scubaseason

Common Thresher Shark

Alopias vulpinus

Sighting evidence at Aljezur Seamount, Algarve

Thresher sharks use their elongated upper tail lobe to stun schooling fish and are occasionally observed circling the seamount during summer when mackerel and sardine schools are at peak abundance. They are a IUCN Vulnerable species making their Algarve presence a significant conservation signal for the health of this little-visited offshore site. Encounters are typically brief — a single pass at depth — but unforgettable.

Evidence at this site

No confirmed records on file at this site

Common Thresher Shark is listed as a curated species here based on historical reports.

How is this calculated?

Sighting evidence is compiled from iNaturalist observation records within a set proximity radius, filtered for quality-grade observations. “Last confirmed” is the date of the most recent research-grade record. Record count covers a rolling 24-month window. Confidence reflects record count, recency, and consistency of seasonal signal.