Migratory connectivity and philopatry of cownose rays Rhinoptera bonasus along the Atlantic coast, USA

Abstract

25Migratory species link spatially separated ecosystems, and understanding their migrations is 26 critical for conservation and management. The cownose ray Rhinoptera bonasus is a large-27 bodied batoid ray implicated in shellfish declines along the US Atlantic coast, but its migrations 28 and habitat use remain poorly understood. We used passive acoustic telemetry to track tagged 29 adult female (N = 30) and male (N = 12) rays released during summer and fall 2014-2016 in 30 Maryland, Virginia, and Georgia. Twenty-three tags provided data for more than one year. 31Individuals from all tagging locations overwintered in the same region offshore of Cape 32 Canaveral, Florida, then returned in summer to the estuaries where tagging took place. Hidden 33 Markov modeling identified three behavioral states (Resident, Ranging, Migratory), with ray 34 movements generally classified as non-migratory (Resident and Ranging behavioral states) in 35 summer and winter, and migratory (Migratory behavioral state) in spring and fall. Linear 36 discriminate analysis suggested strong philopatry to tagging locations. This study provides the 37 first full annual migration tracks for cownose rays along the US Atlantic coast, indicating that 38 they migrate between summer pupping and mating habitats in estuaries south of Long Island, 39 New York and shared overwintering habitats off the east coast of Florida near Cape Canaveral. 40 Our results highlight the value of national-scale networks of acoustic telemetry arrays for 41 identifying migratory patterns of highly mobile marine species.42 43 Cownose ray migration 3 66 Cownose ray migration 4 6-7 years with a maximum observed age of 18 years at a DW of 98 cm (Fisher et al. 2013).

Identifying Important Juvenile Dusky Shark Habitat in the Northwest Atlantic Ocean Using Acoustic Telemetry and Spatial Modeling

“…In the northwest Atlantic Ocean, temperature effects have been shown to more strongly impact species at higher trophic levels (Friedland et al 2019) and have the ability to dramatically influence features like the Middle Atlantic Bight Cold Pool (Lentz 2017) as well as influence distributions of coastal fishes (Secor et al 2019). There is already evidence that some elasmobranch species are expanding or shifting their distributions in response to changing ocean conditions (e.g., Bangley et al 2018b), and such shifts are likely in other migratory elasmobranchs in the U.S. mid‐Atlantic region (Haulsee et al 2018; Ogburn et al 2018). If thermal and productivity patterns are altered by climate change, Dusky Sharks are likely to shift their distributions poleward in response, as has been observed for other temperate mid‐Atlantic species (Nye et al 2009; Pinsky et al 2013).…”

Networked Animal Telemetry in the Northwest Atlantic and Caribbean Waters

“…This approach is useful in identifying habitat areas that may be worth further assessment as essential habitat. For example, Ogburn et al (2018) tracked Cownose Rays Rhinoptera bonasus migrating from summer habitats in the Chesapeake Bay and Savannah River to a shared overwintering habitat off Cape Canaveral, Florida, and they noted that the bay and river were the only locations along the migratory route within which tagged rays would slow their movements and spend extended periods of time. Although FIGURE 1.…”

“…Receiver deployments that were not entered into one of the connected regional databases are not shown. summer habitats have long been identified as or suspected to be nursery habitats for Cownose Rays (e.g., Smith and Merriner 1987), the aggregation site revealed off Cape Canaveral may also be worthy of further assessment as essential habitat (Ogburn et al 2018). Coastal-scale tracking using receiver networks also allowed Bangley et al (2020, this themed issue) to identify potential associations between juvenile Dusky Sharks Carcharhinus obscurus and areas where oceanographic features created seasonal temperature stratification.…”

“…Protection of these areas is the rationale behind spatial fishery management and conservation measures, such as seasonal time–area closures, gear‐restricted areas, and the establishment of marine protected areas (MPAs). Movement and habitat use behaviors vary among individuals in many marine species, but receiver networks enable sufficient data collection to account for individual variability (e.g., Ogburn et al 2018). Perhaps the most direct practical applications of large‐scale telemetry networks are to support planning, siting, and assessment of proposed or implemented spatial management measures.…”

Assigning Fates in Telemetry Studies Using Hidden Markov Models: an Application to Deepwater Groupers Released with Descender Devices

“…To date, the utility of HMMs in ecology has been primarily to expand biological knowledge via descriptive studies, although authors have also used HMMs for other purposes (e.g., McClintock et al 2020). In marine fisheries, HMMs have been applied in studies of spawning behaviors (Holan et al 2009), behavior in sharks (Papastamatiou et al 2018), migratory phases of Southern Bluefin Tuna Thunnus maccoyii (Patterson et al 2009) and Cownose Ray Rhinoptera bonasus (Ogburn et al 2018), movement types in Gray Triggerfish Balistes capriscus (Bacheler et al 2019), and behavioral states in Yellowfin Tuna T. albacares and Bigeye Tuna T. obesus (Vermard et al 2010). However, instead of identifying and classifying behaviors of the tagged animals, it is possible that HMMs could identify changes in movement patterns of the tags, which may in fact relate to different animals (e.g., a predator that has ingested a tag).…”