Courtship and Reproduction of the Whitetip Reef Shark <i>Triaenodon obesus</i> (Carcharhiniformes: Carcharhinidae) in an Ex Situ Environment, with a Description of the Late Embryonic Developmental Stage

Elasmobranchs represent a group of species under considerable anthropic pressure because of the scale of industrial and artisanal fisheries and the loss of essential areas for nursery and feeding, which are causing substantial population losses around the world. Reproduction in an ex situ environmen...

Full description

Bibliographic Details
Main Authors: Sérgio Ricardo Santos, Veronica Takatsuka, Shayra P. Bonatelli, Nicole L. L. Amaral, Matheus F. Goés, Rafael F. Valle
Format: Article
Language:English
Published: MDPI AG 2022-11-01
Series:Animals
Subjects:
Online Access:https://www.mdpi.com/2076-2615/12/23/3291
Description
Summary:Elasmobranchs represent a group of species under considerable anthropic pressure because of the scale of industrial and artisanal fisheries and the loss of essential areas for nursery and feeding, which are causing substantial population losses around the world. Reproduction in an ex situ environment enables a healthy population to be built and maintained in networks of public aquariums, increasing our knowledge of elasmobranch reproductive biology and offering the opportunity for reintroductions in areas where native populations have been removed. The study reports two successful pregnancies of the whitetip reef shark <i>Triaenodon obesus</i>, considered a vulnerable species by the International Union for the Conservation of Nature. Copulation and gestation data are provided, including ultrasound recordings of the late stage of embryo development. Ultrasonography was performed with the GE Logiq and convex transducer and revealed a fetus with defined fins and organogenesis, with definition of eyes, gills, liver, a heart with individualized chambers, partially defined kidneys, and a well-defined spiral intestine. A cartilaginous skeleton forming a posterior acoustic shadow was detailed, as well as a moving fetus with a biparietal diameter of 6.47 cm and a heart rate of 62 Beats Per Minute on spectral Doppler. This is the first successful reproduction of <i>T. obesus</i> in an aquarium in Brazil.
ISSN:2076-2615