I, too, thank Joan McAlpine for this important debate. I agree that the Scots pine is, indeed, a magnificent tree—in fact, I have a couple in my garden.
I am the species champion for the red squirrel—unfortunately, I have none of those in my garden—and the expansion of our Caledonian pinewood forests offers hope for the species from the threats that contribute to its decline. Red squirrels were once a common sight across the UK, but they have been in decline for decades. Scotland is home to 75 per cent of the estimated 121,000 reds that are left. Non-native grey squirrels are a major threat and are capable of arriving in an area and wiping out the native population of reds in as little as 15 years. They do this by spreading squirrel pox, which is a virus that is fatal to reds but not greys.
Reds can also be affected by habitat isolation. In broadleaf woodlands, grey squirrels have the advantage of being able to process tannins in food sources such as acorns earlier in the year, helping them to out-compete the reds for food and territory. However, the reds do not suffer that disadvantage in Caledonian pinewoods and have a much greater chance of establishing populations there.
At the moment, the isolation of many Caledonian pinewoods can leave red squirrels isolated with limited ability to face challenges like fluctuations in food availability or climate change. Very small sparse patches of ancient Caledonian pine forest are not great for red squirrels; the canopies are so open and unconnected that squirrels often do not use them, and moving across heathery ground exposes them to too great a risk from predators. Connecting the pinewoods will give red squirrels greater ability to develop strongholds and cope with difficult times, particularly by allowing reds to look for alternative sources of food and move across landscapes to seek the best shelter in the harshest weather and by increasing breeding opportunities to help with recovery from periods of low population.
Trees for Life and the Woodland Trust Scotland are currently running the Caledonian pinewood recovery project—or CPR project, which is so appropriate—with advice and guidance from Scottish Natural Heritage and Scottish Land & Estates. A particular focus of the project is to work with private landowners and managers with what remains of the forest to identify the practical steps that are needed to first protect and then expand it.
As members said, the trees face particular challenges, such as being eaten by deer, disease and climate change.