Linking local movement and molecular analysis to explore philopatry and population connectivity of the southern stingray Hypanus americanus

Abstract

Limited data pertaining to life history and population connectivity of the datadeficient southern stingray (Hypanus americanus) are available. To determine potential vulnerabilities of their populations, this study aimed to analyse their movement patterns and genetic variability. A population of southern stingrays encompassing nine sites around Cape Eleuthera, the Bahamas, has been monitored using markrecapture, spanning a 2.5 year period. Out of 200 individual stingrays, more than a third were encountered again. The home range of the females appears to be restricted, which supports the notion of high site residency. As resident populations of stingrays could suffer from a lack of population connectivity and be predestined for genetic isolation and local extirpation, this study further investigated the genetic connectivity of four sample sites in the central and western Bahamas. A haplotype analysis from the mitochondrial D-loop region showed that no distinct population structure strictly correlated with the sample site. These findings were complemented by five microsatellite loci that revealed high degrees in genotypic variability and little population differentiation. The results suggest gene flow mediated by both males and females.

Habitat use and nursery evaluation for the longnose stingray Hypanus guttatus (Bloch & Schneider, 1801) using vertebral microchemistry

“…H. guttatus does not seem to fit several of these criteria due to a potentially asynchronous reproductive cycle (Tagliafico et al, 2013), and the possible lack of extensive movements based on other Hypanus species (Schwanck et al, 2020;Tilley et al, 2013) and our habitat use data. Therefore, H. guttatus probably follows the habitat use patterns of coastal sharks described by Knip et al (2010), with individuals fulfilling their whole life cycle in a relatively small area.…”

Insights into genetic variation and demographic history of sharpnose rays: examinations of three species of Telatrygon (Elasmobranchii, Dasyatidae) from the Indo‐West Pacific

“…2019), and southern stingray ( Hypanus americanus ) (Schwanck et al . 2020). The rays generally exhibit K‐selected life history characteristics such as longevity, long gestation periods, large ova, and aplacental viviparity (Last et al .…”

“…Dispersal behavior in elasmobranchs (sharks and skates and rays) have revealed a putative pattern of male-biased dispersal in many sharks (reviewed in Chapman et al 2015), but it is rarely reported in rays. It has only been reported in spotted eagle ray (A. narinari) (Sellas et al 2015), short-tail stingray (Bathytoshia brevicaudata) (Roycroft et al 2019), and southern stingray (Hypanus americanus) (Schwanck et al 2020). The rays generally exhibit K-selected life history characteristics such as longevity, long gestation periods, large ova, and aplacental viviparity (Last et al 2016a).…”

Site fidelity is not revealed by genetic markers in stingrays

“…The utility of conservation management tools, such as marine protected areas, is rarely based on an informed knowledge of the life-history characteristics of the species for which such conservation measures are intended (Stewart et al, 2009). Tanja Schwanck and colleagues (Schwanck et al, 2020) undertook an elegant study in which they The study not only highlights the challenge to align relevant timescales regarding behavioural patterns inferred from contemporary tagging studies with genetic patterns which may evolve over timescales of millennia; it also emphasizes the difficulty in trying to understand the highly diverse behavioural patterns throughout the life-history of marine animals. Although the reported genetic diversity is good news for the southern stingray, the study showcases how difficult the design of effective and efficient management would be.…”

“…The utility of conservation management tools, such as marine protected areas, is rarely based on an informed knowledge of the life‐history characteristics of the species for which such conservation measures are intended (Stewart et al ., 2009). Tanja Schwanck and colleagues (Schwanck et al ., 2020) undertook an elegant study in which they combined 30 months of mark‐recapture data with genetic techniques to understand patterns of movement and connectivity in a population of southern stingray (Hypanus americanus, Hildebrand & Schroeder, 1928). They tagged and sampled 200 sub‐adult and adult stingrays from nine sites around Cape Eleuthera in The Bahamas.…”