A Shark Conservationists Toolbox: Current DNA Methods and Techniques Aiding in the Conservation of Sharks

Elasmobranchs are important members of their community. Many sharks are important apex predators that help maintain the health of their ecosystem. However, shark populations are globally declining. This is partially due to the fact that sharks are highly targeted for their fins, meat, liver oil, teeth, and skin. However, they are also killed from anthropogenic effects such as habitat destruction and pollution. Most shark species have life history characteristics that also make them more vulnerable to overfishing. Sharks are also difficult to study due to their elusive nature and identification issues. That is why molecular tools are increasingly becoming important for studying sharks. This paper discusses four different types of molecular tools: mitochondrial and nuclear DNA, environmental DNA, sequence-based, and PCR-based tools. All of these techniques are currently being used to help study and conserve sharks. These techniques can obtain important ecological information for a given species. The majority of the research has been conducted on species identification. Specifically, you can use these tools to identify a particular species of importance, or to classify the global fin trade, or even to identify species in highly processed samples. Species identification isn’t the only useful information that can be obtained however. Molecular tools can also help us better understand the species composition, stock structure, mating system, or population size of a given area. Molecular tools are still a growing area of research. In the future these techniques will continue to improve, and the information that we can learn will continue to grow. One of the biggest hurdles for this type of research is a lack of communication between geneticists and fishery managers and policy makers. Molecular tools have the potential to help with current and future policy and management. That is why it is important for anyone interested in the conservation of elasmobranchs to have a better understanding of molecular techniques

World without borders-genetic population structure of a highly migratory marine predator, the blue shark (Prionace glauca)

Highly migratory, cosmopolitan oceanic sharks often exhibit complex movement patterns influenced by ontogeny, reproduction, and feeding. These elusive species are particularly challenging to population genetic studies, as representative samples suitable for inferring genetic structure are difficult to obtain. Our study provides insights into the genetic population structure one of the most abundant and wide-ranging oceanic shark species, the blue shark Prionace glauca, by sampling the least mobile component of the populations, i.e., young-of-year and small juveniles (year; N = 348 individuals), at three reported nursery areas, namely, western Iberia, Azores, and South Africa. Samples were collected in two different time periods (2002-2008 and 2012-2015) and were screened at 12 nuclear microsatellites and at a 899-bp fragment of the mitochondrial control region. Our results show temporally stable genetic homogeneity among the three Atlantic nurseries at both nuclear and mitochondrial markers, suggesting basin-wide panmixia. In addition, comparison of mtDNA CR sequences from Atlantic and Indo-Pacific locations also indicated genetic homogeneity and unrestricted female-mediated gene flow between ocean basins. These results are discussed in light of the species\u27 life history and ecology, but suggest that blue shark populations may be connected by gene flow at the global scale. The implications of the present findings to the management of this important fisheries resource are also discussed

Highly migratory shark fisheries research by the National Shark Research Consortium (NSRC), 2002-2007

The National Shark Research Consortium (NSRC) includes the Center for Shark Research at Mote Marine Laboratory, the Pacific Shark Research Center at Moss Landing Marine Laboratories, the Shark Research Program at the Virginia Institute of Marine Science, and the Florida Program for Shark Research at the University of Florida. The consortium objectives include shark-related research in the Gulf of Mexico and along the Atlantic and Pacific coasts of the U.S., education and scientific cooperation

Population structure and connectivity of demersal sharks in isolation

Maximilian Hirschfeld studied how barriers in the ocean shape genetic and biogeographic patterns in elasmobranchs (sharks, skates and rays). A global synthesis and results from two shallow-water reef sharks revealed how physical barriers and elasmobranch biology regulate genetic connectivity in the ocean, particularly in oceanic archipelagos and Indo-Pacific coral reefs

Assessing connectivity in South Australia's Marine Parks Network

Alice Jones, Michelle Waycott, Simon Bryars, Alison Wright and Bronwyn Gillander

Shark protection plan for the Dutch Caibbean EEZ

Shark populations have steeply declined worldwide due to unsustainable overexploitation and in this the Caribbean region is no exception. Since the 1990s many initiatives have been developed to protect the most threatened species. Sharks play an important ecological role in tropical marine ecosystems and represent an important economic potential in the context of ecotourism. As the Netherlands has traditionally shown strong international leadership and commitment in biodiversity protection, a key ambition of the new Dutch Caribbean Nature Policy Plan 2013-2017, developed jointly with the Dutch Caribbean islands, is the effective implementation of shark protection