Invasive Species
Fish Diseases
There are a variety of different diseases which affect Salmon, with some being in freshwater such as saprolegnia, and some in the marine environment such as sea lice. Anglers should take care when fishing aboard, as some parasites like Gyrodactalus salaris are very hardy and can survive for several days in damp conditions. The risk of bringing diseases such as this to Scottish rivers can be mitigated by thoroughly cleaning your equipment, using a chemical disinfectant such as iodine or preferably virkon, and letting your gear dry for 48 hours.
Farmed Salmon
Pests and diseases such as the “Fish Louse” cause extensive suffering, and even death of fish and can lead to fishery closures.
Invasive Aquatic Species
Floating Pennywort – This plant can grow up to 20cn a day! Look out for its shine leaves with a crinkled edge.
Zebra Mussel – A very small freshwater mussel (2-4cm long) which can alter whole ecosystems by forming dense colonies and filtering vast amounts of water.
Killer Shrimp – The large shrimp (up to 3cm) is a voracious predator of other invertebrates and can survive up to 15 days in damp conditions.
Invasive river bank plant species
Some plants have proved highly invasive, colonising a habitat often to the detriment of native species and habitats. Once established they are very difficult and costly to eradicate or control.
Giant Hogweed – This monster plan can grow up to 12 feet high. It grows mainly along river banks and burns, shading out the native vegetation and leads to bank erosion and the sap of this plant can cause skin burns. Repeated and coordinated spraying with herbicide is the best control method.
Himalayan Balsam – This river bank plant is an annual and shades out native ground plants. It has explosive seed pods that shoot the seeds a few metres from the plant onto the ground or into the river. This mean it can spread rapidly. Simple control measures of pulling this plant up by the roots is very effective and after a few years can be eradicated.