Hi Mike
Yes, I think I can help although I am not a member of the River Don Brown Trout Improvement Association (RDBTIA). The statutory opening day for brown trout is 15th. March for Scotland. However, proprietors, associations etc can and do set their own dates within the statutory period. In the case of the ADAA it sets 1st. April as the opening day for Brown Trout fishing on all its waters, whether catch and release is practiced or not. So no,you cannot fish ADAA waters after 15th March just because you practice catch and release you have to wait until 1st. April. Other proprietors may set different dates so it would be worth checking with the beat before wetting a line. I take the point on board however and will bring it to the attention of RDBTIA.
As regards Hamish's question the Trust and the Board, if appropriate, might enter an agreement with a developer to give approval for a development affecting the river and potentially its fish and ecology on the basis that the developer would have to carry out say enhancement works to the river or restocking if there was a fish kill or potential fish kill for example. This is called mitigation and is used to ensure that any development potentially affecting the river never leaves it in a poorer condition overall after the development takes place. So in this particular instance RDBTIA are saying if brown trout have to be stocked as a result of a mitigation agreement it has to be with river Don brown trout
I hope this helps clarify the position, if not let me know here or at iain@riverdon.org.uk.
Regards
Iain