Reservoir Fish Removal
May - June 2019
Fish removal from the reservoir using a multi-method approach, comprised of two phases, tasks undertaken included:
- Obtaining regulator consents to allow for removal to take place using seine netting and electric fishing (also referred to as electro fishing).
- Close liaison with client regarding reducing water levels to ensure fish welfare, catch efficiency and a safe working environment.
- Our skilled and experienced aquatic ecologists reviewed available bathymetry data and identified the need for a bespoke 100m x 6m specialist seine net was required to ensure high catch efficiency.
- Captured fish were quickly and safely transferred to tailor made catch cages for temporary holding.
- Fish were transported from temporary holding cages into oxygenated transport tanks.
- Fish transported in specialist oxygenated tanks to nearby suitable water body, where they were carefully released.
- Phase 2 consisted of primarily electric fishing as water levels were suitably lower and netting was unsuitable.
- Five Rivers were on hand to support the client with advice on best mitigation practice.
- A unique example, with very challenging environmental conditions, giving the project a great deal of character. Despite site constraints (deep silt, large rocks and access) fish capture was carried out safely in an efficient and timely manner, with a focus on fish welfare.
- Given the complexity of the dewatering, Five Rivers worked adaptively, and successfully to very high standards despite the changeable work programme of the clients and sub-contractors.
- Selection of methods during each phase undertaken by highly skilled aquatic ecologists.
- A range of different species were captured and removed, across various life stages, from small fry to large adults, indicating the comprehensive effectiveness of chosen methods in selecting for all possible fish sizes and species present.
- Successful mitigation of potential fish mortality associated with the works to be undertaken.
- Client satisfaction and assurance that work has been completed to the highest possible standard.
- Successful release of fish into new suitable environment