Spring bird survey data for Naree-Yantabulla from 2018 to 2023
Description
Data matrix of 133 variables (bird species) and 2,848 samples (site by year means). Each species is assigned to a foraging guild based on their principal food (carnivore, frugivore, generalist, granivore, herbivore, insectivore, insectivore-nectarivore, nectarivore) and a movement group (local, local-partial migrant, migrant-nomadic, Eyrean local, Eyrean nomadic) using Australian Bird Data Version 1. An additional classification of Eyrean vs Non-Eyrean was added to the movement groups. Eyrean species are identified as autocthonous to or centred in the Australian arid zone.
Files
Steps to reproduce
A team of volunteers conducted bird surveys annually in spring from 2018 to 2023. The survey method used was the “embedded” method used by Birdata, the database of BirdLife Australia. Surveyors worked in pairs. Each day, each pair of surveyors was allocated a cluster of 4, 5 or 6 sites. Site clusters were selected to minimise travel time between surveys. The first survey of each day commenced at local sunrise. The order in which sites were visited was varied to reduce the effects of time of day. At each site, one surveyor conducted a 20 minute survey identifying and counting all birds seen and/or heard within an 80 m radius of the site centre but not including birds flying over unless they were foraging within the site. This was designated the “inside” survey. The aim of the inside surveys was to obtain accurate count data for the species detected. Simultaneously, the other surveyor conducted a 20 minute search within 500 m of the site centre but not including the inside site and trying to target the same habitat type as the inside area. This was designated the “outside” survey. The aim of the outside survey was to detect as many species as possible. At the end of 20 minutes, surveyors swapped roles and a second survey was conducted at the same site. Using this survey design, sites had two x 20 minute inside surveys plus two outside surveys conducted on a given survey day. In each survey campaign, every site was surveyed once by every surveyor, although the numbers of surveyors varied and in some years it was not possible to access all sites. Repeat surveys were intended to account for differences between observers and variation in bird activity between days. Data were combined to calculate mean abundances for each species for each site for each year. Only data from the inside surveys were used in statistical analyses.