Eye on Nature: Your notes and queries for Ethna Viney

Triggerfish, rooks and jackdaws

Spiny fins: the triggerfish that Meic Haines found on the Gowe Peninsula, in Wales

While walking with friends on a very windswept strand on the northwestern tip of the Gower Peninsula, in Wales, we discovered the quite large dead fish in my photograph. Have you any idea what it is?

Meic Haines
Swansea, Wales

It is a grey triggerfish, Balistes capriscus. Its usual length is about 40cm, but it can grow bigger. The triggerfish gets its name from its spiny dorsal fins: it can raise and lock its first, very strong fin, to use as a weapon, or to wedge itself in a crevice as a defence; it then releases it using a trigger in the second dorsal fin. Triggerfish feed on molluscs; they have come from farther south in the Atlantic and are at their northern limit in these islands. Evidence of breeding has yet to be found.

One of my treasured memories is of crows busily building their nests, and their caws as they worked; then the varied pitches of the caw during their busy time later, when they fed their young. In autumn and winter the voice changes again. I then lived in Co Mayo, where we called them crows, but here in Co Kildare they are called rooks. What is their correct name?

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Shirley Gibson
Celbridge, Co Kildare

Rook is the proper name, or jackdaw for the smaller black bird. Crow is the family name. Rooks, jackdaws, grey crows (also called hooded crows), magpies and jays are all members of the crow family.

Rooks are starting to get busy and are displaying at the rookery by bowing and fanning out their tails. Even when they come down to eat the remains of breakfast, they lose no opportunity to impress the females.

Albert Nolan
Newport, Co Tipperary

Ethna Viney welcomes observations and photographs at Thallabawn, Louisburgh, Co Mayo, or by email at viney@anu.ie. Please include a postal address