Microplastics in fecal samples of whale sharks (Rhincodon typus) and from surface water in the Philippines

AbstractMarine plastic abundance has increased over the past 60 years and microplastics (< 5 mm) constitute a primary component of such litter. Filter-feeding megafauna, such as the whale shark, might be particularly affected by microplastic pollution as their feeding mode requires filtration of up to thousands of cubic meters of water. In addition, the habitat range of whale sharks intersects with several recognized microplastic pollution hotspots, among which is the Coral Triangle. Direct evidence for microplastic ingestion in whale sharks however, has not yet been presented. Here we show that whale shark scat collected in the Philippines from 2012 to 2019 contained a mean of 2.8 microplastics g− 1. Contrary to our expectations, the microplastic concentration in the scat remained consistent from 2012 to 2019. Water samples from the study site in 2019 indicated that the local microplastic pollution (5.83 particles m− 3) was higher than in surface waters in other whale shark habitats, but well below other pollution hot-spots found in Southeast Asia and China (range: 100–4100 particles m− 3). With the predicted growth in plastic use, leading to increased plastic marine pollution, whale sharks are expected to become more exposed to this form of pollution. To what extent microplastic ingestion impacts the overall health status of this endangered species remains an open question.

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Satellite tracking of juvenile whale sharks in the Sulu and Bohol Seas, Philippines

PeerJ ◽

10.7717/peerj.5231 ◽

2018 ◽

Vol 6 ◽

pp. e5231 ◽

Cited By ~ 3

Author(s):

Gonzalo Araujo ◽

Christoph A. Rohner ◽

Jessica Labaja ◽

Segundo J. Conales ◽

Sally J. Snow ◽

...

Keyword(s):

Population Decline ◽

High Mobility ◽

Iucn Red List ◽

The Philippines ◽

Eastern Coast ◽

Whale Shark ◽

Sulu Sea ◽

The Pacific ◽

Whale Sharks ◽

The Pacific Ocean

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.

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Measuring Perceived Crowding in the Marine Environment: Perspectives from a Mass Tourism "swim-With" Whale Shark Site in the Philippines

Tourism in Marine Environments ◽

10.3727/154427319x15677721896465 ◽

2019 ◽

Vol 14 (4) ◽

pp. 211-230 ◽

Cited By ~ 5

Author(s):

Jackie A. Ziegler ◽

Gonzalo Araujo ◽

Jessica Labaja ◽

Christine Legaspi ◽

Sally Snow ◽

...

Keyword(s):

Marine Environment ◽

Local Community ◽

The Philippines ◽

Whale Shark ◽

Mass Tourism ◽

Management Interventions ◽

The Social ◽

Visual Approach ◽

Whale Sharks ◽

Negative Impacts

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.

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Photo-ID and telemetry highlight a global whale shark hotspot in Palawan, Philippines

Scientific Reports ◽

10.1038/s41598-019-53718-w ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 4

Author(s):

Gonzalo Araujo ◽

Ariana Agustines ◽

Brian Tracey ◽

Sally Snow ◽

Jessica Labaja ◽

...

Keyword(s):

Satellite Telemetry ◽

Species Conservation ◽

The Philippines ◽

Whale Shark ◽

Population Declines ◽

East Kalimantan ◽

Archival Tags ◽

Social Media Platforms ◽

Whale Sharks ◽

Local Operators

AbstractThe 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 <1 year later. Similarly, another tagged whale shark returned to the site at a similar periodicity after reaching the Malay-Filipino border. One individual whale shark first identified in East Kalimantan, Indonesia by a citizen scientist was resighted in Honda Bay ~3.5 years later. Honda Bay is a globally important site for the endangered whale shark with connectivity to two neighbouring countries, highlighting the need for international cooperation to manage the species.

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Implementing the London Dumping Convention in East Asia

Asia-Pacific Journal of Ocean Law and Policy ◽

10.1163/24519391-00202004 ◽

2017 ◽

Vol 2 (2) ◽

pp. 247-267 ◽

Cited By ~ 1

Author(s):

Keyuan Zou ◽

Lei Zhang

Keyword(s):

South Korea ◽

East Asia ◽

Carbon Storage ◽

Marine Pollution ◽

East Asian ◽

The Philippines ◽

New Challenges ◽

The Republic ◽

London Protocol ◽

First Time

In 1972, the Convention on the Prevention of Marine Pollution by Dumping of Wastes and Other Matter (London Convention) was negotiated. It is a global treaty, for the first time, to regulate dumping of waste at sea worldwide. Following this global endeavor, the Protocol to the London Convention (London Protocol) was later agreed to further modernize the London Convention so as to reinforce the management of dumping of waste at sea. While in East Asia, only China, Japan, the Republic of Korea (South Korea) and the Philippines have acceded to the Convention and its Protocol, other countries do not show their willingness to sign them. Against this background, this article will address the responses of these East Asian states to the implementation of the London Convention, and analyze and assess their relevant laws and regulations with particular reference to China’s practice. In addition, it will focus on new challenges, such as offshore carbon storage, to the London Convention.

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Sizing and scarring of whale shark (Rhincodon typus Smith, 1828) in the Cenderawasih Bay National Park

Jurnal Iktiologi Indonesia ◽

10.32491/jii.v21i3.587 ◽

2021 ◽

Vol 21 (3) ◽

pp. 199-213

Author(s):

Yusup A Jentewo ◽

Roni Bawole ◽

Tresia S Tururaja ◽

Mudjirahayu Mudjirahayu ◽

Zeth Parinding ◽

...

Keyword(s):

National Park ◽

The Body ◽

Whale Shark ◽

Gill Slit ◽

Rhincodon Typus ◽

Photo Identification ◽

Dorsal Fin ◽

Total Length ◽

Whale Sharks ◽

Photo Collection

This study aims to determine the total length and scar condition of the body of whale sharks (Rhincodon typus) in Cendrawasih Bay National Park (TNTC), Papua-Indonesia. Photo-identification was used to identify individuals of the whale shark R. typus based on spot patterns behind the last gill slit of each individual. Photo-identification was also used to determine the scar of the whale shark. The total length of whale sharks were estimated based on the length of a snorkeller (assumed to be 1.6 m) swimming alongside the whale shark. We identified 21 individuals of R. typus. Of these 21 individuals, 14 were new sightings and seven were re-sightings that have been recorded in the previous photo collection database. R. typus ranged in size from 2 to 5 m total length (average 3.78 m, ±0,86, N= 21). Based on their size, all individuals of whale shark were categorized as juvenile. 52% of R. typus identified had scars and 38 % were not and 10% were unknown. The majority of whale sharks had amputation (12 individuals) and abrasion (7 individuals) scars. Scars occurred most often on the caudal fin and dorsal fin, five and four individuals respectively. This information is useful for understanding potential threats and designing better management programmes for R. typus conservation in TNTC.

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presence of whale sharks based on oceanographic variations in Cenderawasih Bay National Park, Papua, Indonesia

Biodiversitas Journal of Biological Diversity ◽

10.13057/biodiv/d221129 ◽

2021 ◽

Vol 22 (11) ◽

Author(s):

JAFRY FERDINAN Manuhutu ◽

DEWA GEDE RAKA WIADNYA ◽

ABU BAKAR SAMBAH ◽

ENDANG YULI HERAWATI

Keyword(s):

National Park ◽

Additive Model ◽

Environmental Parameters ◽

Analysis Data ◽

Current Speed ◽

Habitat Modeling ◽

Sea Surface ◽

Observation Data ◽

Whale Shark ◽

Whale Sharks

Abstract. Manuhutu JF, Wiadnya DGR, Sambah AB, Herawati EY. 2021. The presence of whale sharks based on oceanographic variations in Cenderawasih Bay National Park, Papua, Indonesia. Biodiversitas 22: 4948-4955. Oceanographic factors have an important role in the study of estimating the distribution of fish resource habitats. Sea Surface Temperature (SST), Sea Surface Chlorophyll (SSC), Current Speed, Sea Surface Height (SSH), and bathymetry are important parameters that have been used in estimating the habitat of certain species. Through analyzing these environmental factors, research on the appearance and distribution of whale shark habitats in the Cenderawasih Bay National Park in Papua, Indonesia, utilized field observation data and satellite imagery. This study applied data on the presence of whale sharks and oceanographic parameter data from satellite recordings during 2019 – 2020. Analysis of the relationship and habitat modeling between the monthly presence of whale sharks and environmental parameters was carried out through the Generalized Additive Model (GAM) statistical approach and spatial analysis through the Geographic Information System approach. In the GAM analysis, data on the presence of whale sharks was used as a response variable. In contrast, the predictor variables consisted of SST, SSC, current speed, SSH, and bathymetric data. The results showed that the highest frequency of whale shark presence occurred in the transitional monsoon, with an average presence of 31.77 ± 4.00 %. The study also showed that all predictors showed a highly significant relationship (P < 0.001) to the number of whale sharks present. SST values range from 30.3 – 31.3 °C, SSC of 0.39 – 0.86 mg/L, the current speed of 0.46 – 0.65 m/s, SSH showed 0.63 to 1.00 cm, and bathymetry between 40 – 50 m . In the GAM model, the SST and SSC parameters were the two most important parameters that affect the presence of whale sharks, followed by SSHD, depth (bathymetry), and current parameters.

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Regional connectivity of whale sharks demonstrated using photo-identification – Western Atlantic, 1999 - 2013

10.7287/peerj.preprints.98 ◽

2013 ◽

Author(s):

Jennifer McKinney ◽

Eric R Hoffmayer ◽

Jason Holmberg ◽

Rachel Graham ◽

Rafael de la Parra ◽

...

Keyword(s):

Population Size ◽

Transition Probabilities ◽

Regional Cooperation ◽

Individual Heterogeneity ◽

Whale Shark ◽

Western Atlantic ◽

Entire Study ◽

Photo Identification ◽

Initial Identification ◽

Whale Sharks

Background: Although whale sharks (Rhincodon typus) occur circum-globally, most studies focus on feeding aggregations in small regional areas. Photo identification is a proven tool in assessing population size and structure. While population estimates have been obtained for individual aggregation sites, there has been a lack of broader estimates despite known movement. The aim of this work is to demonstrate connectivity throughout the Gulf of Mexico (GOM) and Caribbean, and provide the first regional population estimate. Methods: Photographs submitted to the ECOCEAN Whale Shark Photo-ID Library Sightings were used to identify individual sharks using techniques described in Holmberg et al. (2009). Sightings data were used to assess the lagged identification rate (LIR) in order to investigate residency, regional mixing, population size, and transition probabilities using modules within SOCPROG 2.4. Results: Identifications from 1998 – 2013, were obtained from Belize (n =132), Mexico (n=3642), Honduras (n = 360), and the USA (n=147). Fifty-four individual sharks were seen in more than one country and used for analysis. For the entire study area, LIR decreased rapidly between one and 64-127 (mean 94.4) days then slightly increased between 256-511 (mean 381.2) days, suggesting a near-annual resighting periodicity. Estimates of mean population size from the best-fitting model were 1897.39 ± 414.30 S.E. (95% C.I. 1191.77 – 2784.03). Evidence suggests individual heterogeneity in movement patterns. Resightings were most likely to occur in the country where initial identification occurred, with the exception of Belize. The highest site fidelity was in Mexico, followed by USA. Conclusions: This study demonstrated individual heterogeneity, fidelity to initial identification site and regional linkages. These data suggest that national and regional cooperation is required for successful whale shark management in the West Atlantic.

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In-water observations highlight the effects of provisioning on whale shark behaviour at the world's largest whale shark tourism destination

Royal Society Open Science ◽

10.1098/rsos.200392 ◽

2020 ◽

Vol 7 (12) ◽

pp. 200392

Author(s):

Christine Legaspi ◽

Joni Miranda ◽

Jessica Labaja ◽

Sally Snow ◽

Alessandro Ponzo ◽

...

Keyword(s):

Strong Predictor ◽

Management Strategies ◽

Code Of Conduct ◽

Mixed Effects ◽

Tourism Industry ◽

Mixed Effects Models ◽

Whale Shark ◽

Whale Sharks ◽

External Stimuli ◽

The Relationship

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.

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Feeding habits of the burrowing shrimp Alpheus macellarius

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315404010641h ◽

2004 ◽

Vol 84 (6) ◽

pp. 1199-1202 ◽

Cited By ~ 15

Author(s):

N.E. Palomar ◽

M.A. Juinio-Meñez ◽

I. Karplus

Keyword(s):

Organic Matter ◽

Feeding Habits ◽

Organic Matter Content ◽

The Philippines ◽

Matter Content ◽

Food Sources ◽

Feeding Mode ◽

Field Surveys ◽

Sea Grass ◽

Deposit Feeding

The diet and feeding behaviour of the burrowing shrimp Alpheusmacellarius (Decapoda: Alpheidae) in sea grass beds in the Philippines were evaluated in the present study through field and laboratory activities. Sediment organic matter and sea grass appear to be important food sources for the shrimp based on the combined results of field surveys, gut content, stable isotope (δ13C) and sediment C content analyses. There was a significant positive correlation between organic matter content in the sediment and shrimp densities. In terms of behaviour, observations under controlled set-ups detected marked trends in duration and frequency of feeding. Feeding bouts became longer and more recurrent as the days progressed. Periodicity was exhibited with burrowing generally performed in the morning and feeding in the afternoon. A deposit-feeding mode was predominant in tank conditions as demonstrated by the shrimp's behaviour and burrow features.

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