This is an 18-year study of the endangered Papilio (Pterourus) homerus, adding substantial information to our scanty knowledge of its ecology. The contraction of a once contiguous but narrow population on a single Caribbean island carries the serious threat of extinction. There are now two populations or probably metapopulations, effectively isolated from each other. The butterfly's larvae feed on Hernandia catalpaefolia and H. jamaicensis, both endemic to Jamaica, and development takes *84 days from egg to the emerged adult. Adult numbers fluctuate rapidly, with peaks in July/August each year. Egg distribution was studied at three spatial levels: the food item (leaf cluster), the patch (tree) and the habitat (each valley). Major causes of developmental mortality were Chrysonotomyia, a eulophid parasitoid of the eggs, and bacterial infection of the larvae and pupae. Critically, the mortality from this wasp was lower in undisturbed forest than in the area disturbed by agriculture, this finding having important consequences for conservation. Although there was no evidence of a decline in numbers over the last century, we believe this is an artefact due to collectors working only at the periphery of its distribution. Even assuming that its population densities have not changed, the contraction of its usable habitat implies a similar reduction in average numbers and the small populations are susceptible to disaster. The efforts of researchers, NGOs, and Government agencies have greatly increased the level of awareness, making the people in some key areas the 'protectors of the species'.

Ips calligraphus (Germar) has previously been recorded from Jamaica but this is the first record of Ips grandicollis (Eichhoff) in the island. In Jamaica, both bark beetles attack 5 species of Pinus, 4 of which had not been previously recorded. The beetles thrive mainly on freshly cut logs and weakened trees, but recently they have been rising to economic importance in plantations. Successful attack on live trees is enhanced by mass aggregation of dispersing adults during invasion. Some adults may re-emerge after a phase of oviposition and disperse to new food sources. There is degeneration of flight muscles during oviposition, and regeneration to allow for another dispersive flight. In I. calligraphus attacking Pinus caribaea there was a mean of 26.74 ± 6.86 (mean ± SE) eggs per gallery, while in I. grandicollis there was 19.29 ± 3.04. The proportion of females at emergence was 0.57 ± 0.03 and 0.05 ± 0.02 in I. calligraphus and I. grandicollis, respectively.

No abstract

No abstract

No abstract