Monday, May 6, 2024

A Century of Change in Connecticut's Birds

John Hall Sage—an unknown name; unknown, long forgotten, even in his native Connecticut, and even though his contributions to the ornithology of his state were epic.  A founding member of the venerable American Ornithologists Union, its secretary for decades and even its president, he in an era in which quantitative was an alien term collected data—dates, locations, sexes, measurements, notes about the specimens he collected—hundreds of them, thousands even. 

And that is how I know him—from late at night, night after night and even into the early morning, in the bowels of the University of Connecticut’s collection room, amidst the overpowering scent of mothballs, alone with his catalogs, with his details about birds.  My fingers repeatedly brushed across his handwritten records, with hands holding the pages he had held, unfolding the notes he tucked among the pages, reading the records scrawled across the back of his daughter’s 1912 wedding invitation.  In this place of silent contemplation, he had become a friend of sorts, someone I knew, separated only by that troublesome quantity of time.  His catalogs spanned fifty years, and fifty years hence I learned from what he had learned as I prepared for my first season along his adored Connecticut River.  It was a place which it appeared had slipped into oblivion after his time, without any further long-term study of its inhabitants.  Likewise, his irreplaceable collection had been relegated to a basement where it sat ignored before being rescued just before I came to use it.  I have wondered if he considered whether anyone would again have the constitution to take up the quest he had begun. 

Now it is another fifty years hence as I prepare for my next season in that transcendent place, that singular landscape where, as it broods in the first breaths of an approaching day, time for a time suspends and its essence is returned to those whose tenure here far predate ours—those of bright voice, of exuberant constitution, of unparalleled loveliness.  When I began my studies, I somewhere wrote down that I would have to grow old to understand the sorts of questions that filled my head.  And, indeed, as old age and slipping vision envelops me, there does seem to be some inkling of an answer: much of what we think we know we don’t, what we see over the short term is illusion, the immutably integrated is not so but fluid.  The relationships, the interactions, all that we see, none of them remain the same.  As I also wrote to myself, the river I studied was rather an enigma, flowing continuously like time, taking what was new down its course, turning it from young to old, and then releasing it from material bonds.  From there, we cannot know what becomes of such things—once young, then old, and then free.

Sage in his collecting focused especially on the tidelands of the Connecticut River but he did not stop there.  He was as well intimately familiar with the birds dwelling within the limited tracts of forest present in Connecticut’s late nineteenth century landscape—the forest in all of its manifestations from early successional through mature.  He chronicled its birds, considered their distributions, their abundances, how these changed over the years of his observation and how what he saw fit into his friend C. Hart Merriam’s life zone concept.

So too, I realized that during my tenure I must do much the same.  By the beginning in the 1980s, I began to quantify using the techniques of the era how it was that the birds of the forest configured themselves.  I expanded my horizons by taking my forest studies to the other side of the planet before, by the beginning of the 2000s, I embarked on long-term investigations of forest birds throughout Connecticut, summer and winter, now fully a century since Sage’s initial work—work that encompassed tens of thousands of observations and tens of thousands of measurements.

A small subset of these measures examined a thirty-five-year span in an expansive managed forest in a region, corresponding roughly with the southern boundary of Merriam’s Canadian zone, with bird communities predicted to be particularly sensitive to the effects of climate change.  This work demonstrated that bird community changes indeed did show some relationships to Connecticut’s warming climate, but not always, and often trends were opposite to expectations.  Similarly, community change showed a fair number of connections with changing vegetation conditions—wildlife management 101—but not always and trends were often opposite to expectations. 

When using more sophisticated protocols over twenty years in Connecticut’s largely unmanaged, aging and more expansive Northeast Upland ecoregion, portions of which flirted with old growth conditions, these same sorts of patterns appeared, with changing climate and maturing forests appearing related to a good deal of bird community change, but again many of the changes were contrary to expectations.  Some of these contrary patterns might have been related to larger continental phenomena, but what I suspected most was that I was observing evolution in real time.  Species typically associated with successional landscapes were exploding into mature forests; those once associated with remote core forests were becoming lawn birds.  Species that at the beginning of my studies were absent were now the commonest birds in the forest.  Still others were inexplicably disappearing in conditions that should have favored them.  In short, nature appeared more complicated than we might wish it to be; it was a moving target.

Once some time back I took a private trip to Sage’s still stately home near the Connecticut River to seek out whatever of him might still remain there.  While sitting at that spot I said to him, just in case he might hear me, “John, you know, it’s just you and me.  I don’t know that anyone else would ever want to do this.  It’s too hard, the personal cost too great and I’m not sure that it matters much to anyone but us.  In any event, maybe in the not-too-distant future this is a conversation we can have together.  Until then, John, rest well.”

 

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