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20 pages, 3 tables, 5 figures.-- Samantha Andrzejaczek ... et al.-- Distributed under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC), Knowledge of the three-dimensional movement patterns of elasmobranchs is vital to understand their ecological roles and exposure to anthropogenic pressures. To date, comparative studies among species at global scales have mostly focused on horizontal movements. Our study addresses the knowledge gap of vertical movements by compiling the first global synthesis of vertical habitat use by elasmobranchs from data obtained by deployment of 989 biotelemetry tags on 38 elasmobranch species. Elasmobranchs displayed high intra- and interspecific variability in vertical movement patterns. Substantial vertical overlap was observed for many epipelagic elasmobranchs, indicating an increased likelihood to display spatial overlap, biologically interact, and share similar risk to anthropogenic threats that vary on a vertical gradient. We highlight the critical next steps toward incorporating vertical movement into global management and monitoring strategies for elasmobranchs, emphasizing the need to address geographic and taxonomic biases in deployments and to concurrently consider both horizontal and vertical movements, Data analysis was funded by the Bertarelli Foundation through the Marine Science program through grants to D.J.C., B.A.B., and S.A. D.J.C. is also funded through Research England, UK. S.A. and B.A.B. thank the Moore Foundation and the Packard Foundation. F.G.-M. thanks the Instituto Politecnico Nacional for fellowships (COFAA, EDI). S.B.W. thanks funding from the Darwin Initiative (DPLUS046). A.D.M.D. acknowledges funding from the Research and Conservation Budget at Georgia Aquarium, including philanthropic gifts from several anonymous donors. K.F. acknowledges funding from the Rolex Awards for Enterprise and the Whitley Fund for Nature

Little is known about manta ray population size, structure, and connectivity in the Philippines. In collaboration with dive operators, non-governmental organizations, and authorities, sightings of manta rays were collated into a single national database. Using in-water photographs and videos gathered through citizen science and dedicated research efforts, this study compiled sightings between 2004 and 2020, showing 22 separate sites throughout the archipelago with manta rays present. A total of 392 individual reef manta rays (Mobula alfredi) and 107 oceanic manta rays (Mobula birostris) were identified from the collected footage. Four specific sites in the provinces of Masbate and Palawan together hosted 87% of all identified individuals and accounted for 94% of sightings, highlighting these areas are key aggregation sites. This study also reports movements of M. birostris within the Philippines, based on photo-identification of three individuals moving 150 km between Cebu and Masbate. Despite the growing number of recreational divers in Daanbantayan and San Jacinto, an 80% decline in M. birostris sightings was observed at these sites. To ensure effective future conservation, it is recommended that efforts focus on the identification and protection of manta ray hotspots and migratory corridors, the creation of a sustainable tourism framework, and most importantly, on the implementation of mitigation strategies to reduce fisheries interactions.

Marine traffic is increasing globally yet collisions with endangered megafauna such as whales, sea turtles, and planktivorous sharks go largely undetected or unreported. Collisions leading to mortality can have population-level consequences for endangered species. Hence, identifying simultaneous space use of megafauna and shipping throughout ranges may reveal as-yet-unknown spatial targets requiring conservation. However, global studies tracking megafauna and shipping occurrences are lacking. Here we combine satellite-tracked movements of the whale shark, Rhincodon typus, and vessel activity to show that 92% of sharks’ horizontal space use and nearly 50% of vertical space use overlap with persistent large vessel (>300 gross tons) traffic. Collision-risk estimates correlated with reported whale shark mortality from ship strikes, indicating higher mortality in areas with greatest overlap. Hotspots of potential collision risk were evident in all major oceans, predominantly from overlap with cargo and tanker vessels, and were concentrated in gulf regions, where dense traffic co-occurred with seasonal shark movements. Nearly a third of whale shark hotspots overlapped with the highest collision-risk areas, with the last known locations of tracked sharks coinciding with busier shipping routes more often than expected. Depth-recording tags provided evidence for sinking, likely dead, whale sharks, suggesting substantial “cryptic” lethal ship strikes are possible, which could explain why whale shark population declines continue despite international protection and low fishing-induced mortality. Mitigation measures to reduce ship-strike risk should be considered to conserve this species and other ocean giants that are likely experiencing similar impacts from growing global vessel traffic., [Significance] Global vessel traffic is increasing alongside world economic growth. The potential for rising lethal ship strikes on endangered species of marine megafauna, such as the plankton-feeding whale shark, remains poorly understood since areas of highest overlap are seldom determined across an entire species range. Here we show how satellite tracking whale sharks and large vessel movements globally provides a means to localize high-overlap areas and to determine how collision risk changes in time. Our results point to potential high levels of undetected or unreported ship strikes, which may explain why whale shark populations continue to decline despite protection and low fishing-induced mortality. Collision mitigations in high-collision-risk areas appear necessary to help conserve this iconic species., Funding for data analysis was provided by the UK Natural Environment Research Council (NERC) through a University of Southampton INSPIRE DTP PhD Studentship to F.C.W. Additional funding for data analysis was provided by NERC Discovery Science (NE/R00997/X/1) and the European Research Council (ERC-AdG-2019 883583 OCEAN DEOXYFISH) to D.W.S., Fundação para a Ciência e a Tecnologia (FCT) under PTDC/BIA/28855/2017 and COMPETE POCI-01–0145-FEDER-028855, and MARINFO–NORTE-01–0145-FEDER-000031 (funded by Norte Portugal Regional Operational Program [NORTE2020] under the PORTUGAL 2020 Partnership Agreement, through the European Regional Development Fund–ERDF) to N.Q. FCT also supported N.Q. (CEECIND/02857/2018) and M.V. (PTDC/BIA-COM/28855/2017). D.W.S. was supported by a Marine Biological Association Senior Research Fellowship.

Wildlife tourism can act as an incentive for the conservation of marine species and habitats. One of the most important outcomes can be a change in the views of participants towards target species and their habitats that may promote more conservation-oriented actions. While a handful of studies have documented the wildlife value orientations (WVOs) of tourists participating in marine wildlife tourism, no studies have explored the WVOs of locals working in tourism. However, it is equally important to understand the WVOs of locals working in community-based tourism, and whether these are linked with changes in locals' attitudes and behaviors towards marine wildlife and the ocean. This article assesses the WVOs of locals working in community-based whale shark tourism at four sites in the Philippines, and explores the relationship between WVOs and conservation attitudes and behaviors using a mixed methods approach with a total of 114 structured interviews. Three WVO groups were identified (mixed utilitarian–protectionist, moderate protectionist, and high protectionist), suggesting a WVO continuum. Those respondents with more protectionist views reported more conservation outcomes, including changes in attitudes and behaviors to protect whale sharks. Further, respondents who worked in tourism had more protectionist views than those from a failed tourism site, indicating that tourism can change communities by helping locals value their marine resources and incentivizing protection of those resources.

Whale shark (Rhincodon typus) tourism is increasingly popular at predictable aggregations around the world, but only a few use provisioning to ensure close interactions. Understanding the effects of provisioning on the behaviour of this endangered species is critical to manage this growing industry. We recorded the diving behaviour and habitat use of juvenile whale sharks (n = 4) for a mean of 49.5 provisioned and 33.8 non-provisioned days using temperature-depth-recorders. We found that time spent at the surface (10 values for ectotherms, we estimate a 7.2 ± 3.7% (range 1.3–17.8%) higher metabolic rate when sharks frequent the provisioning site. The observed behavioural, habitat use, and potential fitness shifts should be considered when developing guidelines for sustainable tourism, particularly in light of new provisioning sites developing elsewhere.

Cleaning interactions are essential for healthy marine ecosystem communities. This study reports the first documentation of the whale shark Rhincodon typus cleaning behaviour in the Indo-West Pacific by two wrasse species, the blue-streak cleaner wrasse Labroides dimidiatus and the moon wrasse Thalassoma lunare in Cebu, Philippines. This study documented 36 cleaning interactions with 14 individual whale sharks. The cleaning interactions appear opportunistic rather than targeted by the sharks, unlike that observed in other species of elasmobranchs. Further work should focus on understanding the drivers of these unique cleaning interactions.

A basic tenet of ecotourism is to enhance conservation. However, few studies have assessed its effectiveness in meeting conservation goals and whether the type of tourism activity affects outcomes. This study examines whether working in ecotourism changes the perceptions of and attitudes and behaviours of local people towards the focal species and its habitat and, if so, if tourism type affects those outcomes. We interviewed 114 respondents at four whale shark Rhincodon typus tourism sites in the Philippines to compare changes in perceptions of and attitudes and behaviours towards whale sharks and the wider marine environment. We found that the smaller scale tourism sites had greater social conservation outcomes than the mass or failed tourism sites, including changes in conservation ethics and perceptions of and attitudes and behaviours towards whale sharks and the ocean. Furthermore, of the three active tourism sites, the smallest site, with the lowest economic returns and the highest negative impacts on whale sharks prior to tourism activities, had the largest proportion of respondents who reported a positive change in perceptions of and attitudes and behaviours towards whale sharks and the ocean. Our results suggest that tourism type, and the associated incentives, can have a significant effect on conservation outcomes and ultimately on the ecological status of an Endangered species and its habitat.

Perceived crowding is an important measure in assessing the social impacts of tourism activities. The goal of this study was to determine if the method used to measure perceived crowding in the marine environment (numerical vs. visual approach, boat vs. swimmer crowding) affects the crowding outcome and to apply the concept to a high-density marine wildlife tourism site, viewing whale sharks in Oslob, Philippines. The influence of various variables, including specialization, gender, nationality, swimmer behaviors, and proximity, was also tested to see if they affected crowding levels. Results indicate that a visual approach is more accurate in measuring reported encounters and encounter norms, and that boat and swimmer crowding are not interchangeable. Boat crowding is a serious problem in Oslob (95.6% crowded). Specialization, nationality, and swimmer behaviors and proximity all affected perceived crowding. Individuals who reported feeling crowded were more likely to perceive negative impacts of tourism activities on the local community, whale sharks, and wider environment. They also showed higher levels of support for management interventions to limit the number of people and boats at the site and to better regulate or ban whale shark provisioning activities. This study provides important insights regarding how to measure perceived crowding in the marine environment and management implications for a mass tourism wildlife site experiencing overcrowding.

The green turtle Chelonia mydas is an Endangered species that forms aggregations at neritic foraging sites where juveniles spend, in some cases, over a decade before moving to adult- or subadult-dominated foraging sites. Here, we used photographic identification, behavioural observations, paired-laser and stereo-photogrammetry to determine the population dynamics of a coastal aggregation of green turtles in Oslob, Philippines. We identified a total of 82 individual turtles between May 2012 and October 2018. We recorded behavioural observations during individual identification and found that turtles changed behaviour in 25% of instances. Some turtles were identified consistently throughout the study period, indicating strong site fidelity and residency. Modified maximum likelihood models suggest turtles spend the majority of their time within the study area (>92%), although some (8%) excursions outside the area do occur. Mark-recapture models suggest this foraging aggregation exhibits a pattern similar to that of a closed population. This is likely due to the extended residency periods of some individuals at the site, and the relatively low recruitment rate over time. We measured 18 turtles using paired-laser photogrammetry, with estimated straight carapace length of 55.3 cm, and mean growth rates of 3.4 cm yr-1. Stereo-photogrammetry measurements were consistent and more accurate than visual or paired-laser photogrammetry estimates. Our results highlight the use of in-water methods to understand population dynamics of green turtles, and the importance of coastal, juvenile-dominated habitats for green turtles, as well as the need for effective conservation and management strategies to safeguard them.

The Philippines is home to the second largest known population of whale sharks in the world. The species is listed as endangered due to continued population declines in the Indo-Pacific. Knowledge about the connectivity within Southeast Asia remains poor, and thus international management is difficult. Here, we employed pop-up archival tags, data mining and dedicated effort to understand an aggregation of whale sharks at Honda Bay, Palawan, Philippines, and its role in the species' conservation. Between Apr and Oct 2018, we conducted 159 surveys identifying 117 individual whale sharks through their unique spot patterns (96.5% male, mean 4.5 m). A further 66 individual whale sharks were identified from local operators, and data mined on social media platforms. The satellite telemetry data showed that the whale sharks moved broadly, with one individual moving to Sabah, Malaysia, before returning to the site

Ziegler et al. (2018) assessed tourists’ perceptions of the ethics of feeding an endangered species for tourism purposes. The ethical decisions made, and justifications provided, were assessed using utilitarian and animal welfare ethical philosophies. We concluded that despite the substantial social and economic benefits of this activity, it remains unclear whether these benefits outweigh the potential costs to the whale sharks, the community, and the greater environment. There is no evidence that provisioning is not detrimental to the sharks. Consequently, we invoke the precautionary principle whereby the onus to prove no detrimental impact should be on the proponents of provisioning whale sharks. Due to the lack of published, peer-reviewed “robust and unequivocal” scientific evidence of the impacts of this activity alluded to by Meekan and Lowe, our conclusions stand until thorough cost-benefit analyses are completed.

Elasmobranchs are experiencing population declines worldwide because of anthropogenic stressors. Marine protected areas (MPAs) have been shown to benefit mesopredatory species of shark. The Tubbataha Reefs Natural Park (TRNP) is a United Nations Educational, Scientific and Cultural Organization World Heritage Site and the largest no-take MPA in the Philippines, yet information on the current status of elasmobranchs in the park is limited. Here, we investigate the abundance and biodiversity of elasmobranchs in TRNP using underwater visual census (UVC) and baited remote underwater video (BRUV) surveys. Twenty UVC were conducted in May 2015 (n = 10) and June 2016 (n = 10), documenting eight species of elasmobranchs with an average density of 7.18 sharks ha-1 for both years. A total of 113 successful BRUV surveys were conducted in TRNP between March–June 2015 (n = 47) and April–June 2016 (n = 66). The BRUV surveys recorded 14 species with an average catch per unit effort of 2.09 elasmobranchs per hour for both years. Both survey methods report some of the highest densities of the grey reef shark Carcharhinus amblyrhynchos and the whitetip reef shark Triaenodon obesus documented worldwide. This study underlines the importance of large, well-managed MPAs such as TRNP for the conservation of reef-associated elasmobranchs. Keywords: Baited remote underwater video, Elasmobranch conservation, Marine protected area, Reef sharks, Southeast Asia

This study explored the ethics of provisioning wildlife to enhance tourist interactions at a whale shark tourism site in Oslob, Philippines. TripAdvisor comments (n = 947) and tourist surveys (n = 761) were used to better understand tourists' perceptions of whale shark provisioning in Oslob. The ethical decisions made were then critically assessed using utilitarian and animal welfare ethical philosophies. The majority of respondents supported whale shark provisioning, despite many being aware of the ethical complications of provisioning sharks for tourism purposes. Respondents justified their participation in this activity using mainly economic, human enjoyment, and animal welfare arguments. A utilitarian assessment of the potential costs and benefits of this activity highlighted the gaps in our knowledge regarding the economic and social benefits of this activity, as well as the negative impacts on the sharks’ welfare. Until such analyses are completed, significant ethical questions remain regarding the provisioning of these sharks.

The whale shark is the world's largest fish that forms predictable aggregations across its range, many of which support tourism industries. The largest non-captive provisioned whale shark destination globally is at Oslob, Philippines, where more than 500 000 tourists visit yearly. There, the sharks are provisioned daily, year-round, allowing the human–shark interaction in nearshore waters. We used in-water behavioural observations of whale sharks between 2015 and 2017 to understand the relationship between external stimuli and shark behaviour, whether frequency of visits at the site can act as a predictor of behaviour, and the tourist compliance to the code of conduct. Mixed effects models revealed that the number of previous visits at the site was a strong predictor of whale shark behaviour, and that provisioned sharks were less likely to exhibit avoidance. Compliance was poor, with 93% of surveys having people less than 2 m from the animal, highlighting overcrowding of whale sharks at Oslob. Given the behavioural implications to whale sharks highlighted here and the local community's reliance on the tourism industry, it is imperative to improve management strategies to increase tourist compliance and strive for sustainable tourism practices.

Cleaning interactions are essential for healthy marine ecosystem communities. This study reports the first documentation of the whale shark Rhincodon typus cleaning behaviour in the Indo-West Pacific by two wrasse species, the blue-streak cleaner wrasse Labroides dimidiatus and the moon wrasse Thalassoma lunare in Cebu, Philippines. This study documented 36 cleaning interactions with 14 individual whale sharks. The cleaning interactions appear opportunistic rather than targeted by the sharks, unlike that observed in other species of elasmobranchs. Further work should focus on understanding the drivers of these unique cleaning interactions.

Citizen science by which the general public is enlisted to participate in data collection programmes, can shed light on the biology and ecology of enigmatic species. The whale shark Rhincodon typus, the world’s largest fish, is listed as Endangered in the IUCN Red List of Threatened Species due to continued population declines, particularly in the Indo-Pacific region. The species is highly mobile, capable of crossing international boundaries, yet the species’ movements in Southeast Asia remain poorly understood. Citizen science has been used broadly in the region and beyond, to understand the species’ biology and ecology. Here, we report the first international movement of a whale shark between the Philippines and Malaysia as determined through photo-ID and citizen science. A juvenile female whale shark, P-1159, was first identified in Oslob, Cebu, Philippines in December 2017 by ongoing research at the site, and resighted in Pulau Sipadan, Sabah, Malaysia, in October 2019 by a citizen scientist. Pulau Sipadan is one of Southeast Asia’s most popular diving destinations, yet whale shark sightings are uncommon. Citizen scientists ready to collect and share data with ongoing research plays a key role in monitoring enigmatic species. Protocols should be developed to systematically collect unique sightings and behaviours accessible to divers as citizen scientists that would otherwise be lost to science.

Shark-based tourism is a rapidly growing industry, particularly with whale sharks, as new hotspots are identified worldwide. Understanding any impacts of tourism is essential to minimize any potential detrimental effects on the target species and habitat. In-water behavioural observations of whale sharks were used to understand any impacts of tourism at a small site in Panaon Island, Southern Leyte, Philippines. A generalized linear mixed model was fitted to test anthropogenic and environmental variables, with interaction duration as the response variable, to assess any disturbance to the animals by the tourism activities. Whale sharks were observed between the months of November and June between 2013 and 2016, with highly variable seasons. In total, 527 tourist-whale shark interactions were recorded during 359 trips identifying 104 individual whale sharks, most of which were juvenile males (85%, measuring c. 5.5 m total length). Proximity of motorized vessels and interactions in deeper waters were found to significantly shorten interactions. Short-term behavioural changes were observed in response to human events (e.g. touching). Interactions when whale sharks were feeding were significantly longer than when they were not. Individual behavioural variability was observed. Impacts could be mitigated with small managerial changes and increased enforcement, such as limiting the number of motorized vessels and the number of people around the whale sharks. Although no long-term impacts were recorded during this study, it is difficult to ascertain this in a long-lived, wide-ranging species. This knowledge gap highlights the need to build long-term monitoring programmes, and to apply the precautionary principle for the sustainable use of this endangered species.

We report the occurrence of the reef manta ray Manta alfredi Krefft 1868 in the Bohol Sea, Philippines, based on photographic evidence from boat-based surveys and a fishery specimen. Despite previous anecdotal reports from the diving industry and over a century of extensive targeted fisheries for mobulid rays in the Philippines, it was not until recently that the species was first confirmed in the country at the Tubbataha Reefs Natural Park, Palawan. Our results confirm the presence of M. alfredi in the Visayas region of the Philippines, extending the current range for the species from the Sulu Sea over 600 km eastwards. Its presence in a region with an active mobulid fishery has important implications for the conservation and management of M. alfredi in the country. We highlight the need to understand the distribution of M. alfredi in the region and make management recommendations based on the present study.

Determining the life history and population parameters of sea turtles typically involves the live capture of animals. Photo-identification (photo-ID) of free-ranging individuals is a cost-effective alternative to conventional tagging for mark-recapture studies that also minimises the risk of injury or stress to the animals. Paired laser-photogrammetry (photogrammetry) is a minimally invasive technique to size animals and has been proven effective in a range of different taxa. Photo-ID and photogrammetry were combined as minimally invasive techniques to determine life-history parameters of free-ranging green sea turtles Chelonia mydas at a site in Oslob, Cebu, Philippines. The pattern-recognition software I 3 S Pattern was used to validate results and confirm visual matching. A total of 38 individuals were identified at the site through photo-ID. Facial scutes remained unchanged for a min. of 3.6 years. Photogrammetry was employed to measure straight carapace lengths (SCLs) of a sample of 17 individuals, with a mean straight carapace length of 52.5 ± SD 1.1 cm. Modified maximum likelihood methods were used to model mean residency of 873 d at the site, with c . 12 individuals present at any one time. Based on photogrammetry measurements, individuals at the site were found to be of immature age class. This, along with the extended residency times, indicates that the site could be an important developmental habitat. Photo-ID is a valid minimally invasive technique for identifying individual C. mydas for mark-recapture analyses. The use of paired laser photogrammetry for categorising the life-history stage of an aggregation of sea turtles is demonstrated for the first time. Identification of such developmental habitats through the employment of these minimally invasive techniques is useful for conservation of the species.

This study explored the ethics of provisioning wildlife to enhance tourist interactions at a whale shark tourism site in Oslob, Philippines. TripAdvisor comments (n=947) and tourist surveys (n=761) were used to better understand tourists’ perceptions of whale shark provisioning in Oslob. The ethical decisions made were then critically assessed using utilitarian and animal welfare ethical philosophies. The majority of respondents supported whale shark provisioning, despite many being aware of the ethical complications of provisioning sharks for tourism purposes. Respondents justified their participation in this activity using mainly economic, human enjoyment, and animal welfare arguments. A utilitarian assessment of the potential costs and benefits of this activity highlighted the gaps in our knowledge regarding the economic and social benefits of this activity, as well as the negative impacts on the sharks’ welfare. Until such analyses are completed, significant ethical questions remain regarding the provisioning of these sharks.

The whale shark, Rhincodon typus, is a charismatic umbrella species whose highly mobile nature is not yet fully understood. Whale sharks roam the Philippine archipelago with two major aggregations known to occur at Donsol and at a provisioning site in Cebu. This is the first description of a previously identified aggregation occurring off Panaon Island, Southern Leyte through the use of photographic identification. In total, 93 individual whale sharks were identified, with significant male bias (58%). The mean estimated total length of individuals was 5.72 ± 1.02 m S.D., indicating a juvenile aggregation. Partial or complete fin amputations, potentially resulting from fishing lines, boat propellers or net entanglement, were observed on 27% of animals, highlighting some of the risks human activities can have on this threatened species. Multiple parallel scars, identified as propeller impact, were observed on 45% of animals. Dedicated research seasons in 2013 and 2014 yielded very different whale shark encounters with 366 in 2013 and 12 in 2014, yet highlighted the recurrence of individuals at the study site. Complemented by data collected through citizen science, maximum likelihood methods were used to model mean residency of whale sharks at Panaon Island of 27.04 days. The modelled lagged identification rate showed that many whale sharks return to the study site over time. Whale sharks from Panaon Island were identified through photo-ID and citizen science at other sites in the Philippines, as well as a match to Taiwan, representing the first international match through photo-ID in South-east Asia with a minimum distance covered of 1600 km. Given the highly mobile nature and recent exploitation of this species, management is recommended as a single unit regionally in South-east Asia. Additional research is needed to focus on the drivers of variation in encounters at whale shark aggregation sites. Copyright © 2016 John Wiley & Sons, Ltd.

Donsol in the Philippines is the longest running community-based whale shark (Rhincodon typus) ecotourism site in Southeast Asia, with peak visitation in 2012 of over 27,000 tourists. In order to understand this aggregation and the importance of the area to whale sharks, dedicated photographic identification (photo-ID) research began in 2007. In-water photo-ID surveys were conducted from tourism boats, weather and operator permitting, from December to June between 2007 and 2016. Visual matches of the unique spot patterns of each individual shark were validated by the pattern-recognition software Interactive Individual Identification System (I3S), and on the online database Wildbook for Whale Sharks (www.whaleshark.org). A total of 1,985 photo-ID trips over 895 survey days resulted in 6,786 encounters with R. typus. Combined with encounters from both dedicated research and citizen science dating back to 1998, 479 individual whale sharks were identified, making up 44% of the known whale shark population in the Philippines (n = 1,095). Of these, photographs of the pelvic region confirmed the sex for 158 males and 22 females. Visual size estimates ranged from 2 to 10 m (mean ± S.D = 6.5 ±1.6 m). Maturity in males (LT50) was estimated at 6.8 ± 0.2 m total length, with 53% of males considered mature. Annually, the total number of individuals sighted varied between 15 and 185 ( mean ± S.D = 104 ± 55.53), with a recruitment of 3-90 new individuals yearly (mean ± S.D = 46.8 ± 36.29). Modelled residency using maximum likelihood methods suggested whale sharks spent 49.8 ± S.E. 14.5 (95% CI [32.3 – 78.6]) days in Donsol each season, with 47.1 – 60.8 whale sharks at any one time during the season. Twenty individuals were recorded through photo-ID at other sites across the Philippines. The extended residency of whale sharks at Donsol, paired with the presence of sexually mature animals and the economic value of the tourism industry, highlights the importance of Donsol for this endangered species.

In light of the global decline of mobulid populations and the necessity for sustainable fisheries management, baseline data for population dynamics were collected from a targeted fishery in the Bohol Sea, Philippines. This study focused on life-history parameters and reproductive cycles of four mobulid rays (Mobula thurstoni, Mobula japanica, Mobula tarapacana, and Manta birostris), and re-estimated their intrinsic population growth rates. Size and reproductive data were collected from 1,509 specimens (30% of catch) landed in two fishing seasons in 2015 and 2016. Size-at-birth was reviewed, and analysis of the embryos and follicles did not show any clear seasonality in the reproductive cycle, but supported an interbreeding interval. Females of all species matured at a larger size than males, and exhibited a larger size-at-pregnancy than -at-maturity. This delay in reproduction resulted in population growth rates lower than the actual rmax when based on size-at-pregnancy (rmat = rmax = 0.016–0.055 year−1 and rpreg = 0.008–0.044 year−1), and a population doubling time of 15.8–86.6 years. This study suggests that population growth rates previously reported were overestimated. In light of the Convention on International Trades of Endangered Species (CITES) and Convention on Migratory Species (CMS) assessments, while fisheries management should reflect the delayed maturation of these species and the slower population growth potential, at the current status of these population, the sustainability of any exploitation level seems unrealistic and strongly discouraged.

The whale shark Rhincodon typus was uplisted to ‘Endangered’ in the 2016 IUCN Red List due to >50% population decline, largely caused by continued exploitation in the Indo-Pacific. Though the Philippines protected the whale shark in 1998, concerns remain due to continued take in regional waters. In light of this, understanding the movements of whale sharks in the Philippines, one of the most important hotspots for the species, is vital. We tagged 17 juvenile whale sharks with towed SPOT5 tags from three general areas in the Sulu and Bohol Seas: Panaon Island in Southern Leyte, northern Mindanao, and Tubbataha Reefs Natural Park (TRNP). The sharks all remained in Philippine waters for the duration of tracking (6–126 days, mean 64). Individuals travelled 86–2,580 km (mean 887 km) at a mean horizontal speed of 15.5 ± 13.0 SD km day−1. Whale sharks tagged in Panaon Island and Mindanao remained close to shore but still spent significant time off the shelf (>200 m). Sharks tagged at TRNP spent most of their time offshore in the Sulu Sea. Three of twelve whale sharks tagged in the Bohol Sea moved through to the Sulu Sea, whilst two others moved east through the Surigao Strait to the eastern coast of Leyte. One individual tagged at TRNP moved to northern Palawan, and subsequently to the eastern coast of Mindanao in the Pacific Ocean. Based on inferred relationships with temperature histograms, whale sharks performed most deep dives (>200 m) during the night, in contrast to results from whale sharks elsewhere. While all sharks stayed in national waters, our results highlight the high mobility of juvenile whale sharks and demonstrate their connectivity across the Sulu and Bohol Seas, highlighting the importance of the area for this endangered species.

Background Shark viewing tourism is a burgeoning global industry. Numerous operations provision sharks to increase sightings yet the effects of provisioning on shark behaviour are often poorly understood. At a unique provisioning site in Oslob, Cebu, Philippines, whale sharks (Rhincodon typus) have become the focus of a mass tourism operation since late 2011, receiving over 185,000 tourists a year. Approach To better understand and advise management bodies on the effects of provisioning on these animals, we used photographic identification (photo-ID) to assess the daily abundance and site visitation patterns of the sharks. Principal coordinate analysis (PCoA) based on co-occurrence matrices was used to investigate visitation patterns amongst individuals and define groupings. Modified maximum likelihood methods were then used to model mean residency for these different groups. Results Between March 31st 2012 and March 31st 2015, we identified 209 (165 males, 34 females and 10 of unknown sex) individuals at the site (a 0.065 km2 demarked area located 50 – 100 m from shore), with an average of 12.4 (SD = ± 4.8, range = 2 – 31) sharks sighted per day. Daily shark abundance increased over time and showed strong seasonal variation, with annual peaks occurring between May and November. We documented a spectrum of site visitation patterns ranging from single sighting (21% of sharks identified) to year-round residency (5% of sharks identified). For frequently sighted sharks, PCoA revealed two primary residency groupings: highly resident sharks (N = 9), which were seen year-round with few prolonged absences, and seasonal sharks (N = 21), which were primarily present between May and November. The daily abundance of highly resident sharks varied nonlinearly over time with no clear trend, while the daily abundance of seasonal sharks showed a clear increase during peak season in each year of the study. Mean residency for highly resident sharks was estimated at 55.5 ± 175.5 SE (95% CI 49.5 – 730.0) days, 58.3 ± 161.7 SE (95% CI 23.2 – 81.4) days for seasonal individuals, and 16.8 ± 1.8 SE (95% CI 14.8 – 22.2) days for infrequent sharks (N = 130). Conclusions The difference in residency patterns between frequently sighted and infrequent individuals was almost fourfold. This shift in residency could have long-term implications for ca. 15% of identified whale sharks at the site. We provide insight into the impacts of provisioning on shark movements and inform the debate surrounding the future of this controversial activity.

Background Whale shark tourism is increasingly popular at coastal predictable aggregations around the world. However, only one description accounts for provisioning of whale sharks (Rhincodon typus), which is at Oslob, Philippines, where sharks are provisioned between 6 am and 1 pm daily within a demarked tourist interaction area. Understanding the potential effects of provisioning on the behaviour of this species is important for their conservation. Approach To investigate whether whale shark diving behaviour was affected by the provisioning, four whale sharks with known extended residency at the study site were tagged with CEFAS G5 temperature-depth-recorder (TDR) tags. Three individuals were juvenile males with estimated total lengths of 4.5, 5.0 and 6.5 m (P-432, P-480 and P-403 respectively), and a fourth individual was a juvenile female measuring 5.5 m (P-385). A Hawaiian-sling spear pole was used to deliver stainless steel anchors with a tether carrying a swivel 10 cm into the subdermal layer of the whale sharks on the ventral side between the first dorsal fin and the first lateral ridge. Three TDR tags were randomly deployed amongst the individuals over a period of 18 months. Linear mixed effect models were used to test how attendance at the provisioning site affected shark depth use and variability. Results Tags were deployed for an average duration of 49.5 provisioned days (sharks present daily at the site) and 33.8 non-provisioned days (sharks were absent from the site). The deepest dive was recorded by P-403 to 1,251 m, at a minimum temperature of 12.1 °C. The tags revealed a pronounced shift in habitat use by individuals when away from the provisioning site. Specifically, during provisioned days, time spent at the surface (0 – 2 m) between 6 am and 1 pm was ca. six times longer than during non-provisioned days. During provisioned days, deep dives occurred mostly near or at the end of the provisioning activities (i.e. 10 am to 2 pm), whereas on non-provisioned days, deep dives occurred mostly between 4 am and 10 am. This shift could suggest that whale sharks have a need to thermoregulate following a prolonged period of time at the surface where temperatures regularly exceed 31 °C. Conclusions The use of TDR tags on whale sharks revealed modified diving behaviour at Oslob, a unique provisioning site. This behavioural modification should be considered when developing guidelines for sustainable tourism and conservation measures for the species.

While shark-based tourism is a rapidly growing global industry, there is ongoing controversy about the effects of provisioning on the target species. This study investigated the effect of feeding on whale sharks (Rhincodon typus) at a provisioning site in Oslob, Cebu, in terms of arrival time, avoidance and feeding behaviour using photo-identification and focal follows. Additionally, compliance to the code of conduct in place was monitored to assess tourism pressure on the whale sharks. Newly identified sharks gradually arrived earlier to the provisioning site after their initial sighting, indicating that the animals learn to associate the site with food rewards. Whale sharks with a long resighting history showed anticipatory behaviour and were recorded at the site on average 5 min after the arrival of feeder boats. Results from a generalised linear mixed model indicated that animals with a longer resighting history were less likely to show avoidance behaviour to touches or boat contact. Similarly, sequential data on feeding behaviour was modelled using a generalised estimating equations approach, which suggested that experienced whale sharks were more likely to display vertical feeding behaviour. It was proposed that the continuous source of food provides a strong incentive for the modification of behaviours, i.e., learning, through conditioning. Whale sharks are large opportunistic filter feeders in a mainly oligotrophic environment, where the ability to use novel food sources by modifying their behaviour could be of great advantage. Non-compliance to the code of conduct in terms of minimum distance to the shark (2 m) increased from 79% in 2012 to 97% in 2014, suggesting a high tourism pressure on the whale sharks in Oslob. The long-term effects of the observed behavioural modifications along with the high tourism pressure remain unknown. However, management plans are traditionally based on the precautionary principle, which aims to take preventive actions even if data on cause and effect are still inconclusive. Hence, an improved enforcement of the code of conduct coupled with a reduction in the conditioning of the whale sharks through provisioning were proposed to minimise the impacts on whale sharks in Oslob.

Provisioning wildlife for tourism is a controversial yet widespread practice. We analysed the residency patterns of juvenile whale sharks ( Rhincodon typus ) in Oslob, Philippines, where provisioning has facilitated a large shark-watching operation since 2011. We identified 208 individual sharks over three years, with an average of 18.6 (s.d. = 7.8, range = 6–43) individuals sighted per week. Weekly shark abundance varied seasonally and peak-season abundance (approx. May–November) increased across years. Whale sharks displayed diverse individual site visitation patterns ranging from a single visit to sporadic visits, seasonal residency and year-round residency. Nine individuals became year-round residents, which represents a clear response to provisioning. The timing of the seasonal peak at Oslob did not align with known non-provisioned seasonal aggregations elsewhere in the Philippines, which could suggest that seasonal residents at Oslob exploit this food source when prey availability at alternative sites is low. Since prolonged residency equates to less time foraging naturally, provisioning could influence foraging success, alter distributions and lead to dependency in later life stages. Such impacts must be carefully weighed against the benefits of provisioning (i.e. tourism revenue in a remote community) to facilitate informed management decisions.

This study represents the first description of whale sharks, Rhincodon typus, occurring at a provisioning site in Oslob, Cebu, Philippines. Frequent observations of sharks are often difficult, even at tourism sites, giving rise to provisioning activities to attract them. The present study provides repeated longitudinal data at a site where daily provisioning activities took place, and whale sharks were present every day. A total of 158 individual whale sharks were photographically identified between Mar 2012 and Dec 2013, with 129 males (82%), 19 females (12%) and 10 (6%) of undetermined sex. Mean estimated total length was 5.5 m (±1.3 m S.D.). Twenty individuals were measured with laser photogrammetry to validate researchers' estimated sizes, yielding a good correlation (r (2) = 0.83). Fifty-four (34%) individuals were observed being hand-fed by local fishermen (provisioned), through in-water behavioural observations. Maximum likelihood methods were used to model mean residency time of 44.9 days (±20.6 days S.E.) for provisioned R. typus contrasting with 22.4 days (±8.9 days S.E.) for non-provisioned individuals. Propeller scars were observed in 47% of the animals. A mean of 12.7 (±4.3 S.D.) R. typus were present in the survey area daily, with a maximum of 26 individuals (Aug 10 2013) and a minimum of 2 (Dec 6 2012). Twelve (8%) individuals were seen on at least 50% of survey days (n = 621), with a maximum residency of 572 days for one individual (P-396). Twenty four individuals were photographically identified across regional hotsposts, highlighting the species' migratory nature and distribution. Extended residency and differences in lagged identification rates suggest behavioural modification on provisioned individuals, underlying the necessity for proper management of this tourism activity.

Background. Provisioning is a growing practice used to facilitate wildlife-tourist interaction, especially with elusive marine species, but still little is known about its effect on the host species. This work discusses the practice, effect and proposed measures to manage the whale shark provisioning activities and related tourism industry in the waters of Oslob, Philippines. Methods. Since March 2012, the research team has been studying daily the whale shark population, the tourism industry and its compliances with the local and national laws. During 443 days of survey, 135 individual whale sharks where identified within the interaction area, 197h of shark behavioral observations and tourist compliance surveys have been collected along with 45 biopsy samples, 1000h of dive profiles from TDR tags and 500 tourist satisfaction questionnaires. Results. Since its official opening in January 2012 more than 140,000 interaction tickets have been sold bringing over 1M USD to the local community and making it one of the largest marine wildlife tourist attractions in South East Asia. The benefits for the community and regional economy are undeniable, however behavioral modification, extended residency time, poor nutritional value of provided food and thermal stress related to the extended permanence in shallow water together with habitat destruction caused by poor diving practices and unregulated coastal developments are some of the quantified side effects of this industry. Conclusion. A series of meeting with the stakeholders and an education campaign have been initiated as bottom up approach and an adaptive management model based on the identification of the limits of acceptable change is being developed in collaboration with the Authorities to address current limitations in the long-term sustainable management of the whale shark watching industry in Oslob.