| 1. |
- Abudaya, Mohammed, et al.
(författare)
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Speak of the devil ray (Mobula mobular) fishery in Gaza
- 2018
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Ingår i: Reviews in Fish Biology and Fisheries. - : Springer. - 0960-3166 .- 1573-5184. ; 28:1, s. 229-239
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Tidskriftsartikel (refereegranskat)abstract
- Little is known about the giant devil ray (Mobula mobular), an endangered species endemic to the Mediterranean. Gaza is the only region where this species is targeted, hence, this fishery was studied to address the knowledge gap on fishery interactions, species behavior, and life-history traits. Devil rays have been frequenting this maritime area for at least the past 50 years for a short window from February to April. Landings are reported from 2005 to 2016, along with disc-width (DW) measurements for recent years. A total of 304 M. mobular (over 90% males) were landed in Gaza from 2014 to 2016, most which were mature and appeared to be mating (over 90% of males had sperm-filled claspers), providing critical insight that this area may serve as a mating ground. Yearly landings are shown here to closely match the allowed fishing distance from shore, which changes regularly, indicating that the rays are normally caught between 6 and 12 n.m. offshore. Width-weight conversion parameters are calculated for the first time for this species: a = 2.68 x 10(-6) and b = 4.39. Fresh protein drives this local fishery, as food security is a major issue. An export market for gill plates was reported intermittently, and is no longer possible due to strict trade restrictions. We highlight the lack of awareness of fishers regarding the IUCN's Red List 'Endangered' status of devil rays, and stress the urgent need for national protection of this species, particularly due to the species' very slow life-history traits and probable usage of this area as a mating ground.
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| 2. |
- Croll, Donald A., et al.
(författare)
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Vulnerabilities and fisheries impacts : the uncertain future of manta and devil rays
- 2016
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Ingår i: Aquatic conservation. - : Wiley. - 1052-7613 .- 1099-0755. ; 26:3, s. 562-575
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Forskningsöversikt (refereegranskat)abstract
- 1. Manta and devil rays of the subfamily Mobulinae (mobulids) are rarely studied, large, pelagic elasmobranchs, with all eight of well-evaluated species listed on the IUCN Red List as threatened or near threatened. 2. Mobulids have life history characteristics (matrotrophic reproduction, extremely low fecundity, and delayed age of first reproduction) that make them exceptionally susceptible to overexploitation. 3. Targeted and bycatch mortality from fisheries is a globally important and increasing threat, and targeted fisheries are incentivized by the high value of the global trade in mobulid gill plates. 4. Fisheries bycatch of mobulids is substantial in tuna purse seine fisheries. 5. Thirteen fisheries in 12 countries specifically targeting mobulids, and 30 fisheries in 23 countries with mobulid bycatch were identified. 6. Aside from a few recently enacted national restrictions on capture, there is no comprehensive monitoring, assessment or control of mobulid fisheries or bycatch. Recent listing through the Convention on the International Trade in Endangered Species (CITES) may benefit mobulids of the genus Manta (manta rays), but none of the mobulids in the genus Mobula (devil rays) are protected. 7. The relative economic costs of catch mitigation are minimal, particularly compared with a broad range of other, more complicated, marine conservation issues. Copyright (C) 2015 John Wiley & Sons, Ltd.
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| 3. |
- di Sciara, Giuseppe Notarbartolo, et al.
(författare)
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Devil rays (Chondrichthyes: Mobula) of the Arabian Seas, with a redescription of Mobula kuhlii (Valenciennes in Muller and Henle, 1841)
- 2017
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Ingår i: Aquatic conservation. - : Wiley-Blackwell. - 1052-7613 .- 1099-0755. ; 27:1, s. 197-218
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Tidskriftsartikel (refereegranskat)abstract
- Devil rays (genus Mobula) are pelagic elasmobranchs widely distributed throughout tropical, subtropical and warm-temperate waters. Their occurrence and distribution remains poorly documented in the Arabian Seas region. A review is provided of species occurrence in these water bodies along with a synthesis of regional information on their biology and ecology. Based on the available evidence, five Mobula species occur in the region (M. eregoodootenkee, M. japanica, M. kuhlii, M. tarapacana, and M. thurstoni). Of these, three (M. eregoodootenkee, M. tarapacana and M. thurstoni) were found to occur in the Red Sea, and three (M. eregoodootenkee, M. japanica, and M. kuhlii) were found to occur in the Arabian/Persian Gulf. Mobula japanica and M. kuhlii are reported here for the first time in Gulf waters. All five species were found in the Indian Ocean waters between the Gulf of Aden and Pakistan. To address the still uncertain taxonomy of M. kuhlii, a redescription of this species is provided based on a sample of fresh specimen material. Mobula diabolus is a nomen ambiguum, never used to unambiguously designate any newly described species, and its use should be avoided. Considering the life-history traits that make these species particularly vulnerable to fishing pressure, current levels of exploitation in by-catch fisheries are unlikely to be sustainable, despite the fact that the trade in gill plates does not seem to be prevalent in this region. Critical knowledge gaps unfortunately still exist, crippling effective management and conservation actions. Copyright (c) 2016 John Wiley & Sons, Ltd.
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| 4. |
- di Sciara, Giuseppe Notarbartolo, et al.
(författare)
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Taxonomic status, biological notes, and conservation of the longhorned pygmy devil ray Mobula eregoodoo (Cantor, 1849)
- 2020
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Ingår i: Aquatic conservation. - : John Wiley & Sons. - 1052-7613 .- 1099-0755. ; 30:1, s. 104-122
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Tidskriftsartikel (refereegranskat)abstract
- The longhorned pygmy devil ray Mobula eregoodoo (Cantor, 1849), formerly known as Mobula eregoodootenkee (Bleeker, 1859), is a small mobulid with a disc reaching a maximum width of 1.3 m, widely ranging in tropical and subtropical latitudes across the Indian Ocean, the Indo-Pacific region, and the western Pacific Ocean. A recently emerged opportunity to examine several (n = 47) M. eregoodoo specimens bycaught in bather protection gillnets off New South Wales, Australia, together with new information assembled from other areas of its range, now allows for a redescription of the species, which was incompletely described in the past because of a paucity of specimens. Based on the morphometric, morphological, ecological, and behavioural elements presented here, corroborated by recent genetic investigations, we argue that M. eregoodoo (Cantor, 1849) is a valid species, distinct from shorthorned pygmy devil ray Mobula kuhlii (Muller & Henle, 1841). These findings are contrary to a recent revision of Mobula, where it was assessed as a synonym of M. kuhlii. The accuracy of taxonomic assessments underpins the effectiveness of species conservation, particularly when direct exploitation or bycatch in various fisheries needs to be managed for sustainability. Failing to recognize that two similar-looking species are distinct, such as M. eregoodoo and M. kuhlii, creates uncertainties that could result in mismanagement and underestimating local and global threats of extinction.
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| 5. |
- di Sciara, Giuseppe Notarbartolo, et al.
(författare)
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The giant devil ray Mobula mobular (Bonnaterre, 1788) is not giant, but it is the only spinetail devil ray
- 2020
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Ingår i: Marine Biodiversity Records. - : BioMed Central (BMC). - 1755-2672. ; 13:1
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Tidskriftsartikel (refereegranskat)abstract
- Mobula mobular, a mobulid species once considered a Mediterranean Sea endemic, has received its common name "giant devil ray" based on repeated misidentifications of oceanic manta rays, Mobula birostris, that had strayed into the Mediterranean, where they had never been reported from before. Based on the maximum known size (350 cm disc width) of M. mobular, when compared to some of its congenerics, the giant devil ray is not giant at all. A recent revision of the phylogeny and taxonomy of genus Mobula, which included, amongst other things, the decision to consider the circumtropical spinetail devil ray M. japanica a junior synonym of M. mobular, has caused the latter species to become circumglobal, and the only known mobulid with a tail spine. As a consequence, it is here recommended that the common name of M. mobular be "spinetail devil ray".
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| 6. |
- Geijer, Christina K. A., et al.
(författare)
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Mysticete migration revisited : are Mediterranean fin whales an anomaly?
- 2016
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Ingår i: Mammal Review. - : Wiley. - 0305-1838 .- 1365-2907. ; 46:4, s. 284-296
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Forskningsöversikt (refereegranskat)abstract
- The generally accepted model of Mysticete whale migration is that most individuals undertake seasonal migrations between high and low latitudes. Although numerous exceptions have been described in the literature, the traditional model remains unexamined. This paper represents the first official' challenge to the traditional model of Mysticete migration. We set out to review the current state of knowledge on the Mediterranean fin whale migratory pattern, and to examine whether the small, resident population in the Mediterranean is an anomaly within the framework of the traditional model of Mysticete migration. We investigated the prevalence of alternative migratory strategies among the Mysticete whales, reviewing the migratory habits of the Mediterranean fin whales and those of other fin whale and baleen whale populations. We reach three main conclusions. First, the seasonal behaviour of the resident Mediterranean fin whales is highly dynamic, and a decade of research has not clarified prevailing uncertainties regarding migration patterns. Second, migration strategies similar to those observed in the Mediterranean fin whales are commonly seen in other populations of baleen whales. Third, the traditional model of whale migration is too simplified to describe the repertoire of Mysticete migratory behaviours accurately. We argue that the paradigm of baleen whale migration warrants further scrutiny to account for more complex movement strategies. We suggest that Mysticete migration should be thought of as a continuum of different strategies that have evolved in the face of different selective pressures. Instead of representing an exception to the rule, the resident Mediterranean fin whales may in fact fall towards one end of a larger spectrum of migratory behaviours. Agreater knowledge of ecological factors, reproductive patterns, and local adaptations will be needed to understand the evolutionary mechanisms behind the diversity of migratory habits.
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| 7. |
- Lawson, Julia M., et al.
(författare)
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Sympathy for the devil : a conservation strategy for devil and manta rays
- 2017
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Ingår i: PeerJ. - : PeerJ. - 2167-8359. ; 5
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Tidskriftsartikel (refereegranskat)abstract
- Background. International trade for luxury products, medicines, and tonics poses a threat to both terrestrial and marine wildlife. The demand for and consumption of gill plates (known as Peng Yu Sai, "Fish Gill of Mobulid Ray") from devil and manta rays (subfamily Mobulinae, collectively referred to as mobulids) poses a significant threat to these marine fishes because of their extremely low productivity. The demand for these gill plates has driven an international trade supplied by largely unmonitored and unregulated catches from target, and incidental fisheries around the world. Scientific research, conservation campaigns, and legal protections for devil rays have lagged behind those for manta rays despite similar threats across all mobufids. Methods. To investigate the difference in attention given to devil rays and manta rays, we examined trends in the scientific literature and updated species distribution maps for all mobufids. Using available information on target and incidental fisheries, and gathering information on fishing and trade regulations (at international, national, and territorial levels), we examined how threats and protective measures overlap with species distribution. We then used a species conservation planning approach to develop the Global Devil and Manta Ray Conservation Strategy, specifying a vision, goals, objectives, and actions to advance the knowledge and protection of both devil and manta rays. Results and Discussion. Our literature review revealed that there had been nearly 2.5-times more "manta"-titled publications, than "mobula" or "devil ray"-titled publications over the Past 4.5 years (January 2012 June 2016). The majority of these recent publications were reports on occurrence of mobulid species. These publications contributed to updated Area of Occupancy and Extent of Occurrence maps which showed expanded distributions for most mobulid species and overlap between the two genera. While several international protections have recently expanded to include all mobulids, there remains a greater number of national, state, and territory-level protections for manta rays compared to devil rays. We hypothesize that there are fewer scientific publications and regulatory protections for devil rays due primarily to perceptions of charisma that favour manta rays. We suggest that the well-established species conservation framework used here offers an objective solution to close this gap. To advance the goals of the conservation strategy we highlight opportunities for parity in protection and suggest solutions to help reduce target and by catch fisheries.
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| 8. |
- Stewart, Joshua D., et al.
(författare)
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Research Priorities to Support Effective Manta and Devil Ray Conservation
- 2018
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Ingår i: Frontiers in Marine Science. - : Frontiers Media S.A.. - 2296-7745. ; 5, s. 1-27
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Forskningsöversikt (refereegranskat)abstract
- 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.
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