Skip to content

Walkover Surveys

Habitat assessment and evaluation is a key element of managing a fishery and recording changes and impacts.

These can be used at a local level to identify areas for improvement work and maintenance, but can also identify specific impacts such as barriers to migration and on a catchment scale, issues such as land-use and farming practices that may be impacting on the fishery.

The Water Framework Directive requires that our rivers and surface waters are of good ecological status, and walkover surveys can be a very useful tool to identify areas and issues that may be preventing good status being achieved.

The following standard methodology is used in order to obtain consistent and comparable results. Every effort is made to record information accurately under favourable river conditions; for example normal river levels with good/excellent visibility, two members of staff carry out the surveys and an agreement made where the information collected is subjective.

The standard method involves dividing the river corridor into 300m sections, which are then walked by two members of staff in either an up or down stream direction. A ten digit GPS reference is taken at the upstream and downstream point on each section, and a minimum of one photograph taken which is representative of the habitat.  Any significant structures, discharges or impacts are also photographed.

A data sheet is completed for each 300m section and spot checks are undertaken at regular intervals throughout the section to allow a detailed map to be constructed, and an end of section summary check list completed to minimise the chance of data collection errors.  Data collected is then entered into Microsoft Excel spreadsheets to summarize the findings and allow meaningful interpretation of the information collected.  It also provides a clearer picture of the combined results where a number of sections may be impacted by the same factors.

The raw data sheets form a detailed reference library for each section and can be used to provide specific details where works or improvement schemes are proposed.

Casterbridge Fisheries has a qualified team of habitat assessors and recent examples of our work include the River Frome and Piddle habitat Assessments 2010. Please click here >>

We are an established company, specialising in all aspects of water, fishing and fishery management