Background:
White sharks are among the most widespread, charismatic, and studied predators in the ocean. However, their conservation status is concerning in many ocean sectors, most notably the Mediterranean Sea, which hosts one of the least known and most endangered populations of white sharks globally. Other lamnids in region such as shortfin mako and porbeagle shark are threatened and data-poor. Though they were historically abundant and widely distributed in the region, Mediterranean lamnids have declined to dangerously low levels of abundance in the last few decades, impacted by centuries of coastal and, more recently, industrial fishing. The IUCN lists white sharks as Critically Endangered in the region, but information about their current abundance and ecology is lacking, hindering conservation efforts.
It is now crucial to facilitate more research and exploration to advance knowledge and improve the conservation of Mediterranean white sharks and other lamnids. Specifically, we need to increase our understanding of their distribution and spatial structure. Detecting environmental DNA (eDNA) that has been shed by sharks can reveal their occurrence and movement patterns. Opportunistic sightings of elusive Mediterranean white sharks are rare, so the utility of detecting eDNA and refining the detection workflow is crucial for monitoring their population. This is why sampling in other regions of the world where white sharks reliably aggregate can offer insight into how best to refine the sampling and detection workflow. Other regions will include West Florida and Cape Cod, and can include California, South Africa, and West Australia. Furthermore, oceanographic simulations can provide novel insight into the trajectory of eDNA particles in the open ocean, helping to determine both the source and destination of eDNA shed by sharks.
Moreover, Citizen Science initiatives offer unique opportunities to raise public awareness and scale up sampling effort while reducing ship-time costs. Public scientists can take advantage of cost-efficient user-friendly sampling kits to establish a persistent monitoring program in parallel with scientific expeditions. These operations will be crucial for developing conservation and management policies to protect the last strongholds of the Mediterranean white shark and other large pelagic lamnids such as the shortfin mako and porbeagle.
Data Impact:
Virginia Tech Department of Fish and Wildlife Conservation are on a mission to monitor the world’s most charismatic top predator with next-generation technology, to fill knowledge gaps in conservation data and save white sharks from extinction in the Mediterranean Sea. With innovative methods to detect the presence of even the most sparse and elusive populations of white sharks, they aim to expand sampling efforts with scientific-led and citizen science expeditions. Our objectives are to bring eDNA sampling to dedicated sailors and scientists alike, for the purpose of testing and refining applications.
With more resources, they can upgrade kits to sample at depth, and quickly record oceanographic variables such as salinity, temperature, current etc. The scientists want to establish long-term monitoring programs by leveraging an international network of samplers. This network can be hosted on a website to facilitate access to sampling events, alert samplers to high eDNA density zones (from our models), and engage in sampling competitions. Awards and prizes can be given out to the most dedicated citizen scientists. Sampling can be facilitated with a sponsored mobile application for easy input of sampling data, access to maps of historical eDNA sampling transects and what the results were (based on laboratory processing), logging feedback and forum discussion, and more.
The team’s approach is effective and scalable for clarifying spatiotemporal patterns in white shark distribution. Therefore, the mission is to expand sampling capabilities to the entire Mediterranean Sea and to networks around the world where white shark populations exist. Doing so will significantly increase the understanding of the white shark’s biological and ecological processes; their movements and migrations, genetics, and reproductive behaviors. Contribution from scientists and citizen scientists can reveal these knowledge barriers, and effectively save white sharks and other large pelagic species from extinction in the Mediterranean and other regions of conservation concern.
How to Participate:
For more information or to participate in this project, please email our Citizen Science Manager, Haley Davis, at [email protected].
