Habitat Surveying.

Salmon parr

History - the KOSDSFB is currently undertaking a full audit of the freshwater habitat in the district for which we are responsible for. This is a very long term project, we have 70 miles of main river and 400 miles of tributary burns. We are looking at the head waters first, where our adult fish mainly spawn (spring element of the population), and where our juveniles grow. Also it must be remembered that whatever happens upstream will effect the area down stream. In time all the rivers will be surveyed in their entirety. We have been undertaking habitat work for the last three years.

Data collection - habitat surveys normally begin at the start of May. Work is not undertaken until this date because we need spring vegetation growth on the river banks (the riparian zone). The bank side vegetation is included in the survey work. We also look in detail at factors such as substrate (the make up of the bed of the river), flow rates, pollution (not much with us), vegetation types, fish cover and several other points. All habitat work is undertaken form a parr's point of view (fish cover etc). Each site is also photographed for future reference.

Use of Data - once the data has been collected in the field it is transferred to a data base. This data can then be used in a variety of ways. Maps can be drawn up to show different habitat values, for example cobbles, boulders, bed rock plotted against each other on a pie chart linked to a data point. Locations of sites and site codes can also be shown.

Another aspect of habitat data important from a fishery management point of view is assessing the "carrying capacity" of an area. This figure provides us with an idea of how many parr a stream can carry - or support. From this number we can estimate how many hatchery fish may be required for stocking in areas requiring hatchery intervention. We can also extrapolate a smolt output figure for a tributary using the technique.