Dolphins

@article{doi101038207434a0,
    author = "Caldwell, Melba C. and Caldwell, David K.‏",
    title = "Individualized Whistle Contours in Bottle-nosed Dolphins (Tursiops truncatus)",
    year = "1965",
    journal = "Nature",
    url = "https://doi.org/10.1038/207434a0",
    doi = "10.1038/207434a0",
    openalex = "W1991640646"
}

The echlocation signals of two Atlantic bottlenose dolphins, Tursiops truncatus, were measured while the animals were involved in a target-detection experiment conducted in open waters. The time intervals between successive pulses in a pulse train were found to be highly variable, although the intervals were longer than the time needed for an acoustic signal to travel from the animals to the target and back. Sound pressure levels of the echoranging signals were measured for target ranges of 60, 70, 75, and 80 yds. The peak-to-peak click-source level at 1 yd showed little variation with the target range; the average level was 120.4 dB re 1 μbar for one animal and 122.3 dB for the other. These open-water sound pressure levels are at least 30 dB higher than any click-source levels reported in the literature. Oscilloscope photographs and their Fourier transforms of these high-amplitude clicks are presented. The typical clicks had average durations of 40 μsec, with peak energies between 120 and 130 kHz, much higher than the previously reported energy peaks centered at 35 to 60 kHz.

@article{doi10112111903419,
    author = "Au, Whitlow W. L. and Floyd, Robert W. and Penner, Ralph H. and Murchison, A. Earl",
    title = "Measurement of echolocation signals of the Atlantic bottlenose dolphin, Tursiops truncatus Montagu, in open waters",
    year = "1974",
    journal = "The Journal of the Acoustical Society of America",
    abstract = "The echlocation signals of two Atlantic bottlenose dolphins, Tursiops truncatus, were measured while the animals were involved in a target-detection experiment conducted in open waters. The time intervals between successive pulses in a pulse train were found to be highly variable, although the intervals were longer than the time needed for an acoustic signal to travel from the animals to the target and back. Sound pressure levels of the echoranging signals were measured for target ranges of 60, 70, 75, and 80 yds. The peak-to-peak click-source level at 1 yd showed little variation with the target range; the average level was 120.4 dB re 1 μbar for one animal and 122.3 dB for the other. These open-water sound pressure levels are at least 30 dB higher than any click-source levels reported in the literature. Oscilloscope photographs and their Fourier transforms of these high-amplitude clicks are presented. The typical clicks had average durations of 40 μsec, with peak energies between 120 and 130 kHz, much higher than the previously reported energy peaks centered at 35 to 60 kHz.",
    url = "https://doi.org/10.1121/1.1903419",
    doi = "10.1121/1.1903419",
    openalex = "W2001693471"
}

@misc{wursig1979dolphins1,
    author = "Wursig, B",
    title = "Dolphins",
    year = "1979",
    howpublished = "Scientific American, v. 240, no. 3, p. 136-148",
    note = "talkorigins\_source = {true}; raw\_reference = {Wursig, B., 1979, Dolphins: Scientific American, v. 240, no. 3, p. 136-148.}"
}

A bstract The authors review the literature on bottlenose dolphin ecology, behavior and social organization, focusing on data collected on free‐ranging animals. Most bottlenose dolphins studied to date have had definable home ranges, and behavioral, morphological and biochemical information indicates discrete stocks in some areas. Bottlenose dolphins appear to form relatively permanent social groups based on sex and age. Mother—calf bonds are long‐lasting. Movement patterns are extremely variable from location to location but are relatively predictable at any given site. Food resources are one of the most important factors affecting movements. Bottlenose dolphin behavior is very flexible, and these dolphins are generally active day and night. Feeding peaks in the morning and afternoon have been observed at several sites. Social behavior is an important component of daily activities. Sharks are the most significant predator on bottlenose dolphins in most areas, but captive and wild studies show that dolphins and sharks frequently live in harmony as well. Human activities may be helpful, harmful or neutral to bottlenose dolphins, but interactions with humans are frequent for these coastal cetaceans.

@article{doi101111j174876921986tb00026x,
    author = "Shane, Susan H. and Wells, Randall S. and Würsig, Bernd",
    title = "ECOLOGY, BEHAVIOR AND SOCIAL ORGANIZATION OF THE BOTTLENOSE DOLPHIN: A REVIEW",
    year = "1986",
    journal = "Marine Mammal Science",
    abstract = "A bstract The authors review the literature on bottlenose dolphin ecology, behavior and social organization, focusing on data collected on free‐ranging animals. Most bottlenose dolphins studied to date have had definable home ranges, and behavioral, morphological and biochemical information indicates discrete stocks in some areas. Bottlenose dolphins appear to form relatively permanent social groups based on sex and age. Mother—calf bonds are long‐lasting. Movement patterns are extremely variable from location to location but are relatively predictable at any given site. Food resources are one of the most important factors affecting movements. Bottlenose dolphin behavior is very flexible, and these dolphins are generally active day and night. Feeding peaks in the morning and afternoon have been observed at several sites. Social behavior is an important component of daily activities. Sharks are the most significant predator on bottlenose dolphins in most areas, but captive and wild studies show that dolphins and sharks frequently live in harmony as well. Human activities may be helpful, harmful or neutral to bottlenose dolphins, but interactions with humans are frequent for these coastal cetaceans.",
    url = "https://doi.org/10.1111/j.1748-7692.1986.tb00026.x",
    doi = "10.1111/j.1748-7692.1986.tb00026.x",
    openalex = "W1984455459"
}

@incollection{doi10100797814757990957,
    author = "Wells, Randall S. and Scott, Michael and Irvine, A. Blair",
    title = "The Social Structure of Free-Ranging Bottlenose Dolphins",
    year = "1987",
    url = "https://doi.org/10.1007/978-1-4757-9909-5\_7",
    doi = "10.1007/978-1-4757-9909-5\_7",
    openalex = "W108350391",
    references = "doi1010160022519371901895, doi101016b9780126525700x50015, doi101126science327542, doi101163156853974x00345, doi101163156853980x00447, doi1023072063069, doi1023072285423, doi1023072576242, doi1023072830, doi10432497813151292667, openalexw1484524608"
}

@incollection{doi101016b9780124402805500160,
    author = "Shane, Susan H.",
    title = "Behavior and Ecology of the Bottlenose Dolphin at Sanibel Island, Florida",
    year = "1990",
    booktitle = "Elsevier eBooks",
    url = "https://doi.org/10.1016/b978-0-12-440280-5.50016-0",
    doi = "10.1016/b978-0-12-440280-5.50016-0",
    openalex = "W2483524160",
    references = "doi10100797814757990957"
}

Abstract Patterns of association among bottlenose dolphins resident in Shark Bay, Western Australia were analyzed using party membership data. Parties contained an average of 4.8 individuals, but party size and composition were unstable. While these temporary parties often contained both males and females, long term consistent associations generally were between members of the same sex. The highest association coefficients, resulting from very frequent co-occurrence within parties were between males and between mothers and offspring. Males formed subgroups of two or three individuals who consistently associated with each other, and these were stable over periods of at least seven years in some cases. Male subgroups preferentially associated with particular other male subgroups. Females associated most consistently with other females, although not to the same extent as some males. Female associations were better described as a network rather than discrete subgroups. Male-female associations were generally inconsistent and depended in part on female reproductive state. Mothers and their offspring associated very consistently for at least 4 years.

@article{doi101163156853992x00101,
    author = "Smolker, Rachel A. and Richards, Andrew F. and Connor, Richard C. and Pepper, John W.",
    title = "Sex Differences in Patterns of Association Among Indian Ocean Bottlenose Dolphins",
    year = "1992",
    journal = "Behaviour",
    abstract = "Abstract Patterns of association among bottlenose dolphins resident in Shark Bay, Western Australia were analyzed using party membership data. Parties contained an average of 4.8 individuals, but party size and composition were unstable. While these temporary parties often contained both males and females, long term consistent associations generally were between members of the same sex. The highest association coefficients, resulting from very frequent co-occurrence within parties were between males and between mothers and offspring. Males formed subgroups of two or three individuals who consistently associated with each other, and these were stable over periods of at least seven years in some cases. Male subgroups preferentially associated with particular other male subgroups. Females associated most consistently with other females, although not to the same extent as some males. Female associations were better described as a network rather than discrete subgroups. Male-female associations were generally inconsistent and depended in part on female reproductive state. Mothers and their offspring associated very consistently for at least 4 years.",
    url = "https://doi.org/10.1163/156853992x00101",
    doi = "10.1163/156853992x00101",
    openalex = "W2087462880",
    references = "doi10100797814757990957"
}

Wild dolphins are an elusive subject for behavioral studies: How can you 'do a Jane Goodall' on animals usually visible only as a glimpse of rolling dorsal fins heading for the horizon? In this unusual book, two of the best-known scientists in the marine-mammal field have assembled an astonishing variety of discoveries about dolphins. The contributions range from a graduate student's first paper to senior scientists summarizing a lifetime of research. The dolphins they have studied range from tiny spinners to majestic pilot whales, from killer whales to the familiar bottle-nosed dolphin. The research tactics vary just as widely: the researchers have followed dolphins in boats, tracked them from shore, dived among hundreds of them (plus a few sharks) in tuna fishing nets. They have used computers and airplanes, genetic analysis and artificial language, and learned to read the life history of a dolphin from the cross-section of a single tooth. Pryor and Norris are successful writers as well as scientists; the book is peppered with entertaining essays, by one or both editors, on the intriguing history of dolphin research. Dolphin Societies not only surveys the most interesting recent research on dolphin behavior but also gives lay readers a fascinating look at the scientific mind at work.

@article{doi105860choice293894,
    title = "Dolphin societies: discoveries and puzzles",
    year = "1992",
    journal = "Choice Reviews Online",
    abstract = "Wild dolphins are an elusive subject for behavioral studies: How can you 'do a Jane Goodall' on animals usually visible only as a glimpse of rolling dorsal fins heading for the horizon? In this unusual book, two of the best-known scientists in the marine-mammal field have assembled an astonishing variety of discoveries about dolphins. The contributions range from a graduate student's first paper to senior scientists summarizing a lifetime of research. The dolphins they have studied range from tiny spinners to majestic pilot whales, from killer whales to the familiar bottle-nosed dolphin. The research tactics vary just as widely: the researchers have followed dolphins in boats, tracked them from shore, dived among hundreds of them (plus a few sharks) in tuna fishing nets. They have used computers and airplanes, genetic analysis and artificial language, and learned to read the life history of a dolphin from the cross-section of a single tooth. Pryor and Norris are successful writers as well as scientists; the book is peppered with entertaining essays, by one or both editors, on the intriguing history of dolphin research. Dolphin Societies not only surveys the most interesting recent research on dolphin behavior but also gives lay readers a fascinating look at the scientific mind at work.",
    url = "https://doi.org/10.5860/choice.29-3894",
    doi = "10.5860/choice.29-3894",
    openalex = "W1554834153"
}

@book{doi1010079781461243564,
    author = "Au, Whitlow W. L.",
    title = "The Sonar of Dolphins",
    year = "1993",
    url = "https://doi.org/10.1007/978-1-4612-4356-4",
    doi = "10.1007/978-1-4612-4356-4",
    openalex = "W4239951935"
}

Stomach contents of a resident community of bottlenose dolphins (Tursiops truncatus) from the Sarasota Bay area of the westcentral coast of Florida were studied to examine potential factors leading to patterns of habitat use. Composition and size of prey were analyzed and correlated with feeding behavior of individual dolphins of known histories. Examination of stomach contents of 16 stranded dolphins revealed a diet composed exclusively of fish (15 species), most of which were associated with seagrasses in varying degrees. Observational records for 21 years showed that feeding typically occurred in shallow (2–3 m) waters and in the vicinity of seagrasses in 23% of cases. Dolphins usually fed alone or in small groups and on non-obligate schooling prey. The main species of prey were soniferous, an indication that passive listening may be important in detection of prey. The close agreement between species of fishes represented in stomach contents and habitat of prey, as indicated by observations of feeding, suggests that analysis of stomach contents is a reasonable approach for studying prey and feeding patterns of dolphins. Meadows of seagrass are one of the habitats of importance to dolphins in the Sarasota Bay area, and their protection is important for conservation of these animals.

@article{doi1023071383114,
    author = "Barros, Nélio B. and Wells, Randall S. and Barros, Nélio B.",
    title = "Prey and Feeding Patterns of Resident Bottlenose Dolphins (Tursiops truncatus) in Sarasota Bay, Florida",
    year = "1998",
    journal = "Journal of Mammalogy",
    abstract = "Stomach contents of a resident community of bottlenose dolphins (Tursiops truncatus) from the Sarasota Bay area of the westcentral coast of Florida were studied to examine potential factors leading to patterns of habitat use. Composition and size of prey were analyzed and correlated with feeding behavior of individual dolphins of known histories. Examination of stomach contents of 16 stranded dolphins revealed a diet composed exclusively of fish (15 species), most of which were associated with seagrasses in varying degrees. Observational records for 21 years showed that feeding typically occurred in shallow (2–3 m) waters and in the vicinity of seagrasses in 23\% of cases. Dolphins usually fed alone or in small groups and on non-obligate schooling prey. The main species of prey were soniferous, an indication that passive listening may be important in detection of prey. The close agreement between species of fishes represented in stomach contents and habitat of prey, as indicated by observations of feeding, suggests that analysis of stomach contents is a reasonable approach for studying prey and feeding patterns of dolphins. Meadows of seagrass are one of the habitats of importance to dolphins in the Sarasota Bay area, and their protection is important for conservation of these animals.",
    url = "https://doi.org/10.2307/1383114",
    doi = "10.2307/1383114",
    openalex = "W2071658629"
}

@article{doi101006anbe19980961,
    author = "Sayigh, Laela S. and Tyack, Peter L. and Wells, Randall S. and Solow, Andrew R. and Scott, Michael and Irvine, A. Blair",
    title = "Individual recognition in wild bottlenose dolphins: a field test using playback experiments",
    year = "1999",
    journal = "Animal Behaviour",
    url = "https://doi.org/10.1006/anbe.1998.0961",
    doi = "10.1006/anbe.1998.0961",
    openalex = "W2131462529",
    references = "doi101002sici109746871996062283223aidjmor130co23"
}

Abstract Newborn characteristics, patterns of motoric and social behavioural development, and mother-infant relationships in free-ranging and semi-provisioned bottlenose dolphins (Tursiops sp.) are examined. Nine newborns were observed for 189 hours over the first 10 weeks of life. Newborn infants breathe more often than their mothers, and synchronize their breathing and swimming with her soon after birth, but show a gradual decline in synchrony as they age. Virtually all patterns of infant behaviour, mother-infant proximity, and spatial relationships with the mother changed as a function of infant age. Maternal activity, however, does not change over time, except that mothers decrease their role in maintaining proximity to their infants from the first month to the second month of infant life. Infants spend less time close to their mothers, less time echelon swimming (close, alongside the mother), and more time infant-position swimming (in contact under the mother) as they age. Infants spend more time traveling and socializing independently over time. They also separate from their mothers more often and for longer periods of time. Infants do not forage during the newborn period, but are observed 'practice foraging' by the end of the first month. Rubbing, petting, chasing, and displaying with other animals (including the mother) were common forms of socializing. Infants frequently initiate rubbing with their mothers, with particular focus on her head region. Infants typically associate with young females, adult females and other infants, but not with adult or subadult males. Developmental shifts and overall patterns are discussed in the context of the bottlenose dolphin's fission-fusion social organization and ecology. The effects of provisioning on dolphin behaviour are addressed.

@article{doi101163156853999501469,
    author = "Barbara, Janet Mann",
    title = "BEHAVIORAL DEVELOPMENT IN WILD BOTTLENOSE DOLPHIN NEWBORNS (TURSIOPS SP.)",
    year = "1999",
    journal = "Behaviour",
    abstract = "Abstract Newborn characteristics, patterns of motoric and social behavioural development, and mother-infant relationships in free-ranging and semi-provisioned bottlenose dolphins (Tursiops sp.) are examined. Nine newborns were observed for 189 hours over the first 10 weeks of life. Newborn infants breathe more often than their mothers, and synchronize their breathing and swimming with her soon after birth, but show a gradual decline in synchrony as they age. Virtually all patterns of infant behaviour, mother-infant proximity, and spatial relationships with the mother changed as a function of infant age. Maternal activity, however, does not change over time, except that mothers decrease their role in maintaining proximity to their infants from the first month to the second month of infant life. Infants spend less time close to their mothers, less time echelon swimming (close, alongside the mother), and more time infant-position swimming (in contact under the mother) as they age. Infants spend more time traveling and socializing independently over time. They also separate from their mothers more often and for longer periods of time. Infants do not forage during the newborn period, but are observed 'practice foraging' by the end of the first month. Rubbing, petting, chasing, and displaying with other animals (including the mother) were common forms of socializing. Infants frequently initiate rubbing with their mothers, with particular focus on her head region. Infants typically associate with young females, adult females and other infants, but not with adult or subadult males. Developmental shifts and overall patterns are discussed in the context of the bottlenose dolphin's fission-fusion social organization and ecology. The effects of provisioning on dolphin behaviour are addressed.",
    url = "https://doi.org/10.1163/156853999501469",
    doi = "10.1163/156853999501469",
    openalex = "W1980412926",
    references = "doi101111j174876921999tb00784x"
}

We used a case study of a coastal bottlenose dolphin population to present a framework for determining the number of individuals present and assessing the likely time scale over which trends in abundance may be determined. Such a framework is appropriate for animal species that possess natural markings sufficient for individual recognition, and may be valuable in the development and implementation of management and monitoring programs for vulnerable populations. Population abundance was estimated using mark–recapture methods applied to photoidentification data. This experiment was designed to minimize violation of method assumptions so as to allow use of the most parsimonious model for analysis. The data were examined critically to investigate mark–recapture assumptions, while analytical methods and data were selected to minimize and, where necessary, account for violations. The estimated number of animals with long-lasting marks from left and right side estimates were 73 ± 12 and 80 ± 11 individuals, respectively (means ± 1 se). When divided by the estimated proportion of such animals in the population (0.57 ± 0.043 and 0.61 ± 0.035, respectively) and averaged, weighted by inverse variance, a total population size of 129 ± 15 individual animals was estimated (95% ci = 110–174 animals). Data on calves observed and carcasses recovered suggest that the population could be increasing or decreasing at an annual rate of up to 5%. A power analysis, undertaken to investigate the length of monitoring program required to detect changes in population abundance at a 90% level of certainty, showed that detection of a trend could only occur following >8 yr of research effort. Biennial sampling has power similar to that of annual sampling, but savings in resources are offset by the loss of data on the reproductive histories of individuals.

@article{doi1018901051076119990090288esaati20co2,
    author = "Wilson, Ben and Hammond, Philip S. and Thompson, Paul M.",
    title = "ESTIMATING SIZE AND ASSESSING TRENDS IN A COASTAL BOTTLENOSE DOLPHIN POPULATION",
    year = "1999",
    journal = "Ecological Applications",
    abstract = "We used a case study of a coastal bottlenose dolphin population to present a framework for determining the number of individuals present and assessing the likely time scale over which trends in abundance may be determined. Such a framework is appropriate for animal species that possess natural markings sufficient for individual recognition, and may be valuable in the development and implementation of management and monitoring programs for vulnerable populations. Population abundance was estimated using mark–recapture methods applied to photoidentification data. This experiment was designed to minimize violation of method assumptions so as to allow use of the most parsimonious model for analysis. The data were examined critically to investigate mark–recapture assumptions, while analytical methods and data were selected to minimize and, where necessary, account for violations. The estimated number of animals with long-lasting marks from left and right side estimates were 73 ± 12 and 80 ± 11 individuals, respectively (means ± 1 se). When divided by the estimated proportion of such animals in the population (0.57 ± 0.043 and 0.61 ± 0.035, respectively) and averaged, weighted by inverse variance, a total population size of 129 ± 15 individual animals was estimated (95\% ci = 110–174 animals). Data on calves observed and carcasses recovered suggest that the population could be increasing or decreasing at an annual rate of up to 5\%. A power analysis, undertaken to investigate the length of monitoring program required to detect changes in population abundance at a 90\% level of certainty, showed that detection of a trend could only occur following >8 yr of research effort. Biennial sampling has power similar to that of annual sampling, but savings in resources are offset by the loss of data on the reproductive histories of individuals.",
    url = "https://doi.org/10.1890/1051-0761(1999)009[0288:esaati]2.0.co;2",
    doi = "10.1890/1051-0761(1999)009[0288:esaati]2.0.co;2",
    openalex = "W2087465283",
    references = "doi10100797814757990957"
}

@incollection{doi10100797814612115014,
    author = "Tyack, Peter L. and Clark, Christopher W.",
    title = "Communication and Acoustic Behavior of Dolphins and Whales",
    year = "2000",
    booktitle = "Springer handbook of auditory research",
    url = "https://doi.org/10.1007/978-1-4612-1150-1\_4",
    doi = "10.1007/978-1-4612-1150-1\_4",
    openalex = "W42620",
    references = "doi101002sici109746871996062283223aidjmor130co23, doi101016030096299290314g"
}

This study examines factors influencing female reproductive success in wild Indian Ocean bottlenose dolphins (Tursiops sp.) in Shark Bay, Australia. Eighty-three females and their 142 calves were surveyed between 1988 and 1998 (3457 surveys); 42 calves were also observed during focal follows for 1330 h. Calf mortality is 44% by age 3 (n = 110). 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. Accordingly, median interbirth interval was 4.1 years. Female reproductive success was classified as 0, 1, 2, or 3 according to the number of calves who survived to age 3 over a 10-year period (n = 38 females with complete histories). We examined whether factors affecting predation or food availability, water depth, and group size, were related to female reproductive success. Group size was unrelated to water depth or female reproductive success, but reproductive success was predicted by water depth (p <.002). 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.

@article{doi101093beheco112210,
    author = "Mann, Janet",
    title = "Female reproductive success in bottlenose dolphins (Tursiops sp.): life history, habitat, provisioning, and group-size effects",
    year = "2000",
    journal = "Behavioral Ecology",
    abstract = "This study examines factors influencing female reproductive success in wild Indian Ocean bottlenose dolphins (Tursiops sp.) in Shark Bay, Australia. Eighty-three females and their 142 calves were surveyed between 1988 and 1998 (3457 surveys); 42 calves were also observed during focal follows for 1330 h. Calf mortality is 44\% by age 3 (n = 110). 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. Accordingly, median interbirth interval was 4.1 years. Female reproductive success was classified as 0, 1, 2, or 3 according to the number of calves who survived to age 3 over a 10-year period (n = 38 females with complete histories). We examined whether factors affecting predation or food availability, water depth, and group size, were related to female reproductive success. Group size was unrelated to water depth or female reproductive success, but reproductive success was predicted by water depth (p <.002). 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.",
    url = "https://doi.org/10.1093/beheco/11.2.210",
    doi = "10.1093/beheco/11.2.210",
    openalex = "W2113027920",
    references = "doi10100797814757990957"
}

Studies of animal culture have not normally included a consideration of cetaceans. However, with several long-term field studies now maturing, this situation should change. Animal culture is generally studied by either investigating transmission mechanisms experimentally, or observing patterns of behavioural variation in wild populations that cannot be explained by either genetic or environmental factors. Taking this second, ethnographic, approach, there is good evidence for cultural transmission in several cetacean species. However, only the bottlenose dolphin (Tursiops) has been shown experimentally to possess sophisticated social learning abilities, including vocal and motor imitation; other species have not been studied. There is observational evidence for imitation and teaching in killer whales. For cetaceans and other large, wide-ranging animals, excessive reliance on experimental data for evidence of culture is not productive; we favour the ethnographic approach. The complex and stable vocal and behavioural cultures of sympatric groups of killer whales (Orcinus orca) appear to have no parallel outside humans, and represent an independent evolution of cultural faculties. The wide movements of cetaceans, the greater variability of the marine environment over large temporal scales relative to that on land, and the stable matrilineal social groups of some species are potentially important factors in the evolution of cetacean culture. There have been suggestions of gene-culture coevolution in cetaceans, and culture may be implicated in some unusual behavioural and life-history traits of whales and dolphins. We hope to stimulate discussion and research on culture in these animals.

@article{doi101017s0140525x0100396x,
    author = "Rendell, Luke and Whitehead, Hal",
    title = "Culture in whales and dolphins",
    year = "2001",
    journal = "Behavioral and Brain Sciences",
    abstract = "Studies of animal culture have not normally included a consideration of cetaceans. However, with several long-term field studies now maturing, this situation should change. Animal culture is generally studied by either investigating transmission mechanisms experimentally, or observing patterns of behavioural variation in wild populations that cannot be explained by either genetic or environmental factors. Taking this second, ethnographic, approach, there is good evidence for cultural transmission in several cetacean species. However, only the bottlenose dolphin (Tursiops) has been shown experimentally to possess sophisticated social learning abilities, including vocal and motor imitation; other species have not been studied. There is observational evidence for imitation and teaching in killer whales. For cetaceans and other large, wide-ranging animals, excessive reliance on experimental data for evidence of culture is not productive; we favour the ethnographic approach. The complex and stable vocal and behavioural cultures of sympatric groups of killer whales (Orcinus orca) appear to have no parallel outside humans, and represent an independent evolution of cultural faculties. The wide movements of cetaceans, the greater variability of the marine environment over large temporal scales relative to that on land, and the stable matrilineal social groups of some species are potentially important factors in the evolution of cetacean culture. There have been suggestions of gene-culture coevolution in cetaceans, and culture may be implicated in some unusual behavioural and life-history traits of whales and dolphins. We hope to stimulate discussion and research on culture in these animals.",
    url = "https://doi.org/10.1017/s0140525x0100396x",
    doi = "10.1017/s0140525x0100396x",
    openalex = "W2153418948",
    references = "doi101016004724849290081j, doi101017s0140525x00076512, doi101098rspb19790081, doi101111j155856461957tb02911x, doi101111j155856461995tb04464x, doi101111j174876921999tb00784x, doi101126science28654492526, doi102307jctvw1d7dg9, doi105860choice351500, doi105860choice370272, openalexw2624262714"
}

Although both food availability and predation risk have been hypothesized to affect dolphin habitat use and group size, no study has measured both factors concurrently to determine their relative influences. From 1997 to 1999, we investigated the effect of food availability and tiger shark (Galeocerdo cuvier) predation risk on bottlenose dolphin (Tursiops aduncus) habitat use and group size in Shark Bay, Western Australia. Food availability was measured by fish trapping, while predation risk was assessed by shark catch rates, acoustic tracks, and Crittercam deployments. Dolphin habitat use was determined using belt transects. The biomass of dolphin prey did not vary seasonally and was significantly greater in shallow habitats than in deeper ones. Tiger sharks were virtually absent during cold months of 1997 and 1998, abundant in warm months of all years, and found at an intermediate density during cold months of 1999. When present, shark density was highest in shallow habitats. Decreased echolocation efficiency in very shallow water and poor visual detection of tiger sharks (camouflaged over seagrass) probably further enhance the riskiness of such habitats, and the relative riskiness of shallow habitats is supported by the observation that dolphins select deep waters in which to rest. The observed dolphin group sizes were consistent with a food–safety trade-off. Groups were larger in more dangerous shallow habitats and larger during resting than during foraging. Foraging dolphins matched the distribution of their food when sharks were absent. However, during warm months, the distribution of foraging dolphins significantly deviated from that of their food, with fewer dolphins foraging in the productive (but dangerous) shallow habitats than expected on the basis of food alone. When shark density was intermediate, habitat use by foraging dolphins was more similar to the high-shark-density seasons than periods of low shark density. These results suggest that foraging dolphin distributions reflect a trade-off between predation risk and food availability. Because the distribution and abundance of tiger sharks are influenced by species other than dolphins, the distribution of the tiger sharks' primary prey may indirectly influence dolphin habitat use, suggesting that it is important to consider the community context in studies of habitat use.

@article{doi1018900012965820020830480faatsp20co2,
    author = "Heithaus, Michael R. and Dill, Lawrence M.",
    title = "FOOD AVAILABILITY AND TIGER SHARK PREDATION RISK INFLUENCE BOTTLENOSE DOLPHIN HABITAT USE",
    year = "2002",
    journal = "Ecology",
    abstract = "Although both food availability and predation risk have been hypothesized to affect dolphin habitat use and group size, no study has measured both factors concurrently to determine their relative influences. From 1997 to 1999, we investigated the effect of food availability and tiger shark (Galeocerdo cuvier) predation risk on bottlenose dolphin (Tursiops aduncus) habitat use and group size in Shark Bay, Western Australia. Food availability was measured by fish trapping, while predation risk was assessed by shark catch rates, acoustic tracks, and Crittercam deployments. Dolphin habitat use was determined using belt transects. The biomass of dolphin prey did not vary seasonally and was significantly greater in shallow habitats than in deeper ones. Tiger sharks were virtually absent during cold months of 1997 and 1998, abundant in warm months of all years, and found at an intermediate density during cold months of 1999. When present, shark density was highest in shallow habitats. Decreased echolocation efficiency in very shallow water and poor visual detection of tiger sharks (camouflaged over seagrass) probably further enhance the riskiness of such habitats, and the relative riskiness of shallow habitats is supported by the observation that dolphins select deep waters in which to rest. The observed dolphin group sizes were consistent with a food–safety trade-off. Groups were larger in more dangerous shallow habitats and larger during resting than during foraging. Foraging dolphins matched the distribution of their food when sharks were absent. However, during warm months, the distribution of foraging dolphins significantly deviated from that of their food, with fewer dolphins foraging in the productive (but dangerous) shallow habitats than expected on the basis of food alone. When shark density was intermediate, habitat use by foraging dolphins was more similar to the high-shark-density seasons than periods of low shark density. These results suggest that foraging dolphin distributions reflect a trade-off between predation risk and food availability. Because the distribution and abundance of tiger sharks are influenced by species other than dolphins, the distribution of the tiger sharks' primary prey may indirectly influence dolphin habitat use, suggesting that it is important to consider the community context in studies of habitat use.",
    url = "https://doi.org/10.1890/0012-9658(2002)083[0480:faatsp]2.0.co;2",
    doi = "10.1890/0012-9658(2002)083[0480:faatsp]2.0.co;2",
    openalex = "W2124577949",
    references = "doi10100797814757990957, doi101007s0022700107117, doi1010160040580977900429, doi101016s0169534799017231, doi101086284280, doi101086285208, doi101086285880, doi101139z90092, doi1023071939877, doi1023071941633, openalexw631077730"
}

@article{doi101007s002650030651y,
    author = "Lusseau, David and Schneider, Karsten and Boisseau, Oliver and Haase, Patti A. and Slooten, Elisabeth and Dawson, Steve",
    title = "The bottlenose dolphin community of Doubtful Sound features a large proportion of long-lasting associations",
    year = "2003",
    journal = "Behavioral Ecology and Sociobiology",
    url = "https://doi.org/10.1007/s00265-003-0651-y",
    doi = "10.1007/s00265-003-0651-y",
    openalex = "W2094234423",
    references = "doi10100797814757990957"
}

A bstract Watercraft may provide the greatest source of anthropogenic noise for bottlenose dolphins living in coastal waters. A resident community of about 140 individuals near Sarasota, Florida, are exposed to a vessel passing within 100 m approximately every six minutes during daylight hours. I investigated the circumstances under which watercraft traffic may impact the acoustic behavior of this community, specifically looking for short‐term changes in whistle frequency range, duration, and rate of production. To analyze whistles and received watercraft noise levels, acoustic recordings were made using two hydrophones towed from an observation vessel during focal animal follows of 14 individual dolphins. The duration and frequency range of signature whistles did not change significantly relative to vessel approaches. However, dolphins whistled significantly more often at the onset of approaches compared to during and after vessel approaches. Whistle rate was also significantly greater at the onset of a vessel approach than when no vessels were present. Increased whistle repetition as watercraft approach may simply reflect heightened arousal, an increased motivation for animals to come closer together, with whistles functioning to promote reunions. It may also be an effective way to compensate for signal masking, maintaining communication in a noisy environment.

@article{doi101111j174876922004tb01189x,
    author = "Buckstaff, Kara",
    title = "EFFECTS OF WATERCRAFT NOISE ON THE ACOUSTIC BEHAVIOR OF BOTTLENOSE DOLPHINS, TURSIOPS TRUNCATUS, IN SARASOTA BAY, FLORIDA",
    year = "2004",
    journal = "Marine Mammal Science",
    abstract = "A bstract Watercraft may provide the greatest source of anthropogenic noise for bottlenose dolphins living in coastal waters. A resident community of about 140 individuals near Sarasota, Florida, are exposed to a vessel passing within 100 m approximately every six minutes during daylight hours. I investigated the circumstances under which watercraft traffic may impact the acoustic behavior of this community, specifically looking for short‐term changes in whistle frequency range, duration, and rate of production. To analyze whistles and received watercraft noise levels, acoustic recordings were made using two hydrophones towed from an observation vessel during focal animal follows of 14 individual dolphins. The duration and frequency range of signature whistles did not change significantly relative to vessel approaches. However, dolphins whistled significantly more often at the onset of approaches compared to during and after vessel approaches. Whistle rate was also significantly greater at the onset of a vessel approach than when no vessels were present. Increased whistle repetition as watercraft approach may simply reflect heightened arousal, an increased motivation for animals to come closer together, with whistles functioning to promote reunions. It may also be an effective way to compensate for signal masking, maintaining communication in a noisy environment.",
    url = "https://doi.org/10.1111/j.1748-7692.2004.tb01189.x",
    doi = "10.1111/j.1748-7692.2004.tb01189.x",
    openalex = "W2080010639",
    references = "doi101111j174876921999tb00782x, doi101111j174876921999tb00784x"
}

In Shark Bay, wild bottlenose dolphins (Tursiops sp.) apparently use marine sponges as foraging tools. We demonstrate that genetic and ecological explanations for this behavior are inadequate; thus, "sponging" classifies as the first case of an existing material culture in a marine mammal species. Using mitochondrial DNA analyses, we show that sponging shows an almost exclusive vertical social transmission within a single matriline from mother to female offspring. Moreover, significant genetic relatedness among all adult spongers at the nuclear level indicates very recent coancestry, suggesting that all spongers are descendents of one recent "Sponging Eve." Unlike in apes, tool use in this population is almost exclusively limited to a single matriline that is part of a large albeit open social network of frequently interacting individuals, adding a new dimension to charting cultural phenomena among animals.

@article{doi101073pnas0500232102,
    author = "Krützen, Michael and Mann, Janet and Heithaus, Michael R. and Connor, Richard C. and Bejder, Lars and Sherwin, William B.",
    title = "Cultural transmission of tool use in bottlenose dolphins",
    year = "2005",
    journal = "Proceedings of the National Academy of Sciences",
    abstract = {In Shark Bay, wild bottlenose dolphins (Tursiops sp.) apparently use marine sponges as foraging tools. We demonstrate that genetic and ecological explanations for this behavior are inadequate; thus, "sponging" classifies as the first case of an existing material culture in a marine mammal species. Using mitochondrial DNA analyses, we show that sponging shows an almost exclusive vertical social transmission within a single matriline from mother to female offspring. Moreover, significant genetic relatedness among all adult spongers at the nuclear level indicates very recent coancestry, suggesting that all spongers are descendents of one recent "Sponging Eve." Unlike in apes, tool use in this population is almost exclusively limited to a single matriline that is part of a large albeit open social network of frequently interacting individuals, adding a new dimension to charting cultural phenomena among animals.},
    url = "https://doi.org/10.1073/pnas.0500232102",
    doi = "10.1073/pnas.0500232102",
    openalex = "W2054949188",
    references = "doi101017s0140525x0100396x, doi10103821415, doi101093oxfordjournalsjhereda111627, doi101111j155856461984tb05657x, doi101111j155856461989tb04226x, doi101126science1078004, doi101163156853974x00534, doi1023071938423, openalexw2062594085, openalexw2330569226"
}

Studies evaluating effects of human activity on wildlife typically emphasize short-term behavioral responses from which it is difficult to infer biological significance or formulate plans to mitigate harmful impacts. Based on decades of detailed behavioral records, we evaluated long-term impacts of vessel activity on bottlenose dolphins (Tursiops sp.) in Shark Bay, Australia. We compared dolphin abundance within adjacent 36-km2 tourism and control sites, over three consecutive 4.5-year periods wherein research activity was relatively constant but tourism levels increased from zero, to one, to two dolphin-watching operators. A nonlinear logistic model demonstrated that there was no difference in dolphin abundance between periods with no tourism and periods in which one operator offered tours. As the number of tour operators increased to two, there was a significant average decline in dolphin abundance (14.9%; 95% CI=-20.8 to -8.23), approximating a decline of one per seven individuals. Concurrently, within the control site, the average increase in dolphin abundance was not significant (8.5%; 95% CI=-4.0 to +16.7). Given the substantially greater presence and proximity of tour vessels to dolphins relative to research vessels, tour-vessel activity contributed more to declining dolphin numbers within the tourism site than research vessels. Although this trend may not jeopardize the large, genetically diverse dolphin population of Shark Bay, the decline is unlikely to be sustainable for local dolphin tourism. A similar decline would be devastating for small, closed, resident, or endangered cetacean populations. The substantial effect of tour vessels on dolphin abundance in a region of low-level tourism calls into question the presumption that dolphin-watching tourism is benign.

@article{doi101111j15231739200600540x,
    author = "Bejder, Lars and Samuels, Amy and Whitehead, Hal and Gales, Nick and Mann, Janet and Connor, Richard C. and HEITHAUS, MIKE and Watson-Capps, Jana J. and Flaherty, Cindy and Krützen, Michael",
    title = "Decline in Relative Abundance of Bottlenose Dolphins Exposed to Long‐Term Disturbance",
    year = "2006",
    journal = "Conservation Biology",
    abstract = "Studies evaluating effects of human activity on wildlife typically emphasize short-term behavioral responses from which it is difficult to infer biological significance or formulate plans to mitigate harmful impacts. Based on decades of detailed behavioral records, we evaluated long-term impacts of vessel activity on bottlenose dolphins (Tursiops sp.) in Shark Bay, Australia. We compared dolphin abundance within adjacent 36-km2 tourism and control sites, over three consecutive 4.5-year periods wherein research activity was relatively constant but tourism levels increased from zero, to one, to two dolphin-watching operators. A nonlinear logistic model demonstrated that there was no difference in dolphin abundance between periods with no tourism and periods in which one operator offered tours. As the number of tour operators increased to two, there was a significant average decline in dolphin abundance (14.9\%; 95\% CI=-20.8 to -8.23), approximating a decline of one per seven individuals. Concurrently, within the control site, the average increase in dolphin abundance was not significant (8.5\%; 95\% CI=-4.0 to +16.7). Given the substantially greater presence and proximity of tour vessels to dolphins relative to research vessels, tour-vessel activity contributed more to declining dolphin numbers within the tourism site than research vessels. Although this trend may not jeopardize the large, genetically diverse dolphin population of Shark Bay, the decline is unlikely to be sustainable for local dolphin tourism. A similar decline would be devastating for small, closed, resident, or endangered cetacean populations. The substantial effect of tour vessels on dolphin abundance in a region of low-level tourism calls into question the presumption that dolphin-watching tourism is benign.",
    url = "https://doi.org/10.1111/j.1523-1739.2006.00540.x",
    doi = "10.1111/j.1523-1739.2006.00540.x",
    openalex = "W2132750032",
    references = "doi10100797814757990957, doi101016c20090022533, doi101016s0006320700000021, doi101093beheco112210, doi101098rsbl20040225, doi101111j00218901200400900x, doi101111j174876921999tb00784x, doi101139z90092, doi101163156853992x00101, doi105751es00404060111"
}

@article{doi101007s0022700913712,
    author = "McCabe, Elizabeth J. Berens and Gannon, Damon P. and Barros, Nélio B. and Wells, Randall S.",
    title = "Prey selection by resident common bottlenose dolphins (tursiops truncatus) in Sarasota Bay, Florida",
    year = "2009",
    journal = "Marine Biology",
    url = "https://doi.org/10.1007/s00227-009-1371-2",
    doi = "10.1007/s00227-009-1371-2",
    openalex = "W1998165517"
}

@article{doi101016jbiocon201411003,
    author = "Pirotta, Enrico and Merchant, Nathan D. and Thompson, Paul M. and Barton, Tim R. and Lusseau, David",
    title = "Quantifying the effect of boat disturbance on bottlenose dolphin foraging activity",
    year = "2014",
    journal = "Biological Conservation",
    url = "https://doi.org/10.1016/j.biocon.2014.11.003",
    doi = "10.1016/j.biocon.2014.11.003",
    openalex = "W1990553134",
    references = "doi101098rspb20042863, doi101111j174876921999tb00784x"
}

@article{doi101038s4159802649771x,
    author = "Swinehart, Andrea L and Valencia, Ana K Nader and Cook, Kristin L and Lentz, Nadia J and Gibson, Quincy A",
    title = "Novel prey item identified for estuarine bottlenose dolphins (Tursiops erebennus) in the Southeastern United States.",
    year = "2026",
    journal = "Scientific reports",
    url = "https://pubmed.ncbi.nlm.nih.gov/42020502/",
    doi = "10.1038/s41598-026-49771-x",
    openalex = "W7155211551",
    pmid = "42020502",
    references = "doi101007s0022700913712, doi101016jjembe201109009, doi101016s0025326x0100323x, doi101093icesjmsfsu187, doi101111j174876921986tb00026x, doi101126sciadv1501769, doi1011399780660191089, doi101146annurevecolsys33010802150515, doi1011770300985810388525, doi1023071383114"
}