Population abundance and habitat utilization of bottlenose dolphins in the Mississippi Sound

相似文献   

Fine‐scale population structure and connectivity of bottlenose dolphins,Tursiops truncatus,in European waters and implications for conservation

1. Protecting species often involves the designation of protected areas, wherein suitable management strategies are applied either at the taxon or ecosystem level. Special Areas of Conservation (SACs) have been created in European waters under the Habitats Directive to protect bottlenose dolphins, Tursiops truncatus, which forms two ecotypes, pelagic and coastal.
2. The SACs have been designated in coastal waters based on photo‐identification studies that have indicated that bottlenose dolphins have relatively high site fidelity. However, individuals can carry out long‐distance movements, which suggests potential for demographic connectivity between the SACs as well as with other areas.
3. Connectivity can be studied using genetic markers. Previous studies on the species in this area used different sets of genetic markers and therefore inference on the fine‐scale population structure and demographic connectivity has not yet been made at a large scale. A common set of microsatellite markers was used in this study to provide the first comprehensive estimate of genetic structure of bottlenose dolphins in European Atlantic waters.
4. As in previous studies, a high level of genetic differentiation was found between coastal and pelagic populations. Genetic structure was defined at an unprecedented fine‐scale level for coastal dolphins, leading to identification of five distinct coastal populations inhabiting the following areas: Shannon estuary, west coast of Ireland, English Channel, coastal Galicia, east coast of Scotland and Wales/west Scotland. Demographic connectivity was very low among most populations with <10% migration rate, suggesting no demographic coupling among them. Each local population should therefore be monitored separately.
5. The results of this study have the potential to be used to identify management units for bottlenose dolphins in this region and thus offer a significant contribution to the conservation of the species in European Atlantic waters. Future studies should prioritize obtaining biopsies from free‐living dolphins from areas where only samples from stranded animals were available, i.e. Wales, west Scotland and Galicia, in order to reduce uncertainty caused by sample origin doubt, as well as from areas not included in this study (e.g. Iroise Sea, France). Furthermore, future management strategies should include monitoring local population dynamics and could also consider other options, such as population viability analysis or the incorporation of genetic data with ecological data (e.g. stable isotope analysis) in the designation of management units.

     

Common bottlenose dolphin (Tursiops truncatus) abundance and distribution patterns in St Andrew Bay,Florida, USA

1. Common bottlenose dolphins (Tursiops truncatus) are found in temperate and tropical waters of the world across a wide range of habitats. Along Florida's north‐western coast, this species resides in the bays, sounds, and estuaries (BSE) and coastal (CST) waters of the northern Gulf of Mexico. The National Marine Fisheries Service has identified one CST (Northern Coastal Stock) and seven adjacent BSE dolphin stocks, including the St Andrew Bay BSE Stock.
2. Baseline data are critical to assess the impacts of ongoing and future anthropogenic stressors on these stocks. Currently, there is no comprehensive abundance estimate for the St Andrew Bay BSE Stock, and there are limited data on distribution patterns and site fidelity for this stock. In addition, little is known about the Northern Coastal Stock hypothesized to range from the Big Bend of Florida to the Mississippi River Delta, inclusive of the CST waters adjacent to St Andrew Bay.
3. The goals of this study were to conduct photographic‐identification surveys during 2015 and 2016 to determine abundance, distribution, and site fidelity of common bottlenose dolphins in the St Andrew Bay BSE Stock over four primary periods (July and October 2015, and April and October 2016).
4. St Andrew Bay BSE dolphin abundance was lowest in April 2016 (199, 95% confidence interval [CI] 173–246), followed by July 2015 (249, 95% CI 199–338), and highest in October 2015 (299, 95% CI 259–361) and October 2016 (315, 95% CI 274–378). Few individuals were sighted in both BSE and CST waters (N = 25/353; 7%), and this fact, taken in tandem with limited connections between the BSE and CST environments, suggests that there may be minimal overlap between the St Andrew Bay BSE and Northern Coastal Stocks.

     

Modelling dolphin distribution within an Important Marine Mammal Area in Greece to support spatial management planning

1. Understanding marine mammal distributions is essential for conservation, as it can help identify critical habitat where management action can be taken. The semi‐enclosed Gulf of Corinth, Greece, has been identified as an Important Marine Mammal Area by the International Union for Conservation of Nature (IUCN) Marine Mammal Protected Areas Task Force, based on the regular occurrence of odontocete populations. A 7‐year (2011–17) dataset of boat‐based surveys was used to model and predict the distribution of striped dolphins, Stenella coeruleoalba, common dolphins, Delphinus delphis, and common bottlenose dolphins, Tursiops truncatus, in the entire Gulf (2400 km²).
2. Multiple geographic, bathymetric, oceanographic, and anthropogenic variables were incorporated in a combined generalized additive model and generalized estimation equation (GAM‐GEE) framework to describe dolphin occurrence and produce distribution maps.
3. Modelling indicated that striped and common dolphins prefer deep waters (>300 m) in the central and southern part of the Gulf, whereas bottlenose dolphins prefer shallow waters (<300 m) and areas close to fish farms along the northern–central shore.
4. Model‐based maps of the predicted distribution identified a preferred habitat encompassing most of the Gulf, also revealing: (i) hot spots of dolphin distribution covering about 40% of the Gulf's surface; (ii) an almost complete overlap of striped and common dolphin distribution, consistent with the hypothesis that common dolphins modified their habitat preferences to live in mixed species groups with striped dolphins; (iii) a clear partitioning of striped/common and bottlenose dolphin habitat; and (iv) the important role played by fish farms for bottlenose dolphins, consistent with studies conducted elsewhere in Greece.
5. Evidence provided by this study calls for area‐specific and species‐specific management measures to mitigate anthropogenic impacts.

     

Responses of bottlenose dolphins (Tursiops spp.) to small drones

1. Recent advances in aerial drones offer new insights into the biology, ecology and behaviour of marine wildlife found on or near the ocean’s surface. While opening up new opportunities for enhanced wildlife monitoring, the impacts of drone sampling and how it might influence interpretations of animal behaviour are only just beginning to be understood.
2. The capacity of drones to record bottlenose dolphin (Tursiops spp.) behaviour was investigated, along with how the presence of a small drone at varying altitudes influences dolphin behaviour. Over 3 years and eight locations, 361 drone flights were completed between altitudes of 5 and 60 m above the ocean.
3. Analyses showed that dolphins were increasingly likely to change behaviour with decreasing drone altitude. A positive correlation was also found between time spent hovering above a group of dolphins and the probability of recording a behavioural response. Dolphin group size also influenced the frequency of an observed behavioural change, displaying a positive correlation between behaviour change and group size.
4. Overall, although drones have the potential to impact coastal dolphins when flown at low altitudes, they represent a useful tool for collecting ecological information on coastal dolphins owing to their convenience, low cost and capacity to observe behaviours underwater. To maximize benefits and minimize impacts, this study suggests that drones should be flown 30 m above coastal bottlenose dolphins.

     

Site‐fidelity and movement patterns of bottlenose dolphins (Tursiops truncatus) in central Argentina: essential information for effective conservation

1. The effectiveness of conservation measures such as marine protected areas (MPAs) for the conservation of cetaceans is determined by how well their home range or critical habitat is covered. The present study seeks to provide information on the site‐fidelity and movement patterns of individual bottlenose dolphins (Tursiops truncatus) in central Argentina.
2. Between 2007 and 2013, photo‐identification data of bottlenose dolphins were collected in four study sites some 90–200 km apart from each other along the central Argentinean coast.
3. Results show long‐term site‐fidelity (over 5 years) in one of the study areas. Re‐sighting rates further suggest the existence of different sub‐populations of bottlenose dolphins, but also confirm some connectivity (with movements over 200–290 km) and thus potential for gene flow within the region.
4. Considering the population declines of bottlenose dolphins in Argentina, information on site‐fidelity and movement patterns will be of value to improve the effectiveness of existing MPAs for the conservation of the species as well as prioritizing areas for increased research.

Copyright © 2016 John Wiley & Sons, Ltd.     

Challenges in monitoring mobile populations: Applying bayesian multi‐site mark–recapture abundance estimation to the monitoring of a highly mobile coastal population of bottlenose dolphins

1. Monitoring the abundance of mobile and wide‐ranging cetacean populations for conservation management is challenging, especially when the management is focused on static protected areas. Where abundance estimates are derived from mark–recapture data, such as photo‐identification of naturally marked individuals, unpredictable movements of animals in and out of the survey area can reduce ‘capture’ probabilities and affect the precision and accuracy of resulting estimates.
2. A Bayesian hierarchical log–linear model was applied to photo‐identification data collected in summer 2014 to derive a multi‐site abundance estimate for a population of bottlenose dolphins, Tursiops truncatus, ranging widely throughout the coastal waters of western Ireland. In addition, the effects of varying levels of sampling effort on the minimum detectable decrease in population size were examined.
3. The abundance (median) of dolphins was estimated as 189 (coefficient of variation (standard deviation/mean), 0.11; 95% highest‐posterior density interval, 162–232). Over 50% of the well‐marked dolphins encountered throughout the study were sighted in more than one distinct coastal area, thus displaying high mobility. In addition, it was found that it would require biennial surveys to detect a 25% decline in abundance within the six‐year reporting period of the EU’s Habitats Directive.
4. Given that the Special Area of Conservation designated for these dolphins consists of two separate areas covering a substantial portion of the west coast of Ireland, the multisite approach is appropriate for monitoring this population. It produces a more precise estimate and is well suited for sparse recapture data collected opportunistically at multiple sites, when the lack of resources prevents large‐scale surveys or when concentrating surveys on smaller localized areas fails to capture the broad range and unpredictable occurrence of the animals. The Bayesian multi‐site approach could be applied to the management of other wide‐ranging marine or terrestrial taxa.

     

Abundance estimates of three cetacean species in the coastal waters of Matang,Perak, Peninsular Malaysia

1. The paucity of baseline data on coastal cetaceans due to a lack of research in developing countries frequently precludes assessment of their status and informed management actions for conservation.
2. This study provides the first abundance estimates of Indo-Pacific humpback dolphins, Irrawaddy dolphins, and Indo-Pacific finless porpoises in the coastal waters of Matang, Peninsular Malaysia.
3. Boat-based surveys covering 1,152 km² of coastal waters with 4,108 km of survey effort were conducted between 2013 and 2016 to collect data for line transect analysis of Irrawaddy dolphins and finless porpoises. Photo-identification data of humpback dolphins were concurrently collected for mark–recapture analysis.
4. Estimates of abundance from four sampling strata totalled 763 Irrawaddy dolphins (CV = 13%, 95% confidence interval (CI) [588, 990]) and 600 Indo-Pacific finless porpoises (CV = 27%, 95% CI [354, 1,016]).
5. The annual abundance estimates of humpback dolphins ranged between 171 (95% CI [148, 208]) in 2014–2015 and 81 (95% CI [67, 98]) in 2015–2016, likely due to the presence of offshore individuals that moved in and out of the study area. The estuarine strata were inhabited by 68 (95% CI [63, 73]) inshore humpback dolphins in 2013–2014 to 87 (95% CI [78, 97]) dolphins in 2014–2015.
6. As an International Union for Conservation of Nature important marine mammal area, the productive coastal waters of Matang are shown to support a high density of small coastal cetaceans, and the results serve as an important baseline for future studies to identify population trends for conservation management plans.

     

Population genetic divergence of bonnethead sharks Sphyrna tiburo in the western North Atlantic: Implications for conservation

1. Sharks are a priority for conservation because numerous species, including small-sized coastal species, are being heavily exploited by commercial and recreational fisheries. Understanding the genetic population structure of sharks is key to effective management, maximizing their evolutionary potential in a rapidly changing environment and preventing population declines.
2. Limited dispersal is an important factor promoting population divergence for several coastal shark species. The genetic variation in 14 microsatellite loci and 21,006 single nucleotide polymorphisms genotyped using restriction-site-associated DNA sequencing was analysed to assess the genetic structure of the bonnethead shark, Sphyrna tiburo, in the western North Atlantic.
3. Genetic differences were identified among three well-defined regions: the western Florida coast, the south-eastern US Atlantic coast, and the southern Gulf of Mexico. Results support previous studies based on mitochondrial DNA sequences in defining differences among these regions and suggest limitations of bonnethead sharks in routinely performing long-distance migrations.
4. The limited connectivity among regions explains the pattern of genetic divergence but also reported divergence at the species/subspecies level. These genetically discrete bonnethead populations have independent evolutionary histories that may include local adaptations to specific areas.
5. Bonnethead sharks are currently managed as two stocks in the USA owing to recent genetic, tagging, and life history studies; however, no stock assessments or management plans exist for Mexico. These results not only serve to reinforce US management strategies and provide critical data about the extent of gene flow and sex dispersal among populations, but also begin the process of effective management in the waters of Mexico to ensure the long-term productivity and resilience of this species. With an absence of gene flow between populations from US waters and the southern Gulf of Mexico, there is a need for management plans based upon independent biological and population dynamics data since limited or no opportunities for populations to interchange individuals may occur to re-establish population viability.

     

Occurrence and present status of coastal dolphins (Delphinus delphis and Tursiops truncatus) in the eastern Ionian Sea

• 1. Boat surveys aimed at studying short‐beaked common dolphins and common bottlenose dolphins in eastern Ionian Sea coastal waters were conducted between 1993 and 2003. During 835 survey days, 24 771 km of total effort was distributed within an area of 480 km², resulting in 428 common dolphin and 235 bottlenose dolphin sightings.
• 2. Individual photo‐identification was performed extensively throughout this study, making it possible to monitor the number of animals seen in the study area each year and their long‐term residency patterns.
• 3. Common dolphins declined across the study period, from 2.18 encounters/100 km in 1997 to 0.40 encounters/100 km in 2003. In contrast, there was a relatively stable presence of bottlenose dolphins, some individuals showing high levels of site fidelity and others using the area only occasionally.
• 4. The local decline of common dolphins and the low density of bottlenose dolphins appeared to reflect the general status of these cetacean species in the wider Mediterranean region, where common dolphins were classified as endangered in the IUCN Red List in 2003.
• 5. Based on the available evidence, we infer that the present unfavourable status of common dolphins in eastern Ionian Sea coastal waters is largely a consequence of prey depletion.

Copyright © 2005 John Wiley & Sons, Ltd.     

Natural and anthropogenic drivers of foraging behaviour in bottlenose dolphins: Influence of shellfish aquaculture

1. In the coastal environment, marine mammals are exposed to one of the fastest growing food production sectors; namely, the shellfish farming industry. Identification of critical habitats, such as foraging grounds in highly human‐impacted areas, is essential to species conservation. Therefore, understanding the variables that influence a species' foraging behaviour is important for their conservation, especially for long‐lived mammals such as cetaceans.
2. The aims of this study were (a) to identify and quantify the environmental and anthropogenic drivers of wild bottlenose dolphin (Tursiops truncatus) foraging behaviour, and (b) to investigate whether the shellfish farming industry influences the behaviour of this species.
3. Behavioural observations were conducted along the north‐western coast of Spain, an area affected by intensive human activities, particularly the shellfish aquaculture industry.
4. A multi‐modelling approach highlighted the importance of shellfish farm areas as a foraging ground for bottlenose dolphins. Dolphins were predicted to be more likely found foraging inside shellfish farm areas than outside (57% vs. 43%).
5. Variability in bottlenose dolphin behaviour is likely a result of the interactions of environmental and anthropogenic drivers with prey availability and the physiological needs of the dolphins. Although shellfish farm areas provide high prey density for dolphins, they can also pose threats in a number of ways (i.e. collisions with vessels, entanglement with ropes, habitat loss, noise and water pollution).
6. From a conservation perspective, aquaculture management should consider the presence of dolphins foraging and minimize the associated risks that this industry may pose to these coastal cetaceans.

     

Survival rates for a declining population of bottlenose dolphins in Doubtful Sound,New Zealand: an information theoretic approach to assessing the role of human impacts

• 1. The bottlenose dolphins of Doubtful Sound, New Zealand are a declining population at the southern limit of the species' range, exposed to impacts from tourism and habitat modification. Patterns in apparent annual survival were analysed from photographic resightings of naturally marked adults (1990 to 2008) and calves within the first year of life (1994 to 2008) using capture‐recapture models.
• 2. The most parsimonious model for adults provided a time‐invariant, sex‐invariant estimate of survival (?_{a(1990–2008)}=0.9374; 95% CI: 0.9170–0.9530), marginally lower than prior estimates for wild bottlenose dolphins.
• 3. The most parsimonious model for calves indicated a significant time‐variant decline in survival from an estimate similar to other populations (?_{c(1994–2001)}=0.8621; 95% CI: 0.6851–0.9473) to a current estimate that is, to our knowledge, the lowest recorded for free‐ranging bottlenose dolphins (?_{c(2002–2008)}=0.3750; 95% CI: 0.2080–0.5782).
• 4. Information theoretic evidence ratios suggested that observed patterns in calf survival were 22 times more likely to be explained by a decline coincident with the opening of a second tailrace tunnel for a hydroelectric power station than by a decline in any other year or across multiple years.
• 5. Projections using an age‐structured stochastic population model indicated that the current level of calf survival was unsustainable (population decline: 100% of model runs; population extinction: 41.5% of model runs) and was a key factor in the observed population decline in Doubtful Sound.

Copyright © 2008 John Wiley & Sons, Ltd.     

Common dolphins,common in neritic waters off southern Israel,demonstrate uncommon dietary habits

1. During the last decade, the common dolphin (Delphinus delphis) has become the second most sighted species in Israeli coastal waters, after the common bottlenose dolphin. Documentation mostly relies on opportunistic, photo and/or video-backed second-party reports, delimited within a 10 km near-shore strip.
2. Sightings occur year round, are confined to the southern part of the Israeli coast and typically comprise relatively large groups (mean ± SD: 21.5 ± 13.3), often with young calves.
3. Strandings are relatively scarce, typically one per year, and have so far yielded five upper digestive tract contents for diet analysis.
4. Cephalopods comprised 1.2% of the estimated number of prey items in the combined content. Surprisingly, by far the most abundant and prevalent prey item found (57% of pooled prey items; present and dominant in four out of five tracts) was the Balearic eel (Ariosoma balearicum), a sand burrower which is also a major dietary component of the common bottlenose dolphins.
5. Bottlenose dolphins in Israel are known to forage in association with bottom trawlers, leading to the notion that common dolphins also make use of this foraging mode. Indeed, in addition to their association with purse seiners, they have been documented accompanying bottom trawlers, by both day and night. The slender Balearic eels are frequently found protruding from the net's eyes, presumably making easy prey for both dolphin species.
6. Information gaps on common dolphins include range extension to the south/south-west, abundance estimation and genetic flow/isolation. Even so, its unusual diet and the fact that the closest known populations to the north/north-west are from the Aegean Sea, were major considerations in the recent designation of the ‘Coastal Shelf Waters of the South-east Levantine Sea’ as a Mediterranean Important Marine Mammal Area.

     

Demography of southern Australian bottlenose dolphins living in a protected inverse estuary

1. Assessments of demographic parameters are essential to understand the dynamics of wild populations, and for their efficient conservation and management. Here, sex‐specific abundance, apparent survival and temporary emigration of southern Australian bottlenose dolphins (Tursiops cf. australis ) in Coffin Bay (CB), South Australia, is investigated.
2. Results are based on capture–recapture modelling of photo‐identification data and molecular analyses of biopsy samples collected during boat‐based surveys between September 2013 and October 2015 in the inner and outer areas of CB.
3. The total super‐population of dolphins (including calves) using the entire study area (263 km²) was estimated with POPAN models at 306 (95% CI: 291–323), which included 71 (68–73) marked females and 57 (55–60) marked males.
4. Seasonal estimates of abundance for the inner area of CB (123 km²) obtained with Pollock's Closed Robust Design models remained relatively constant over the two years (marked females: 52–60, marked males: 46–52, and total: 193–209).
5. The high density of dolphins inhabiting the inner area (seasonal range: 1.57–1.70 individuals km^?2), high apparent survival rates estimated for both sexes (females: 0.99; 95% CI: 0.96–1.0; males: 0.95; 0.82–0.99), and low temporary emigration rates (0.02; 95% CI: 0.01–0.11) indicate that the inner area of CB offers highly favourable habitat for these dolphins.
6. High biological productivity and low predation risk may promote these demographic patterns in the inner area of CB.
7. This study provides a robust baseline of sex‐specific population demographics of southern Australian bottlenose dolphins with important implications for future research and their management and conservation in South Australia.

     

Distribution and habitat characteristics of three sympatric cetacean species in the coastal waters of Matang,Perak, Peninsular Malaysia

1. Coastal cetaceans in Southeast Asia are poorly studied and are particularly vulnerable to anthropogenic threats, especially in intensive fishing grounds.
2. To investigate the distribution and habitat characteristics of cetaceans in the productive coastal waters of Matang, Perak, Malaysia, boat‐based line transect surveys were conducted between 2013 and 2016.
3. The Irrawaddy dolphin (Orcaella brevirostris) was most frequently encountered at 3.87 sightings per 100 km, followed by the Indo‐Pacific finless porpoise (Neophocaena phocaenoides) at 1.72 sightings per 100 km, and the Indo‐Pacific humpback dolphin (Sousa chinensis) at 0.66 sightings per 100 km.
4. The mean group size was largest for humpback dolphins (8.4 individuals), followed by Irrawaddy dolphins (6.4 individuals), and finless porpoises (2.8 individuals).
5. Humpback dolphins exhibited a clustered distribution concentrated mainly in shallow estuarine waters (<10 m deep and <5 km from river mouths), whereas Irrawaddy dolphins were more widely distributed in farther coastal waters (<15 m deep and <15 km from river mouths), and finless porpoises were mostly found farthest from the shore in coastal waters (10–25 m deep and >15 km from river mouths).
6. The spatial distribution of the three cetaceans overlapped minimally, and this is likely to reflect the distribution of preferred prey resources, species interactions, and their differential responses to anthropogenic activities and species dominance.
7. The results from our study serve as baseline information for future research, conservation, and habitat management of these vulnerable and endangered coastal cetaceans. Conservation actions are recommended for the Matang area.

     

Predictive spatial modelling of seasonal bottlenose dolphin (Tursiops truncatus) distributions in the Mississippi Sound

相似文献   

Habitat use of a coastal delphinid population investigated using passive acoustic monitoring

1. The population of bottlenose dolphins in eastern Scotland has undergone significant range expansion since the 1990s, when a Special Area of Conservation was established for the population.
2. Distribution of this population is well described within areas of its range where intensive work has been carried out, such as the inner Moray Firth, St Andrews Bay and the Tay estuary area. However, elsewhere in their range, habitat use is less well understood.
3. In this study, a large‐scale and long‐term passive acoustic array was used to gain a better understanding of bottlenose dolphin habitat use in eastern Scottish waters, complementing and augmenting existing visual surveys.
4. Data from the array were analysed using a three‐stage approach. First, acoustic occupancy results were reported; second, temporal trends were modelled; and third, a spatial–temporal‐habitat model of acoustic occupancy was created.
5. Results from the acoustic occupancy are in agreement with visual studies that found that areas near known foraging locations were consistently occupied. Results from the temporal trend analysis were inconclusive. Habitat modelling showed that, throughout their range, bottlenose dolphins are most likely to be detected closer to shore, and at a constant distance from shore, in deeper water.

     

Seasonal movements of immature Kemp's ridley sea turtles (Lepidochelys kempii) in the northern gulf of Mexico

1. Seasonal movements and core habitat areas of immature Kemp's ridley sea turtles (Lepidochelys kempii) in the northern Gulf of Mexico were tracked via satellite telemetry. Tagged turtles were incidentally captured by recreational fishermen and rehabilitated at the Institute for Marine Mammal Studies in Gulfport, Mississippi.
2. The average size of the core habitat areas (50% KDE (kernel density estimation)) was 1660.2 km² ± 3438.2 SD. Turtles displayed strong intra‐ and inter‐annual site fidelity to the Mississippi Sound during the spring, summer, and autumn months. During the winter months, most turtles, probably influenced by water temperatures, migrated to nearshore waters of Louisiana on either side of the Mississippi River Delta. However, other migration strategies were also observed.
3. Overall, these data indicate that the Mississippi Sound is an important developmental habitat for this critically endangered species. In addition, their wintering grounds in Louisiana are utilized by adult Kemp's ridleys and other sea turtle species as foraging grounds and migratory corridors. The high use of these areas by sea turtle populations increases the potential for negative impacts from anthropogenic disturbances (e.g. shrimp trawling, oil production, hypoxia) that occur there.

Copyright © 2016 John Wiley & Sons, Ltd.     

Distribution,abundance, and movements of the bottlenose dolphin (Tursiops truncatus) in the Pelagos Sanctuary MPA (north‐west Mediterranean Sea)

相似文献   

Using social media as a cost‐effective resource in the photo‐identification of a coastal bottlenose dolphin community

1. Bottlenose dolphins encountered around the Irish coast are considered part of a wide‐ranging coastal community; however, knowledge on the significance of the north of Ireland for this species is limited by a lack of dedicated effort.
2. Through social media, the opportunity now exists to gather large volumes of citizen science data in the form of high‐quality images, potentially extending the spatial and temporal scope of photo‐identification studies.
3. The purpose of this study was to investigate social media as a data resource for photo‐identification studies and to provide a preliminary assessment of bottlenose dolphins in the north of Ireland. Specifically, the study sought to examine the photo‐identification data for spatial clustering.
4. The study identified 54 well‐marked individuals and provided evidence of potential year‐round occurrence, with successful re‐sightings throughout the study period (2007–2016). There was a geographic concentration of re‐sightings along the north of Ireland, suggestive of interannual site fidelity. These results provide scientific rationale for strategically targeting the north of Ireland in future research on the Irish coastal community.
5. For effective conservation of the bottlenose dolphin it is imperative that scientific research, and resultant management objectives, consider wide‐ranging communities such as the Irish coastal community. Our research highlights data collection via social media as a cost‐effective and scientifically valuable tool in the photo‐identification of coastal cetaceans. We recommend that this method is used in research on low‐density and wide‐ranging coastal cetaceans.