This section provides a means to ensure continuation of a coherent legislative framework for the two Border rivers, applying consistently on both sides of the border.  This is considered necessary in order to ensure effective fisheries management for the river systems, including their tributaries.
Salmon and freshwater fisheries management on the Tweed is governed by the Tweed Fisheries Acts 1857-1969, which provide for a River Tweed Council, drawn from the Tweed Commissioners, with rules particular to the Tweed governing fishing and applicable throughout the whole Tweed river system, including the Tweed Box (an area of inshore sea at the mouth of the Tweed at Berwick).  In addition, certain provisions of Scottish public legislation governing salmon and freshwater fisheries also apply throughout the Tweed, even in England, and English fisheries legislation is disapplied.
For the Border Esk, fisheries management is governed in accordance with English legislation and Scottish legislation is disapplied, except for one provision (section 21 of the Salmon and Freshwater Fisheries (Protection)(Scotland) Act 1951) which makes it an offence in Scots law to take salmon illegally from the Esk in Scotland.  Management of the Esk fisheries is a function of the Environment Agency.
The Scottish Parliament is able to exercise jurisdiction over the matters covered by this section but only within Scotland: the Scottish Parliament is restricted by virtue of section 29(2)(a) from making laws which would form part of the law of England.  An Order in Council made under the present section enables common provisions to be made for the length of the Tweed and Esk Fisheries and to perpetuate the single fisheries regime which existed  for these rivers before devolution.
Fisheries management applies to all freshwater species, and also to salmon, migratory trout and eels, which are not solely freshwater fish.
Further provision about the making of subordinate legislation is to be found in sections 112 to 115 and Schedule 7.
Commentary Part V: Miscellaneous and General General