Francesco Ferretti ^1* Brendan Shea ¹ Chiara Gambardella ^2,3 Jeremy Jenrette ¹ Stefano Moro ³ Khaled Echwikhi ⁴ Robert J. Schallert ^5,6 Austin Gallagher ⁷ Barbara A. Block ⁸ Taylor Chapple ⁹

• ¹ Department of Fish and Wildlife Conservation, College of Natural Resources and Environment, Virginia Tech, Blacksburg, Virginia, United States
• ² Marche Polytechnic University, Ancona, Marche, Italy
• ³ Anton Dohrn Zoological Station Naples, Naples, Campania, Italy
• ⁴ Gabes University, Gabès, Gabes, Tunisia
• ⁵ Stanford University, Stanford, California, United States
• ⁶ Independent researcher, Washington, DC, United States
• ⁷ Beneath the Waves, Inc., Herndon, Virginia, United States
• ⁸ Hopkins Marine Station, School of Humanities and Sciences, Stanford University, Pacific Grove, California, United States
• ⁹ Coastal Oregon Marine Experiment Station, College of Agricultural Sciences, Oregon State University, Newport, Oregon, United States

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 globally.Though they were historically abundant and widely distributed in the region, Mediterranean white sharks have declined to dangerously low abundance levels, impacted by centuries of coastal and, more recently, industrial fishing. The IUCN lists this species as Critically Endangered in the region, but information about its current abundance and ecology is scarce, hindering effective management and conservation. Here, we describe our initial effort to find and track the remaining Mediterranean white sharks and report what we have learned from these activities. In 2021-2023, we conducted three pilot expeditions in the Sicilian Channel, covering four major sites, collecting 159 eDNA samples, and conducting 359 hrs of pelagic mid-water baited video surveys, 43 hours of deep-water benthic baited video surveys, and 111 hrs of fishing. Baited video surveys detected 42 species of bony fishes, elasmobranchs, marine mammals, and turtles. We detected white sharks at four sites from eDNA samples. Though we did not observe white sharks directly, these activities supported the identification of one of the last strongholds of this population in the region and started a multi-institutional white shark conservation program in the Mediterranean Sea, aiming to track the last white sharks in the region, estimate their abundance and extinction risk, characterize the species' ecology and inform management and conservation.