The use of escape gaps set in the comers of Antillean fish traps is suggested as a management mechanism for the intensive trap fisheries of the Caribbean. Escape gaps could be rectangular or diamond-shaped. Rectangular apertures provide two dimensions (width and the diagonal) that can be adjusted to permit the escape of deep-bodied slender fishes while retaining round-bodied fishes and crustaceans. Diamond-shaped escape gaps provide height, width and, to a degree, body shape as controlling dimensions. Previous investigations have suggested that the effectiveness or fishing power oftraps might decrease when mesh size is increased. Preliminary indications from a series of tests with rectangular escape gaps are that appropriately sized escape gaps are effective in releasing undersized fish but do not significantly decrease the catchability oftarget species. Yields of deep-bodied fishes such as surgeonfish, triggerfish, hogfish, angelfish, spadefish, porgies and some of the grunts and jacks would be increased, because such fishes are invariably harvested at extremely small sizes by the hexagonal wire meshes commonly used in Caribbean trap fisheries. Morphometric information is presented for twenty-one species to estímate size at first capture with various escape gap sizes, and to calculate potential improvements in yield-per-recruit when using escape gaps. For severely depleted fisheries, the dimensions of the escape gap would need to be progressively changed as stocks of key fishery species recovered and the composition of the fish communities changed.
Escape gaps: an option for the management of Caribbean trap fisheries
Munro, J.L., Sary, Z., Gell, F.R. (2001)
p. 28-40. In: Proceedings of the 54th Annual Gulf and Caribbean Fisheries Institute.-- Providenciales Turks & Caicos Islands.November, 2001