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Sharks can incur a range of external injuries throughout their lives that originate from various sources, but some of the most notable wounds in viviparous shark neonates are at the umbilicus. Umbilical wounds typically heal within 1 to 2 months post-parturition, depending on the species, and are therefore often used as an indicator of neonatal life stage or as a relative measure of age [e.g. grouping by umbilical wound classes (UWCs), according to the size of their umbilicus]. To improve comparisons of early-life characteristics between studies, species and across populations, studies using UWCs should integrate quantitative changes. To overcome this issue, we set out to quantify changes in umbilicus size of neonatal blacktip reef sharks (Carcharhinus melanopterus) around the island of Moorea, French Polynesia, based on temporal regression relationships of umbilicus size. Here, we provide a detailed description for the construction of similar quantitative umbilical wound classifications, and we subsequently validate the accuracy of our classification and discuss two examples to illustrate its efficacy, depletion rate of maternally provided energy reserves and estimation of parturition period. A significant decrease in body condition in neonatal sharks as early as twelve days post-parturition suggests a rapid depletion of in utero-allocated energy reserves stored in the liver. Back calculations of timing of birth based on the umbilicus size of neonates determine a parturition season from September to January, with most parturitions occurring during October and November. As such, this study contributes valuable data to inform the conservation and management of young-of-the-year blacktip reef sharks, and we therefore encourage the construction and use of similar regression relationships for other viviparous shark species. Live-bearing shark species are inherently born with an open wound, the umbilicus. The healing status of this umbilicus can be used to estimate the age of newborn sharks. This study proposes the first umbilical wound classification based on quantitative changes in umbilicus size allowing accurate age estimates of newborn sharks.

Supplemental material, sj-docx-1-jbr-10.1177_07487304221107843 for Diel Rhythm and Thermal Independence of Metabolic Rate in a Benthic Shark by Carolyn R. Wheeler, Jeff Kneebone, Dennis Heinrich, Jan M. Strugnell, John W. Mandelman and Jodie L. Rummer in Journal of Biological Rhythms

Accession numbers for the sAC sequences used for creating figure S1 (ESM). Sequences of ray-finned (Actinopterygii) are listed in the table and organized in taxonomic ranks. The other sequences are provided below the table. WGS= whole genome shotgun. MW= molecular weight. Sequences were obtained from NCBI (https://www.ncbi.nlm.nih.gov/) and The Ensembl project (http://www.ensembl.org/), supplemented by information found in (1–4). Fish taxonomy was based on (5)

It includes 6 figures, each with its own legend

Fish husbandry and immunostaining

Applying physiological tools, knowledge and concepts to understand conservation problems (i.e. conservation physiology) has become commonplace and confers an ability to understand mechanistic processes, develop predictive models and identify cause-and-effect relationships. Conservation physiology is making contributions to conservation solutions; the number of ‘success stories’ is growing, but there remain unexplored opportunities for which conservation physiology shows immense promise and has the potential to contribute to major advances in protecting and restoring biodiversity. Here, we consider how conservation physiology has evolved with a focus on reframing the discipline to be more inclusive and integrative. Using a ‘horizon scan’, we further explore ways in which conservation physiology can be more relevant to pressing conservation issues of today (e.g. addressing the Sustainable Development Goals; delivering science to support the UN Decade on Ecosystem Restoration), as well as more forward-looking to inform emerging issues and policies for tomorrow. Our horizon scan provides evidence that, as the discipline of conservation physiology continues to mature, it provides a wealth of opportunities to promote integration, inclusivity and forward-thinking goals that contribute to achieving conservation gains. To advance environmental management and ecosystem restoration, we need to ensure that the underlying science (such as that generated by conservation physiology) is relevant with accompanying messaging that is straightforward and accessible to end users.

Elasmobranchs are critical to tourism industries worldwide. In French Polynesia, where ecotourism is the second most important industry, little is known about the spatiotemporal distribution of eagle rays. This study represents the first investigation into habitat use and behaviour of ocellated eagle rays (Aetobatus ocellatus) in French Polynesia focused on two sites with different levels of anthropogenic noise. Environmental variables and biological data were recorded over a one-year period to explore the distribution patterns of 113 eagle rays identified at these sites. Results revealed distinct patterns in habitat use between the two sites, with the eagle ray population structured according to ontogenetic stage. Young rays preferred the site with lower levels of noise pollution, where they foraged at the end of the day. Adult eagle rays gathered in the mornings at the louder site, where the only noticeable activity was group swimming. Overall, our results could help conservation initiatives to manage this important species in French Polynesia, and potentially other coral reef areas, especially in the context of rising human impacts on the environment.

Meta-analysis methodology

Experimental protocols, statistical analyses, and results

This file contains supplementary information on larval rearing conditions, the experimental set-up for sediment resuspension, respirometry protocol, gill analysis, and additional results.

The Aetobatus species present in French Polynesian Islands is identified as A. ocellatus, the ocellated eagle ray. This finding is based on DNA barcoding and supports the recent splitting of Aetobatus narinari, the spotted eagle ray, into two distinct species. Ray samples were collected from the Tuamotu and the Society archipelagos in 2012. All samples have a similar haplotype, suggesting they are conspecific and are also genetically close to specimens collected from Australia and New Caledonia.

In aquaculture, growth and sex are economically important traits. To accelerate genetic improvement in increasing growth in salt-tolerant tilapia, we conducted QTL mapping for growth traits and sex with an F2 family, including 522 offspring and two parents. We used 144 polymorphic microsatellites evenly covering the genome of tilapia to genotype the family. QTL analyses were carried out using interval mapping for all individuals, males and females in the family, respectively. Using all individuals, three suggestive QTL for body weight, body length and body thickness respectively were detected in LG20, LG22 and LG12 and explained 2.4% to 3.1% of phenotypic variance (PV). When considering only males, five QTL for body weight were detected on five LGs, and explained 4.1 to 6.3% of PV. Using only females from the F2 family, three QTL for body weight were detected on LG1, LG6 and LG8, and explained 7.9–14.3% of PV. The QTL for body weight in males and females were located in different LGs, suggesting that in salt-tolerant tilapia, different set of genes ‘switches’ control the growth in males and females. QTL for sex were mapped on LG1 and LG22, indicating multigene sex determination in the salt-tolerant tilapia. This study provides new insights on the locations and effects of QTL for growth traits and sex, and sets the foundation for fine mapping for future marker-assisted selection for growth and sex in salt-tolerant tilapia aquaculture. NRF (Natl Research Foundation, S’pore) Published version