The river is of high biodiversity value and is both a Site of Special Scientific Interest (SSSI) and a Special Area of Conservation.
The SAC designation notes the river's importance for salmon (Salmo salar), otters (Lutra lutra), brook lampreys (Lampetra planeri), river lampreys (Lampetra fluviatilis), and sea lampreys (Petromyzon marinus).
The Tay also maintains flagship population of Freshwater pearl mussel (Margaritifera margaritifera).
Freshwater pearl mussels are one of Scotland's most endangered species and the River Tay hosts two-thirds of the world's remaining stock.

The Tay is internationally renowned for its salmon fishing and is one of the best salmon rivers in the United Kingdom, and western Europe, attracting anglers from all over the world.
The lowest ten miles of the Tay, including prestigious beats like Taymount or Islamouth, provides most of the cream of the Tay.
The largest rod caught salmon in Britain, caught on the Tay by Miss Georgina Ballantine in 1922, weighing 64 pounds (29 kg), retains the British record.
The river system has salmon fisheries on many of its tributaries including the Earn, Isla, Ericht, Tummel, Garry, Dochart, Lyon and Eden.
Dwindling catches include a 50% reduction in 2009 so the Tay District Salmon Fisheries Board ordered a catch-and-release policy for females all season, and for males until May, beginning in the January 2010 fishing season.
Research by the North Atlantic Salmon Conservation Organisation has shown that the number of salmon dying at sea has doubled or trebled over the past 20 years, possibly due to overfishing in the oceans where salmon spend two years before returning to freshwater to spawn.
The widespread collapse in Atlantic salmon stocks suggests that this is not solely a local problem in the River Tay.

A section of the Tay surrounding the town of Dunkeld is designated as a national scenic area (NSA), one of 40 such areas in Scotland, which are defined so as to identify areas of exceptional scenery and to ensure its protection by restricting certain forms of development.
The River Tay (Dunkeld) NSA covers 5,708 ha.

The first sustained and significant population Eurasian beaver (Castor fiber) living wild in Scotland in over 400 years became established on the river Tay catchment in Scotland as early as 2001, and has spread widely in the catchment, numbering from 20 to 100 individuals in 2011.
These beavers were likely to be either escapees from any of several nearby sites with captive beavers, or were illegally released, and were originally targeted for removal by Scottish Natural Heritage in late 2010.
Proponents of the beavers argued that no reason exists to believe that they are of "wrong" genetic stock.
In early December 2010, the first of the wild Tayside beavers was trapped by Scottish Natural Heritage on the River Ericht in Blairgowrie, Perthshire and was held in captivity in Edinburgh Zoo, dying within a few months.
In March 2012 the Scottish Government reversed the decision to remove beavers from the Tay, pending the outcome of studies into the suitability of re-introduction.

As part of the study into re-introduction, a trial release project was undertaken in Knapdale, Argyll, alongside which the population of beavers along the Tay was monitored and assessed.
Following the conclusion of the trial re-introduction, the Scottish Government announced in November 2016 that beavers could remain permanently, and would be given protected status as a native species within Scotland.
Beavers will be allowed to extend their range naturally.
To aid this process and improve the health and resilience of the population a further 28 beavers will be released in Knapdale between 2017 and 2020, however there are no plans at present to release further beavers into the Tay.
The river is of high biodiversity value and is both a Site of Special Scientific Interest (SSSI) and a Special Area of Conservation. The SAC designation notes the river's importance for salmon (Salmo salar), otters (Lutra lutra), brook lampreys (Lampetra planeri), river lampreys (Lampetra fluviatilis), and sea lampreys (Petromyzon marinus). The Tay also maintains flagship population of Freshwater pearl mussel (Margaritifera margaritifera). Freshwater pearl mussels are one of Scotland's most endangered species and the River Tay hosts two-thirds of the world's remaining stock.
The Tay is internationally renowned for its salmon fishing and is one of the best salmon rivers in the United Kingdom, and western Europe, attracting anglers from all over the world. The lowest ten miles of the Tay, including prestigious beats like Taymount or Islamouth, provides most of the cream of the Tay. The largest rod caught salmon in Britain, caught on the Tay by Miss Georgina Ballantine in 1922, weighing 64 pounds (29 kg), retains the British record. The river system has salmon fisheries on many of its tributaries including the Earn, Isla, Ericht, Tummel, Garry, Dochart, Lyon and Eden. Dwindling catches include a 50% reduction in 2009 so the Tay District Salmon Fisheries Board ordered a catch-and-release policy for females all season, and for males until May, beginning in the January 2010 fishing season. Research by the North Atlantic Salmon Conservation Organisation has shown that the number of salmon dying at sea has doubled or trebled over the past 20 years, possibly due to overfishing in the oceans where salmon spend two years before returning to freshwater to spawn. The widespread collapse in Atlantic salmon stocks suggests that this is not solely a local problem in the River Tay.
A section of the Tay surrounding the town of Dunkeld is designated as a national scenic area (NSA), one of 40 such areas in Scotland, which are defined so as to identify areas of exceptional scenery and to ensure its protection by restricting certain forms of development. The River Tay (Dunkeld) NSA covers 5,708 ha.
The first sustained and significant population Eurasian beaver (Castor fiber) living wild in Scotland in over 400 years became established on the river Tay catchment in Scotland as early as 2001, and has spread widely in the catchment, numbering from 20 to 100 individuals in 2011. These beavers were likely to be either escapees from any of several nearby sites with captive beavers, or were illegally released, and were originally targeted for removal by Scottish Natural Heritage in late 2010. Proponents of the beavers argued that no reason exists to believe that they are of "wrong" genetic stock. In early December 2010, the first of the wild Tayside beavers was trapped by Scottish Natural Heritage on the River Ericht in Blairgowrie, Perthshire and was held in captivity in Edinburgh Zoo, dying within a few months. In March 2012 the Scottish Government reversed the decision to remove beavers from the Tay, pending the outcome of studies into the suitability of re-introduction.
As part of the study into re-introduction, a trial release project was undertaken in Knapdale, Argyll, alongside which the population of beavers along the Tay was monitored and assessed. Following the conclusion of the trial re-introduction, the Scottish Government announced in November 2016 that beavers could remain permanently, and would be given protected status as a native species within Scotland. Beavers will be allowed to extend their range naturally. To aid this process and improve the health and resilience of the population a further 28 beavers will be released in Knapdale between 2017 and 2020, however there are no plans at present to release further beavers into the Tay.
River Tay