Aggregation and Coexistence in a Carrion Fly Community

Abstract

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Larval dispersal and predation in experimental populations of Chrysomya albiceps and Cochliomyia macellaria (Diptera: Calliphoridae)

“…We used frequency distribution to understand the association between larval predation and aggregation since aggregated distribution has been frequently employed in studies focusing on spatial patterns in the distribution of invertebrates, mainly parasites and insects (Atkinson & Shorrocks 1984, Shorrocks et al 1984, Kneidel 1985, Ives 1988, Rosewell et al 1990, Poulin 1993, Sréter et al 1994, Umoru 1994.…”

Are natural microcosms useful model systems for ecology?

“…A third group of models [30,31] have shown that species co-existence at the metacommunity level can be facilitated not only by local effects, such as resource heterogeneity, but also by larger scale effects, such as patterns of spatial aggregation. As aggregation of the superior competitor increases, it occupies fewer patches, creating a probabilistic refuge for inferior competitors.…”

“…As aggregation of the superior competitor increases, it occupies fewer patches, creating a probabilistic refuge for inferior competitors. Some of the best evidence for the aggregation hypothesis has come recently from natural microcosms, specifically insect larvae in fungal sporocarps [32,33], carrion [31] and fallen fruit [30,34].…”

High host densities dilute sea lice Lepeophtheirus salmonis loads on individual Atlantic salmon, but do not reduce lice infection success

“…However, empirical studies in terrestrial systems (Morand & Guégan 2000, Šimková et al 2002 have indicated a positive correlation between prevalence and mean number of parasites per host, hence prevalence would be higher at low host densities for mobile parasites. Degree of aggregation refers to the parasite distribution among individuals within a group of hosts (Ives 1991) and is positively correlated with prevalence (Stanko et al 2006). Together, previous evidence from other systems suggests that host density will influence most infection parameters in the salmon−sea lice, host−parasite system.…”