The main habitat modelling and mapping methodology used by the HABMAP project was developed in conjunction with marine scientists at ABPmer. The HABMAP habitat model is geographical information system based and uses the strength of the association between ecology (biotopes) and the physical environment (water depth, salinity, sediment type, bedforms, bed shear stress, temperature and light attenuation). For each biotope the model assesses the range of each of the physical factors (e.g. depth 10-50 m, salinity 34-35 ppt etc). The model then identifies other areas with matching physical parameters to predict possible occurrences of the biotope in areas where the biotope has not so far been recorded. Therefore maps can be created for each biotope showing areas where the biotope is known to occur and areas where the biotope is predicted to occur.

For each subtidal biotope recorded in the HABMAP area we have maps showing the actual and predicted distributions. We have also assessed the confidence in the predictions. Our final GIS dataset lists the recorded and predicted biotopes in each polygon in order of confidence. These datasets are available from the downloads section.

The figure on the right is a biotope map for the seabed off the north west of Anglesey and shows the data underlying the map for the polygon with dark blue hatch shading (BIOTOPE1= the biotope code for the most likely biotope, PRESENCE1=whether the biotope has been recorded in that polygon (present) or has been predicted to occur (predicted), RESULT1= confidence score, BIOTOPE2= the biotope code for the second most likely biotope etc).

For more details download the modelling chapter from the HABMAP report.