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The distribution of the Africanized honey bee (AHB) in the Caribbean region is “patchy”, with some islands, such as Puerto Rico, testing positive for AHB since the mid 1990s, while other regions, including the Dominican Republic and Haiti appeared to be free of AHB. In this study we confirm, through molecular test of mitochondrial genetic material, that AHB is now present in managed colonies in the Dominican Republic. The presence of the Africanized mitotype was established using the cytochrome b/BglII assay. Results show that 39% of the colonies sampled displayed the African haplotype, and 73% apiaries had at least one Africanized colony. Six out of the eight provinces surveyed (excluding Santo Domingo and Dajabón) tested positive for the presence of AHB colonies. The results indicate that AHB is present in the Dominican Republic and that currently it may be more prevalent in the northwest region of the country. However, a more intensive survey is needed to confirm countrywide prevalence of the African genotype, and to examine the situation in neighboring Haiti.

Two forms of intraspecific nest parasitism are described for the neotropical sand waspStictia heros (Fabr.). Females behaving aggressively made aerial attacks on prey-laden females as they approached their nest for provisioning. Attacks resulted in prolonged grappling on the sand, and the relative sizes of the contestants influenced final possession of the prey. Also, the probability that returning females were attacked was directly related to the size of the prey being delivered. Females displaying marauding behavior entered the nests of other females, removed prey, and deposited it in their own nest. Females usually raided nests that were near their own nest and tended to concentrate raiding attempts on nests that previously yielded prey. We also describe the behavior associated with the delivery of hunted prey and examine possible interrelationships between wasp size, prey size and hunting trip duration.

The release of sterile males is a key component of an areawide program to eradicate the Mediterranean fruit fly, Ceratitis capitata (Wiedemann), from Guatemala and southern Mexico. The objective of our study was to assess the effects of adult diet, exposure to ginger root oil (Zingiber officinale Roscoe), and elevation on the mating competitiveness of the sterile males used in an areawide program. Sterile males were maintained on a protein-sugar (protein-fed) or a sugar-only (protein-deprived) diet and were exposed (for 4 h 1 d before testing) or not exposed to ginger root oil. In field-cage trials conducted at a high (1,500 m) and low (700 m) site, we monitored the influence of these treatments on the mating success of sterile males in competition with wild males (reared exclusively on the protein-sugar diet and without ginger root oil exposure) for wild females. Elevation and ginger root oil exposure had significant effects, with sterile males having higher mating success at the low-elevation site and ginger root oil-exposed males having greater success than ginger root oil-deprived males at both sites. Diet did not have a significant overall effect, and its influence varied with elevation (dietary protein seemed to provide an advantage at the high-elevation site but not at the low-elevation site). Possible implications of these findings for eradication programs against the Mediterranean fruit fly are discussed.