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.

Localised population declines and increased pressure from fisheries have prompted the promotion of manta ray interaction tourism as a non-consumptive, yet economically attractive, alternative to the unsustainable harvesting of these animals. Unfortunately, however, wildlife tourism activities have the potential to adversely impact focal species. In order to be sustainable, operations must be managed to mitigate negative impacts. A preliminary assessment of reef manta ray, Manta alfredi, behaviour identified short-term behavioural responses during a third of tourism interactions in the Ningaloo Marine Park, Western Australia. Although it remains unknown whether these responses translate to biologically significant impacts on the population as a whole, it is proposed that the precautionary principle be used to guide management intervention in the absence of conclusive evidence of the magnitude of tourism impacts. The principle supports the implementation of precautionary strategies to protect species and their environment from harm, even when the extent of the harm is yet to be confirmed. An increase in the level of industry management is recommended, including the implementation of a licensing system and adherence of all operators to a mandatory code of conduct during manta ray interactions. Considering the well designed and precautionary-driven management program of the Ningaloo whale shark tourism industry operating within the same marine park, a management program with the same underlying principles and objectives is deemed to be an ideal framework to build a comprehensive management plan for the manta ray interaction industry.

Highly mobile marine megafauna species, while widely distributed and frequently threatened, often aggregate in distinct localized habitats. Implementation of local management initiatives within these hotspots is more achievable than developing effective conservation strategies that encompass their entire distributions. Such measures have the potential for disproportionate population-level benefits but rely on a detailed understanding of spatiotemporal habitat use. To that end, we examined the residency and small-scale habitat use of 51 whale sharks (Rhincodon typus) over 5 years at an aggregation site in Tanzania using passive acoustic telemetry. Whale sharks were highly resident within and across years, with a combined maximum residency index of 0.39. Although fewer sharks were detected from March to September, residency was high throughout the year. Ancillary photographic-identification data showed that individual residency persisted before and after tag attachment. Kernel utilization distributions (KUD) and movement networks both revealed the same spatiotemporal pattern of habitat use, with a small core habitat (50% KUD area for all sharks combined = 12.99 km²) that predictably changed on a seasonal basis. Activity spaces did not differ with time of day, sex, or size of the sharks, indicating a population-level pattern driven by prey availability. The small and predictable core habitat area at this site means that site-based management options to reduce shark injuries and mortality from boat strike and fishing gear entanglement can be spatially targeted for maximum effectiveness and compliance by human users.

Manta rays are internationally threatened species and population declines have been reported in various locations worldwide. As iconic megafauna species, they are also major drawcards for wildlife tourism industries. Economic valuation of these industries can provide an incentive for the protection of species and natural habitats through the creation of marine protected areas (MPAs) and the restriction of harvesting or trade. Site-specific estimates are essential, particularly in developing countries, to promote the nonconsumptive use of resources and develop appropriate management strategies. This study represents the first localized estimate of the economic benefits of manta ray tourism in Mozambique. Data from 478 tourist expenditure surveys, 15 stakeholder surveys, and yearly diver numbers provided by coastal tour operators were used to estimate the economic impact of manta ray tourism in the Inhambane Province. Manta ray–focused tours were estimated to be worth US$10.9 million per year in direct revenue to dive operators in the Inhambane Province, with an estimated direct economic impact (including associated tourism expenditures) of US$34.0 million annually. In the absence of manta ray tourism, between $16.1 million and $25.7 million would be lost to the region each year. Tourist and stakeholder survey responses emphasized the importance of manta rays to Mozambican coastal tourism. Both parties highlighted the need for increased protection of marine species and their environment and showed strong support for the implementation of MPAs along the Inhambane coast.