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Summary. Two common components, identified as
(E)-11-hexadecenal (E11-16:Ald) and (E,E)-10,12-hexadecadienal
(E10E12-16:Ald), were found in the extract of virgin females of two sympatric pyralid moths, Terastia subjectalis
Lederer, and Agathodes ostentalis (Geyer). The amount of E11-16:Ald and E10E12-16:Ald was 0.12 and 2.8 ng/female
for T. subjectalis and 2.0 and 1.8 ng/female for A. ostentalis,
respectively. Hexadecanal (16:Ald) was also found at
0.7 ng/female in the extract of A. ostentalis, but EAG activity was unclear. In the field, T. subjectalis and
A. ostentalis
males were captured with species specific blends in the proportions
of 5:95 and 50:50 blends. Blends attractive to one
species did not attract the opposite one. Rubber septa loaded
with 1 mg each of 5:95 and 50:50 blends of E11-16:Ald and
E10E12-16:Ald were as attractive as two virgin females of
T. subjectalis and
A. ostentalis
, respectively. This demonstrated
that different ratios of shared pheromone components could
provide species specific cues for critical mate location in the
two sympatric pyralid moths. It is suggested that directional
selection probably occurs in the pheromone blends in opposite
directions in both species. 相似文献
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JOANNA GRAND‡ JOHN BUONACCORSI† SAMUEL A. CUSHMAN CURTICE R. GRIFFIN MAILE C. NEEL 《Conservation biology》2004,18(4):1063-1077
Abstract: In the northeastern United States, pitch pine ( Pinus rigida Mill.)–scrub oak ( Quercus ilicifolia Wang.) communities are increasingly threatened by development and fire suppression, and prioritization of these habitats for conservation is of critical importance. As a basis for local conservation planning in a pitch pine–scrub oak community in southeastern Massachusetts, we developed logistic-regression models based on multiscale landscape and patch variables to predict hotspots of rare and declining bird and moth species. We compared predicted moth distributions with observed species-occurrence records to validate the models. We then quantified the amount of overlap between hotspots to assess the utility of rare birds and moths as indicator taxa. Species representation in hotspots and the current level of hotspot protection were also assessed. Predictive models included variables at all measured scales and resulted in average correct classification rates (optimal cut point) of 85.6% and 89.2% for bird and moth models, respectively. The majority of moth occurrence records were within 100 m of predicted habitat. Only 13% of all bird hotspots and 10% of all moth hotspots overlapped, and only a few small patches in and around Myles Standish State Forest were predicted to be hotspots for both taxa. There was no correlation between the bird and moth species-richness maps across all levels of richness ( r =−0.03, p = 0.62). Species representation in hotspots was high, but most hotspots had limited or no protection. Given the lack of correspondence between bird and moth hotspots, our results suggest that use of species-richness indicators for conservation planning may be ineffective at local scales. Based on these results, we suggest that local-level conservation planning in pitch pine–scrub oak communities be based on multitaxa, multiscale approaches. 相似文献
3.
Small mammals are important predators of gypsy moths (Lymantria dispar L.), which are major defoliators of deciduous forests in the northeastern United States. Abundance and habitat relationships
of small mammals were studied during summers 1984 and 1985 on forested sites at Moshannon and Rothrock state forests in two
physiographic regions of Pennsylvania (Allegheny High Plateaus Province and Valley and Ridge Province, respectively) that
varied in potential susceptibility to defoliation. The white-footed mouse (Peromyscus leucopus), which is a major vertebrate predator of gypsy moths, was the most common small mammal on all sites. Of the four common
species, northern short-tailed shrews (Blarina brevicauda), southern red-backed voles (Clethrionomys gapperi), and white-footed mice were more abundant at Moshannon compared to Rothrock State Forest, but masked shrews (Sorex cinereus) were more abundant at Rothrock. Elevation was a major factor affecting abundance and distribution of small mammals. Because
of the greater abundance of small mammals and more suitable physiographic features at Moshannon compared to Rothrock State
Forest, small mammals may be more effective as predators on gypsy moths in the Allegheny High Plateaus than the Valley and
Ridge Province of Pennsylvania. 相似文献
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