At a time when the US Congress is divided on whether climate change even exists, the Massachusetts Audubon Society is making plans on how to adapt to it. Their problem is that climate change emperils their nature sanctuaries. They own 34,000 acres of land in the state, about 0.5% of the total, making them one of the state’s largest private landholders. The Commonwealth itself only owns 4%. Their forests are meant to be preserved as habitats for various bird and animal species, but as the forests change, the animals inevitably will too.
Tom Lautzenheiser writes about this here in the Fall 2010 issue of their magazine Sanctuary. He points to videos like this one, showing how spruce forests have migrated across the continent since the last Ice Age, as determined by pollen counts. The global temperature was about 8 deg C less then, and we’re looking at an increase of about 6 deg C in this century, according to the IPCC, and who knows what beyond that.
The Society has been carefully selecting what areas to preserve based on what the species balance looks like today, but that balance is going to shift radically in the next few decades. All their work will be for nought. They can hardly move the boundaries of their preserves to match the movement of the ensembles. Pleasant Valley, for instance, is all American chestnuts today, but could be full of tulip trees in another few years.
What to do? Lautzenheiser suggests picking preserves based on diversity of geography instead of present-day species ensembles. If the preserve has a variety of landscapes – deep valley, hillside, and plain – within it, there will always be a range of ecologies within it. Some fragment of the animal species we want to preserve will be able to survive somewhere within it. It’s equally important to build connections between preserves, so that species can migrate along protected paths. The goal is to maintain some resilience to the changes that are sweeping upon us.
Well that’s nice, you might say, but shouldn’t they be more worried about one particular species, namely us? If climate change is going to be drastic for chestnut trees and robins, isn’t it going to be worse for us? Well, yes, actually. But that’s not their job. They’ve been working on nature preservation for 116 years now, and expect to be doing it for centuries to come. They’re taking the long view, even if the politicians aren’t.