Here in Maine, there used to be a beloved, family-owned restaurant that served–among many other edible delights–some of the best homemade biscuits in the state. Situated on a major route leading to Down east Maine and Canada’s Atlantic Provinces, the restaurant afforded spectacular views of the Penobscot Narrows and fed both long-haul truckers and generations of vacationing families. When the restaurant closed, there were countless disappointed travelers who had built their trips around refueling themselves at that particular location.
Fortunately for humans, there are other restaurants and resources for finding them. The same can’t be said for some of our feathered friends. Because the flowers they rely on for food are blooming earlier than they have in the past, in essence, many of their restaurants have closed. A growing body of research indicates that this early blooming phenomenon is one of the effects of global warming. It raises many questions about whether or not birds will be able to survive, and what impact this will have on bird breeding, migration, and other behaviors.
Due to their aerobatic abilities and speed, their bright, beautiful colors, and their diminutive size, hummingbirds are always fun to watch. They are particularly interesting to observe in the context of early blooming, because some species of hummingbirds have already changed their migratory patterns.
All hummingbirds rely on flower nectar for 90% of their food. Unlike ducks or geese, they are solo migrators. Their migratory patterns are tied to their breeding grounds and food sources. All hummingbirds are exclusive to the Western Hemisphere, and most live in the Caribbean and South and Central America. Of more than 300 species, only 16 migrate to North America and most come only to breed. One of these, the Ruby-throated Hummingbird, migrates to breeding grounds east of the Rocky Mountains from the Gulf of Mexico to southern Canada, and is the only species that nests east of the Mississippi River.
It’s been documented that Ruby-throated Hummingbirds have changed their migratory patterns. One study compared data on the first arrival dates in North America from 2001 to 2010 with data from 1880 to 1969. Ruby-throated Hummingbird’s first arrival dates were earlier during the more recent period, and varied by latitude from approximately 11 to approximately 18 days, with less pronounced changes above 41°N (think Cleveland, Ohio).
The migratory pattern changes in the Ruby-throated Hummingbird have led bird-loving scientists and science-loving birders to examine the species more closely, and to begin to study other hummingbird species as well. Hummingbirds–and all other birds for that matter–are already at risk due to depletion of their habitat by development. Will they be able to adapt quickly enough to stay ahead of the effects of global warming? Or discover new habitats? Or keep their migratory patterns synchronized with the blooming of the flowers they need to survive?
Maybe global warming/climate change can’t be stopped, but there are ways for scientists, birders, and hummingbird aficionados to help. Do you want to be a hummingbird helper?
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