Citizen science sheds light on the cryptic ornate eagle ray Aetomylaeus vespertilio

Abstract

1. The ornate eagle ray Aetomylaeus vespertilio (Bleeker, 1852) is a rare and Endangered species of eagle ray, with a patchy distribution across the Indo-West Pacific region, for which data are scarce. 2. Citizen science-sourced data from online social media platforms were used to shed light on the distribution and ecology of the ornate eagle ray. 3. A total of 53 reports of A. vespertilio were found on Facebook, Instagram, Twitter, and YouTube, including four reports of dead specimens. All live reports occurred in shallow reef or lagoon ecosystems. Two individual A. vespertilio specimens were re-sighted in the same general area following initial identification within 9 and 13 months at Ningaloo Reef and at Lady Elliot Island, Australia, respectively, as confirmed through their dorsal spot patterns. One report was at Richard's Bay in South Africa, the southernmost known location for this species in the Indian Ocean (28°S). Live reports were also reported from the Maldives, the Seychelles, Egypt (Red Sea), Philippines, Palau, and elsewhere on the Great Barrier Reef, Australia. 4. Results indicate that citizen-collected data can shed light on the occurrence and distribution of cryptic species, as well as complement monitoring programmes.

First records of the ornate eagle ray Aetomylaeus vespertilio from the Inhambane Province, Mozambique

“…(2016) for confirmation. While dorsal spot patterns on the pelvic and pectoral fins have been used to distinguish between A. vespertilio individuals (Araujo et al ., 2020), the photo of the first sighting was not of sufficient quality to assess whether the two sightings were of a single individual, or multiple individuals.

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“…Few records exist from fisheries (e.g. Paul, 2011; Benjamin et al ., 2012), and live sightings are limited, with a recent study using social media searches and citizen science contributions to add 53 photo-documented sightings of the species to existing records (Araujo et al ., 2020). Given the extreme rarity of sightings, additional records are particularly valuable for these threatened and elusive rays in order to expand knowledge of their distribution, especially from locations where the species is yet to be documented.…”

“…Aetomylaeus vespertilio is a pelagic ray, occurring in coastal waters to depths of at least 110 m in tropical and sub-tropical regions of the Indo-Pacific, and is commonly sighted over coral reefs and sand/mud flats (Last et al ., 2016; White & Kyne, 2016). The known distribution is patchy and spans from eastern Australia through southern China, Indonesia, Palau, the Philippines, Malaysia, India, the Maldives and Seychelles archipelagos, to the Red Sea (White & Kyne, 2016; Araujo et al ., 2020). In southern Africa, a single report exists from Richard's Bay, South Africa where an individual was caught by a sports angler in 2018 and released alive (Araujo et al ., 2020; Ebert et al ., 2021).…”

“…The known distribution is patchy and spans from eastern Australia through southern China, Indonesia, Palau, the Philippines, Malaysia, India, the Maldives and Seychelles archipelagos, to the Red Sea (White & Kyne, 2016; Araujo et al ., 2020). In southern Africa, a single report exists from Richard's Bay, South Africa where an individual was caught by a sports angler in 2018 and released alive (Araujo et al ., 2020; Ebert et al ., 2021). The species is documented to occur in Mozambique (Last et al ., 2016; White & Kyne, 2016; Araujo et al ., 2020) and was acknowledged to exist in Mozambican coastal waters by Warnell et al .…”

“…In southern Africa, a single report exists from Richard's Bay, South Africa where an individual was caught by a sports angler in 2018 and released alive (Araujo et al ., 2020; Ebert et al ., 2021). The species is documented to occur in Mozambique (Last et al ., 2016; White & Kyne, 2016; Araujo et al ., 2020) and was acknowledged to exist in Mozambican coastal waters by Warnell et al . (2014), however we were unable to trace a specific report to confirm the exact location and nature of the sighting(s).…”