Title

Diel Vertical Migration of Loosejaw Dragonfishes (Teleostei: Stomiidae: Malacosteinae) in the Atlantic Ocean

Event Name/Location

EOS Trans. AGU Ocean Sciences Meeting, Honolulu, Hawaii, February 20-24, 2006

Document Type

Poster

Publication Date

2-2006

Abstract

The diel vertical migration (DVM) of three genera of the stomiid subfamily Malacosteinae (Photostomias, Aristostomias, and Malacosteus) were analyzed from capture records of nearly 300 specimens in the Atlantic Ocean. To account for broad temporal and geographic scales encountered in this study, local time of capture was transformed to a corrected time representing position in a solar day. Species of Photostomias and Aristostomias undertake asynchronous DVMs characterized by a residence in the mesopelagic zone during the day and separate migrating and non-migrating subpopulations at night. In species ofPhotostomias, the nighttime epipelagic (<250 >m) population was smaller than the nighttime mesopelagic (>600 m) population and the daytime mesopelagic population was stratified by size across the 800-m bathycline. In species of Aristostomias, few specimens were caught in the mesopelagic zone during the day and only small specimens were captured in the mesopelagic zone at night, indicating that sampling depth was not adequate to capture the bulk of the mesopelagic daytime population and the entire size range of the non-migrating nighttime subpopulation. Species of Photostomias and Aristostomias migrated at approximately 90--82 m· h -1 and 194--223 m· h -1, respectively, corresponding to the migration rates of known prey for these taxa. In contrast, species of Malacosteus were distributed below 600 m, did not regularly migrate to the epipelagic zone, and were stratified across the 700-m bathycline. From these data, relationships between DVM patterns, morphology, and foraging ecology are inferred.

Comments

Eos Trans. AGU, 87(36), Ocean Sci. Meet. Suppl.

Additional Comments

Identifier OS46O-02.