Family Rajidae

Common names:  skates

Distribution:  Worldwide in temperate seas from shallow waters to rarely 3000 meters.  Skates are most common from subtidal to waters about 500m deep.

General description and features:  Skates are flattened with their broad pectoral fins composing a disk.  They all have long tails often with short spines or tubercles protruding along its length.  Spines are also present on their backs, the patterns of which can be used to identify some species.  These fishes might be confused with the rays (including families Dasyatidae, Urolophidae etc.) but the skates do not possess a stinger. 

Feeding:  These fishes have a mouth located on the underside of their bodies and, as might be expected, most species primarily eat prey living on or within the bottom (i.e. clams, snails, polychaetes, crabs etc.).  The teeth of some are adapted for crushing hard shelled prey.  However, the diet of some skates can be quite diverse.  Larger species have even been known to eat small macrourids and scorpaenids! 

Reproduction and life history:  Skates lay large eggs that are encased in leathery material.  Some are attached to sea pens, rocks or just cast onto the sediments.  They can take over a year to develop.  When they do the result is a miniature adult.  Skates have low fecundities (~5-20) and mature late in life.  These characteristics have made them and their cousins the sharks very vulnerable to overfishing. 

This skate (Bathyraja sp.) was filmed along a rock wall at 3100 meters in Monterey Canyon.  Anyone have any ideas on the species?