Advanced

Small-scale spatial pattern of web-building spiders (Araneae) in alfalfa: Relationship to disturbance from cutting, prey availability, and intraguild interactions

Birkhofer, Klaus LU ; Scheu, Stefan and Wise, David H. (2007) In Environmental Entomology 36(4). p.801-810
Abstract
Understanding the development of spatial patterns in generalist predators will improve our ability to incorporate them into biological control programs. We studied the small-scale spatial patterns of spider webs in alfalfa by analyzing the relationship between web locations over distances ranging from 4 to 66 cm. Using a coordinate-based spatial statistic (O-ring) and assuming a heterogeneous distribution of suitable web sites, we analyzed the impact of cutting and changes in spider abundance on web distribution. We analyzed the influence of small-scale variation in prey availability by comparing web distributions to the pattern of sticky-trap captures of Aphididae and Diptera described by a count-based spatial statistic (SADIE). Cutting... (More)
Understanding the development of spatial patterns in generalist predators will improve our ability to incorporate them into biological control programs. We studied the small-scale spatial patterns of spider webs in alfalfa by analyzing the relationship between web locations over distances ranging from 4 to 66 cm. Using a coordinate-based spatial statistic (O-ring) and assuming a heterogeneous distribution of suitable web sites, we analyzed the impact of cutting and changes in spider abundance on web distribution. We analyzed the influence of small-scale variation in prey availability by comparing web distributions to the pattern of sticky-trap captures of Aphididae and Diptera described by a count-based spatial statistic (SADIE). Cutting of alfalfa reduced the overall density of web-building spiders but had no immediate impact on the spatial distribution of their webs. Availability of aphids was highest before the alfalfa was cut and was clumped at a scale of 66 cm. Spider webs, however, were not clumped at any scale or date. In contrast, webs were regularly distributed at smaller distances (<20 cm) immediately before and after cutting. Because cursorial and web-building spiders were most active during this period, we hypothesize that the development of small-scale regularity in web locations was driven by intraguild interactions. Our results suggest that intraguild interactions contribute to the development of small-scale spatial patterns of spider webs in alfalfa. Variation in prey availability may have more of an influence on web distribution in crops with a different vegetation structure or if patterns are studied at larger spatial scales. (Less)
Please use this url to cite or link to this publication:
author
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
predator-prey association, biological control, generalist predators
in
Environmental Entomology
volume
36
issue
4
pages
801 - 810
publisher
Entomological Society of America
external identifiers
  • scopus:34548186414
ISSN
1938-2936
DOI
10.1603/0046-225X(2007)36[801:SSPOWS]2.0.CO;2
language
English
LU publication?
yes
id
2c84b97e-a5f7-479d-9054-9601946a3e8e (old id 2440514)
alternative location
http://www.scopus.com/inward/record.url?eid=2-s2.0-34548186414&partnerID=40&md5=e05e20fe19334b91fba4457fe4e1dca8
date added to LUP
2012-06-20 11:08:53
date last changed
2017-05-14 03:29:59
@article{2c84b97e-a5f7-479d-9054-9601946a3e8e,
  abstract     = {Understanding the development of spatial patterns in generalist predators will improve our ability to incorporate them into biological control programs. We studied the small-scale spatial patterns of spider webs in alfalfa by analyzing the relationship between web locations over distances ranging from 4 to 66 cm. Using a coordinate-based spatial statistic (O-ring) and assuming a heterogeneous distribution of suitable web sites, we analyzed the impact of cutting and changes in spider abundance on web distribution. We analyzed the influence of small-scale variation in prey availability by comparing web distributions to the pattern of sticky-trap captures of Aphididae and Diptera described by a count-based spatial statistic (SADIE). Cutting of alfalfa reduced the overall density of web-building spiders but had no immediate impact on the spatial distribution of their webs. Availability of aphids was highest before the alfalfa was cut and was clumped at a scale of 66 cm. Spider webs, however, were not clumped at any scale or date. In contrast, webs were regularly distributed at smaller distances (&lt;20 cm) immediately before and after cutting. Because cursorial and web-building spiders were most active during this period, we hypothesize that the development of small-scale regularity in web locations was driven by intraguild interactions. Our results suggest that intraguild interactions contribute to the development of small-scale spatial patterns of spider webs in alfalfa. Variation in prey availability may have more of an influence on web distribution in crops with a different vegetation structure or if patterns are studied at larger spatial scales.},
  author       = {Birkhofer, Klaus and Scheu, Stefan and Wise, David H.},
  issn         = {1938-2936},
  keyword      = {predator-prey association,biological control,generalist predators},
  language     = {eng},
  number       = {4},
  pages        = {801--810},
  publisher    = {Entomological Society of America},
  series       = {Environmental Entomology},
  title        = {Small-scale spatial pattern of web-building spiders (Araneae) in alfalfa: Relationship to disturbance from cutting, prey availability, and intraguild interactions},
  url          = {http://dx.doi.org/10.1603/0046-225X(2007)36[801:SSPOWS]2.0.CO;2},
  volume       = {36},
  year         = {2007},
}