The biology and ecology of the Pacific sharpnose shark Rhizoprionodon longurio

Abstract

Amidst global declines in elasmobranch populations resulting predominantly from overfishing, the need to gather data regarding shark ecology is greater than ever. Many species remain data deficient or at risk of going extinct before sufficient conservation measures can be applied. In this review, we summarise existing knowledge regarding the biology and ecology of the Pacific sharpnose shark Rhizoprionodon longurio (Jordan & Hilbert, 1882), a small‐bodied carcharhinid shark found in coastal waters of the Eastern Tropical Pacific Ocean that is of both commercial and ecological importance. We compare ecological parameters of this species with its closest extant relatives and identify major knowledge gaps and avenues for future research. In particular, additional studies investigating the behavioural and sensory ecology, as well as potential migratory patterns of the species are needed. Such studies will not only improve our understanding of R. longurio, but provide insight into the extent to which the numerous studies performed on a close relative—Rhizoprionodon terraenovae—provide an accurate representation of the biology and ecology of Rhizoprionodon and carcharhinids more generally.

Ontogenetic shifts in body form in the bull shark Carcharhinus leucas

“…The reasons for this discrepancy are unclear, although it is possible that juvenile bull sharks simply remain in their shallow nearshore environments longer than these other species. Furthermore, there is little evidence to suggest usage of nursery areas to the same extent as C. leucas in either S. lewini or R. longurio (Gayford & Whitehead, 2023; Heupel et al, 2007). Alternatively, juvenile bull sharks may be subjected to greater predation pressure than juveniles of either S. lewini or R. longurio .…”