Thornback Ray

Photo: Octávio Mateus · CC BY-NC

Thornback rays rest on the sandy patches between the limestone formations, partially burying themselves in the sediment during the day and emerging at dusk to hunt crustaceans and small fish across the sandy corridors. They are a near-threatened species in European waters where bycatch pressure is high, making the Algarve's rocky coast — where trawling is impossible — a refuge population of conservation significance. Females deposit characteristic mermaid's purse egg cases that are frequently found wedged in rock crevices.