There’s no doubt that our montane communities are already experiencing the effects of climate change. There is strong evidence that climate change is occurring sooner and at a faster rate at higher elevations. There are now hundreds of studies (e.g., here) that have already documented these effects: animals and plants are moving upslope and towards the poles following their preferred moisture and temperature regimes. On average each decade, the core range of montane species, worldwide, are shifting upslope 11 m and northwards 17 km. For example, over 40 years in the Green Mountains of Vermont, the boundary between the northern hardwood forest and the high-elevation boreal forest has shifted upslope 100 m.
Given that many montane bird species’ are largely restricted to higher elevations, we can reasonably expect these species to experience the effects of climate change sooner and more substantially than species whose core populations exist at lower elevations. Over the next few hundred years, quantitative ecologists predict that climate change will greatly diminish existing spruce-fir forest stands in the US by more than 50% (see here and here). Recent climate and species distribution modeling also predicts that northward range shifts within the next 100 years will result in our northeastern region no longer hosting sizable breeding populations of Blackpoll Warbler, Pine Warbler, Yellow-bellied Flycatcher, Magnolia Warbler, White-throated Sparrow, Ruby-crowned Kinglet, Red-breasted Nuthatch, Evening Grosbeak and many other familiar species.
To conserve and effectively manage our montane bird species we must, as a very first step, track how the distribution and abundance of these populations change through time and with respect to biotic (e.g., forest composition) and abiotic (e.g., climate and elevation) factors.
With this evolving report, we try to answer one seemingly simple question: what is the state of the mountain birds of the northeastern United States? Using long-term data collected by citizen scientists working on the Vermont Center for Ecostudies’ Mountain Birdwatch project, we have created indicators of population health for each species that we monitor. These indicators reveal which species are thriving and which may be in need of our help. In doing so, we seek to understand where our conservation efforts have succeeded and where they have not. Where we have fallen short in our efforts to protect the birds of our mountains, we suggest solutions.
This report is also a chance to celebrate the hundreds of citizen-scientists who each year venture out in the pre-dawn darkness to count birds in the high country from the Adirondacks of New York to Maine’s Katahdin. Their hard work and dedication allow us to gain unique insights into population trends of iconic species like Bicknell’s Thrush and Blackpoll Warbler and into the health of the mountain forests on which these birds depend. As we demand more and more from our mountains – as sites to generate renewable energy, as a source for clean water, and as places for recreation – this kind of information will prove increasingly important. Keeping mountain ecosystems healthy and productive in the face of climate change and increased use by humans requires science-based solutions, and science-based solutions require the sort of data collected under Mountain Birdwatch.
Why Mountain Birds Matter
They are a unique part of our natural heritage.
The birds of our high mountains – from the Adirondacks of New York across the northern Appalachians to Maine’s Katahdin – are mostly boreal species at the far southern extent of their range. One species, however, lives only on these mountains, and nowhere else: Bicknell’s Thrush. All of these birds find a home in the islands of spruce and fir that rise from the sea of temperate hardwood forests below. Together, they make up an entirely unique piece of our natural heritage, just like the Grand Canyon or the Everglades.
They are bellwethers of change.
Our mountain forests are valuable. Among other things, they provide us with clean water, free flood control, and a beautiful setting in which to play and to enjoy nature. Our mountain forests are also at grave risk from climate change. Documenting and understanding how climate change is affecting these forests is important, both as an act of bearing witness and in the hopes that we might learn how to minimize the effects. Tracking populations of mountain birds is an effective and efficient way of doing so: birds are sensitive indicators of environmental change and are relatively easy to study.
They are a source of joy and inspiration.
Sitting atop a mountain at sunrise, listening to the dawn chorus of bird song, provides for many people a visceral connection to one of our region’s last truly wild landscapes. These birds are icons of our mountains, and those special places would not be the same without them.
They attract visitors to our region.
Mountain birds also matter for practical reasons. Birders spend substantial amounts of money for the chance to see and hear the birds of our mountains, especially Bicknell’s Thrush.