Abstract Field margins have an important ecological role in agroecosystems including hosting beneficial insect such as syrphids. However, little is known of syrphid preferences for different types field margins. Syrphids were sampled organic agroecosystem to test the hypothesis that abundance depends not only on floral resource but also margin component type, complexity, and adjacent land-use t...

Documented pollinator declines have encouraged the installation of plantings in residential, commercial and agricultural settings. Pollinator visitation among cultivars coreopsis, salvia asters was compared on 40 dates a 2-year study resulting 6,911 observations across all plant taxa with bees, butterflies syrphids well-represented. Diversity insect visitors represented differently within broad...

The Canton “El Carmen”, called the Golden Gate of Manabí, is located in coastal region Ecuador an extensive plain crossed by Suma River, foothills Western Mountain Range Andes, at altitude 236 meters above sea level.

Organic lettuce, Lactuca sativa L., producers on California's Central Coast rely on endemic syrphid flies (Diptera: Syrphidae) to suppress populations of Nasonovia ribisnigri Mosley (Homoptera: Aphididae) and other aphids affecting lettuce. Growers are using various forms of habitat manipulation to enhance biological control. We surveyed syrphids collected from organic romaine in and around the...

In surveys of apple-production areas east of the Cascade Mountains of Washington, broadleaf plantain, Plantago major Linnaeus (Plantaginaceae) was common throughout while narrowleaf plantain, P. lanceolata Linnaeus, was most common south of Orondo, Douglas County (47.7u latitude). Rosy apple aphid was the most common aphid on these two herbaceous plants; however, colonies were scarce, on only 1...

Variation in mean food availability, and in the variance around the mean, affects the growth rate during development. Previous theoretical work on the influence of environmental quality or growth rates on the phenotypic traits age and size at maturation assumed that there is no variation in growth rate or food availability within a generation. We develop a stochastic dynamic programming (SDP) m...

A model was developed to estimate the effect of predation by Episyrphus balteatus larvae on aphid populations in fields of winter wheat. Feeding rate of syrphid larvae was estimated from experiments in field cages using a Holling type-III function. During larval development, syrphids consumed a maximum of 396 aphids, which is only half the potential feeding rate reported from laboratory experim...

Variation in species' responses to abiotic phenological cues under climate change may cause changes in temporal overlap among interacting taxa, with potential demographic consequences. Here, we examine associations between the abiotic environment and plant-pollinator phenological synchrony using a long-term syrphid fly-flowering phenology dataset (1992-2011). Degree-days above freezing, precipi...