North American Birds

VOLUME 69 NO3 2016

A Quarterly Journal of Ornithological Record Published by the American Birding Association. The mission of the journal is to provide a complete overview of the changing panorama of our continent’s birdlife.

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Figure 18. These three juvenile Ospreys were raised along the North Platte River, Scotts Bluff County, Nebraska, the nest here photographed 25 July 2015. This is one of three or four successful Nebraska nests in 2015, the first year this species had bred successfully in the state. Photograph by Kathy DeLara. V O L U M E 6 9 ( 2 0 1 6 ) • N U M B E R S 3 / 4 353 T H E C H A N G I N G S E A S O N S : R E T R O S P E C T will be invading exotics from farther south: Scaly-breasted Munias, for instance, now established locally in the Yucatan Peninsula (Figure 17), Florida, Texas, and California, were documented nesting for the first time this season in Alabama (regrettably, in Purple Martin houses). It could well be that warmer temperatures are conducive to the conquest of more states in the Southeast in years to come. As Michael McKinney and Julie Lockwood wrote back in 1999: "Emerging evidence shows that most species are declin - ing as a result of human activities ('losers') and are being replaced by a much smaller number of expanding species that thrive in human-altered environments ('winners'). The result will be a more homogenized bio- sphere with lower diversity at regional and global scales." Good news Our tendency to focus on declining popula- tions of passerines, shorebirds, seabirds, rap- tors—certainly, the majority of our nesting species in North America—leads us to forget that not every species is in decline. Consider that in 1996, Oregon recorded its second certain record of Short-tailed Albatross; now the state has at least 14 records, a testimony to faithful stewardship by conservation- ists on the nesting grounds. Twenty years ago, the second record of Bermuda Petrel for North America came through, and now of Nazca Booby in the United States (Figure 14), which could well be an expected (if still rare) species during El Niño years off Mexico and southern California and indeed could increase if prey resources are disrupted in years to come. Tropical Kingbird is a staple of the au- tumn reverse-migrant season on the Pacific coast, but more recently, the species has been documented nesting in Florida and has shown a tendency to turn up far out of range in summer: northern Texas, Illinois, Penn- sylvania, even Québec and now Minnesota (Figure 15). What is to prevent this species from becoming a nesting bird well north of current southern-tier range, if we see hot summers with abundant insects and other food available for tyrant flycatchers, as with the documented expansion of Scissor-tailed Flycatcher, both as vagrant and nester? Could some "species of concern" benefit from the warming planet in the near term? Records of overshooting and/or pioneer- ing Swainson's Warblers (Figure 16) have been on the slow rise in the past decade, and though their expansion would seem to be limited by available habitat, their ability to nest in montane Rhododendron thickets as well as southerly swampwoods suggests some flexibility. We can only hope that there is a silver lining for some of our birds in years to come. Surely, though, for every hopeful, singing Swainson's Warbler, there sion of vagrancy, although the phenomenon may be more akin to periodic altitudinal mi- gration." He offers as a case in point several Berylline Hummingbirds that were noted on the Caribbean slope of Honduras in May (Figure 13). At least some hummingbird aficionados have offered the suggestion that our vagrant hummers in some cases could be drought-stressed birds seeking flowers and insects in new areas far from core range. If this is the case, then we would expect to see more vagrancy in the future, in which severe droughts are forecast to become more frequent. Looking forward: 2036 Where will birds, and birding, be in twenty more years? A cover of Birding magazine by Michel Gosselin in 1981 showed a futuris- tic birder laden with automated recording year; but the Dick Tracy comic strips came closer to accurate for modern birding, with most everything we need (except binocular and scope) now electronic and miniaturized. The trend toward automation in our bird- ing shows every sign of increasing, such that human-free birding (bird surveys done by robot) seems inevitable now. And how about the birds? Much will de- pend on the pace of climate change, which will determine so many things—the shapes of landmasses, including islands, the sever- ity and frequency of storms, the availability, indeed existence of habitat and food. To speculate about birdlife in 2036 seems to in - vite despondency. Let's assume that the Paris Agreement and other efforts manage to pre- vent catastrophe but that the trends we have observed over the past several decades will continue. What might we expect? Like ibises, Pelecaniforms seem embold- ened to wander during the warming period, not just pelicans (now found just about anywhere, it seems) but cormorants, trop - icbirds, and boobies as well. Irruptions of boobies during cycles of prey scarcity are not new, and perhaps the recent inland dispersal of adult Atlantic Brown Boobies in the East is driven by such desperation. Could these birds, like pelicans before them, be part of a wave of range-expanders, seeking and sometimes finding new northerly outposts for nesting? This does not seem likely, given the species' ecology. But could Brown Boo- by nest north to North Carolina some day? New northerly records of Masked Booby (New York; Massachusetts), and Red-footed Booby (Nova Scotia; Alaska) perhaps should have prepared us for the more-recent arrival

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