In situ observations of deep-living skates in the eastern North Pacific

• Published in: Deep-sea research. Part I, Oceanographic research papers Oceanographic research papers, 2019-10, Vol.152, p.103104, Article 103104
• Main Authors: Kuhnz, L.A., Bizzarro, J.J., Ebert, D.A.
• Format: Article
• Language: English
• Subjects: Deep-sea; Habitat associations; In situ; Multi-access identification key; Oxygen-minimum zone; Skates; Spatial distribution; Video survey
• ISSN: 0967-0637; 1879-0119
• DOI: 10.1016/j.dsr.2019.103104

We report on 18 years of in situ observations of seven skate species (2192 individual observations) in the eastern North Pacific (Vancouver Island, Canada to the Gulf of California, Mexico) between 200 and 3322 m depth. Biological (species, sex, maturity, behavior) and abiotic (geographic location, depth, habitat type, temperature, oxygen) data were evaluated for each species. This study extends the depth and geographic ranges of Bathyraja microtrachys and B. trachura. Additional species studied include Amblyraja hyperborea, B. abyssicola, B. kincaidii, B. spinosissima, and Beringraja rhina. Bathyraja trachura was shown to be uniquely tolerant of low oxygen environments and B. spinosissima is distinctive in that it was most frequently found actively swimming over lava fields. Our video recording of a potentially undescribed species at 3321 m represents the deepest reported in situ visual observation of a skate to date. •This is the first large-scale, long-term, in situ assessment of skates in deepwater (200–3322 m).•In situ observations provide enhanced spatial and behavioral data on deep-living skates.•Video observations provide baseline information for assessing change in distributions.•Expansion of known depth and geographic ranges for two species.•Bathyraja trachura appears to be uniquely tolerant of low-oxygen environments.