Enhancing Conservation of the Whitespotted Eagle Ray (Aetobatus narinari) in Cozumel: Integrating Acoustic Telemetry and Mobile-Enhanced Citizen Science for Improved Spatial Ecology Insights

The study in focus aimed to assess the philopatric and residency patterns of whitespotted eagle rays (Aetobatus narinari) on a local scale in Cozumel, Mexico. The species is listed as endangered on the IUCN Red List due to incidental and targeted fishing, limited suitable habitat and a decline in mature individuals. However, effective management and conservation strategies must be grounded in a clear understanding of its spatial ecology and habitat use. Conducted by Cozumel Ocean Research (COR) in collaboration with citizen scientists, the research utilised photo-identification and the I3S Spot software to identify and track individual rays. Between November 2014 and July 2023, data was opportunistically collected across 62 dive sites in Cozumel by COR members and citizen scientists, noting observations such as the sex, approximate size, activity/behaviour, depth of sighting, sighting location and dive site for each ray (Beber et al., 2024).

Key goals of the study included mapping key zones for foraging and aggregation, evaluating philopatric tendencies and validating the role of citizen science programs in data collection. Eventually, the insights gained would be able to contribute to the broader understanding of A.narinari and support the development of conservation policies for the rays in the Caribbean.

Citizen science programs played a crucial role in the overall success of the study, with 31.24% of rays originally identified through submissions from citizen scientists. Such efforts have enabled increased research efforts across large temporal and spatial scales, reducing the cost of data collection while supporting local tourism and contributing to public education.

The Spotted Eagle Ray Citizen Science Program trained dive professionals and citizen scientists to collect accurate data on the rays. Despite this, significant limitations in the study included inconsistent reporting and engagement, missing data fields and blurry or distant photo and video submissions, which rendered many entries unusable. Consequently, approximately 70-75% of the sightings reported in the citizen science database were not viable for Photo-ID analyses and had to be excluded. Additionally, biased sampling efforts were noted, as data collection predominantly occurred at frequently visited dive and snorkel sites, located in the western regions of Cozumel.

Photo-ID was recognised as a cost-effective and non-invasive method for studying marine megafauna. The complex white dorsal markings, unique to each individual ray, made photo ID an ideal technique for identification. Additionally, its accessibility to the public made it a valuable tool for citizen science, facilitating the collection of baseline data on these rays. The I3S Spot software, a computer-aided photo ID application that utilizes natural markings to identify individual animals, has also been used in previous studies, demonstrating its reliability for this research. However, while the I3S Spot software was effective in identifying the rays, it was extremely time consuming as manual cropping was required for the matching algorithm to identify the individual.

A central challenge highlighted in the study is the limited understanding of the full spatial ecology and movement patterns of A.narinari around Cozumel, largely due to a sampling bias concentrated on the island’s western coast. While aggregation and foraging zones have been identified, significant data gaps remain – particularly in the island’s extreme north, where mangrove areas and coastal lagoons, likely critical for pupping and nursery activities, are still poorly studied. This lack of data hinders a comprehensive understanding of the species' reproductive ecology and limits the effectiveness of conservation efforts.

To complement ongoing research focused on Cozumel’s western coast, adopting a dual approach that integrates technology-driven methods, such as acoustic telemetry, with mobile-enhanced citizen science is recommended. This combined strategy builds upon established knowledge of aggregation and foraging zones and leverages current citizen science practices. Crucially, it seeks to address key limitations identified in the study – the underrepresentation of data from the eastern and northern coasts, largely due to stronger currents and restricted port infrastructure and a sampling bias concentrated on the tourist-heavy western coast. By cross-validating between telemetry and citizen submitted observations, this approach aims to enhance both the spatial coverage and data quality of research A.narinari’s movements and habitat use.

Acoustic telemetry is a widely used marine tracking technology that involves attaching ultrasonic transmitters to animals and deploying stationary receivers in the water to detect and store received signals. This approach enables researchers to study the behaviour, movement patterns and even physiological responses of free-roaming animals in detail (Hellström et al., 2022). In the context of Cozumel, deploying an array of acoustic receivers at strategically selected locations would help address existing spatial data gaps and provide continuous, high-resolution movement data to enhance the understanding of A.narinari’s spatial ecology. Priority deployment areas include the island’s extreme north, where mangrove and coastal lagoon habitats may serve as critical pupping and nursery grounds; the eastern coast, which remains under-sampled due to limited dive access; known aggregation and foraging sites to monitor site fidelity; and movement corridors between aggregation and foraging zones to uncover broader spatial connectivity.

Studies by DeGroot et al. (2020) used acoustic telemetry to track A.narinari in Florida, revealing that the rays preferred areas with high human activity, moved more during warmer periods and shifted between deeper waters by day and shallower areas at night – findings that have contributed to informing statewide conservation planning for the species.

Modern acoustic telemetry systems offer several practical advantages – they require minimal maintenance and support long-term autonomous data collection, with some receiver networks lasting up to a decade. When combined with environmental sensors that can monitor parameters such as temperature, depth and water quality, these systems provide a powerful tool for studying the fine-scale behaviour and habitat use of aquatic species (Hellström et al., 2022). Compared to satellite telemetry, acoustic telemetry is more cost-effective (Hardin et al., 2024) and is particularly well-suited for Cozumel due to its localised focus, providing high-resolution, site-specific data that is essential for understanding A.narinari's spatial ecology in nearshore and reef environments (Hardin et al., 2024). Unlike Photo-ID, which relies on opportunistic sightings, acoustic telemetry will be able to provide continuous and high-resolution data of tagged individuals.

However, COR and potential volunteers need to follow tagging protocols specifically designed for A.narinari, particularly because the transmitters require surgical implantation. Adhering to proper tagging procedures is critical to minimise stress and reduce the risk of injury or long-term harm to the rays. In addition, technological limitations such as transmitter or receiver failure, as well as poor receiver array design, can compromise data quality. This can result in detection gaps and spatial blind spots that hinder accurate movement tracking and behavioural analysis. Furthermore, the high upfront capital costs and network-related fees associated with acoustic telemetry – often amounting to several thousand USD – pose a significant barrier, particularly for large-scale or long-term deployments (Hardin et al., 2024).

Currently, COR’s Report a Ray initiative requires citizen scientists to manually input individual sighting data through a web-based form (Figure 1). This process can be cumbersome, particularly for casual divers who may not have the time or familiarity with data entry protocols after their dives. The interface lacks user-friendly features, which makes the submission process feel tedious and discourages consistent participation. Furthermore, the study highlights that many submissions are incomplete or contain low-quality images, such as blurry or distant photos and videos, which limit the ability to accurately identify individuals and conduct in-depth ecological analyses.

To improve the accessibility of the Report a Ray initiative, a mobile app could be developed with a strong emphasis on both engagement and data quality. For casual divers, the app could feature bite-sized and visually engaging instructions that simplify the reporting process and lower the barriers to entry. These prompts could be gamified or story-based to make the task feel less like paperwork and more expedition-like. For more experienced and frequent divers, the app could offer advanced features and certification pathways that promote proper logging techniques and best practices in citizen science reporting.

To ensure high-quality data collection, the app could incorporate enhanced data quality control. Features such as offline data entry, automated GPS tagging, date and time stamping and smart prompts could guide users to complete all essential fields before submission. Additional tools, such as photo quality guidelines and real-time feedback, would further improve the reliability and usefulness of visual data. A simplified interface, paired with functionality for batch uploads by dive operators, would also streamline reporting and make the system more appealing for both recreational and professional users.

Beyond usability, building a strong incentive structure is key to sustaining engagement. Digital badges, leaderboard rankings and ambassador statuses are low-hanging fruits that can be incorporated to recognise dive operators or divers who consistently submit high-quality data. Regular updates on how the data is being used for conservation – paired with community events or virtual meetups – would also help build a sense of shared purpose.

To complement the ongoing acoustic telemetry efforts, the role of committed citizen scientists could also extend beyond data collection. Trained divers and dive operators could assist in deploying acoustic receivers, conducting routine maintenance or supporting manual data retrieval from submerged units. This not only strengthens the link between citizen science and formal research but also deepens stakeholder investment in the long-term conservation of A.narinari and its habitat around Cozumel.