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Due to the high variability in bird counts in the freshwater estuarine zone, a higher degree of uncertainty is likely to be associated with the results, hence higher caution should be used when interpreting the results for this zone.
The analysis could be improved by taking into account not only the habitat availability in the immediate vicinity of the high water compression and roosting sites, but also the availability within a wider area, the size of this being determined based on the knowledge of the movements of the species between high water and low water sites.
The species-habitat distribution modelling should be extended to all the key species occurring in an estuary in order to identify their environmental needs in the local area. This will allow better prediction of the effects on estuarine use should the environmental conditions change (e.g. reduction in habitat availability, changes in water quality). It is of note that the validity of the model’s results is limited by the dataset used to create the model itself. Therefore a model developed based on data on a given estuary (or part of it, e.g. mesohaline and polyhaline zone only) could provide useful guidance for the management of the species in that estuary (or part of it) alone and should not be used as guidelines for other areas.
When using the results of species-habitat distribution models for management purposes (e.g. creation of suitable habitat for a species), attention should be given to the combinations of environmental conditions that are defined by the model as important in determining bird habitat use rather than in managing a single environmental factor alone. However, it is of note that environmental factors can be ranked based on their importance in affecting the species habitat use, hence priorities can be identified in the habitat management.
More comprehensive low water usage data sets would be of particular value in further defining key relationships between environmental variables and habitat utilisation.