The Osprey

The UK is still missing many of its former species, such as lynx and wolves, but there are some species that have been successfully restored. The osprey is one of British conservation’s success stories, and it has been led by Trees for Life’s patron, Roy Dennis.


The osprey (Pandion haliaetus) is a relatively large bird of prey that grows up to one metre in length. It inhabits a variety of habitats and is found on every continent except Antarctica. Ospreys feed solely on fish, which they take from lakes, rivers, estuaries and coastal waters. They are a migratory species and every year British ospreys carry out a remarkable 3,000 + mile migration from their wintering sites in Africa to return to the UK to breed.

The need for restoration

The osprey was once widespread throughout the UK but, due to severe persecution from the Middle Ages onwards, numbers plummeted. In the 19th century a new threat appeared, in the form of egg collectors and, by the end of the 19th century, only a handful of breeding pairs remained. A conservation programme was initiated and, thanks to a combination of long-term protection and innovative restoration techniques, the osprey is once again established in stable numbers in the UK.

How was restoration achieved?

From one breeding pair at Loch Garten in 1954, the UK osprey population has grown to an estimated 300 pairs today, through the following conservation measures:

Nest protection

As with many birds of prey, egg collection and destruction of nest sites has been a serious threat. In the early days of osprey restoration it was necessary to surround the trunks of some nest trees with barbed wire, to prevent thieves reaching the eggs. Keeping the location of nest sites secret and monitoring the number of eggs and chicks at all known sites has been integral to increasing osprey numbers.


Ospreys are semi-colonial, meaning that they prefer to nest near other breeding ospreys. They also exhibit strong natal nest-site fidelity, meaning that young ospreys breeding for the first time will return to the area where they were reared to search for a nest site. So although there may be excellent habitat throughout the country, this will normally be ignored unless there are already other ospreys there. For this reason, colonisation can be very slow without human intervention.

In 1996 Roy carried out a pioneering translocation to Rutland Water, in Leicestershire. Artificial nests were built and 64 chicks were translocated from Scotland over a period of five years. The chicks were artificially reared in cages, with human contact kept to a minimum, and then released to set off on their first migration. It has proved a great success, with chicks returning to Rutland to breed, and there is now an established population there which has also led to the colonisation of Wales.

Ospreys in the Trees for Life Project Area

We are lucky enough to regularly see ospreys in our Project Area. Forestry Commission Scotland have built a number of artificial nests which have been used, and the pair which we see most frequently, in Glen Moriston, have recently built a new nest after using an artificial one for several years. This pair fish on the River Moriston, just next to our Dundreggan estate, and we hope that they manage to successfully rear chicks this year, after hatching eggs last year but then losing the chicks due to bad weather, as occurred at many local nests.

In the Highlands, Scots pines are by far the trees most frequently selected for nest sites, so the work that we are doing in planting this species throughout our Project Area will expand the area of habitat available for breeding ospreys, and enable them to return to areas that would likely once have been ancestral nesting territories.

Although UK numbers are still only about one tenth of what they should be, the restoration of the osprey in Scotland can be viewed as a real conservation success story. Despite humans being the cause of the osprey’s decline, we have also been able to bring about its restoration. This proves that with good, species-specific conservation measures, we can successfully bring back wildlife that has been lost, and gives hope that one day we will be able to successfully reintroduce some of our other missing species.

Becky Priestley

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