Changes in spider (Araneae) assemblages in relation to succession and grazing management.

Published online
24 Dec 1992
Content type
Journal article
Journal title
Journal of Applied Ecology

Gibson, C. W. D. & Hambler, C. & Brown, V. K.

Publication language


Spiders were sampled, by suction (D-vac) and direct counts of their webs, in a controlled sheep-grazing experiment on calcareous ex-arable land and in old calcareous grassland in the UK. Results from 1985-89 are presented. Heavily grazed assemblages were dominated by a group of Linyphiidae, which were also characteristic of disturbed land. Large web-spinners were most sensitive to grazing, preferring ungrazed areas because of their dependence on rigid plant structures. DCA ordination of D-vac data suggested that only heavy grazing (in spring and autumn) produced a distinct assemblage. Three other grazed treatments produced impoverished versions of ungrazed control assemblages. The dominant successional trend was a gradual accumulation of species, especially in ungrazed controls. This process was incomplete by 1989: old grasslands contained many species, including some characteristic of calcareous grassland, which had failed to colonize the ex-arable field 7 years after abandonment. Most features of the assemblages could be explained by the effects of grazing on plant architecture, in contrast to other invertebrates studied in the same system, which were more strongly affected by plant species composition.

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