Habitat
Deep oceanic waters by day (300–500 m), shallower at night.
All species
Bigeye Thresher Shark
Alopias superciliosus
Not aggressive
Identified by enormous upward-facing eyes and a tail nearly as long as the body.
Maximum size
3.4–4.9 m
Aggressiveness
Not aggressive
Ecology
Performs strong daily vertical migrations. Found in the deeper Atlantic-Mediterranean exchange waters off Gibraltar.
Feeding
Stuns schooling fish and squid with whip-like strikes of the elongated upper tail lobe.
Behaviour
Usually solitary; rarely encountered by recreational divers due to depth.
Safety notes
No recorded attacks on humans. Treat with respect — the tail strike can injure.
Conservation status
IUCN: Vulnerable.
Sources & Citations
Data compiled from peer-reviewed and authoritative open sources. Last reviewed 2026.
- IUCN Red List of Threatened Species
Conservation status for each species.
- The Shark Trust — Species Database
Biology, ecology and identification.
- FishBase
Maximum sizes, distribution and life-history data.
- Florida Museum — International Shark Attack File
Documented species behaviour around humans.
- Nature Gibraltar / Gibraltar Ornithological & Natural History Society
Local marine fauna records around the Strait.