Microplastics on the menu: Plastics pollute Indonesian Manta Ray and Whale Shark feeding grounds

The implications of plastic pollution, including microplastics, on marine ecosystems and species are increasingly seen as an environmental disaster. Yet few reports focus on filter-feeding megafauna in regions heavily impacted by plastic pollution, such as Indonesia in the Coral Triangle, a global marine biodiversity hotspot. Here, we evaluate plastic abundance and characterize debris from feeding grounds for manta rays Mobula alfredi and whale sharks Rhincodon typus in three coastal locations in Indonesia: Nusa Penida Marine Protected Area, Komodo National Park, and Pantai Bentar, East Java. A 200 μm plankton net was used to sample the top 0.5 m of the water column (‘trawl survey’) and floating plastics were assessed along ∼440 m long transects (‘visual survey’) during the Indonesian north-west (wet) and south-east (dry) monsoon seasons during 2016–2018. Microplastics were identified visually, measured and categorized from trawl samples, and larger floating plastics were counted and categorized visually from boats. Plastic abundance ranged widely from 0.04 to 0.90 pieces m–3 (trawl survey) and 210 to 40,844 pieces km–2 (visual survey). Results from linear models showed significant seasonal and location differences in estimated plastic abundance for trawl and visual surveys in Nusa Penida and Komodo. Plastic abundance was up to ∼ 44 times higher in the wet than the dry season, with the largest seasonal effect observed in Nusa Penida. Overall, small pieces  50% combined) were the most prevalent plastics. Theoretical plastic ingestion rates were calculated using estimated filtration volumes of manta rays and whale sharks and the mean plastic abundance in their feeding grounds. Upper plastic ingestion estimates for manta rays were ∼63 and 25 pieces h–1 for Nusa Penida and Komodo locations, respectively, and ∼137 pieces h–1 for whale sharks in Java. Analysis of manta ray egested material confirmed plastic ingestion, the consequences of which might include exposure to toxic plastic additives and adhered persistent organic pollutants. Communicating this information to communities who stand to benefit from healthy megafauna populations might help local governments as they work toward reducing plastics in the marine environment

Microplastics: No small problem for filter-feeding megafauna

Microplastic pollution can impact filter-feeding marine megafauna, namely mobulid rays, filter-feeding sharks, and baleen whales. Emerging research on these flagship species highlights potential exposure to microplastic contamination and plastic-associated toxins. Research and its wide communication are needed to understand the magnitude of the issue and improve marine stewardship

Microplastics: No small problem for filter-feeding megafauna

Microplastic pollution can impact filter-feeding marine megafauna, namely mobulid rays, filter-feeding sharks, and baleen whales. Emerging research on these flagship species highlights potential exposure to microplastic contamination and plastic-associated toxins. Research and its wide communication are needed to understand the magnitude of the issue and improve marine stewardship

Contrasting habitat use and population dynamics of reef manta rays within the Nusa Penida marine protected area, Indonesia

Manta rays (Mobula spp.) are highly valued in nature-based tourism globally. In Indonesia, although manta rays are protected, critical information is lacking on their habitat use, population dynamics and movements. We investigate the population structure and residency patterns of reef manta rays (Mobula alfredi) in the Nusa Penida Marine Protected Area (MPA). From photo-identification data logged by citizen scientists and trained observers (mantamatcher.org), we identified 624 reef manta rays from 5,913 sightings (January 2012–April 2018) based on their unique ventral coloration patterns. Year-round records were collected from two shallow (<20 m) reefs – Manta Bay (MB; n = 3,029 sightings) and Manta Point (MP; n = 3,058) – that are used frequently by tourism operators. Maximum likelihood techniques and a Markov movement analysis were used to model residency patterns and movement between these sites within the MPA. Manta rays at MB were predominantly male (64%, n = 261 individuals), with immature males (14%, n = 59) being sighted most frequently (39%, n = 1,170). In contrast, few immature individuals were sighted at MP (6%, n = 28), and they were sighted on few occasions (2%, n = 45), while mature female manta rays comprised 26% (n = 127) of the MP community and were the most frequently sighted (48%, n = 1,413). Lagged identification rates indicated high site fidelity at each location. However, 44% (n = 278) of individuals moved between the two sites and cumulative discovery curves showed a continued recruitment of individuals over the 6 years of the study. In addition, the behaviors displayed by the manta rays differed markedly between the two sites: MB appears to be a foraging ground, especially for juveniles, and potentially a nursery, while MP is used mainly for cleaning and courtship, indicating a social and reproductive site. Reproductive behavior coincided with the peak annual sightings in May. To prevent disturbance to this threatened species by tourism, regulations for the number of boats and interactions, especially during key reproductive times should be considered. Further, strict fishing regulation in the area is recommended as fishing gear entanglement was identified as a threat to this population

Residency, movement patterns, behavior and demographics of reef manta rays in Komodo National Park

Background The reef manta ray (Mobula alfredi) is a globally threatened species and an iconic tourist attraction for visitors to Indonesia’s Komodo National Park (NP). In 2013, manta ray fishing was banned in Komodo NP and its surroundings, preceding the nationwide manta ray protection in 2014. Over a decade ago, a previous acoustic telemetry study demonstrated that reef manta rays had high fidelity to sites within the park, while more recent photo-identification data indicated that some individuals move up to 450 km elsewhere. Characterization of manta ray demographics, behavior, and a focused assessment on site use of popular tourism locations within the park is vital to assist the Komodo NP Management Authority formulate appropriate manta ray conservation and management policies. Methods This study uses a long-term library (MantaMatcher.org) of photo-identification data collected by researchers and citizen scientists to investigate manta ray demographics and habitat use within the park at four sites frequented by tour operators: Cauldron, Karang Makassar, Mawan, and Manta Alley. Residency and movements of manta rays were investigated with maximum likelihood analyses and Markov movement models. Results A total of 1,085 individual manta rays were identified from photographs dating from 2013 to 2018. In general, individual manta rays displayed a higher affinity to specific sites than others. The highest re-sighting probabilities came from the remote southern site, Manta Alley. Karang Makassar and Mawan are only ~5 km apart; however, manta rays displayed distinct site affinities. Exchange of individuals between Manta Alley and the two central sites (~35.5 km apart) occurred, particularly seasonally. More manta rays were recorded traveling from the south to the central area than vice versa. Female manta rays were more mobile than males. Similar demographic groups used Karang Makassar, Mawan, and Manta Alley for foraging, cleaning, cruising, or courtship activities. Conversely, a higher proportion of immature manta rays used the northern site, Cauldron, where foraging was commonly observed. Fishing gear-related injuries were noted on 56 individuals (~5%), and predatory injuries were present on 32 individuals (~3%). Tourism within the park increased from 2014 to 2017, with 34% more dive boats per survey at Karang Makassar and Mawan. Discussion The Komodo NP contains several distinct critical habitats for manta rays that encompass all demographics and accommodate seasonal manta ray movements. While the present study has not examined population trends, it does provide foundational data for such work. Continued research into manta ray abundance, long-range movements, and identifying and protecting other critical aggregation areas within the region is integral to securing the species’ recovery. We provide management recommendations to limit undue pressure on manta rays and their critical habitats from tourism

Efficiency of tactile contact in rhythmic gymnastics

Секованич Мирьяна, аспирант, Российский университет спорта «ГЦОЛИФК», Москва, Россия; мастер спорта РФ по художественной гимнастике, тренер по художественной гимнастике, Московская комплексная спортивная школа олимпийского резерва «Север» Департамента спорта города Москвы, Москва, Россия. Германов Геннадий Николаевич, доктор педагогических наук, профессор, заслуженный работник физической культуры РФ, профессор кафедры педагогики, Российский университет спорта «ГЦОЛИФК», Москва, Россия. Колесникова Екатерина Сергеевна, кандидат педагогических наук, доцент, мастер спорта международного класса по спортивной гимнастике, доцент кафедры теории и методики гимнастики, Российский университет спорта «ГЦОЛИФК», Москва, Россия. Черенкова Екатерина Сергеевна, кандидат педагогических наук, мастер спорта по спортивной акробатике, доцент кафедры сложно-координационных и прикладных видов спорта, Воронежская государственная академия спорта, Воронеж, Россия. Готовцева Яна Владимировна, мастер спорта международного класса по акробатике, доцент кафедры физического воспитания и спорта, Воронежский государственный университет, Воронеж, Россия. Mirjana Sekovanich, post-graduate student, Russian University of Sports “SCOLIPE”, Moscow, Russia; master of sport, rhythmic gymnastics coach, Moscow Comprehensive Sports School of Olympic Reserve “Sever” of the Moscow Department of Sports, Moscow, Russia. Gennady N. Germanov, Doctor of Pedagogical Sciences, Professor, Honored Worker of Physical Education of Russia, Professor of the Department of Pedagogy, Russian University of Sports “SCOLIPE”, Moscow, Russia. Ekaterina S. Kolesnikova, Candidate of Pedagogical Sciences, Associate Professor, International Class Master of Sport (Artistic Gymnastics), Associate Professor of the Department of Theory and Methods of Gymnastics, Russian University of Sports “SCOLIPE”, Moscow, Russia. Ekaterina S. Cherenkova, Candidate of Pedagogical Sciences, Associate Professor, Master of Sport (Acrobatics), Associate Professor of the Department of Complex Coordination and Applied Sports, Voronezh State Academy of Sports, Voronezh, Russia. Yana V. Gotovtseva, International Class Master of Sport (Acrobatics), Associate Professor of the Department of Physical Education and Sports, Voronezh State University, Voronezh, Russia.Цель исследования – определить эффективность тактильных воздействий при развитии физических качеств и в обучении движениям на этапе начальной подготовки девочек 5–8 лет, занимающихся художественной гимнастикой. Материалы и методы. Методология исследования предусматривала ранжирование, классифицирование, проведение экспертных оценок. В исследовании осуществлено анкетирование 76 тренеров и высококвалифицированных спортсменок по художественной гимнастике. Использовались стандартные методы обработки с использованием пакетов статистических программ Stadia 8.0, Microsoft Excel. Результаты. В исследовании определено соотношение средств подготовки в структуре невербальных воздействий тренера по художественной гимнастике, где тактильным средствам рекомендуется отводить до 20 % за счет уменьшения объема кинетических, такесических, визуальных и акустических средств в пользу тактильных, и эту пропорцию следует признать рациональным и паритетным соотношением, приводящим к значительному росту показателей физической подготовленности и повышению качества движений. Выявлены условия эффективного применения тактильных средств в обучении и развитии юных спортсменок-художниц при начальных занятиях видом спорта, предусматривающие применение определенных видов телесных прикосновений в структуре тактильной коммуникации тренера. Заключение. Тактильные средства следует признать как самостоятельные обучающие и развивающие единицы в структуре двигательной деятельности, расширяющие возможности педагогического сотрудничества тренера и юной спортсменки, содействующие установлению взаимоприемлемых и доверительных отношений, потенцирующие эффект обучения и развития девочек на этапе начальной подготовки, приводящие к позитивным сдвигам в приросте двигательных способностей и содействующие освоению базовых элементов в художественной гимнастике. Aim. The paper aims to measure the effectiveness of tactile contact in the development of physical qualities and learning movements among 5–8-year-old girls engaged in rhythmic gymnastics. Materials and methods. The research methodology included ranking, classification, and expert assessment procedures. Seventy-six coaches and highly skilled gymnasts were surveyed. Data processing was performed with standard software, including Stadia 8.0 and Microsoft Excel. Results. It is recommended that the amount of tactile means be increased by up to 20% by reducing kinetic, takesik, visual, and acoustic means in favor of those tactile. This ratio should be recognized as logical, as it results in significant improvements in physical fitness and movement quality. The effective use of tactile means has been revealed in young female gymnasts at the beginning of their training experience. Conclusion. Tactile means should be recognized as an independent instrument that expands the prospects for pedagogical cooperation between a trainer and a young athlete, contributes to mutually acceptable and trusting relationships, enhances learning and development at the beginning of athletic experience, leads to positive changes in motor abilities, and promotes the acquisition of basic elements in rhythmic gymnastic

It's not all black and white: Investigating colour polymorphism in manta rays across Indo-Pacific populations

Intraspecific colour polymorphisms have been the focus of numerous studies, yet processes affecting melanism in the marine environment remain poorly understood. Arguably, the most prominent example of melanism in marine species occurs in manta rays (Mobula birostris and Mobula alfredi). Here, we use long-term photo identification catalogues to document the frequency variation of melanism across Indo-Pacific manta ray populations and test for evidence of selection by predation acting on colour morph variants. We use mark–recapture modelling to compare survivorship of typical and melanistic colour morphs in three M. alfredi populations and assess the relationship between frequency variation and geographical distance. While there were large differences in melanism frequencies among populations of both species (0–40.70%), apparent survival estimates revealed no difference in survivorship between colour morphs. We found a significant association between phenotypic and geographical distance in M. birostris, but not in M. alfredi. Our results suggest that melanism is not under selection by predation in the tested M. alfredi populations, and that frequency differences across populations of both species are a consequence of neutral genetic processes. As genetic colour polymorphisms are often subjected to complex selection mechanisms, our findings only begin to elucidate the underlying evolutionary processes responsible for the maintenance and frequency variation of melanism in manta ray populations

Research priorities to support effective manta and devil ray conservation

Manta and devil rays are filter-feeding elasmobranchs that are found circumglobally in tropical and subtropical waters. Although relatively understudied for most of the Twentieth century, public awareness and scientific research on these species has increased dramatically in recent years. Much of this attention has been in response to targeted fisheries, international trade in mobulid products, and a growing concern over the fate of exploited populations. Despite progress in mobulid research, major knowledge gaps still exist, hindering the development of effective management and conservation strategies. We assembled 30 leaders and emerging experts in the fields of mobulid biology, ecology, and conservation to identify pressing knowledge gaps that must be filled to facilitate improved science-based management of these vulnerable species. We highlight focal research topics in the subject areas of taxonomy and diversity, life history, reproduction and nursery areas, population trends, bycatch and fisheries, spatial dynamics and movements, foraging and diving, pollution and contaminants, and sub-lethal impacts. Mobulid rays remain a poorly studied group, and therefore our list of important knowledge gaps is extensive. However, we hope that this identification of high priority knowledge gaps will stimulate and focus future mobulid research