creating environmental improvements through biodiversity

SAFEGUARDING MINERAL EXTRACTION SITE RESTORATIONS
NEAR AIRPORTS: DEVELOPING AN OBJECTIVE BIRDSTRIKE RISK
ASSESSMENT MODEL FOR HAZARDOUS WATER BIRDS – AN AID FOR
ENVIRONMENTAL ASSESSMENT POLICY (MIRO SAMP, DCLG, CSL)
(Justin Hart, Alison Colyer, Andrew Robinson, Paul Cropper, Pawel Plonskier, Lisa Allen, Mark Brown, Richard
Budgey, Mark Parnell, John Allan (Central Science Laboratory Bird Management Unit)
September 2007
Project Type: Bird counts, radio telemetry, radar detection of birds, site assessment / measurement,
mathematical modelling
Site: Birds counted and parameters measured at 256 restoration sites in north, midlands and south of
England. Additional data from 97 of these sites. Morphological features from 26 restoration sites in upper
Thames Valley used as predictors of radar tracked bird movements
Project Aim: To define a series of mathematical procedures that can be used by the minerals industry and
safeguarding authorities to predict likely abundances and movements of hazardous birds at new restorations.
To identify a series of models that could be used predictively and then determine their utility for safeguarding
purposes.
Main Methods:
Fieldwork:
Bird counts at restoration sites, of species considered most hazardous to aircraft
Measuring physical parameters of restored sites – area of open water, perimeter length, sinuosity, region,
presence of islands, number of islands, number of adjacent pits (in clusters of gravel extraction sites),
morphology of adjacent pits
Measuring additional parameters at 97 of these restorations – habitat diversity (number of habitat types at
each site, defined using Phase 1 Habitat Survey methods); area of islands; reed abundance; presence of short
grass, fish stock and rafts; water chemistry; site usage and public access
Radio telemetry – of wigeon, Canada geese and mallard (with conventional radio tags rather than satellite
tracking)
Radar:
Use of CSL’s bird detection radar to track bird echoes, (as used in earlier CSL report - Walls and Brown,
2004), and data saved to Microsoft Access database. Tracks plotted using ArcGIS 9.1 (ESRI 1999) to facilitate
analysis of bird flight lines
Range Analysis:
Radio tracking data analysed for eight wigeon using minimum convex polygon analysis – sufficient data
obtained to do this for only these birds
Mathematical modelling:
Use of two subsets of collected data on site features to model the bird counts: GIS derived features for all
256 sites; and data from the first subset plus additional parameters, for the 97 sites where additional data was
collected
Use of measured parameters as explanatory variables in linear mixed effect regression models that described:
abundances of all water birds; specific abundance of dabbling duck, diving duck, diving species, grazing species,
piscivores, geese and gulls; and abundance of mallard and tufted duck; in non-breeding and breeding seasons
Multi-modal inference, and estimation of how well each model fitted with the data, to use in selecting the
models that could best be used as predictive tools
Sustainable Aggregates Creating Environmental Improvements through Biodiversity
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