Kingdom: Animalia

Class: Chondrichthyes

Order: Rajiformes

Family: Rajidae

Genus: Dipturus

Species: D. batis

Physical Description

The Common Skate has a long and pointed snout giving the disc a broadly rhombic shape with the front margins distinctly concave. The dorsal surface of the disc is olive-grey or brown with a variable pattern of light spots and dusky blotches. In sub-adults there is often a marking on each pectoral fin resembling an eye spot. The ventral surface of the disc is black in juveniles and fades to grey as the animal matures. The mucus pores on both sides of the disc are marked with black spots and short streaks which are particularly numerous on the lower surface. Juveniles are smooth on both surfaces of the disc but often have large orbital thorns. Adults are partly prickly on both the upper and lower surfaces but have no thorns on the disc. There are two rows of 12-18 thorns along the tail (measured from the cloaca) and normally one or two thorns between the dorsal fins. Often there are thorns along the lower edges of the tail, particularly so in females. They are the largest skate found in European waters with females reaching a maximum total length of 285cm. They have between 40 and 56 rows of teeth and may live for 50-100 years

Biology and Behavior

The Common Skate has been recorded as feeding on several species of skate, gurnards, flatfishes, pilchards, Lobsters, crabs and cephalopods. It hunts actively, enveloping prey before consuming it. Mid-water species are captured by the skate propelling itself rapidly upward, enveloping and gripping the fish before returning to the seabed to consume it. The Common Skate takes around 11 years to reach sexual maturity at a length of around 150cm for males and 180cm for females. Females only breed once every year, mating in spring and laying up to 40 eggcases during summer which are deposited in sandy or muddy flats. These eggcases are large, measuring up to 25cm long (excluding the horns) and 15cm wide and are covered with close-felted fibres. They have been reported as being loose on the seabed and occasionally secured between rocks. The embryos take between 2–5 months to develop depending on temperature and the juveniles are born measuring 21-22cm long

Habitat and Distribution

Like most skates and rays, the Common Skate is a bottom dwelling species that is found from coastal waters to a depth of approximately 600m (1,970ft), although it is most commonly found around 200m (670ft). Unlike most other skate, it is active both day and night. Also it is quite common to find them moving about in small same sex/age groups. Populations of D. batis are found off the coasts of Isles of Scilly, western British Channel, west and north Ireland, west Scotland and Orkney. Wider distribution includes Atlantic coasts from Madeira and northern Morocco northward to Iceland including the North Sea. Also found in western parts of the Baltic and the western and northern Mediterranean although here it is very rare.

Reference:

http://www.arkive.org/flapper-skate/dipturus-batis/

http://www.snh.gov.uk/docs/A1209891.pdf

https://www.sharktrust.org/shared/downloads/factsheets/common_skate_st_factsheet.pdf

http://www.uk-fish.info/pages/commonskate.html