TY - JOUR

T1 - The importance of canopy complexity in shaping seasonal spider and beetle assemblages in saltmarsh habitats

AU - Ford, Hilary

AU - Evans, Ben

AU - van Klink, Roel

AU - Skov, Martin

AU - Garbutt, Angus

PY - 2017/4/1

Y1 - 2017/4/1

N2 - 1. Habitat structure, including vegetation structural complexity, largelydetermines invertebrate assemblages in semi-natural grasslands. The importance ofstructural complexity to the saltmarsh invertebrate community, where the interplaybetween vegetation characteristics and tidal inundation is key, is less well known.2. It was hypothesised that canopy complexity would be a more important predictor ofspider and beetle assemblages than simple vegetation attributes (e.g. height, communitytype) and environmental variables (e.g. elevation) alone, measured in two saltmarshregions, south-east (Essex) and north-west (Morecambe Bay) U.K. Canopy complexity(number of non-vegetated ‘gaps’ in canopy≥1mm wide) was assessed using side-onphotography. Over 1500 spiders and beetles were sampled via suction sampling, winterand summer combined.3. In summer, saltmarshes with abundant spider and beetle populations were characterisedby high scores for canopy complexity often associated with tussocky grassor shrub cover. Simple vegetation attributes (plant cover, height) accounted for 26% ofvariation in spider abundance and 14% in spider diversity, rising to 46% and 41%, respectively,with the addition of canopy complexity score. Overwintering spider assemblageswere associated with elevation and vegetation biomass. Summer beetle abundance, inparticular the predatory and zoophagous group, and diversity were best explained byelevation and plant species richness.4. Summer canopy complexity was identified as a positive habitat feature for saltmarshspider communities (ground-running hunters and sheet weavers) with significant ‘addedvalue’ over more commonly measured attributes of vegetation structure.

AB - 1. Habitat structure, including vegetation structural complexity, largelydetermines invertebrate assemblages in semi-natural grasslands. The importance ofstructural complexity to the saltmarsh invertebrate community, where the interplaybetween vegetation characteristics and tidal inundation is key, is less well known.2. It was hypothesised that canopy complexity would be a more important predictor ofspider and beetle assemblages than simple vegetation attributes (e.g. height, communitytype) and environmental variables (e.g. elevation) alone, measured in two saltmarshregions, south-east (Essex) and north-west (Morecambe Bay) U.K. Canopy complexity(number of non-vegetated ‘gaps’ in canopy≥1mm wide) was assessed using side-onphotography. Over 1500 spiders and beetles were sampled via suction sampling, winterand summer combined.3. In summer, saltmarshes with abundant spider and beetle populations were characterisedby high scores for canopy complexity often associated with tussocky grassor shrub cover. Simple vegetation attributes (plant cover, height) accounted for 26% ofvariation in spider abundance and 14% in spider diversity, rising to 46% and 41%, respectively,with the addition of canopy complexity score. Overwintering spider assemblageswere associated with elevation and vegetation biomass. Summer beetle abundance, inparticular the predatory and zoophagous group, and diversity were best explained byelevation and plant species richness.4. Summer canopy complexity was identified as a positive habitat feature for saltmarshspider communities (ground-running hunters and sheet weavers) with significant ‘addedvalue’ over more commonly measured attributes of vegetation structure.

U2 - 10.1111/een.12373

DO - 10.1111/een.12373

M3 - Article

VL - 42

SP - 145

EP - 155

JO - Ecological Entomology

JF - Ecological Entomology

SN - 0307-6946

IS - 2

ER -