CSPs: Spider functional traits from pitfall traps in the CSPs

Usage Rights

This data is Free within projects.

Data use is restricted to SP8

Dataset Abstract

Dataset on functional traits of epigeic spiders from the pitfall traps in the 27 CSPs. The effects of species loss on ecosystems depend on the functional characteristics of the species, i.e. the functional diversity, in a community. However, how functional diversity responds to environmental changes in natural ecosystems is only poorly understood. This particularly applies to higher trophic levels, which play a crucial role in regulating ecosystem processes and might be strongly affected by human-induced environmental changes. The dataset provides species traits that are related to resource use and which can thus be used to analyze aspects of the functional diversity of an important group of generalist predators.

Dataset Design

The list of spiders stems from the pitfall trap catches conducted from March to September 2009 (four traps per plot) in the CSPs. Body size was measured as the total length from the front of the carapace to the end of the abdomen. Up to six individuals per species were measured and mean body size (averaged across male and female data) was used as a continuous variable. Phenology was based on the main activity periods of each species over the trapping season and included as a categorical variable (early, late or whole season). Hunting type, vegetation stratum and prey range were coded as binary variables depending on whether species were web-builders or cursorial hunters, preferred forest floor habitats or higher vegetational strata, and whether they were generalists or prey specialists (e.g. many Mimetidae and Zodariidae are specialized spider and ant hunters, respectively). Data on hunting type, stratum and prey range is mostly available only on family or genus level. However, it has been shown that these traits are largely conserved within families and allow for adequate classification of species in most cases (Cardoso et al. 2011). We used data of Jocqué and Dippenaar-Schoeman (2007: Spider families of the world. Royal Museum for Central Africa, Tervuren), Cardoso et al. (2011: Global patterns of guild composition and functional diversity of spiders. PLoS ONE 6:e21710), and own observations to assign species to the respective type of hunting, preferred stratum and prey range. It is difficult to know whether species recorded with very few individuals are biologically associated to a habitat. As in many cases they only represent accidental occurrences of vagrant species, for a meaningful analysis we focused on species that were recorded with more than four individuals in the total catch. The species excluded made up on average 3.6% (±1.4 SD) of spider individuals recorded per plot and were on average smaller than the species analyzed, indicating that their functional impact is low. Species richness patterns were not affected by this procedure.

Spatial Extent

Comparative Study Plots, Gutianshan
29°08'-29°17'N
118°02'-118°11'E

Temporal Extent

Growing season 2009

Taxonomic Extent

Spiders

Freeformat files (1)

Data columns available in the raw data part of this dataset

Species
Spider species name
Data group: Spider species
Keywords: species, taxon
Values
Agelenidae_7
Atypus_1
Agelenidae_6
Castianeira_flavimaculata
Anahita_fauna
Body_length
Mean body length; Body size was measured as the total length from the front of the carapace to the end of the abdomen. Up to six individuals per species were measured and mean body size (averaged across male and female data) was used as a continuous variable
Unit: millimeter
Data group: Body length of an animal
Keywords: body length
Values
14
1.3
10.25
12
13
Stratum
Main stratum used: foliage or ground hunter
Data group: Functional spider traits
Keywords: vegetation stratum
Values
forest_floor
foliage
Hunting_type
Hunting type: cursorial hunter or web builder
Data group: Functional spider traits
Keywords: hunting type
Values
web
cursorial
Specialist
Specialized prey use (specialist) or generalist
Data group: Functional spider traits
Keywords: specialization
Values
specialist
generalist
Phenology
Main activity period (spring, fall, whole trapping season)
Data group: Functional spider traits
Keywords: phenology
Values
spring
fall
whole