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Palmer EI, Betty EL, Murphy S, Perrott MR, Smith ANH, Stockin KA. Reproductive biology of male common dolphins ( Delphinus delphis) in New Zealand waters. MARINE BIOLOGY 2023; 170:153. [PMID: 37811127 PMCID: PMC10558376 DOI: 10.1007/s00227-023-04266-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Accepted: 08/02/2023] [Indexed: 10/10/2023]
Abstract
Reproductive parameters were assessed in 64 male common dolphins (Delphinus delphis) examined post-mortem from strandings and bycatch in New Zealand between 1999 and 2020. The stages of male sexual maturation were assessed using morphological measurements and histological examination of testicular tissue. Age was determined via growth layer groups (GLGs) in teeth. The average age (ASM) and length (LSM) at attainment of sexual maturity were estimated to be 8.8 years and 198.3 cm, respectively. Individual variation in ASM (7.5-10 years) and LSM (190-220 cm) was observed in New Zealand common dolphins. However, on average, sexual maturity was attained at a similar length but at a marginally younger age (< 1 year) in New Zealand compared to populations in the Northern Hemisphere. All testicular variables proved better predictors of sexual maturity compared to demographic variables (age and total body length), with combined testes weight the best outright predictor of sexual maturity. Reproductive seasonality was observed in male common dolphins, with a significant increase in combined testes weight in austral summer. This aligns with most other studied populations, where seasonality in reproduction is typically observed. Given the known anthropogenic impacts on New Zealand common dolphins, we recommend that these findings be used as a baseline from which to monitor population-level changes as part of conservation management efforts. Supplementary Information The online version contains supplementary material available at 10.1007/s00227-023-04266-5.
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Affiliation(s)
- Emily I. Palmer
- Cetacean Ecology Research Group, School of Natural Sciences, Massey University, 0745 Auckland, New Zealand
| | - Emma L. Betty
- Cetacean Ecology Research Group, School of Natural Sciences, Massey University, 0745 Auckland, New Zealand
| | - Sinéad Murphy
- Marine and Freshwater Research Centre, Department of Natural Resources & the Environment, School of Science and Computing, Atlantic Technological University, ATU Galway City, Old Dublin Road, Galway, H91 T8NW Ireland
| | - Matthew R. Perrott
- School of Veterinary Sciences, Massey University, Palmerston North, New Zealand
| | - Adam N. H. Smith
- School of Mathematical and Computational Sciences, Massey University, 0745 Auckland, New Zealand
| | - Karen A. Stockin
- Cetacean Ecology Research Group, School of Natural Sciences, Massey University, 0745 Auckland, New Zealand
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Uchida K, Burkle AA, Blumstein DT. Take only pictures, leave only… Cameras influence marmot vigilance but not perceptions of risk. J Zool (1987) 2022. [DOI: 10.1111/jzo.13032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- K. Uchida
- Department of Ecology & Evolutionary Biology University of California Los Angeles CA USA
- Graduate School of Agricultural and Life Sciences The University of Tokyo Tokyo Japan
| | - A. A. Burkle
- Department of Biology Western Colorado University Gunnison CO USA
- The Rocky Mountain Biological Laboratory Crested Butte CO USA
| | - D. T. Blumstein
- Department of Ecology & Evolutionary Biology University of California Los Angeles CA USA
- The Rocky Mountain Biological Laboratory Crested Butte CO USA
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Evaluating Potential Cetacean Welfare Indicators from Video of Live Stranded Long-Finned Pilot Whales ( Globicephala melas edwardii). Animals (Basel) 2022; 12:ani12141861. [PMID: 35883407 PMCID: PMC9312325 DOI: 10.3390/ani12141861] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Revised: 07/16/2022] [Accepted: 07/18/2022] [Indexed: 01/11/2023] Open
Abstract
Despite the known benefit of considering welfare within wildlife conservation and management, there remains a lack of data to inform such evaluations. To assess animal welfare, relevant information must be captured scientifically and systematically. A key first step is identifying potential indicators of welfare and the practicality of their measurement. We assessed the feasibility of evaluating potential welfare indicators from opportunistically gathered video footage of four stranded odontocete species (n = 53) at 14 stranding events around New Zealand. The first stranded cetacean ethogram was compiled, including 30 different behaviours, 20 of which were observed in all four species. Additionally, thirteen types of human intervention were classified. A subset of 49 live stranded long-finned pilot whales (Globicephala melas edwardii) were assessed to determine indicator prevalence and to quantify behaviours. Four ‘welfare status’ and six ‘welfare alerting’ non-behavioural indicators could be consistently evaluated from the footage. Additionally, two composite behavioural indicators were feasible. Three human intervention types (present, watering, and touching) and five animal behaviours (tail flutter, dorsal fin flutter, head lift, tail lift, and head side-to-side) were prevalent (>40% of individuals). Our study highlights the potential for non-invasive, remote assessments via video footage and represents an initial step towards developing a systematic, holistic welfare assessment framework for stranded cetaceans.
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Behavioral Pattern of Risso’s Dolphin (Grampus griseus) in the Gulf of Taranto (Northern Ionian Sea, Central-Eastern Mediterranean Sea). JOURNAL OF MARINE SCIENCE AND ENGINEERING 2022. [DOI: 10.3390/jmse10020175] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Relatively scant information is available on the Risso’s dolphin in comparison to the other species regularly present in the Mediterranean Sea. Recently, its conservation status has been updated to Endangered by the International Union for Conservation of Nature (IUCN) in this Sea. Therefore, the need to increase information on its biology and ecology is even more urgent. This study reports the first preliminary information on the behavioral traits of the species occurring in the Gulf of Taranto (Northern Ionian Sea). Data on predominant behavioral activity states and on a set of group composition variables (group formation, cruising speed, dive duration and interaction between individuals) were collected from April 2019 to September 2021, applying the focal-group protocol with instantaneous scan sampling. Group size, depth and group composition variables were compared between activity states. Results highlight that both the group size and the several variables considered varied significantly depending on activity state. The group size was significantly smaller during feeding than resting and traveling and a characterization in terms of group formation, cruise speed, dive duration and interaction between animals is provided for the different activity states. Moreover, a list of behavioral events which occurred, as well as their relative frequency of distribution among activity states, is reported. Finally, details on the sympatric occurrences between Risso’s and striped dolphins, as well as the repetitive interaction observed between adult individuals and plastic bags floating on the sea surface, are reported and discussed.
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Quintana Martín-Montalvo B, Hoarau L, Deffes O, Delaspre S, Delfour F, Landes AE. Dolphin Watching and Compliance to Guidelines Affect Spinner Dolphins' ( Stenella longirostris) Behaviour in Reunion Island. Animals (Basel) 2021; 11:ani11092674. [PMID: 34573639 PMCID: PMC8470298 DOI: 10.3390/ani11092674] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Revised: 08/25/2021] [Accepted: 09/08/2021] [Indexed: 11/30/2022] Open
Abstract
Simple Summary Whale and dolphin watching have expanded worldwide, with their impacts on cetaceans over the short and long terms being widely reported. In Reunion Island, the activity has rapidly developed, notably around a resident spinner dolphin population, which can be seen year-round. Focal follows revealed that the dolphins are less likely to begin socialising or resting and more likely to remain travelling or milling in the presence of dolphin-watching vessels. The dolphins’ avoidance reactions increased when tourist vessels were numerous or in non-compliance with the regulations. The cumulative effect of such behavioural responses likely impacts the dolphins at the population level, highlighting the need for enforcing adaptive and efficient dolphin-watching management measures to ensure the welfare and preservation of the resident spinner dolphins of Reunion Island. Abstract Marine wildlife tourism has rapidly developed in Reunion Island, due to a large demand for interactions with a resident population of spinner dolphins (Stenella longirostris). The presence of dolphin-watching vessels close to dolphin groups can cause short-term impacts on their behaviour; cumulative incidences likely result in deleterious long-term impacts on the population. Using scan sampling, we collected behavioural data on spinner dolphins to evaluate the short-term effects of dolphin watching on their behaviour. The dolphins were less likely to begin socialising or diving while travelling and more likely to stay travelling and milling in the presence of vessels. Additionally, activity budgets for resting and socialising decreased simultaneously with increased travelling and milling. Avoidance responses significantly increased with an increase in the number of vessels and non-compliance with the local dolphin-watching guidelines. These behavioural responses are likely to have energetic costs for the dolphins, which may lead to decreased survival and reproductive success at individual and population levels. More restrictive regulations, increased surveillance and animal-based measures are key tools to adapt the conservation efforts in Reunion Island. Further studies on the island’s resident dolphin populations are necessary to ensure the continuity of dolphin-watching activities in a sustainable manner.
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Affiliation(s)
- Belén Quintana Martín-Montalvo
- Centre d’Etude et Découverte des Tortues Marines (CEDTM), 97424 Piton Saint Leu, France; (O.D.); (S.D.); (A.-E.L.)
- Correspondence:
| | - Ludovic Hoarau
- UMR ENTROPIE, Université de La Réunion, IRD, CNRS, IFREMER, UNC, CEDEX 9, 97744 Saint Denis, France;
| | - Ophélie Deffes
- Centre d’Etude et Découverte des Tortues Marines (CEDTM), 97424 Piton Saint Leu, France; (O.D.); (S.D.); (A.-E.L.)
- Faculté des Sciences et Techniques, Université Jean Monnet, 42100 Saint-Etienne, France
| | - Sylvain Delaspre
- Centre d’Etude et Découverte des Tortues Marines (CEDTM), 97424 Piton Saint Leu, France; (O.D.); (S.D.); (A.-E.L.)
| | | | - Anne-Emmanuelle Landes
- Centre d’Etude et Découverte des Tortues Marines (CEDTM), 97424 Piton Saint Leu, France; (O.D.); (S.D.); (A.-E.L.)
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Keep your distance: Using Instagram posts to evaluate the risk of anthroponotic disease transmission in gorilla ecotourism. PEOPLE AND NATURE 2021. [DOI: 10.1002/pan3.10187] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Assessment on the effectiveness of vessel-approach regulations to protect cetaceans in Australia: A review on behavioral impacts with case study on the threatened Burrunan dolphin (Tursiops australis). PLoS One 2021; 16:e0243353. [PMID: 33465088 PMCID: PMC7815133 DOI: 10.1371/journal.pone.0243353] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2019] [Accepted: 11/19/2020] [Indexed: 12/04/2022] Open
Abstract
Vessels cause considerable disturbance to cetaceans world-wide, with potential long-term impacts to population viability. Here we present a comprehensive review of vessel impacts to cetacean behavior in Australian waters (2003–2015), finding inadequate protections to be in place. The majority of these studies found trends of decreased animal travel and resting behavioral states as well as low compliance to regulations, and they recommended further regulatory action such as greater enforcement or monitoring, or passive management strategies. As a case study, we conducted the first field assessment of vessel compliance with the Wildlife (Marine Mammal) Regulations 2009 in Gippsland Lakes, Australia, and provide the first assessment of the endangered Gippsland Lakes Burrunan dolphin (Tursiops australis) population’s behavioral ecology. Dolphin behavior and vessel regulation compliance data were collected during boat-based surveys of Gippsland Lakes from July 2017 to January 2018, with a total of 22 dolphin group sightings resulting in 477 five-minute point samples. 77% of dolphin sightings involved vessel interactions (within 400 m), and 56 regulation breaches were observed. These breaches were most severe in summer (mean = 4.54 breaches/hour). Vessels were found to alter dolphin behavior before, during, and after interactions and regulation breaches, including increased mating (mate guarding) and milling behavioral states, and increased ‘fish catch’, ‘high leap’ and ‘tail slap’ behavioral events. These behavioral changes may indicate masking of the dolphins' acoustic communication, disturbance of prey, increased dolphin transition behaviors, and/or induced stress and changes to group structure (including increased mate guarding). While our results provide evidence of short-term altered behavior, the potential for long-term effects on population dynamics for this threatened species is high. In the context of reported inadequate cetacean protection Australia-wide, our management recommendations include greater monitoring and enforcement, and the utilisation of adaptive management.
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Instagranimal: Animal Welfare and Animal Ethics Challenges of Animal-Based Tourism. Animals (Basel) 2020; 10:ani10101830. [PMID: 33050024 PMCID: PMC7600185 DOI: 10.3390/ani10101830] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Revised: 10/01/2020] [Accepted: 10/02/2020] [Indexed: 11/16/2022] Open
Abstract
Simple Summary Animals of countless species, wild as well as tame, can now entertain tourists on their holidays. The popularity, however, of animal-based tourism comes with significant risks for the welfare of these animals. Many animals are kept in small confinements, are broken down to interact obediently with tourists, or are made to perform, entertain, transport or even give their lives for human leisure. In this paper, the challenges of animal-based tourism are presented from the perspectives of interdisciplinary researchers. The challenges are discussed based on a two-day symposium with workshop sessions. We bring attention to the problem of cultural relativism and the difficulty of imposing universal standards of animal welfare. We conclude that reforms and individual travel decisions as a result of biosecurity concerns will impact animal welfare. In addition to this, we observe that technology has a dual role to play in enhancing edutainment but also potentially inviting new challenges. In the end, we declare some possibilities for compassionate animal based tourism. Abstract By animal-based tourism, a host of activities offering passive viewing or active interaction with wild, semi-wild or captive animals is included. The multibillion dollar industry is on the rise globally today, offering modes of engagement with animals that trade on increasingly embodied close encounters with non-human animals. As new modes of animal-based tourism proliferate, such as sloth selfies, visiting cat cafes, swimming with sharks and agri-tourism petting zoos, animal welfare standards risk deteriorating. In the following paper, we collate concerns over animal welfare into a discussion on the challenges facing animal-based tourism. Our synthesis is the first to consider the full spectrum of such animal-based tourism: across agri-, hunting, zoo and safari tourism, to name a few, and crossing consumptive and non-consumptive boundaries. A literature review is first provided. Findings are then presented thematically following workshops at an international interdisciplinary symposium of leading tourism, animal welfare, ethics and leisure sciences scholars together with practitioners of the industry. It discusses macrolevel drivers to animal-based tourism as an industry, the problem of cultural relativism and the role of technology in enhancing or promoting the experience. We indicate ways forward toward implementing a compassionate animal-based tourism.
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Kassamali-Fox A, Christiansen F, May-Collado LJ, Ramos EA, Kaplin BA. Tour boats affect the activity patterns of bottlenose dolphins ( Tursiops truncatus) in Bocas del Toro, Panama. PeerJ 2020; 8:e8804. [PMID: 32266117 PMCID: PMC7115753 DOI: 10.7717/peerj.8804] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2019] [Accepted: 02/25/2020] [Indexed: 11/20/2022] Open
Abstract
Bottlenose dolphins (Tursiops truncatus) of the Bocas del Toro archipelago are targeted by the largest boat-based cetacean watching operation in Panama. Tourism is concentrated in Dolphin Bay, home to a population of resident dolphins. Previous studies have shown that tour boats elicit short-term changes in dolphin behavior and communication; however, the relationship of these responses to the local population's biology and ecology is unclear. Studying the effects of tour boats on dolphin activity patterns and behavior can provide information about the biological significance of these responses. Here, we investigated the effects of tour boat activity on bottlenose dolphin activity patterns in Bocas del Toro, Panama over 10 weeks in 2014. Markov chain models were used to assess the effect of tour boats on dolphin behavioral transition probabilities in both control and impact scenarios. Effect of tour boat interactions was quantified by comparing transition probabilities of control and impact chains. Data were also used to construct dolphin activity budgets. Markov chain analysis revealed that in the presence of tour boats, dolphins were less likely to stay socializing and were more likely to begin traveling, and less likely to begin foraging while traveling. Additionally, activity budgets for foraging decreased and traveling increased as an effect of tour boat presence. These behavioral responses are likely to have energetic costs for individuals which may ultimately result in population-level impacts. Boat operator compliance with Panamanian whale watching regulations is urgently needed to minimize potential long-term impacts on this small, genetically distinct population and to ensure the future viability of the local tourism industry.
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Affiliation(s)
- Ayshah Kassamali-Fox
- Department of Environmental Studies, Antioch University New England, Keene, NH, USA.,Panacetacea, St. Paul, Minnesota, USA
| | - Fredrik Christiansen
- Aarhus Institute of Advanced Studies, Aarhus C, Denmark.,Department of Biology, Zoophysiology, Aarhus University, Aarhus C, Denmark
| | - Laura J May-Collado
- Department of Biology, University of Vermont, Burlington, VT, USA.,Centro de Investigación en Ciencias del Mar y Limnología, Universidad de Costa Rica, San José, Costa Rica.,Tupper Balboa Ancon, Smithsonian Tropical Research Institute, Panamá, Republic of Panamá
| | - Eric A Ramos
- Department of Psychology, The Graduate Center, City University of New York, New York, NY, USA.,Fundación Internacional para la Naturaleza y la Sostenibilidad, Quintana Roo, Mexico
| | - Beth A Kaplin
- Center of Excellence in Biodiversity and Natural Resource Management, University of Rwanda, Kigali, Rwanda.,School for the Environment, University of Massachusetts at Boston, Boston, MA, USA
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Fondren A, Swierk L, Putman BJ. Clothing color mediates lizard responses to humans in a tropical forest. Biotropica 2019. [DOI: 10.1111/btp.12744] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Affiliation(s)
- Andrea Fondren
- College of Agriculture and Sciences Iowa State University Ames IA USA
| | - Lindsey Swierk
- Department of Biological Sciences Binghamton University State University of New York Binghamton NY USA
| | - Breanna J. Putman
- Department of Ecology and Evolutionary Biology University of California Los Angeles CA USA
- Section of Herpetology and Urban Nature Research Center Natural History Museum of Los Angeles County Los Angeles CA USA
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Sanabria F, Daniels CW, Gupta T, Santos C. A computational formulation of the behavior systems account of the temporal organization of motivated behavior. Behav Processes 2019; 169:103952. [PMID: 31543283 PMCID: PMC6907728 DOI: 10.1016/j.beproc.2019.103952] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2019] [Revised: 08/30/2019] [Accepted: 08/31/2019] [Indexed: 02/02/2023]
Abstract
The behavior systems framework suggests that motivated behavior-e.g., seeking food and mates, avoiding predators-consists of sequences of actions organized within nested behavioral states. This framework has bridged behavioral ecology and experimental psychology, providing key insights into critical behavioral processes. In particular, the behavior systems framework entails a particular organization of behavior over time. The present paper examines whether such organization emerges from a generic Markov process, where the current behavioral state determines the probability distribution of subsequent behavioral states. This proposition is developed as a systematic examination of increasingly complex Markov models, seeking a computational formulation that balances adherence to the behavior systems approach, parsimony, and conformity to data. As a result of this exercise, a nonstationary partially hidden Markov model is selected as a computational formulation of the predatory subsystem. It is noted that the temporal distribution of discrete responses may further unveil the structure and parameters of the model but, without proper mathematical modeling, these discrete responses may be misleading. Opportunities for further elaboration of the proposed computational formulation are identified, including developments in its architecture, extensions to defensive and reproductive subsystems, and methodological refinements.
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Affiliation(s)
| | - Carter W Daniels
- Arizona State University, United States; Columbia University, United States
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Effects of whale-based tourism in Vava'u, Kingdom of Tonga: Behavioural responses of humpback whales to vessel and swimming tourism activities. PLoS One 2019; 14:e0219364. [PMID: 31276544 PMCID: PMC6611604 DOI: 10.1371/journal.pone.0219364] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Accepted: 06/21/2019] [Indexed: 12/04/2022] Open
Abstract
Vava’u, Kingdom of Tonga, is a well-established whale-watching destination in the South Pacific. Between July and October, the waters around the archipelago represent one of the most important breeding grounds for Oceania humpback whales (Megaptera novaeangliae). The Tongan government allows tourist swimming activities with whales and tour operators strongly promote the practice of swimming-with-whales, focusing primarily on mother-calf pairs. However, there is increasing evidence, derived from empirical research on swim-with-cetacean tourism, that this kind of interaction affects cetacean behaviour and can lead to negative effects on the cetaceans involved. This study represents the first assessment of humpback whales’ behavioural responses to vessel and swimmer approaches in Vava’u. Fifty-six surveys took place during the 2016 and 2017 whale breeding seasons aboard dedicated research and tour vessels. Whale dive time, number of reorientation events, and respiration rates were documented in both the absence and presence of boats and swimmers. Vessel approach type, swimmer placement, and whale avoidance responses were also recorded. Results indicate that the average diving time and the proportion of time spent diving in the presence of swimming activities increased significantly for mother-calf pairs (F2,36 = 18.183, P < 0.001; F2,36 = 5.462, P = 0.009, respectively). Moreover, avoidance responses of whales towards tour vessels were observed for one third of vessel approaches (33.5%) and the avoidance rate was significantly affected by the boat approach type (95% CI: 20.7–69.2%, z = 3.50, P < 0.001). Finally, low levels of compliance to the existing Tongan swim-with-whales regulations were documented, in particular the stipulated whale resting time between interactions with tour operator vessels and swimmers was often not respected (38.4%). Vava’u is an important calving ground for the Oceania humpback whale population and these findings should be carefully considered by stakeholders in Tonga and at other locations where swim-with-whales opportunities are being undertaken. Effective strategies to reduce the risk of detrimental effects on the whales targeted by swimming activities, especially mother-calf pairs, are needed.
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Sheehan RL, Papworth S. Human speech reduces pygmy marmoset (Cebuella pygmaea) feeding and resting at a Peruvian tourist site, with louder volumes decreasing visibility. Am J Primatol 2019; 81:e22967. [PMID: 30924189 DOI: 10.1002/ajp.22967] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2018] [Revised: 02/14/2019] [Accepted: 02/20/2019] [Indexed: 11/06/2022]
Abstract
Although potentially beneficial in terms of raising awareness and conservation funding, tourist visitation of wild primates can have negative impacts on visited groups. Tourism-generated noise is a relatively understudied facet of ecotourism research, and the effects of tourist-generated speech on free-ranging, wild primates has never been explored previously. This study investigates the behavioral responses of 10 groups of pygmy marmosets (Cebuella pygmaea) to human speech. Through the use of an experimental playback study using recorded human speech, we show that pygmy marmosets within the Tamshiyacu-Tahuayo Reserve, Peru, are significantly less visible, and often move completely out of sight after louder playbacks. Although no consistent differences were found in other behaviors with playback duration and volume, playbacks of human speech tended to increase the amount of time individuals were alert and decrease feeding and resting behaviors. Our results demonstrate that human speech can alter the behavior of visited primates, and identifies a decrease in primate visibility within the increasing volume. As all trials in this study took place near a marmoset group's feeding tree, moving out of sight from the visible study area is a particularly energetically costly behavior, and also has a negative effect on visitor enjoyment as it limits the time that they are able to view the target species. This response was not observed (nor was any other consistent behavior change) in control trials where the marmosets were exposed to human presence but not to speech, suggesting that negative tourist impacts can be reduced by encouraging tourists to refrain from speaking in the presence of visited primate groups.
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Affiliation(s)
- Rebecca L Sheehan
- School of Biological Sciences, Royal Holloway, University of London, Egham, Surrey, England
| | - Sarah Papworth
- School of Biological Sciences, Royal Holloway, University of London, Egham, Surrey, England
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Piwetz S. Common bottlenose dolphin (Tursiops truncatus) behavior in an active narrow seaport. PLoS One 2019; 14:e0211971. [PMID: 30779764 PMCID: PMC6380569 DOI: 10.1371/journal.pone.0211971] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2018] [Accepted: 01/24/2019] [Indexed: 11/18/2022] Open
Abstract
The Galveston Ship Channel (GSC) is a narrow, congested waterway that supports large-scale shipping, commercial fishing, dolphin tourism, and recreation. Human activity and common bottlenose dolphins (Tursiops truncatus) converge in the GSC with potentially negative consequences on the dolphins. Elevated land-based tracking and behavioral observation of dolphins and vessels were conducted along the GSC in June-August 2013 using a digital theodolite. Positional information was used to calculate dolphin movement patterns and proximity to vessels. Log-likelihood ratio and Chi-square contingency tests were used to assess behavioral states, and generalized additive models were used to analyze movement patterns (i.e., swimming speed, reorientation rate, and linearity) relative to endogenous and exogenous factors and vessel presence. Dolphins regularly use the GSC to forage (57% of observed behavioral states) and socialize (27%), and it is not a travel corridor for accessing other favorable sites (traveling = 5%). Dolphin behavior varied significantly based on time of day, group size, calf presence, and general boat presence. When boats were present, the proportion of time dolphins spent socializing and foraging was significantly less than expected by chance. Swimming speeds increased significantly in the presence of small recreational boats, dolphin-watching tour boats, shrimp trawlers, and when tour boats and shrimp trawlers were both present. Reorientation rate increased significantly in the presence of tour boats and trawlers. Dolphin behavioral responses to vessel presence may result in decreased energy consumption due to disrupted foraging activity. Without proper management, the observed behavioral changes may be detrimental to individuals within this population in the short term, with potential long-term consequences to health and survivorship.
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Affiliation(s)
- Sarah Piwetz
- Department of Marine Biology, Texas A&M University at Galveston, Galveston, Texas, United States of America
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Carder G, Plese T, Machado FC, Paterson S, Matthews N, McAnea L, D'Cruze N. The Impact of 'Selfie' Tourism on the Behaviour and Welfare of Brown-Throated Three-Toed Sloths. Animals (Basel) 2018; 8:ani8110216. [PMID: 30463203 PMCID: PMC6262464 DOI: 10.3390/ani8110216] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Revised: 11/03/2018] [Accepted: 11/05/2018] [Indexed: 11/24/2022] Open
Abstract
Simple Summary The use of wild animals as photo props is a potential animal welfare concern that is prevalent across Latin America. The present study documents animal welfare concerns associated with the use of wild caught brown-throated three-toed sloths (Bradypus variegatus) for wildlife ‘selfies’ by tourists at three locations in Manaus, Brazil and Puerto Alegria and Iquitos in Peru. Between 4 October 2016 and 8 April 2017 researchers attended 34 tours, where 17 sloths were observed. The sloths were; (1) held on average by 5 people (during each observation); (2) frequently exposed to physical manipulation of the head and/or limbs; and (3) frequently held by their claws. During handling the sloth’s behaviour was also analysed; we found that the two behaviours performed for the longest average duration of time were surveillance (55.3%) and limb stretching (12.6%). Further validation is needed; however, it is possible that some of the behaviours displayed may be indicators of fear, stress and anxiety. Our results describe behaviours exhibited by sloths, which have previously never been documented in any published literature, the data therefore serves as a potential baseline for future study. Abstract The use of wild animals as photo props is prevalent across the globe and is widely recognised to represent a potential animal welfare concern. However, detailed information regarding the specific impacts of such activity on wild animal behaviour is currently lacking. Herein, we investigated how brown-throated three-toed sloths (Bradypus variegatus) were handled by tourists, and how sloths behaved during wildlife ‘selfies’ taken in Manaus, Brazil and Puerto Alegria and Iquitos in Peru. In total, we observed 17 sloths (during 70 focal observations) that were provided for use in wildlife selfies on 34 different tours. We found that an average number of 5 people held each sloth during each focal observation. For 48.6% of the time the sloths were handled in a way which involved physical manipulation of the sloths’ head and/or limbs and/or being held by the claws. From the eight different types of sloth behaviour observed, we found that the two types performed for the longest average duration of time were surveillance (55.3%) and limb stretching (12.6%). Our findings show that when being handled sloths were frequently held in ways that may compromise their welfare. Although to date the behaviour of sloths while being handled has not been reported in any published literature, in this study we document certain behaviours which may act as indicators of compromised welfare. We suggest that our data provides a potential baseline for future study into the behaviour and welfare of sloths.
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Affiliation(s)
| | - Tinka Plese
- Aiunau Foundation, Circular 1ª, No. 73-20. Medellín, Colombia.
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Tyne JA, Christiansen F, Heenehan HL, Johnston DW, Bejder L. Chronic exposure of Hawaii Island spinner dolphins ( Stenella longirostris) to human activities. ROYAL SOCIETY OPEN SCIENCE 2018; 5:171506. [PMID: 30473795 PMCID: PMC6227997 DOI: 10.1098/rsos.171506] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Accepted: 09/24/2018] [Indexed: 06/09/2023]
Abstract
Habitat selection is strongly influenced by spatial variations in habitat quality and predation risk. Repeated exposure of wildlife to anthropogenic activities in important habitats may affect habitat selection, leading to negative biological consequences. We quantified the cumulative human exposure of a small, genetically isolated and behaviourally constrained spinner dolphin (Stenella longirostris) population, off Hawaii Island, and exposure effects on their daytime cumulative activity budget. Dolphins were exposed to human activities within 100 m for 82.7% of the daytime, with a median duration of 10 min between exposure events. Individual dolphins spent on average 61.7% (s.d. = 6.5) of their daytime resting. Of their total rest time, greater than 90% occurred inside sheltered bays. Despite high levels of human exposure, we did not observe an effect on dolphin resting behaviour. The short intervals between exposure events probably prevent dolphins from returning to a natural resting state before the next event. Consequently, 'control' observations may represent a resting behaviour of a more vigilant nature. Chronic levels of exposure to human activities could lead to rest deprivation, displacement from preferred resting habitats and ultimately negative population level effects. These results have implications for new proposed legislation aiming to reduce dolphin exposure to human activities.
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Affiliation(s)
- Julian A. Tyne
- Aquatic Megafauna Research Unit, School of Veterinary and Life Sciences, Murdoch University, 90 South Street, Murdoch, Western Australia, Australia
| | - Fredrik Christiansen
- Aquatic Megafauna Research Unit, School of Veterinary and Life Sciences, Murdoch University, 90 South Street, Murdoch, Western Australia, Australia
| | - Heather L. Heenehan
- Division of Marine Science and Conservation, Nicholas School of the Environment, Duke University Marine Lab, 135 Duke Marine Lab Road, Beaufort, NC, USA
| | - David W. Johnston
- Aquatic Megafauna Research Unit, School of Veterinary and Life Sciences, Murdoch University, 90 South Street, Murdoch, Western Australia, Australia
- Division of Marine Science and Conservation, Nicholas School of the Environment, Duke University Marine Lab, 135 Duke Marine Lab Road, Beaufort, NC, USA
| | - Lars Bejder
- Aquatic Megafauna Research Unit, School of Veterinary and Life Sciences, Murdoch University, 90 South Street, Murdoch, Western Australia, Australia
- Division of Marine Science and Conservation, Nicholas School of the Environment, Duke University Marine Lab, 135 Duke Marine Lab Road, Beaufort, NC, USA
- Marine Mammal Research Program, Hawaii Institute of Marine Biology, University of Hawaii, Hawaii, HI, USA
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Towards a Decommodified Wildlife Tourism: Why Market Environmentalism Is Not Enough for Conservation. SOCIETIES 2018. [DOI: 10.3390/soc8030059] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Wildlife tourism is frequently touted as a solution to the problems of increased poaching, habitat destruction, and species extinction. When wildlife is able to pay for its right to survive through attracting tourists, there is an incentive to conserve wildlife populations and the habitats that support them. However, numerous reports in recent years have drawn attention to the potential negative impacts of wildlife tourism attractions. This paper examines whether market environmentalism diminishes the potential of wildlife tourism to contribute to conservation and the welfare of individual animals. Market environmentalism commodifies the animals involved in wildlife tourism attractions and fuels an anthropocentric worldview where animals are resources to be used by humans for entertainment or economic gain, potentially presenting a threat to long-term conservation. Instead, we call for a decommodified experience of wildlife tourism based on more than just economic value.
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Fumagalli M, Cesario A, Costa M, Harraway J, Notarbartolo di Sciara G, Slooten E. Behavioural responses of spinner dolphins to human interactions. ROYAL SOCIETY OPEN SCIENCE 2018; 5:172044. [PMID: 29765660 PMCID: PMC5936925 DOI: 10.1098/rsos.172044] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Accepted: 03/20/2018] [Indexed: 05/10/2023]
Abstract
There is increasing evidence that whale and dolphin watching activities have detrimental effects on targeted cetacean populations. In Egypt, spinner dolphins regularly occur in the resting areas of Samadai, Satayah and Qubbat'Isa reefs. In-water human interactions with dolphins are regulated with a time-area closure system at Samadai, unregulated at Satayah and non-existent at Qubbat'Isa. This provided an ideal experimental setting to advance our understanding of the effects of tourism on a species highly sensitive to disturbances. Our study confirmed that the intensity and duration of interactions, and therefore, dolphin exposure to tourism, differed among the study sites. Compared with the Qubbat'Isa control site, behavioural reactions to boats and swimmers at the two tourism sites suggested that dolphin rest was disrupted, especially around the middle of the day and especially at Satayah, where dolphin tourism is unregulated. Our results indicate also that the dolphin protection measures at Samadai reduce the level of disturbance. We recommend that similar measures be implemented at other dolphin tourism locations, and that no new operations be initiated until the long-term impacts on dolphin populations are better understood. Our experience emphasizes the need to adopt precautionary approaches in research and management of whale and dolphin watching.
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Affiliation(s)
- Maddalena Fumagalli
- Department of Zoology, University of Otago, 340 Great King Street, Dunedin 9054, New Zealand
- Tethys Research Institute, Viale G.B. Gadio 2, Milano 20121, Italy
- Author for correspondence: Maddalena Fumagalli e-mail:
| | - Amina Cesario
- Tethys Research Institute, Viale G.B. Gadio 2, Milano 20121, Italy
- The Swire Institute of Marine Science, University of Hong Kong, Pokfulam Road, Hong Kong SAR, People's Republic of China
| | - Marina Costa
- Tethys Research Institute, Viale G.B. Gadio 2, Milano 20121, Italy
- South Atlantic Environmental Research Institute (SAERI), Stanley Cottage, Falkland Islands
| | - John Harraway
- Department of Mathematics and Statistics, University of Otago, 730 Cumberland Street, Dunedin 9016, New Zealand
| | | | - Elisabeth Slooten
- Department of Zoology, University of Otago, 340 Great King Street, Dunedin 9054, New Zealand
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Luo Q, Song Y, Hu X, Zhu S, Wang H, Ji H. Effects of tourism disturbance on habitat quality and population size of the Chinese giant salamander (Andrias davidianus). WILDLIFE RESEARCH 2018. [DOI: 10.1071/wr17092] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Context
Tourism is becoming one of the largest and fastest growing industries in many countries. Increasing tourism exerts serious impacts on the habitats of wildlife in nature reserves.
Aims
To ascertain how tourism affects the habitat of the Chinese giant salamander (Andrias davidianus), especially water quality and population size.
Method
An experiment was conducted to investigate the influences of different tourism disturbance intensities on the habitat quality and population size of the Chinese giant salamander in the Hunan Zhangjiajie Chinese Giant Salamander National Nature Reserve. Habitat characteristics, water physicochemical properties and microbial abundance were analysed, and population size estimated.
Key results
The results showed that high levels of tourism disturbance (>100 000 visitors per year) had negative effects on habitat quality. These effects included increased noise and abundance of aquatic microbes, increased concentration of total nitrogen (TN) and total phosphorus (TP) and a reduction of dissolved oxygen (DO) in water. The abundance of Escherichia coli could be regarded as an indicator of tourism disturbance on Chinese giant salamander.
Conclusions
It is concluded that: (1) the habitats were much noisier with increasing numbers of tourists, which might directly reduce the population size; (2) tourism indirectly disturbs the salamander population by increasing TN and TP, and reducing DO in the water; and (3) tourism might take in pathogenic microbes to the water habitats, which could cause disease for the salamander population.
Implications
Although tourism development might reduce local poverty, such efforts must consider the deterioration of habitats for wildlife, especially for this endangered animal species. Moreover, the intensity of tourism disturbance needs be reduced (by controlling the number of tourists) to achieve the coordinated development of tourism and wild animal protection.
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Seely E, Osborne RW, Koski K, Larson S. Soundwatch: Eighteen years of monitoring whale watch vessel activities in the Salish Sea. PLoS One 2017; 12:e0189764. [PMID: 29272275 PMCID: PMC5741222 DOI: 10.1371/journal.pone.0189764] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2017] [Accepted: 12/01/2017] [Indexed: 11/18/2022] Open
Abstract
The Soundwatch Boater Education Program is a vessel monitoring and public education outreach program. Soundwatch has been run by The Whale Museum (TWM) during the whale watch season (May through September) in the Haro Strait Region of the Central Salish Sea since 1993. Data collection has been in a consistent manner since 1998 and is presented here. The program compiles data on vessel types and vessel interactions with marine mammals with a focus on the Southern Resident killer whale (SRKW), Orcinas orca, which was listed as endangered under the U.S. Endangered Species Act (ESA) in 2005. The primary goal of the Soundwatch program is to reduce vessel disturbance to SRKWs and other marine wildlife through the education of boaters on regional, local and federal guidelines and regulations and the systematic monitoring of vessel activities around cetaceans. Since 1998, the number of active commercial whale watching vessels has increased over time; ranging from a low of 63 in 1999, to a high of 96 in 2015. In addition, the number of vessel incidents or violation of regulations and guidelines has also increased; ranging from a low of 398 in 1998 to a high of 2621 in 2012. Soundwatch collected data on 23 incident types, some remaining the same over the 18-year data set and some changing over time. The most common incidents over the 18 years were “Within 880 m of Lime Kiln” and “Crossing the path of whales”. The numbers of people kayaking near whales also significantly increased since 2004 with the incident “kayaks spread out” with a significantly increasing trend making it difficult for whales to avoid vessels. These results suggest a need for further outreach for effective education and enforcement of whale watching guidelines and regulations in the Central Salish Sea.
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Affiliation(s)
- Elizabeth Seely
- The Whale Museum, Friday Harbor, Washington, United States of America
- * E-mail:
| | - Richard W. Osborne
- University of Washington, Olympic Natural Resources Center, Forks, Washington, United States of America
| | - Kari Koski
- The Whale Museum, Friday Harbor, Washington, United States of America
| | - Shawn Larson
- The Whale Museum, Friday Harbor, Washington, United States of America
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D'Cruze N, Machado FC, Matthews N, Balaskas M, Carder G, Richardson V, Vieto R. A review of wildlife ecotourism in Manaus, Brazil. NATURE CONSERVATION 2017. [DOI: 10.3897/natureconservation.22.17369] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Bas AA, Christiansen F, Öztürk B, Öztürk AA, Erdog˘an MA, Watson LJ. Marine vessels alter the behaviour of bottlenose dolphins Tursiops truncatus in the Istanbul Strait, Turkey. ENDANGER SPECIES RES 2017. [DOI: 10.3354/esr00836] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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Filby NE, Christiansen F, Scarpaci C, Stockin KA. Effects of swim-with-dolphin tourism on the behaviour of a threatened species, the Burrunan dolphin Tursiops australis. ENDANGER SPECIES RES 2017. [DOI: 10.3354/esr00826] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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Akkaya Bas A, Christiansen F, Amaha Öztürk A, Öztürk B, McIntosh C. The effects of marine traffic on the behaviour of Black Sea harbour porpoises (Phocoena phocoena relicta) within the Istanbul Strait, Turkey. PLoS One 2017; 12:e0172970. [PMID: 28296899 PMCID: PMC5351841 DOI: 10.1371/journal.pone.0172970] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Accepted: 02/13/2017] [Indexed: 11/18/2022] Open
Abstract
Marine traffic is threatening cetaceans on a local and global scale. The Istanbul Strait is one of the busiest waterways, with up to 2,500 vessels present daily. This is the first study to assess the magnitude of short- and long-term behavioural changes of the endangered Black Sea harbour porpoises (Phocoena phocoena relicta) in the presence of marine vessels within the Istanbul Strait. Markov chains were used to investigate the effect of vessel presence on the transition probability between behavioural states (diving, surface-feeding and travelling), and to quantify the effect on the behavioural budget and bout length (duration of time spent in a given state) of porpoises. Further, the changes on swimming directions of porpoises in relation to vessel speed and distance was investigated using generalized linear models. In vessel presence, porpoises were less likely to remain in a given behavioural state and instead more likely to switch to another state. Because of this, the bout length of all three behavioural states decreased significantly in the presence of vessels. The vessel effect was sufficiently large to alter the behavioural budget, with surface-feeding decreasing significantly in the presence of vessels. However, when taking into account the proportion of time that porpoises were exposed to vessels (i.e. 50%), the measured effect size was not large enough to significantly alter the animals’ cumulative (diurnal) behavioural budget. Additionally, vessel speed and distance had a significant effect on the probability of porpoises showing a response in their swimming directions. The southern and middle sections of the Istanbul Strait, which have the heaviest marine traffic pressure, had the lowest porpoise sightings throughout the year. Conversely, northern sections that were exposed to a lesser degree of marine traffic hold the highest porpoise sightings. The effect shown in this study in combination with increasing human impacts within the northern sections should be considered carefully and species-specific conservation actions, including establishment of protected areas, should be put in place to prevent the long-term consequences of marine traffic on the Black Sea harbour porpoise population.
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Affiliation(s)
- Aylin Akkaya Bas
- Faculty of Fisheries, Istanbul University, Beyazit, Istanbul, Turkey.,Turkish Marine Research Foundation, Beykoz, Istanbul, Turkey.,Marine Mammals Research Association, Antalya, Turkey
| | - Fredrik Christiansen
- Cetacean Research Unit, School of Veterinary and Life Sciences, Murdoch University, Murdoch, Western Australia, 6150 Australia
| | - Ayaka Amaha Öztürk
- Faculty of Fisheries, Istanbul University, Beyazit, Istanbul, Turkey.,Turkish Marine Research Foundation, Beykoz, Istanbul, Turkey
| | - Bayram Öztürk
- Faculty of Fisheries, Istanbul University, Beyazit, Istanbul, Turkey.,Turkish Marine Research Foundation, Beykoz, Istanbul, Turkey
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Mason S, Salgado Kent C, Donnelly D, Weir J, Bilgmann K. Atypical residency of short-beaked common dolphins ( Delphinus delphis) to a shallow, urbanized embayment in south-eastern Australia. ROYAL SOCIETY OPEN SCIENCE 2016; 3:160478. [PMID: 27703709 PMCID: PMC5043329 DOI: 10.1098/rsos.160478] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Accepted: 08/26/2016] [Indexed: 06/06/2023]
Abstract
Short-beaked common dolphins (Delphinus delphis) are typically considered highly mobile, offshore delphinids. This study assessed the residency of a small community of short-beaked common dolphins in the shallow, urbanized Port Phillip Bay, south-eastern Australia. The ability to identify common dolphins by their dorsal fin markings and coloration using photo-identification was also investigated. Systematic and non-systematic boat surveys were undertaken between 2007 and 2014. Results showed that 13 adult common dolphins and their offspring inhabit Port Phillip Bay, of which 10 adults exhibit residency to the bay. The majority of these adults are reproductively active females, suggesting that female philopatry may occur in the community. Systematic surveys conducted between 2012 and 2014 revealed that the dolphins were found in a median water depth of 16 m and median distance of 2.2 km from the coast. The shallow, urbanized habitat of this resident common dolphin community is atypical for this species. As a result, these common dolphins face threats usually associated with inshore bottlenose dolphin communities. We suggest that the Port Phillip Bay common dolphin community is considered and managed separate to those outside the embayment and offshore to ensure the community's long-term viability and residency in the bay.
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Affiliation(s)
- Suzanne Mason
- The Dolphin Research Institute (DRI), PO Box 77, Hastings, Victoria 3915, Australia; Centre of Marine Science and Technology (CMST), Curtin University, GPO Box U1987, Perth, Western Australia 6845, Australia
| | - Chandra Salgado Kent
- Centre of Marine Science and Technology (CMST) , Curtin University , GPO Box U1987, Perth, Western Australia 6845 , Australia
| | - David Donnelly
- The Dolphin Research Institute (DRI) , PO Box 77, Hastings, Victoria 3915 , Australia
| | - Jeffrey Weir
- The Dolphin Research Institute (DRI) , PO Box 77, Hastings, Victoria 3915 , Australia
| | - Kerstin Bilgmann
- Department of Biological Sciences , Macquarie University , Sydney, New South Wales 2109 , Australia
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