These are what we call "cots" on the Barrow, Nore and Suir - that name does not seem to be used elsewhere? They are very like Louisiana "Bateau" in construction - very shallow, very simple. Good for slow-running rivers, moving through reeds, fishing, not for use in waves or turbulence! Materials used are usually whatever is cheap and available. Always paddled, not rowed. I saw one near Borris, Co. Carlow, with a hand-cranked "motor" made from a bicycle pedal and chain driving an outboard leg and prop - good for silent approach to fish I suppose.
These were taken in July 2004 at the bridge in Carrick-on-Suir.