Describing the population structure of Rhincodon typus occurring in the waters of Oslob– Cebu, Philippines– between March 2012 and June 2013, during the provisioning interaction hours.

Background: Prior to this study, the aggregation of whale sharks in the waters of Oslob had never been described. Provisioning (Orams, 2002) activities started in late 2011, and systematic data collection in March 2012, attracting over 100,000 tourists in the first year, and is currently the most reliable aggregation of R. typus in the Philippines. Methods: Daily in-‐water photographic identification was used as a non-‐invasive means to describe the population throughout the study period. A total of 135 sharks were identified, and IDs were independently matched by three researchers to minimize error. Photogrammetry (Rohner, 2011) was adopted to complement population description. Results: Daily sightings ranged from 2 to 23 different animals in the interaction area (mean=11.14). A total of 109 males, 15 females and 11 R. typus of undetermined sex were described. The size was estimated for 73.3% of the population, with an average of 5.36m ±1.3m. Photogrammetry posed a mean of 5.63m ±0.59m on 14 sharks, 6.75% >than researchers’ estimates. Resighting (>1d) was observed in 66.7% of the population. Five individuals were present for >300d (n=443) in the interaction area, with a maximum of 420d. Nine individuals were successfully matched across regional hotspots including Donsol and Southern Leyte. Conclusion: Despite the presence of animals in Oslob year round and the influence of the provisioning, there appears to be a seasonal influx of animals, with a maximum of 46 different animals present in the month of June 2012 and again in May 2013, contrasting with a monthly average of 28.9. It appears these waters are important to the species and it’s paramount to fully investigate the impact of the provisioning on the population of R. typus in the Philippines.

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The Green Revolution shaped the population structure of the rice pathogen Xanthomonas oryzae pv. oryzae

The ISME Journal ◽

10.1038/s41396-019-0545-2 ◽

2019 ◽

Vol 14 (2) ◽

pp. 492-505 ◽

Cited By ~ 10

Author(s):

Ian Lorenzo Quibod ◽

Genelou Atieza-Grande ◽

Eula Gems Oreiro ◽

Denice Palmos ◽

Marian Hanna Nguyen ◽

...

Keyword(s):

Population Structure ◽

Plant Pathogens ◽

Crop Improvement ◽

Green Revolution ◽

Agricultural Practices ◽

The Philippines ◽

Xanthomonas Oryzae ◽

Rice Varieties ◽

Evolutionary Trajectory ◽

The Impact

Abstract The impact of modern agriculture on the evolutionary trajectory of plant pathogens is a central question for crop sustainability. The Green Revolution replaced traditional rice landraces with high-yielding varieties, creating a uniform selection pressure that allows measuring the effect of such intervention. In this study, we analyzed a unique historical pathogen record to assess the impact of a major resistance gene, Xa4, in the population structure of Xanthomonas oryzae pv. oryzae (Xoo) collected in the Philippines in a span of 40 years. After the deployment of Xa4 in the early 1960s, the emergence of virulent pathogen groups was associated with the increasing adoption of rice varieties carrying Xa4, which reached 80% of the total planted area. Whole genomes analysis of a representative sample suggested six major pathogen groups with distinctive signatures of selection in genes related to secretion system, cell-wall degradation, lipopolysaccharide production, and detoxification of host defense components. Association genetics also suggested that each population might evolve different mechanisms to adapt to Xa4. Interestingly, we found evidence of strong selective sweep affecting several populations in the mid-1980s, suggesting a major bottleneck that coincides with the peak of Xa4 deployment in the archipelago. Our study highlights how modern agricultural practices facilitate the adaptation of pathogens to overcome the effects of standard crop improvement efforts.

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The impact of injury on apparent survival of whale sharks (Rhincodon typus) in South Ari Atoll Marine Protected Area, Maldives

Scientific Reports ◽

10.1038/s41598-020-79101-8 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Jessica Harvey-Carroll ◽

Joshua D. Stewart ◽

Daire Carroll ◽

Basith Mohamed ◽

Ibrahim Shameel ◽

...

Keyword(s):

Endangered Species ◽

Protected Area ◽

Local Community ◽

Marine Protected Area ◽

Conservation Strategies ◽

Whale Shark ◽

Apparent Survival ◽

Rhincodon Typus ◽

Whale Sharks ◽

The Impact

AbstractThe whale shark (Rhincodon typus) is an endangered species with a declining global population. The South Ari Atoll Marine Protected Area (SAMPA), Maldives, is one of few locations globally where year-long residency of individuals occurs. This SAMPA aggregation appears to consist almost exclusively of immature males. Due to its year-round residency, this local aggregation is subjected to a high degree of tourism pressure. This ecotourism contributes to the high level of interest and protection offered to whale sharks by the local community. Unfortunately, if regulations are not followed or enforced, tourism can bring with it major stressors, such as accidental injuries. We used POPAN capture-mark-recapture models and lagged identification rate analysis to assess the effect of major injuries on whale shark residency within SAMPA. Injuries may be obtained outside SAMPA. We found individuals with major injuries had a higher apparent survival in the area than those without. Lagged identification rates also demonstrated that sharks with major injuries are more likely to return to the area. We suggest that major injuries result in sharks prolonging their time in the developmental habitat. These findings have implications for individual fitness and the population viability of this endangered species. We propose targeted conservation strategies be considered to protect sharks from further injury. Based on the presented spatio-temporal distributions of sharks, and current local knowledge of sighting patterns, speed limit zones and propeller-exclusion zones should be implemented and enforced. If carried out alongside tourist education, these measures will contribute to the protection of whale sharks within SAMPA and beyond. Furthermore, our results can aid research direction, alongside regulation and enforcement development, at similar sites worldwide.

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Whale sharks Rhincodon typus get cleaned by the blue‐streak cleaner wrasse Labroides dimidiatus and the moon wrasse Thalassoma lunare in the Philippines

Journal of Fish Biology ◽

10.1111/jfb.14464 ◽

2020 ◽

Vol 97 (4) ◽

pp. 1247-1251

Author(s):

Gonzalo Araujo ◽

Joni A. Miranda ◽

Harriet L. Allen ◽

Jessica Labaja ◽

Sally Snow ◽

...

Keyword(s):

The Philippines ◽

The Moon ◽

Labroides Dimidiatus ◽

Rhincodon Typus ◽

Whale Sharks ◽

Thalassoma Lunare

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Scarring patterns of whale sharks, Rhincodon typus , at a provisioning site in the Philippines

Aquatic Conservation Marine and Freshwater Ecosystems ◽

10.1002/aqc.3437 ◽

2020 ◽

Cited By ~ 1

Author(s):

Luke Penketh ◽

Anna Schleimer ◽

Jessica Labaja ◽

Sally Snow ◽

Alessandro Ponzo ◽

...

Keyword(s):

The Philippines ◽

Rhincodon Typus ◽

Whale Sharks

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Can ecotourism change community attitudes towards conservation?

Oryx ◽

10.1017/s0030605319000607 ◽

2020 ◽

pp. 1-10 ◽

Cited By ~ 1

Author(s):

Jackie Ziegler ◽

Gonzalo Araujo ◽

Jessica Labaja ◽

Sally Snow ◽

Joseph N. King ◽

...

Keyword(s):

Ecological Status ◽

The Philippines ◽

Economic Returns ◽

Community Attitudes ◽

Focal Species ◽

Rhincodon Typus ◽

Basic Tenet ◽

Whale Sharks ◽

Tourism Activity ◽

Negative Impacts

Abstract 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.

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Comparing length-measurement methods and estimating growth parameters of free-swimming whale sharks (Rhincodon typus) near the South Ari Atoll, Maldives

Marine and Freshwater Research ◽

10.1071/mf17393 ◽

2018 ◽

Vol 69 (10) ◽

pp. 1487 ◽

Cited By ~ 7

Author(s):

Cameron T. Perry ◽

Joana Figueiredo ◽

Jeremy J. Vaudo ◽

James Hancock ◽

Richard Rees ◽

...

Keyword(s):

Growth Parameters ◽

Measurement Methods ◽

Nursery Ground ◽

The South ◽

Free Swimming ◽

Invasive Approach ◽

Rhincodon Typus ◽

Non Invasive ◽

Whale Sharks ◽

Conservation Concern

Whale sharks (Rhincodon typus) are an endangered species whose growth and reproductive biology are poorly understood. Given their conservation concern, estimating growth parameters, as traditionally derived from vertebral samples of dead animals, is challenging. We used a non-invasive approach to investigate growth parameters of whale sharks frequenting the South Ari Atoll, Maldives, by analysing repeat measurements of free-swimming sharks over a 10-year period. Total lengths of the sharks were estimated by three measurement methods. Visual estimates underestimated the sizes of large sharks, whereas laser and tape measurements yielded results that were similar to one another. The Maldives aggregation consisted of primarily male (91%) juvenile (total length=3.16–8.00m) sharks and sharks new to the area were significantly smaller than were returning sharks, which suggests that this site may constitute a secondary nursery ground. Estimates of von Bertalanffy (VBG) growth parameters for combined sexes (L∞=19.6m, k=0.021year–1) were calculated from 186 encounters with 44 sharks. For males, VBG parameters (L∞=18.1m, k=0.023year–1) were calculated from 177 encounters with 40 sharks and correspond to a male age at maturity of ~25 years and longevity of ~130 years. Differences between these estimates and those from other studies underscore the need for regional studies.

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Daily abundance and residency patterns of whale sharks (Rhincodon typus) at a unique provisioning site in the Philippines

10.5339/qproc.2016.iwsc4.5 ◽

2016 ◽

Author(s):

Jordan Thomson ◽

Gonzalo Araujo ◽

Jessica Labaja ◽

Emer Mccoy ◽

Ryan Murray ◽

...

Keyword(s):

The Philippines ◽

Rhincodon Typus ◽

Whale Sharks

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Feeding the world's largest fish: highly variable whale shark residency patterns at a provisioning site in the Philippines

Royal Society Open Science ◽

10.1098/rsos.170394 ◽

2017 ◽

Vol 4 (9) ◽

pp. 170394 ◽

Cited By ~ 17

Author(s):

Jordan A. Thomson ◽

Gonzalo Araujo ◽

Jessica Labaja ◽

Emer McCoy ◽

Ryan Murray ◽

...

Keyword(s):

Prey Availability ◽

Later Life ◽

The Philippines ◽

Foraging Success ◽

Remote Community ◽

Rhincodon Typus ◽

Individual Site ◽

Whale Sharks ◽

Diverse Individual ◽

Alternative Sites

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.

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