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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.

The effectiveness of formic acid and thymol in the control of the mite Varroa destructor was evaluated from June to October 2011 in an apiary of 16 Africanized honeybee colonies (the colonies did not receive chemical treatment at all) located in Atenas, Alajuela. The apiary was randomly divided in three groups (A, B and C) of 8, 5 and 3 colonies, respectively. Group A was treated with 150 g of formic acid at 65%, group B received 2 applications of 25 g thymol and colonies of group C were used as control. Varroa traps were placed on the bottom board of each colony to collect the mites. After 4 weeks, all colonies were treated with 4 strips of flumethrin to kill the remaining mites and to assess the effectiveness of the products. Furthermore, the mortality of the different stages of varroa was evaluated in capped worker brood cells checking the pupa and the bottom of the cell for mites. The effectiveness of formic acid and thymol in the control of varroa mites was 94.7% and 96.9% respectively. In colonies treated with formic acid varroa mortality occurred mainly during 72 h after application, meanwhile in the group treated with thymol the mite mortality was observed mainly one week after treatment. In addition, in the group of colonies treated with formic acid 86% of mite mortality occurred in capped brood cells, while in colonies treated with thymol and control colonies the varroa mortality in capped cells was less than 10%. In conclusion, the effectiveness of formic acid and thymol in the control of varroa mites was high, for which reason both products can be considered an alternative for the integrated management of varroa mites in Africanized honeybees colonies. [ABSTRACT FROM AUTHOR]