In a search for biomarkers of health in whale sharks and as exploration of metabolomics as a modern tool for understanding animal physiology, the metabolite composition of serum in six whale sharks (Rhincodon typus) from an aquarium collection was explored using (1)H nuclear magnetic resonance (NMR) spectroscopy and direct analysis in real time (DART) mass spectrometry (MS). Principal components analysis (PCA) of spectral data showed that individual animals could be resolved based on the metabolite composition of their serum and that two unhealthy individuals could be discriminated from the remaining healthy animals. The major difference between healthy and unhealthy individuals was the concentration of homarine, here reported for the first time in an elasmobranch, which was present at substantially lower concentrations in unhealthy whale sharks, suggesting that this metabolite may be a useful biomarker of health status in this species. The function(s) of homarine in sharks remain uncertain but it likely plays a significant role as an osmolyte. The presence of trimethylamine oxide (TMAO), another well-known protective osmolyte of elasmobranchs, at 0.1-0.3 mol L(-1) was also confirmed using both NMR and MS. Twenty-three additional potential biomarkers were identified based on significant differences in the frequency of their occurrence between samples from healthy and unhealthy animals, as detected by DART MS. Overall, NMR and MS provided complementary data that showed that metabolomics is a useful approach for biomarker prospecting in poorly studied species like elasmobranchs.
Climate change is causing shifts in animal habitats, particularly affecting the distribution of threatened marine species like whale sharks.
Projections indicate that by 2100, whale sharks could lose more than 50% of their core habitat in some areas, with significant geographic shifts that could place them in closer proximity to large ships.
The increase in whale shark interaction with shipping is expected to be dramatically higher under high emission scenarios compared to sustainable development, highlighting the urgency for better climate-threat predictions in conservation strategies for endangered marine life.
This note details the first formal report of a spinal deformation in whale sharks, Rhincodon typus. An individual whale shark with suspected kypholordoscoliosis was observed at Ewing Bank in the Gulf of Mexico during aggregation events in 2010 and 2013. Despite the significant deformity, the shark was observed feeding on fish eggs at the surface during both encounters.
Global biodiversity is under serious threat, raising doubts about current conservation governance systems and their ability to prevent species extinction.
Recent conferences, like COP15 and COP19, have brought renewed optimism for addressing these challenges, but significant barriers still hinder conservation efforts.
To tackle these issues effectively, the text emphasizes the need for alignment among legal, ecological, and sociocultural aspects of conservation, using the Rubik's cube as a metaphor to illustrate the complexity and necessity for integrated solutions.
- This study examines how managing the timing and location of tuna purse seine fishing in the western Pacific can help protect at-risk species that may get accidentally caught, known as bycatch.
- Using advanced statistical models, researchers identified "hotspot" areas where certain species, like silky sharks and whale sharks, are more frequently caught, which can guide better management practices.
- The research suggests that by shifting fishing effort away from these hotspots and enhancing communication among fishermen, there could be a balance between catching target fish and protecting vulnerable species, although more research is needed on the practicality of these strategies.
