Karl A. Aiken

Reproduction, diet and population structure of the mountain mullet, Agonostomus monticola, in Jamaica, West Indies

Reproduction, feeding and population structure were investigated in the mountain mullet, Agonostomus monticola, in eastern Jamaica between 1982 and 1986. Female fishes just outnumbered males 1.2 : 1. Minimum size at maturity for females was 123 mm fork length (FL) and 96 mm FL for males. Mean size at maturity for females was 165.8 mm FL (S.D.=1.61) and for males was 148.4 mm FL (S.D.=2.97). Fecundity was 340 000 eggs for a 25 g ovary. Fecundity (F) was related to size by the equation F=153.8 FL1.36. Mean lengths of males and females captured by all methods were 129.4 mm (S.D.=5.56) and 160.4 mm FL (S.D.=0.70), respectively. A. monticola was found to be chiefly an insectivorous feeder. The major food items found in stomach contents in ranked sequence were insects, freshwater prawns, plant detritus and algae.

The queen conch fishery on Pedro Bank, Jamaica : discovery, development, management

The history, methods, problems and regulation of fishing of the last remaining large queen conch resource in the world, located on a Jamaican fishing bank, are examined. The fishery activities for the queen conch, Strombus gigas Linnaeus are briefly described with the main activities in the industrial sector which produce the bulk of the harvest, which is exported. There are a few large producers harvesting the single major fishing ground of Pedro Bank, southwest of Kingston. These fishers harvested at least 1500 t annually between 1992 and 1998. Management is by licensing, individual quotas and a close season from July to October. Regulations related to CITES are thought to greatly assist in making licensed harvesters provide catch data to the Fisheries Division. The industrial operators have provided funding to undertake stock assessment studies in 1994 and again in 1997. We highlight the focus on management on a participatory consensual approach with meetings with all players in the industry. The conch fishery is thought to be one of the few areas of the Jamaica fishery where there is close and successful collaboration between fishers and the Fisheries Division. It provides an example of how rapid, precautionary, participatory action can provide an adequate basis for management until more definitive scientific information becomes available. The status of the conch fishery is thought to be sustainable at present, once reductions are made to the annual quota.

The Establishment of the North American Bullfrog, Rana catesbeiana (Amphibia, Anura, Ranidae) in Jamaica

The presence of the newly introduced Rana catesbiana in Jamaica is recorded for the first time. Its feeding habits are comparable to those of R. catesbeiana in North America. The bullfrogs were found to be inhabiting a large area of swamp and to have begun to colonize a similar neighboring area. No topographical or environmental features which could limit these animals are apparent and it is predicted that their spread will become islandwide. Most of the land below the 100ft contour is around sea level and can be classified as herbaceous swamp (Asprey and Robbins, 1953) with a network of rivers meandering through it. The purpose of the introduction was to populate the area with a commercially valuable animal. In 1969 reports of isolated sightings and bellowing of the frogs during and after heavy rains in May made it evident that they had established themselves. Subsequent reports indicated that fishermen were catching some of the frogs in their traps and were showing concern that the frogs were destroying the shrimp upon which their livelihood depended. Concern over the matter prompted this study, the purpose of which was to determine: a) The feeding habits of the frog in its new environment. b) The extent to which the animals have spread.