Site vegetation characteristics are more important than landscape context in determining bird assemblages in revegetation

Abstract

The effectiveness of revegetation in providing habitat for fauna is expected to be determined both by within-site factors and attributes of the landscape in which a revegetation site occurs. Most studies of fauna in revegetation have been conducted in landscapes that have been extensively cleared, modified or fragmented, and in Australia, predominantly in the southern temperate zone. We investigated how within-site vegetation attributes and landscape context attributes were related to bird species richness and composition in a chronosequence of post-mining rehabilitation sites within an otherwise intact landscape in tropical northern Australia. Our working hypothesis was that bird species richness in rehabilitating sites would be positively related to site vegetation structure and landscape context including (1) proximity to woodland and (2) the proportion of woodland within a 500-m buffer of rehabilitation sites. Within each of 67 sites, we sampled vegetation once and surveyed for birds eight times over 16 months. Landscape context variables were calculated using GIS. There were large differences between bird assemblages of woodland and rehabilitation sites and between age classes of rehabilitation. Bird assemblages were strongly related to site vegetation attributes across all rehabilitation sites. Proximity to woodland was only related to bird assemblages in rehabilitation sites older than 4 years old. We conclude that the relative importance of landscape context and site variables at any point in time will be a function of how closely vegetation within the revegetation site matches the habitat resource requirements of individual species.

Bird Functional Traits Respond to Forest Structure in Riparian Areas Undergoing Active Restoration

“…Bird assemblages can show large shifts in their composition according to the vegetation successional stage [22][23][24][25]. In accordance, descriptors related to forest structure such as vegetation height, total basal area or canopy depth can explain the richness and composition of bird species in restored sites [26].…”

“…These species occur exclusively or preferentially in the forest interior, suggesting that their performance is directly related to tree size and density [4]. However, studies evaluating the responses of bird assemblages to forest restoration generally compare areas in restored vs remnant reference forests [28,29], classify areas in age classes [26,30], or use time since restoration as a continuous predictor variable [31,32]. Although these studies recognize the importance of vegetation structure on bird assemblages, few studies explicitly used the development of forest structure as a predictor variable.…”

Reclamation and habitat‐disturbance effects on landbird abundance and productivity indices in the oil sands region of northeastern Alberta, Canada

“…Vegetation structure is generally considered a stronger driver of avian habitat use than vegetation species composition or position of the reclaimed or disturbed habitat in the landscape (Brady & Noske ; Munro et al ; Gould & Mackey ). We characterized habitats at our MAPS stations on the basis of vegetative structure, following the habitat structure assessment protocol of Nott et al ().…”

Water availability drives aboveground biomass and bird richness in forest restoration plantings to achieve carbon and biodiversity cobenefits

“…Canopy cover and tree height have been found to be particularly important for woodland-dependent birds, and the presence of a shrub layer influences colonization by understorey-nesting birds (Barrett et al, 2008;Gould & Mackey, 2015;Munro et al, 2011).…”

“…Plant richness and vegetation structure are also known to influence bird diversity through provision of food and nesting sites, and protection from predators (Belder, Pierson, Ikin, & Lindenmayer, ; Bonifacio, Kinross, Gurr, & Nicol, ). Canopy cover and tree height have been found to be particularly important for woodland‐dependent birds, and the presence of a shrub layer influences colonization by understorey‐nesting birds (Barrett et al, ; Gould & Mackey, ; Munro et al, ). Older plantings support more bird species because more time has elapsed for species to colonize them, and because structural attributes for nesting and shelter have developed, such as large boughs and tree hollows (Kavanagh, Stanton, & Herring, ; Lindenmayer et al, ; Vesk, Nolan, Thomson, Dorrough, & Mac Nally, ; Whytock et al, ).…”