Dynamics of spider colonization of apple orchards from adjacent deciduous forest

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Abstract

The colonization of foliage-dwelling spiders into insecticide-free “micro” apple orchards at two distances (10 and 50 m) from an adjacent source habitat of deciduous forest was quantified in southern Québec, Canada. Both colonization rate and composition of colonizing spider assemblages were affected by distance at this small spatial scale: the samples from the micro-orchards 10 m from the forest were intermediate in composition between the assemblages in the deciduous forest and those in the micro-orchards 50 m from the forest. Spider species found in micro-orchards were the same as those documented from collections from older, insecticide-free orchards although species evenness was higher in the older orchards indicating that species composition shifts over time within the habitat. Maintaining deciduous forest near to orchards will provide a source of annual colonists for spider populations within the orchard.

Introduction

Foliage-dwelling spiders are abundant and species-rich in perennial crops such as apple orchards (Dondale et al., 1979, Samu et al., 1997) and are among the first natural enemies to colonize newly planted fruit trees (Whalon and Croft, 1986, Gut et al., 1988, Rathman and Brunner, 1988). However, the role of neighbouring spider communities as sources for crop communities is unclear. For example, some studies have found that arable crops and their adjacent habitats have dissimilar spider fauna (Bishop and Riechert, 1990, Samu et al., 1997, Samu and Szinetár, 2002) indicating that long-distance dispersal is the main source of colonists (Bishop and Riechert, 1990). Schmidt and Tscharntke (2005) suggest, however, that adjacent fields are sources of colonists to crops, but that agrobionts more readily colonize the crops than other species, leading to a dissimilarity in assemblage composition. In orchards, the relative abundance of foliage-dwelling spiders decreases from the edge of the orchard to the center (Bogya et al., 2000, Miliczky and Horton, 2005), which correlates with increased distance from adjacent habitat (Miliczky and Horton, 2005). Surveys in several apple orchard agroecosystems (Sackett et al., 2008) show that orchards and immediately adjacent forests harbour similar spider assemblages, implying they act as source patches on a local scale.

In this study the colonization by foliage-dwelling spiders of apple orchards in southern Québec, Canada, was investigated. This entails the initial arrival and establishment of spiders onto orchard trees (“colonization”) rather than the more complex process of community assembly, which is a result not only of initial colonization but also of biotic interactions and environmental factors over time. The first objective was to determine if spiders colonize orchards from adjacent deciduous forest, and if the species composition of the colonists changes over small distances (10–50 m) from the source populations. Second, the phenology, abundance, and species turnover of spiders colonizing newly established orchards was quantified: understanding these phenological patterns is relevant to the timing of other pest management techniques. Third, the spider species that colonized newly planted orchards were compared to species in long-established orchards to understand the relative contribution of colonization to the long-term composition of spider assemblages in apple orchards.

Section snippets

Methods

Spider colonization was measured in 12 small “micro-orchards”, each consisting of ten 3-year-old apple trees (1.75–2 m in height). The trees in a micro-orchard were planted within a 1.2 m × 0.5 m plot. Orchard trees are normally planted further apart, but this close planting allowed the foliage of the trees to form a block of foliage approximating what is found for individual trees in an older, established orchard. The trees included 10 cultivars of apple, and each micro-orchard was planted with a

Results

In total, 3511 spiders, from 11 families and 45 species, were collected in 2006: 981 spiders from the forest samples, 1339 from the micro-orchards 10 m from the forest, 1122 from the micro-orchards 50 m from the forest, and 69 from the field. Ninety-one percent of the spiders were immature, and 3125 individuals (89% of the total) were identified to the level of species (63%) or to a genus (26%) where only one species within the genus was commonly collected in the area (Dondale et al., 1979,

Discussion

There was a gradient of increasing similarity of the micro-orchard spider assemblages to those in the forest as the distance from the forest decreased (Fig. 1). Despite the similarity, the gradual change in species assemblages in micro-orchards with distance from the forest, and the significant differences in composition between them, suggest that the dispersal dynamics of foliage-dwelling spiders change at a relatively small spatial scale. Of the 10 most common spider species sampled in the

Acknowledgements

We thank the staff at the Agriculture and Agri-Food Canada experimental farm in Frelighsburg for their valuable advice and assistance with the growing of the apples, and Elisabeth Marks, Greg Crutsinger, and Nathan Sanders for feedback on the manuscript. This work was supported by a matching fund between Agriculture and Agri-Food Canada and the Federation of Québec apple growers; the Department of Natural Resource Sciences (McGill University); the National Science and Engineering Council of

References (23)

  • C.D. Dondale et al.

    The Orb-weaving Spiders of Canada and Alaska (Araneae: Uloboridae, Tetragnathidae, Araneidae, Theridiosomatidae)

    (2003)
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