This week here in Maine we had a major push of Boreal migrants through the state. On Wednesday night a friend and I listened as nocturnal calls of southbound migrants rang out from above the house at a rate of six per minute. That’s about 360 bird calls per hour or about 2800 over the course of a night and that’s just from one small location. Imagine how many birds must have migrating that night if the migration wave extended from Chicago to Maine? We heard many Swainson’s Thrushes and lots of warbler calls that certainly would include species like Blackpoll, Bay-breasted, Magnolia Warblers and many others. At the same time as these birds were migrating south, two scientific papers came out that have important implications for the future of Boreal birds.
A paper that appeared in the journal Nature, clearly demonstrated that protecting the remaining intact, mature Boreal forests is essential for combating global warming. Why? Because the author’s careful analysis of previously published studies showed that forest ecosystems continue to sequester lots of carbon even as they become old. This counters a widely held but never well-supported belief among some quarters that it might be better to cut down old-growth forests in order to replace them with fast growing young forests because the young forests suck up lots of carbon. Not true, as the authors of this study document.
The Canadian Boreal contains something like 25% of the remaining intact, untouched forest on the globe. We now know that protecting large swaths of it is vitally important for continuing to lower the levels of carbon in the atmosphere that are causing global warming.
That could be good news for birds.
Another paper that was recently published has documented the severe decline of a Boreal breeding species and popular backyard feeder bird, the Evening Grosbeak. The paper points out that the highest densities of breeding Evening Grosbeaks occur in the oldest forests and current levels of forestry in the Boreal are not only reducing the age of forests but are also making them all of the same age (that is, there is less diversity of different age classes). The dramatic drop of Evening Grosbeak numbers may be a result, at least in part, of the legacy of industrial forestry in the southern Boreal.
For the Evening Grosbeak and many other old-growth forest loving Boreal birds, letting policy makers understand that protecting intact Boreal forest is part of the solution to fighting global warming as the Nature paper did, could be the factor that allows them to have the habitat that they need to survive and thrive.
Now that Ontario has led the way with its recent announcement of its plans to protect 55 million acres of these carbon-eating Boreal forests, maybe other provinces will see that they can make a global commitment to helping a global problem by protecting 50% of their Boreal forests.