A prickly Shark, Echinorhinus cookei, filmed by an ROV in the central Pacific.
The deep-sea realm remains one of the most mysterious domains on our planet, harboring elusive and fascinating creatures that often evade our understanding. Among these intriguing creatures of the deep is Echinorhinus cookei, commonly known as the prickly shark. Belonging to the family Echinorhinidae, the prickly shark is a demersal species, meaning it resides close to the ocean floor. Unlike its close relative, the bramble shark (Echinorhinus brucus), the prickly shark boasts distinct characteristics that set it apart. For example, the prickly shark is covered in small, non-fused denticles that are stellate in shape, while the bramble shark has larger, sparse denticles that can fuse into plates with cusps. Originally described from the Hawaiian Islands, the prickly shark was once thought to have a confined distribution, with most sightings concentrated in temperate and subtropical regions of the North and South Pacific Oceans. However, recent discoveries have revealed a continuous distribution spanning from the northernmost reaches off Oregon and Japan to the southern expanses of Chile and New Zealand. These findings, including numerous records in the tropical eastern Pacific, underscore the importance of ongoing exploration and documentation efforts.
However, despite the efforts of scientists to uncover its secrets, our understanding of this species has long been hindered by limited documentation and sparse records in the wild. This scarcity of information has led to its classification as Data Deficient in the IUCN Red List, highlighting the urgent need for further research and documentation.
A recent study sheds new light on the presence of E. cookei in Panamanian waters, marking a significant addition to our knowledge of its distribution and habitat preferences. Observations were made possible through a series of submarine dives on the outer slopes of seamounts within the Cordillera de Coiba, an offshore marine protected area characterized by diverse seamounts and deep-sea trenches; equipped with advanced technology, including high-definition cameras and laser measurement tools, researchers were able to document the presence of these 12 sharks and estimate their size. The presence of aggregations, a behavior rarely observed in this species, is one that carries important implications for its conservation. “Documenting this discovery is crucial for informing future conservation and management strategies for this and other co-distributed species in the region,” the authors report. “Understanding shark aggregations, including when and how they form, is vital for species conservation as it provides insight into their behavior, distribution, and potential responses to anthropogenic threats, enabling the development of more effective management strategies to protect species.”
Location of the Cordillera de Coiba marine protected area in the exclusive economic zone (EEZ, black ... [+]
Like many marine species, prickly sharks face increasing threats from human activities, including fishing and habitat destruction. By understanding its habitat utilization and population dynamics, scientists and policymakers can develop more effective management strategies to protect this species and its ecosystem. The recent observations in the Cordillera de Coiba, the research team argues, highlights the importance of marine protected areas and the need for robust enforcement to safeguard vulnerable deep-sea habitats. “These findings underscore the urgency of further collaborative research, such as collecting long-term movement data, to uncover species interactions and behavior and lead to more successful ecosystem management and conservation efforts,” they conclude.
