With a catchment size of over 3000km2 the Spey is the third largest river in Scotland. The length of all the river and burns total more than 36,500km providing a huge area of habitat for the wide range of species it supports. 732km of river/burn are accessible to migratory salmonids such as salmon and sea trout, providing over 11,000,000m2 of potential habitat.
The Spey is a large and diverse river with a wide range of habitat types, including mountain burns, forest streams and the wide fast flowing reaches of the lower river. The Spey supports the highest naturally occurring salmon population in Scotland with spawning occurring at 600m (2000ft) in both the Dulnain and Avon tributaries. The habitat at 2000ft elevation could hardly be more different from that found in the main stem of the lower river, however fish such as salmon and trout are highly adaptable and they will utilise any accessible habitat.
Habitat quality is crucial particularly for migratory species such as salmon which relies on and utilises such a wide range of habitats during its life cycle. With marine survival of salmon declining over the last few years it is imperative that we ensure that habitat quality throughout the Spey is a good as it can be in order to maximise smolt production. Whilst it is considered to be one of the best quality rivers in Scotland the Spey has been subject to considerable modification and there are few areas where the habitat is truly pristine. Much of the upland forest cover has disappeared and a high proportion of the water in the upper catchment is abstracted for hydro generation outwith the Spey. Along the length of the mainstem and tributaries side channels have been cut off or meanders straightened, simplifying and reducing the area of available habitat. There is a great deal of good quality habitat in the many Spey burns but significant areas require to be fenced to exclude farm stock so that bankside cover can regenerate.
In the lower river invasive species such as giant hogweed, japanese knotweed, white butterbur and ranunculus are modifiying and changing the riparian and instream habitat, often to the detriment of native flora and fauna.
It can be seen then that even in a high quality river such as the Spey habitat management is a huge issue. The Spey Fishery Board works with a wide range of partners, from regulatory agencies such as SEPA and SNH, to individual farmers and estates to ensure that best practise is encouraged and habitat improvements are implemented whenever possible.