BackgroundInternational 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 mobulids.MethodsTo 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 mobulids. 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 DiscussionOur 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 bycatch fisheries.

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30Background. Increased interest in luxury products and Traditional Chinese Medicine, associated 31 with economic growth in China, has been linked to depletion of both terrestrial and marine 32 wildlife. Among the most rapidly emerging concerns with respect to these markets is the 33 relatively new demand for gill plates, or Peng Yu Sai ("Fish Gills"), from devil and manta rays 34 (subfamily Mobulinae). The high value of gill plates drives international trade supplied by largely 35 unmonitored and unregulated bycatch and target fisheries around the world. Devil and manta rays 36 are especially sensitive to overexploitation because of their exceptionally low productivity 37(maximum intrinsic rate of population increase). Scientific research, conservation campaigns, as 38 well as international and national protections that restrict fishing or trade have increased in recent 39 years. Many key protections, however, apply only to manta rays. 40Methods. We review the state of the development of scientific knowledge and capacity for these 41 species, and summarise the geographic ranges, fisheries and national and international protections 42 for these species. We use a conservation planning approach to develop the Global Devil and 43Manta Ray Conservation Strategy, specifying a vision, goals, objectives, and actions to advance 44 the conservation of both devil and manta rays. 45Results and Discussion. Generally, there is greater scientific attention and conservation focused 46on Manta compared to Devil Rays. We discuss how the successes in manta ray conservation can 47 be expanded to benefit devil rays. We also examine solutions for the two leading threats to both 48 devil and manta rays -bycatch and target fisheries. First, we examine how can the impact of 49 bycatch fisheries can be reduced through international measures and best-practice handling 50techniques. Second, we examine the role that responsible trade and demand can play in reducing 51 target fisheries for gill plates. Our paper suggests that given similarities in sensitivity and 52 appearance, particularly of the dried gill plate product, conservation measures may need to be 53 harmonised particularly for the larger species in this subfamily.

In French Polynesia, both currently recognized manta ray species, Mobula alfredi and M. birostris, are observed. Despite being an important cultural asset and generating significant economic benefits through manta ray watching tourism, published data on the ecology and threats to these species in the region are scarce. Based on an 18-year dataset of sighting records collected by citizen scientists and during two scientific expeditions, this study provides the first insights into the population characteristics and regional distribution of the two manta ray species in French Polynesia. A total of 1347 manta ray photographs (1337 for M. alfredi and 10 for M. birostris) were examined for the period January 2001-December 2017, with photo-identification techniques leading to the successful identification of 317 individual M. alfredi and 10 individual M. birostris throughout the Society, Tuamotu and Marquesas Islands. We provide the first confirmation of sympatric distribution of both species in the Society Islands. Our results highlight strong and long-term site fidelity of M. alfredi individuals to certain aggregation sites (> 9 years for 16 individuals) and reveal some degree of connectivity between populations, with 10 individuals recorded moving between islands located up to 50 km apart. Analysis of photographs of individuals bearing sub-lethal injuries (n = 68) suggests that M. alfredi are more likely to be injured at inhabited islands (Maupiti or Bora Bora; 75% of all injured individuals) than at uninhabited islands, with 75% of injuries related to boat propeller strikes and fishing gear entanglements. Our findings emphasize the need for further research to allow for a comprehensive evaluation of population structure, size and threats to manta rays in this region.