Drones have become increasingly popular tools to study marine megafauna but are underutilized in batoid research. We used drones to collect video data of manta ray (Mobula cf. birostris) swimming and assessed behavior-specific kinematics in Kinovea, a semi-automated point-tracking software. We describe a ‘resting’ behavior of mantas making use of strong currents in man-made inlets in addition to known ‘traveling’ and ‘feeding’ behaviors. No significant differences were found between the swimming speed of traveling and feeding behaviors, although feeding mantas had a significantly higher wingbeat frequency than traveling mantas. Resting mantas swam at a significantly slower speed and wingbeat frequency, suggesting that they were continuously swimming with the minimum effort required to maintain position and buoyancy. Swimming speed and wingbeat frequency of traveling and feeding behaviors overlapped, which could point to other factors such as prey availability and a transitional behavior, influencing how manta rays swim. These baseline swimming kinematic data have valuable applications to other emerging technologies in manta ray research.

The sicklefin devil ray (Mobula tarapacana) is a large, pelagic ray which is listed as Endangered by the International Union for Conservation of Nature (IUCN). Mobula tarapacana is thought to have a circumglobal, yet patchy distribution, and has not been verified extant off the eastern USA. Here, we report 180 sightings of M. tarapacana with a total of 361 individuals, collated across five datasets from aerial survey operations and incidental sightings in the waters off the US East Coast and Gulf of Mexico, between 1996 and 2022. This study extends the northern range of M. tarapacana in the Gulf of Mexico to 29°N, and in the Atlantic to 40°N. Seasonal trends were observed off the north-eastern coast of the USA, with M. tarapacana only present in the summer months. Measurements from high resolution digital aerial imagery found M. tarapacana off the New York coast to be adults and subadults with an average disc width of 268 cm (±25, range 232–316 cm). This study provides important spatial and temporal data for management, as well as informing areas for future research on M. tarapacana in the western Atlantic.

Symbioses between remoras (Family Echeneidae) and marine megafauna are well‐documented across diverse lineages. However, despite recent advancements in understanding the intricacies of these interactions, the dynamics of these relationships remain poorly understood, largely due to the highly mobile nature of both host and symbiont. Here we report seven observations of Echeneidae cloacal diving behavior in manta rays. These observations span all three currently described species of manta rays ( Mobula yarae, Mobula birostris , and Mobula alfredi ), demonstrate that large Echeneidae can perform cloacal diving behavior in both juvenile and adult manta rays, and show that this behavior occurs across multiple ocean basins. We also document one observation of Echeneidae attachment beneath a host's gill slit and several occurrences of gill injuries consistent with Echeneidae intrusion. These observations contribute to the growing database of Echeneidae‐host behavioral interactions and provide an important foundation for understanding the extent, diversity, and dynamics underlying these highly debated, cryptic megafauna‐symbiont interactions in marine environments. By providing new evidence of the complexity of symbiotic relationships in marine environments, this study also offers a multi‐species natural history context that may inform future research and conservation considerations.