Bird4pop model for the simulation of foraging, dispersal and population processes of UK passerine birds
Gardner, E., Robinson, R.A., Broughton, R.K., Hinsley, S.A., Redhead, J.W., Woodward, I., Pywell, R.F., Bullock, J.M. (2024). Bird4pop model for the simulation of foraging, dispersal and population processes of UK passerine birds. NERC EDS Environmental Information Data Centre. https://doi.org/10.5285/985691ce-e66b-416a-bb85-fc9ad0eca6ed
Bird4pop is a process-based model, written in R, that simulates the foraging, dispersal and population processes of nidicolous passerines. It accounts for both amount and configuration of habitat resources to predict spatially-explicit relative abundance and foraging rates, for a given input landscape. The input landcover information must be in raster format. The model can ingest a base landcover raster as well as edgecover rasters, which represent the locations of small habitat features that occupy only a fraction of a pixel. Model outputs are raster stacks with the same spatial extent and resolution as the input landcover raster. The bird4pop model was co-developed by the UK Centre for Ecology & Hydrology and the British Trust for Ornithology. It has been parameterised for seven UK birds/bird groups (woodland specialists, woodland generalists, edge-nesting farmland birds, skylark (Alauda arvensis) – an open-nesting farmland bird, nuthatch (Sitta europaea) – a woodland specialist, robin (Erithacus rubecula) – a woodland generalist, yellowhammer (Emberiza citrinella) – an edge-nesting farmland bird). These parameter files (bird_guild_params.csv and bird_habitat_params.csv) are included. The model’s predictions have been validated against observations of these birds/bird groups collected across Great Britain through the BTO/RSPB/JNCC Breeding Bird Survey. Data in bird_guild_params.csv includes movement ranges (breeding season foraging range, juvenile dispersal range in meters), population growth parameters (nest density per ha, mean number of chicks produced per year, growth parameters in arbitrary units) and survival parameters (yearly adult survival probability, yearly juvenile survival probability) for seven birds/bird groups (woodland specialists, woodland generalists, edge-nesting farmland birds, skylark – an open-nesting farmland bird, nuthatch – a woodland specialist, robin – a woodland generalist, yellowhammer – an edge-nesting farmland bird), used in bird4pop model. Data in bird_habitat_params consists of scores representing the relative availability of suitable nest sites (on a scale from 0-1, where 0 = none and 1 = very high) and the relative availability of foraging resources during the breeding season (on a scale from 0-5, where 0 = none and 5 = very high) for four bird groups (woodland specialists, woodland generalists, edge-nesting farmland birds, skylark – an open-nesting farmland bird) and the 78 landcover classes, used in bird4pop model. Given scores are the mean values across n contributing experts. The data also include the number of contributing experts, the standard error on the mean score, and the alpha and beta values that describe a beta distribution consistent with the measured mean and variance for each score. This model is intended to help support understanding of how birds might be using landscapes. No decisions should ever be made solely on the basis of this model’s predictions – on-the-ground ecological surveys and integration of local knowledge are always required before any landscape-level or site-level decisions are made, due to real-life bird activity levels potentially differing from predicted levels. Users are recommended to get in touch with the model developers to ensure they have the most up-to-date version of the code and to receive support on model use and interpretation.
Bird4pop model code was developed from the poll4pop model (Gardner, et al., 2020; Yclough, 2020). It contains functions that are identical to those used in the poll4pop model, functions that are adapted from functions used in the poll4pop model, and new functions. Data in bird_guild_params.csv is derived from literature data, with subsequent processing to convert units and calculate guild-level values. The growth parameters are set by selecting the values that best reproduced observed responses of woodland specialist birds to habitat fragmentation. Data in bird_habitat_params is derived from an expert opinion questionnaire completed by four researchers. The mean scores and their standard error are weighted according to the self-reported certainty scores that experts gave alongside their habitat resource scores.
NERC EDS Environmental Information Data Centre