The giant oceanic manta ray Mobula birostris was listed in the US Endangered Species Act as a threatened species in 2018, yet insufficient data exist on manta populations throughout US waters to designate critical habitat. Taxonomic and genetic evidence suggests that manta rays in the Western Atlantic are a separate species (M. cf. birostris) and little is understood about the ecology and life history of this putative species. The juvenile life stage of both M. birostris and M. cf. birostris is particularly understudied. Here, we are the first to describe the characteristics of a manta ray population along a highly developed coastline in southeastern Florida using boat-based surveys and photo identification of individuals. Fifty-nine manta individuals were identified between 2016 and 2019. All males were sexually immature based on clasper development, and 96% of females were classified as immature based on size and absence of mating scars or visible pregnancies. Twenty-five (42%) individuals were observed more than once during the study period and 8 individuals were sighted over multiple years. The occurrence of juveniles, high site fidelity and extended use of the study area by juvenile manta rays suggest that southeastern Florida may serve as a nursery habitat. High occurrence of fishing line entanglement (27% of individuals) and vessel strike injury were documented, and rapid wound healing was observed. Future research and conservation efforts will focus on identifying the physical and biological features of the potential nursery habitat and on mitigation of anthropogenic impacts.

In 2018, the giant manta ray was listed as threatened under the U.S. Endangered Species Act. We integrated decades of sightings and survey effort data from multiple sources in a comprehensive species distribution modeling (SDM) framework to evaluate the distribution of giant manta rays off the eastern United States, including the Gulf of Mexico. Manta rays were most commonly detected at productive nearshore and shelf-edge upwelling zones at surface thermal frontal boundaries within a temperature range of approximately 20–30 °C. SDMs predicted highest nearshore occurrence off northeastern Florida during April, with the distribution extending northward along the shelf-edge as temperatures warm, leading to higher occurrences north of Cape Hatteras, North Carolina from June to October, and then south of Savannah, Georgia from November to March as temperatures cool. In the Gulf of Mexico, the highest nearshore occurrence was predicted around the Mississippi River delta from April to June and again from October to November. SDM predictions will allow resource managers to more effectively protect manta rays from fisheries bycatch, boat strikes, oil and gas activities, contaminants and pollutants, and other threats.

South Florida has a significant number of recreational anglers, and some shore‐based fishing sites overlap with habitat for juvenile manta rays. Although manta rays are prohibited from harvest in Florida, they are frequently seen foul‐hooked or entangled in fishing line. Recreational anglers (n = 198) were surveyed at piers and inlet jetties in Palm Beach County, Florida, USA to assess their knowledge of and actions and attitudes towards manta rays. Analysis of the responses revealed that while most anglers could identify a manta ray (66.7%) and expressed no interest in casting at (93.4%) or catching a manta ray (95.5%), they lacked knowledge about threats to mantas, as well as their conservation and protected status. Surveyed anglers overwhelmingly supported manta ray conservation (82.3%) and environmental protection (98.0%). Results indicate pier and inlet anglers are not using tackle strong enough to land a large ray to remove fishing gear, therefore it is recommended that outreach focuses on preventing recreational fishery interactions with manta rays, encouraging use of environmentally friendly tackle, and fostering engagement with anglers as citizen scientists. These results can inform the design of outreach materials aimed at closing knowledge gaps and encouraging best practices. Positive attitudes towards the environment and existing neutral behaviours towards manta rays indicate an opportunity to shift the behaviour of shore‐based anglers in this area in support of manta ray conservation.

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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.

Cetacean mixed-species groups are common around the world, but little is known about how and why they occur. Tursiops truncatus (Common Bottlenose Dolphin) and Stenella frontalis (Atlantic Spotted Dolphin) are delphinidae species that have been sighted, separately, along the southeast coast of Florida. Although these species are observed interacting together in other portions of their range, this is the first report of a known mixed-species group of Atlantic Spotted Dolphins and Common Bottlenose Dolphins off the southeast Florida coast. We observed both foraging and social behaviors using a DJI Mavic Pro 2 drone. The function of mixed-species groups is understudied, yet Florida may provide opportunities for future research.

Merosin deficient congenital muscular dystrophy (MDC1A) is a fatal, autosomal recessive disease caused by laminin α2 chain deficiency, preventing formation of the extracellular matrix protein laminin 211. Afflicted children experience profound muscle weakness and degeneration and often die prematurely from failure to thrive or acute respiratory failure resulting from weak respiratory muscles and progressive scoliosis. While diseased skeletal muscle has been well characterized, airway smooth muscle (ASM) has not been investigated and respiratory failure has been attributed solely to diaphragmatic weakness. Therefore, as a first step we investigated the contractile properties of ASM isolated from DyW mice, an animal model of MDC1A.Primary bronchial rings from 7wk WT and DyW mice were harvested and cleaned. Rings were mounted on wire triangles in a bath with oxygenated Krebs solution and connected to a force transducer to measure contractile responses to depolarizing 51mM KCl Krebs solution and 10‐5 M carbachol to activate G‐protein coupled muscarinic receptors. Rings were quick frozen and saved for histological analysis. Transverse sections (7 µm thick) were stained with Gomori Trichrome to differentiate ASM. Bronchial ASM cross sectional area (CSA) was calculated using NIS Basic Research software. Contractile forces were normalized to ASM CSA to determine ASM stress.The stress responses of DyW bronchi are significantly higher than WT in response to both 51 mM KCl (nWT=7, nDyW=3, p<0.002) and 10‐5 M carbachol (nWT =8, nDyW =4, p<0.006). These data indicate that ASM isolated from DyW mice are significantly hypercontractile compared to their WT counterpart, and could potentially contribute to respiratory insufficiency in MDC1A.