Arthropod Assemblages in a Montane Wetland Complex: Influences of Adjoining Lotic and Lentic Habitat and Temporal Variability

Abstract

Our objective was to gain an understanding of the influences of habitat context and seasonal and interannual factors on arthropod assemblage structure in a wetland environment. We hypothesized that river and pond riparian habitats in the wetland would have greater diversity and abundance than core wetland habitat, and that these differences would be driven by aquatic subsidy via emerging aquatic insects. We also hypothesized that diversity and abundance of terrestrial fauna would decline through the dry summer. We sampled the study wetland, in Yosemite National Park, California, USA, through the growing seasons of 2013 and 2014; a large wildfire (> 100,000 ha) burned the entire study site during late summer of 2013. Assemblage structure was strongly influenced by habitat context, season, and year. Diversity and abundance were high at the river riparian sites, but these results were driven by a diverse and abundant terrestrial fauna, rather than by large numbers of emerging aquatic insects. Faunal assemblages became increasingly depauperate through the summer, likely due to drying of wetland habitat in this hot Mediterranean-type climate. Fire probably had a strong influence on faunal assemblages and vegetation structure, but we cannot rule out interannual variability independent of the fire.

River food chains lead to riparian bats and birds in two mid‐order rivers

“…For example, in 2016, a simulated flood successfully mobilized bed sediments and reduced willow cover, which may have enhanced distribution of riparian invertebrate prey (Greenwood 2014) and foraging capabilities of bats (Hagen and Sabo 2012). Wetland inundation is also associated with increased abundance and diversity of both terrestrial and aquatic invertebrates (Holmquist and Schmidt-Gengenbach 2019), and promotes the growth of wetland plants, which in turn provide cover for breeding birds and ready access to insect prey (van Oort et al 2015). Our results suggest that current reservoir management practices that include managed scouring floods and floodplain inundation in at least some years may be sufficient to support aquatic-terrestrial food webs leading to birds and bats, with an effect comparable to the unregulated river.…”

Ants (Hymenoptera: Formicidae) as surrogates for epigeic arthropods in Northern Andalusian ‘dehesas’ (Spain)

“…In the case of the rest of the arthropods, they were identified to order level (except for subclass Acari) and the number of traps occupied by each one was recorded. Numerous studies have shown that the estimation of the diversity of arthropods at the taxonomic level of order can be a very useful tool for the evaluation of the conservation status of different ecosystems (Wettstein & Schmid, 1999;Cecil et al, 2019;Holmquist & Schmidt-Gengenbach, 2019).…”