Lower infestation on control plants was correlated with higher total bird abundance, but not with predator abundance or vegetation complexity. Although migrant predators overall did not respond to vegetation complexity variables, the 3 primary species increased with proximity to noncoffee habitat patches. Average relative bird abundance and diversity and relative resident predator abundance increased with greater shade-tree cover. We identified 17 potential predator species (73% were wintering Neotropical migrants), and 3 primary species composed 67% of migrant detections.
Coffee plants excluded from foraging birds had significantly higher borer infestation, more borer broods, and greater berry damage than control plants. We conducted a bird-exclosure experiment on coffee farms in the Blue Mountains, Jamaica, to measure avian pest control of berry borers, identify potential predator species, associate predator abundance and borer reductions with vegetation complexity, and quantify resulting increases in coffee yield. Researchers have demonstrated that birds reduce insect abundance on coffee farms but have not documented avian control of the berry borer or quantified avian benefits to crop yield or farm income. The coffee berry borer (Hypothenemus hampei) is the world's primary coffee pest. invicta may promote aphid populations early in the growing season, it is an important predator of bollworm and beet armyworm eggs later in the season.Ĭoffee farms can support significant biodiversity, yet intensification of farming practices is degrading agricultural habitats and compromising ecosystem services such as biological pest control. Overall, the results of this study show that although S. invicta and native ants in beat bucket samples do not closely reflect the frequency with which these predators prey on noctuid eggs. These observations suggested that the relative frequencies of minute pirate bug, cotton fleahopper, S. invicta seven of eight predators sampled were similarly represented in beat bucket samples and nocturnal observations of beet armyworm egg mass predation, whereas minute pirate bug occurred at a higher frequency in beat bucket samples relative to nocturnal observations. invicta and native ants lower in beat bucket samples compared with their relative frequencies in nocturnal observations of predation upon beet armyworm egg masses. invicta, the relative frequencies of minute pirate bug and cotton fleahopper were higher, and of S. Predation of sentinel bollworm eggs and beet armyworm egg masses was approximately 1.5 and 4.1 times greater, respectively, in the presence of S. (52%), spiders (13%), and minute pirate bug (Orius sp.) (13%) where S.
invicta was present, and by the mite Abrolophus sp. invicta (68%) and cotton fleahopper, Pseudatomoscelis seriatus (Reuter) (21%), where S. Most predation of beet armyworm egg masses, measured via direct nocturnal observations, was due to S. invicta versus in its absence, although aphid populations did not reach economic levels. In central Texas, cotton aphid populations were approximately 5.5 times greater and predation of sentinel bollworm eggs 2 times greater in the presence of S. The effects of the red imported fire ant, Solenopsis invicta Buren (Hymenoptera: Formicidae), on cotton aphid, Aphis gossypii Glover, populations and its predation of bollworm, Helicoverpa zea (Boddie), and beet armyworm, Spodoptera exigua (Hübner), (both Lepidoptera: Noctuidae) eggs were evaluated in cotton under field conditions during 20 in central and northern Texas. Overall, the results suggested that boll weevil eradication with malathion ULV negatively impacts red imported fire ant abundance and foraging and predatory activities in cotton fields. Also in the field, beet armyworm (Spodoptera exigua) egg predation rates were lower in malathion ULV treated plots relative to untreated plots. In the field, fire ant densities on cotton plants treated with malathion ULV were lower for up to 3 weeks after treatment compared to untreated cotton plants.
Malathion ULV was acutely toxic to fire ant under laboratory conditions, and had a strong repellent effect, so reducing foraging activity, in the greenhouse. Malathion ULV had strong, negative impacts upon fire ant survivorship, foraging, and predation in cotton fields. This study examined how malathion ULV, as applied for boll weevil (Anthonomus grandis grandis) eradication in the southern USA, may impact red imported fire ant survivorship, foraging activity, and predation of lepidopteran pests. Red imported fire ant, Solenopsis invicta (Buren), is a major pest in the southern USA, though recent studies suggest it may act also as a natural enemy.
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