Hidden Nursery: Lanternsharks Surprise Scientists

Deep-sea monitoring programs between 2023 and 2025 in the Adriatic Sea, off the coast of Albania, have uncovered a significant population of velvet belly lanternsharks (Etmopterus spinax). These sharks, once considered scarce visitors, were found in substantial numbers between 1,476 and 2,133 feet.

The consistent presence of neonates, juveniles, and gravid females indicates that sections of the Adriatic continental slope are functioning as crucial nursery grounds for this species. This discovery challenges previous assumptions about the sharks' rarity in the region.

A key finding emphasizes the impact of fishing methods. Sharks caught in bottom trawls exhibited 100 percent mortality, while those caught on longlines sometimes survived. This disparity underscores the importance of fishing techniques in deep-sea ecosystems, where recovery is slow.

Furthermore, DNA analysis revealed moderate genetic diversity, with six new haplotypes identified. This suggests the Adriatic population, while partially isolated, is shaped by both movement and restriction, indicating a unique regional genetic profile.

The findings suggest that deep-sea fisheries are operating in poorly understood environments. There's a critical need to map these ecosystems and understand their biological intricacies before industrial extraction potentially disrupts delicate balances and leads to irreversible declines.