevate the upper part of their bodies vertically out of the water, and propel themselves along the surface with powerful tail movements. Tail-walking mostly arises via human training in dolphinaria. In the 1980s, a female from the local population was kept at a local dolphinarium for three weeks, and the scientist suggests she copied the tail-walking behavior from other dolphins. Two other wild adult female dolphins copied it from her, and the behaviour has continued through generations until 2022. A study conducted by the

University of Chicago The University of Chicago (UChicago, Chicago, U of C, or UChi) is a private university, private research university in Chicago, Illinois. Its main campus is located in Chicago's Hyde Park, Chicago, Hyde Park neighborhood. The University of Chic ...

showed that bottlenose dolphins can remember whistles of other dolphins they had lived with after 20 years of separation. Each dolphin has a unique

whistle A whistle is an instrument which produces sound from a stream of gas, most commonly air. It may be mouth-operated, or powered by air pressure, steam, or other means. Whistles vary in size from a small slide whistle or nose flute type to a lar ...

that functions like a name, allowing the marine mammals to keep close social bonds. The new research shows that dolphins have the longest memory yet known in any species other than

humans Humans (''Homo sapiens'') are the most abundant and widespread species of primate, characterized by bipedalism and exceptional cognitive skills due to a large and complex brain. This has enabled the development of advanced tools, culture, ...

. The bottlenose dolphins of John's Pass in Boca Ciega Bay, St. Petersburg, Florida, exhibit a rare form of self-decoration and social object use called grass-wearing. Self-decoration by wearing grass appears to be an attention-getting device rather than purely play and varies from a single blade to large clusters of grass. John's Pass dolphins self-decorate with grass primarily when they form new social groups or engage in procreative activities. Grass-wearing behavior among these dolphins is a local behavioral tradition that could constitute a cultural difference from other communities.

Cortical neurons

Some researchers hypothesize that the number of nerve cells (

neuron A neuron, neurone, or nerve cell is an electrically excitable cell that communicates with other cells via specialized connections called synapses. The neuron is the main component of nervous tissue in all animals except sponges and placozoa. ...

s) in the cortex of the brain predicts intelligence in mammals. A 2019 study estimated the number of neurons in the cerebral cortex of three common bottlenose dolphins and found numbers ranging from 11.7 to 15.2 billion neurons. The human average being approximately 16 billion, this is likely within the range found in the human population.

Life history

Bottlenose dolphins have a lifespan of 40-60 years. Females can outlive males and live for 60 years or more. Dolphins start to reproduce aged 5 to 15 years.

Respiration and sleep

The bottlenose dolphin has a single blowhole located on the dorsal surface of the head consisting of a hole and a muscular flap. The flap is closed during muscle relaxation and opens during contraction. Dolphins are voluntary breathers, who must deliberately surface and open their blowholes to get air. They can store almost twice as much oxygen in proportion to their body weight as a human can: the dolphin can store 36 milliliters (ml) of oxygen per kg of body weight, compared with 20 ml per kg for humans. This is an adaptation to diving. The bottlenose dolphin typically rises to the surface to breathe through its blowhole two to three times per minute, although it can remain submerged for up to 20 minutes. Dolphins can breathe while "half-asleep". During the sleeping cycle, one brain hemisphere remains active, while the other hemisphere shuts down. The active hemisphere handles surfacing and breathing behavior. The daily sleeping cycle lasts for about 8 hours, in increments of minutes to hours. During the sleeping cycle, they remain near the surface, swimming slowly or "logging", and occasionally closing one eye.

Reproduction

Both sexes have

genital slit A dolphin is an aquatic mammal within the infraorder Cetacea. Dolphin species belong to the families Delphinidae (the oceanic dolphins), Platanistidae (the Indian river dolphins), Iniidae (the New World river dolphins), Pontoporiidae (the ...

s on the underside of their bodies. The male can retract and conceal his penis through his slit. The female's slit houses her

vagina In mammals, the vagina is the elastic, muscular part of the female genital tract. In humans, it extends from the vestibule to the cervix. The outer vaginal opening is normally partly covered by a thin layer of mucosal tissue called the hymen ...

and anus. Females have two mammary slits, each housing one

nipple The nipple is a raised region of tissue on the surface of the breast from which, in females, milk leaves the breast through the lactiferous ducts to feed an infant. The milk can flow through the nipple passively or it can be ejected by smooth m ...

, one on each side of the genital slit. The ability to stow their reproductive organs (especially in males) allows for maximum hydrodynamics. The breeding season produces significant physiological changes in males. At that time, the testes enlarge, enabling them to hold more sperm. Large amounts of sperm allow a male to wash away the previous suitor's sperm, while leaving some of his own for fertilization. Also, sperm concentration markedly increases. Having less sperm for out-of-season social mating means it wastes less. This suggests sperm production is energetically expensive. Males have large testes in relation to their body size. During the breeding season, males compete for access to females. Such competition can take the form of fighting other males or of herding females to prevent access by other males. In Shark Bay, male bottlenose dolphins have been observed working in pairs or larger groups to follow and/or restrict the movement of a female for weeks at a time, waiting for her to become

sexually receptive Animal sexual behaviour takes many different forms, including within the same species. Common mating or reproductively motivated systems include monogamy, polygyny, polyandry, polygamy and promiscuity. Other sexual behaviour may be reprodu ...

. These coalitions, also known as male reproductive alliances, will fight with other coalitions for control of females.Connor R. C. (1990) ''Alliances among male bottlenose dolphins and comparative analyses of mutualism''. Ph.D. Dissertation. The University of Michigan, Michigan. Humans and dolphins are the only species that share this type of "gang formation" habit as a form of cooperation. Mating occurs belly to belly. Dolphins have been observed engaging in intercourse when the females are not in their estrous cycles and cannot produce young, suggesting they may mate for pleasure. The gestation period averages 12 months. Births can occur at any time of year, although peaks occur in warmer months. The young are born in shallow water, sometimes assisted by a (possibly male) "midwife", and usually only a single calf is born. Twins are possible, but rare. Newborn bottlenose dolphins are long and weigh , with Indo-Pacific bottlenose dolphin infants being generally smaller than common bottlenose dolphin infants. To accelerate nursing, the mother can eject milk from her

mammary gland A mammary gland is an exocrine gland in humans and other mammals that produces milk to feed young offspring. Mammals get their name from the Latin word ''mamma'', "breast". The mammary glands are arranged in organs such as the breasts in pri ...

s. The calf suckles for 18 months to up to 8 years, and continues to closely associate with its mother for several years after weaning. Females sexually mature at ages 5–13, males at ages 9–14. Females reproduce every two to six years. Reproduction is moderately seasonal (September-January), peaking from October to December. Calf loss between August and December is followed by rapid conception (1-2 months), whereas conception is delayed (2-9 months) if calf loss occurs between January and July. Weaning ages ranged from 2.7 to 8.0 years, but 66.7% (42 calves) were weaned by their fourth birthday. Females tended to wean mid-pregnancy. Group size was unrelated to water depth or female reproductive success, but reproductive success was predicted by water depth. Shallow water may allow mothers and calves to detect and avoid predatory sharks. Alternatively, or additionally, prey density may be higher in shallow water compared to deep water.

Georgetown University Georgetown University is a private university, private research university in the Georgetown (Washington, D.C.), Georgetown neighborhood of Washington, D.C. Founded by Bishop John Carroll (archbishop of Baltimore), John Carroll in 1789 as Georg ...

professor Janet Mann argues the strong personal behavior among male calves is about bond formation and benefits the species in an evolutionary context. She cites studies showing these dolphins as adults are inseparable, and that early bonds aid protection, as well as in locating females. Female bottlenose dolphins have to expend additional energy in carrying out parental care, ''e.g.'', infant-carrying behavior. Dolphins don't physically hold their infants but line up in an echelon position with infants swimming beside them. This position creates a change of water flow pattern from the infant which minimizes separation between the mother and infant, but also increases the mother's surface area and creates a drag for the swimmer. This also leaves less energy to use in swimming speed, foraging, and predator evasion.

Social interaction

Adult males live mostly alone or in groups of two to three, and join pods for short periods of time. Adult females and young dolphins normally live in groups of up to 15 animals. Males give strong mutual support if other males help them, even if they are not friends. However, they live in fission-fusion societies of varying group size, within which individuals change associations, often on a daily or hourly basis. Group compositions are usually determined by sex, age, reproductive condition, familial relations and affiliation histories. In a dolphin community near

Sarasota, Florida Sarasota () is a city in Sarasota County on the Gulf Coast of the U.S. state of Florida. The area is renowned for its cultural and environmental amenities, beaches, resorts, and the Sarasota School of Architecture. The city is located in the sou ...

, the most common group types are adult females with their recent offspring, older subadults of both sexes, and adult males either alone or in bonded pairs. Smaller groups can join to form larger groups of 100 or more, and occasionally exceed 1,000. The social strategies of marine mammals such as bottlenose dolphins "provide interesting parallels" with the social strategies of elephants and chimpanzees. Bottlenose dolphins studied by Bottlenose Dolphin Research Institute researchers off the island of Sardinia show random social behavior while feeding, and their social behavior does not depend on feeding activity. In Sardinia, the presence of a floating marine fin-fish farm has been linked to a change in bottlenose dolphin distribution as a result of high fish density around the floating cages in the farming area.

Ecology

Feeding

Fish is one of the main items in the dolphin diet. They also eat shrimps, squid, mollusks, and cuttlefish, and only swallow the soft parts. They eat 22 pounds of fish a day. When they encounter a shoal of fish, they work as a team to herd them towards the shore to maximize the harvest. They also hunt alone, often targeting bottom-dwelling species. The bottlenose dolphin sometimes hits a fish with its fluke, sometimes knocking it out of the water, using a strategy called "fish whacking". "Strand feeding" is an inherited feeding technique used by bottlenose dolphins near and around coastal regions of Georgia and South Carolina. When a pod finds a school of fish, they will circle the school and trap the fish in a mini whirlpool. Then, the dolphins will charge at the school and push their bodies up onto a mud-flat, forcing the fish on the mud-flat, as well. The dolphins then crawl around on their sides, consuming the fish they washed up on shore. This happens only during low tides. One type of feeding behavior seen in bottlenose dolphins is mud ring feeding. Bottlenose dolphins conflict with small-scale coastal commercial fisheries in some Mediterranean areas. Common bottlenose dolphins are probably attracted to fishing nets because they offer a concentrated food source.

Relations with other species

Dolphins can exhibit altruistic behaviour toward other sea creatures. On Mahia Beach, New Zealand, on March 10, 2008, two

pygmy sperm whale The pygmy sperm whale (''Kogia breviceps'') is one of two extant species in the family Kogiidae in the sperm whale superfamily. They are not often sighted at sea, and most of what is known about them comes from the examination of stranded speci ...

s, a female and calf, stranded on the beach. Rescuers attempted to refloat them four times. Shortly, a playful bottlenose dolphin known to local residents as

Moko In the mythology of Mangaia in the Cook Islands, Moko is a wily character and grandfather of the heroic Ngaru. Moko is a ruler or king of the lizard Lizards are a widespread group of squamate reptiles, with over 7,000 species, ranging acro ...

arrived and, after apparently vocalizing at the whales, led them along a sandbar to the open sea, saving them from imminent euthanasia. In 2019 a female was observed caring for a juvenile

melon-headed whale The melon-headed whale (''Peponocephala electra''), also known less commonly as the electra dolphin, little killer whale, or many-toothed blackfish, is a toothed whale of the oceanic dolphin family (Delphinidae). The common name is derived fro ...

, the first reported instance of a bottlenose dolphin adopting a non-conspecific infant. The bottlenose dolphin can behave aggressively. Males fight for rank and access to females. During mating season, males compete vigorously with each other through displays of toughness and size, with a series of acts, such as head-butting. They display aggression towards

shark Sharks are a group of elasmobranch fish characterized by a cartilaginous skeleton, five to seven gill slits on the sides of the head, and pectoral fins that are not fused to the head. Modern sharks are classified within the clade Selachi ...

s and smaller dolphin species. At least one population, off

Scotland Scotland (, ) is a Countries of the United Kingdom, country that is part of the United Kingdom. Covering the northern third of the island of Great Britain, mainland Scotland has a Anglo-Scottish border, border with England to the southeast ...

, has practiced infanticide, and also has attacked and killed

harbour porpoise The harbour porpoise (''Phocoena phocoena'') is one of eight extant species of porpoise. It is one of the smallest species of cetacean. As its name implies, it stays close to coastal areas or river estuaries, and as such, is the most familiar ...

University of Aberdeen , mottoeng = The fear of the Lord is the beginning of wisdom , established = , type = Public research universityAncient university , endowment = £58.4 million (2021) , budget ...

researchers say the dolphins do not eat their victims, but are simply competing for food. However, Dr. Read of Duke University, a porpoise expert researching similar cases of porpoise killings that had occurred in

Virginia Virginia, officially the Commonwealth of Virginia, is a state in the Mid-Atlantic and Southeastern regions of the United States, between the Atlantic Coast and the Appalachian Mountains. The geography and climate of the Commonwealth ar ...

in 1996 and 1997, holds a different view. He states dolphins and porpoises feed on different types of fish, thus food competition is an unlikely cause of the killings. Similar behaviour has been observed in Ireland. In the first half of July 2014, four attacks with three porpoise fatalities were observed and caught on video by the Cardigan Bay Marine Wildlife Centre in the

Cardigan Bay Cardigan Bay ( cy, Bae Ceredigion) is a large inlet of the Irish Sea, indenting the west coast of Wales between Bardsey Island, Gwynedd in the north, and Strumble Head, Pembrokeshire at its southern end. It is the largest bay in Wales. Geo ...

Wales Wales ( cy, Cymru ) is a country that is part of the United Kingdom. It is bordered by England to the east, the Irish Sea to the north and west, the Celtic Sea to the south west and the Bristol Channel to the south. It had a population in ...

.''Dolphin attacks on porpoises baffle experts''
BBC News, July 15, 2014 The bottlenose dolphin sometimes forms mixed species groups with other species from the dolphin family, particularly larger species, such as the

short-finned pilot whale The short-finned pilot whale (''Globicephala macrorhynchus'') is one of the two species of cetaceans in the genus '' Globicephala'', which it shares with the long-finned pilot whale (''G. melas''). It is part of the oceanic dolphin family (Del ...

, the false killer whale and Risso's dolphin. They also interact with smaller species, such as the Atlantic spotted dolphin and the rough-toothed dolphin. While interactions with smaller species are sometimes affiliative, they can also be hostile.

Predators

Some large shark species, such as the

tiger shark The tiger shark (''Galeocerdo cuvier'') is a species of requiem shark and the last extant member of the family Galeocerdonidae. It is a large macropredator, capable of attaining a length over . Populations are found in many tropical and tempera ...

, the dusky shark, the

great white shark The great white shark (''Carcharodon carcharias''), also known as the white shark, white pointer, or simply great white, is a species of large Lamniformes, mackerel shark which can be found in the coastal surface waters of all the major ocean ...

and the

bull shark The bull shark (''Carcharhinus leucas''), also known as the Zambezi shark (informally zambi) in Africa and Lake Nicaragua shark in Nicaragua, is a species of requiem shark commonly found worldwide in warm, shallow waters along coasts and in ri ...

, prey on the bottlenose dolphin, especially calves. The bottlenose dolphin is capable of defending itself by charging the predator; dolphin 'mobbing' behavior of sharks can occasionally prove fatal for the shark. Targeting a single adult dolphin can be dangerous for a shark of similar size.

Killer whale The orca or killer whale (''Orcinus orca'') is a toothed whale belonging to the oceanic dolphin family, of which it is the largest member. It is the only extant species in the genus ''Orcinus'' and is recognizable by its black-and-white ...

populations in New Zealand and Peru have been observed preying on bottlenose dolphins, but this seems rare, and other orcas may swim with dolphins. Swimming in pods allows dolphins to better defend themselves against predators. Bottlenose dolphins either use complex evasive strategies to outswim their predators, or mobbing techniques to batter the predator to death or force it to flee.

Relation to humans

Interaction

Bottlenose Dolphin -Notojima Aquarium -Ishikawa -Japan-8a

The species sometimes shows curiosity towards humans in or near water. Occasionally, they rescue injured divers by raising them to the surface. They also do this to help injured members of their own species. In November 2004, a dramatic report of dolphin intervention came from

New Zealand New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and over 700 smaller islands. It is the sixth-largest island count ...

. Four lifeguards, swimming off the coast near Whangarei, were approached by a shark (reportedly a great white shark). Bottlenose dolphins herded the swimmers together and surrounded them for 40 minutes, preventing the shark from attacking, as they slowly swam to shore. In coastal regions, dolphins run the risk of colliding with boats. Researchers of the Bottlenose Dolphin Research Institute first quantified data about solitary bottlenose dolphin diving behavior in the presence and absence of boats. Dolphins responded more to tourist than fishing vessels. Driving behavior, speed, engine type and separation distance all affected dolphin safety. However, dolphins in these areas can also coexist with humans. For example, in the town of Laguna in south Brazil, a pod of bottlenose dolphins resides in the estuary, and some of its members cooperate with humans. These cooperating dolphins are individually recognized by the local fishermen, who name them. The fishermen typically stand up to their knees in the shallow waters or sit in canoes, waiting for the dolphins. Now and then, one or more dolphins appear, driving the fish towards the line of fishermen. One dolphin then displays a unique body movement outside the water, which serves as a signal to the fishermen to cast their nets (the entire sequence is shown here, and a detailed description of the signal's characteristics is available here). In this unique form of cooperation, the dolphins gain because the fish are disoriented and because the fish cannot escape to shallow water where the larger dolphins cannot swim. Likewise, studies show that fishermen casting their nets following the unique signal catch more fish than when fishing alone, without the help of the dolphins. The dolphins were not trained for this behavior; the collaboration began before 1847. Similar cooperative fisheries also exist in Mauritania, Africa. Commercial 'dolphin encounter' enterprises and tours operate in many countries. The documentary film '' The Cove'' documents how dolphins are captured and sold to some of these enterprises (particularly in Asia) while the remaining pod is slaughtered. In addition to such endeavors, the individuals swim with and surface near surfers at the beach. Bottlenose dolphins perform in many aquaria, generating controversy. Animal welfare activists and certain scientists have claimed that the dolphins do not have adequate space or receive adequate care or stimulation. However, others, notably SeaWorld, counter by claiming that the dolphins are properly cared for, have much environmental stimulation and enjoy interacting with humans. Eight bottlenose dolphins that lived at the Marine Life Aquarium in

Gulfport, Mississippi Gulfport is the second-largest city in Mississippi after the state capital, Jackson. Along with Biloxi, Gulfport is the co-county seat of Harrison County and the larger of the two principal cities of the Gulfport-Biloxi, Mississippi Metropolit ...

were swept away from their aquarium pool during Hurricane Katrina. They were later found in the

Gulf of Mexico The Gulf of Mexico ( es, Golfo de México) is an ocean basin and a marginal sea of the Atlantic Ocean, largely surrounded by the North American continent. It is bounded on the northeast, north and northwest by the Gulf Coast of the United ...

and returned to captivity. NMMP dolphin with locator

The

military of the United States The United States Armed Forces are the military forces of the United States. The armed forces consists of six service branches: the Army, Marine Corps, Navy, Air Force, Space Force, and Coast Guard. The president of the United States is th ...

and

Russia Russia (, , ), or the Russian Federation, is a transcontinental country spanning Eastern Europe and Northern Asia. It is the largest country in the world, with its internationally recognised territory covering , and encompassing one-eig ...

train bottlenose dolphins as military dolphins for wartime tasks, such as locating sea mines and detecting enemy divers. The U.S.'s program is the U.S. Navy Marine Mammal Program, located in San Diego. Tião was a well-known solitary male bottlenose dolphin that was first spotted in the town of São Sebastião in Brazil around 1994 and frequently allowed humans to interact with him. The dolphin became infamous for killing a swimmer and injuring many others, which later earned him the nickname "Killer Dolphin".

Cultural influence

The popular television show '' Flipper'', created by

Ivan Tors Ivan Tors (born Iván Törzs; June 12, 1916 – June 4, 1983) was a Hungarian playwright, film director, screenwriter, and film and television producer with an emphasis on non-violent but exciting science fiction, underwater sequences, and stori ...

, portrayed a bottlenose dolphin in a friendly relationship with two boys, Sandy and Bud. A seagoing " Lassie", Flipper understood English and was a hero: "Go tell Dad we're in trouble, Flipper! Hurry!" The show's theme song contains the lyric "no one you see / is smarter than he". The television show was based on a 1963 film, with a sequel,

Flipper's New Adventure ''Flipper's New Adventure'' (known in some countries as ''Flipper and the Pirates'') is a 1964 American feature film released on June 24, 1964 by Metro-Goldwyn-Mayer, written by Art Arthur, and directed by Leon Benson. It was a sequel to the 1963 ...

(1964), and was remade as a feature film in 1996, starring

Elijah Wood Elijah Jordan Wood (born January 28, 1981) is an American actor and producer. He is best known for his portrayal of Frodo Baggins in the ''Lord of the Rings'' film trilogy (2001–2003) and '' The Hobbit: An Unexpected Journey'' (2012). Woo ...

and

Paul Hogan Paul Hogan (born 8 October 1939) is an Australian actor and comedian. He was nominated for the Academy Award for Best Original Screenplay and won the Golden Globe Award for Best Actor – Motion Picture Musical or Comedy for his performance as ...

, as well as a second TV series running from 1995 to 2000, starring

Jessica Alba Jessica Marie Alba ( ; born April 28, 1981) is an American actress and businesswoman. She began her television and movie appearances at age 13 in '' Camp Nowhere'' and '' The Secret World of Alex Mack'' (1994), and rose to prominence at age 19 ...

. Other television appearances by bottlenose dolphins include ''

Wonder Woman Wonder Woman is a superhero created by the American psychologist and writer William Moulton Marston (pen name: Charles Moulton), and artist Harry G. Peter. Marston's wife, Elizabeth Holloway Marston, Elizabeth, and their life partner, Olive Byr ...

'', ''

Highway to Heaven ''Highway to Heaven'' is an American fantasy drama television series that ran on NBC from September 19, 1984, to August 4, 1989. The series starred Michael Landon as Jonathan Smith, an angel sent to Earth in order to help people in need. Victo ...

'', '' Dolphin Cove'', '' seaQuest DSV'', and

The Penguins of Madagascar ''The Penguins of Madagascar'' is an American computer-animated television series co-produced by DreamWorks Animation and Nickelodeon. It stars nine characters from DreamWorks' animated film ''Madagascar'': the penguins Skipper ( Tom McGrath), ...

, in which a dolphin, Doctor Blowhole, is a villain. In the HBO movie '' Zeus and Roxanne'', a female bottlenose dolphin befriends a male dog, and in ''Secrets of the Bermuda Triangle'' (1996 Ian Toynton movie), a girl named Annie (played by

Lisa Jakub Lisa Jakub () (born December 27, 1978) is a Canadian writer, yoga teacher, and former actress. She is best known for her roles as Lydia Hillard in the comedy-drama film ''Mrs. Doubtfire'' (1993) and as Alicia Casse in '' Independence Day'' (1996). ...

) swims with dolphins. Human and dolphin interaction segments, shot on location in the Florida Keys with

Dolphin Research Center The Dolphin Research Center (DRC) is a dolphinarium on Grassy Key, Florida. The series of saltwater lagoons is home to several dolphins and California sea lions. History Fisherman Milton Santini opened Santini's Porpoise School in 1958, which he ...

, are featured on ''

Sesame Street ''Sesame Street'' is an American educational children's television series that combines live-action, sketch comedy, animation and puppetry. It is produced by Sesame Workshop (known as the Children's Television Workshop until June 2000) ...

'' and on a Halloween episode of ''

The Simpsons ''The Simpsons'' is an American animated sitcom created by Matt Groening for the Fox Broadcasting Company. The series is a satirical depiction of American life, epitomized by the Simpson family, which consists of Homer Simpson, Homer, Marge ...

'',

Treehouse of Horror XI "Treehouse of Horror XI" is the first episode of the twelfth season of the American animated television series ''The Simpsons'', the 249th episode overall, and the eleventh Halloween episode. The episode features "G-G-Ghost D-D-Dad", "Scary Tales ...

. ''

Dolphin Tale ''Dolphin Tale'' is a 2011 American 3D family drama film directed by Charles Martin Smith, from a screenplay by Karen Janszen and Noam Dromi and a book of the same name. It stars Harry Connick Jr., Ashley Judd, Nathan Gamble, Kris Kristofferson, ...

'', directed by

Charles Martin Smith Charles Martin Smith (born October 30, 1953) is an American actor, writer, and director of film and television, based in British Columbia. He is known for his roles in ''American Graffiti'' (1973), ''The Buddy Holly Story'' (1978), '' Never Cry Wo ...

, starring Nathan Gamble,

Ashley Judd Ashley Judd (born Ashley Tyler Ciminella; April 19, 1968) is an American actress. She grew up in a family of performing artists: she is the daughter of the late country music singer Naomi Judd and the half-sister of country music singer Wynonna ...

, Harry Connick Jr., Morgan Freeman, Cozi Zuehlsdorff and

Kris Kristofferson Kristoffer Kristofferson (born June 22, 1936) is a retired American singer, songwriter and actor. Among his songwriting credits are " Me and Bobby McGee", " For the Good Times", " Sunday Mornin' Comin' Down", and " Help Me Make It Through the ...

, is based on the real-life story of the dolphin

Winter Winter is the coldest season of the year in polar and temperate climates. It occurs after autumn and before spring. The tilt of Earth's axis causes seasons; winter occurs when a hemisphere is oriented away from the Sun. Different cultur ...

, who was rescued from a crab trap in December 2005 and lost her tail, but learned to swim with a prosthetic one. ''

Dolphin Tale 2 ''Dolphin Tale 2'' is a 2014 American family film written and directed by Charles Martin Smith as the sequel to his 2011 film ''Dolphin Tale'' which in-turn was based on the true story about a rescued bottlenose dolphin named Winter who made her f ...

'', a sequel to the 2011 film, featured another rescued dolphin named Hope and an appearance by Bethany Hamilton. The sequel was released on September 12, 2014. The NFL's

Miami Dolphins The Miami Dolphins are a professional American football team based in the Miami metropolitan area. They compete in the National Football League (NFL) as a member team of the league's American Football Conference (AFC) East division. The team p ...

uses the bottlenose dolphin as its mascot and team logo. Factual descriptions of the dolphins date back into antiquity — the writings of

Aristotle Aristotle (; grc-gre, Ἀριστοτέλης ''Aristotélēs'', ; 384–322 BC) was a Greek philosopher and polymath during the Classical period in Ancient Greece. Taught by Plato, he was the founder of the Peripatetic school of ph ...

, Oppian and

Pliny the Elder Gaius Plinius Secundus (AD 23/2479), called Pliny the Elder (), was a Roman author, naturalist and natural philosopher, and naval and army commander of the early Roman Empire, and a friend of the emperor Vespasian. He wrote the encyclopedic ' ...

all mention the species.

Threats

Millions of dolphins drown in fishing nets. Tuna fishing crews have been the most responsible for the largest number of deaths. In 1972, the U.S government passed a law limiting the number of dolphins that could be killed yearly by tuna fishing crews. Dolphins in the United Kingdom have also been found to contain high levels of pollutants in their tissues. Heavy metals including mercury, PCB's and DDT are of great concern. These pollutants can cause harm in dolphins growth development, reproduction, and immunity. Since the mid-1990s, hundreds of dolphins have been trained to perform in shows presented by aquariums, zoos, and amusement parks. Scientists conduct various types of research to understand the dolphin's communication system. The man-made chemical

perfluorooctanesulfonic acid Perfluorooctanesulfonic acid (PFOS) (conjugate base perfluorooctanesulfonate) is a chemical compound having an eight-carbon fluorocarbon chain and a sulfonic acid functional group and thus a perfluorosulfonic acid. It is an anthropogenic (man-ma ...

(PFOS) may be compromising the

immune system The immune system is a network of biological processes that protects an organism from diseases. It detects and responds to a wide variety of pathogens, from viruses to parasitic worms, as well as cancer cells and objects such as wood splint ...

of bottlenose dolphins. PFOS affects the immune system of male mice at a concentration of 91.5 ppb, while PFOS has been reported in bottlenose dolphins in excess of 1 ppm. High levels of metal contaminants have been measured in tissues in many areas of the globe. A recent study found high levels of

cadmium Cadmium is a chemical element with the symbol Cd and atomic number 48. This soft, silvery-white metal is chemically similar to the two other stable metals in group 12, zinc and mercury. Like zinc, it demonstrates oxidation state +2 in most of ...

and mercury in bottlenose dolphins from South Australia, levels which were later found to be associated with kidney malformations, indicating possible health effects of high heavy metal concentrations in dolphins.

Conservation

Bottlenose dolphins are not endangered. Their future is stable because of their abundance and adaptability. However, specific populations are threatened due to various environmental changes. The population in the Moray Firth in Scotland is estimated to consist of around 190 individuals, and are under threat from harassment, traumatic injury, water pollution and reduction in food availability. Likewise, an isolated population in Doubtful Sound, New Zealand, is in decline due to calf loss coincident to an increase in warm freshwater discharge into the fiord. Less local

climate change In common usage, climate change describes global warming—the ongoing increase in global average temperature—and its effects on Earth's climate system. Climate change in a broader sense also includes previous long-term changes to ...

, such as increasing water temperature may also play a role but has never been shown to be the case. One of the largest coastal populations of bottlenose dolphins in Shark Bay, Western Australia was forecast to be stable with little variation in mortality over time (Manlik ''et al.'' 2016). In United States waters, hunting and harassing of marine mammals is forbidden in almost all circumstances, from passage of the Marine Mammal Protection Act of 1972.

References

External links

Voices in the Sea Sounds and Videos of the Bottlenose Dolphin

{{Authority control Oceanic dolphins Cosmopolitan mammals Symbols of Mississippi Tool-using mammals Animals that use echolocation Taxa named by Paul Gervais