Mountain environments, including here in the San Bernardino Mountains, are often regarded as harsh and unforgiving. It takes a certain ruggedness to survive and thrive in the mountains. But when most people think of the hummingbird, “rugged” is typically not the first adjective they would use to describe these diminutive avians.
As tiny as they are, hummingbirds are in many ways quite rugged and fierce little birds. Here in the San Bernardino Mountains, seven species of hummingbird have been recorded. By far, our most common species is Anna’s hummingbird. This bird was named to honor Anne d’Essling Masséna in the early 19th century by French naturalist René Primevère Lesson. She was the wife of amateur ornithologist François Victor Masséna, Second Duke of Rivoli. Some conjecture that Lesson was trying to curry favor with the aristocracy by naming birds for them. Given the fact that she lived in France, Ms. Masséna most likely never saw a live hummingbird.
Back to the idea of ruggedness, Anna’s hummingbird is indeed one tough little bird. It’s typically the only hummer you’ll see here in the mountains during the winter. In fact, Anna’s hummingbird lives farther north year round than any other species of hummer. They can be found as far north as British Columbia during the winter months and they breed as far north as southern Alaska. The rufous hummingbird ventures a bit further north during the breeding season, but they depart for the warmth of Mexico, southern California, and the Gulf Coast during the winter months.
Most folks know that hummingbirds feed on the nectar from a variety of flowers. Many are surprised to learn, however, that they also consume a variety of small insects and spiders. Anna’s hummingbird can often be seen perched on the tip of a branch, waiting to dart out and snatch a passing insect much like a flycatcher. Some studies have shown up to 80 percent of a hummingbird’s diet can be insects. While nectar helps provide much-needed calories, insects are a critical source of protein, amino acids, and necessary vitamins and minerals.
Hummingbirds have a notoriously fast metabolism and consume copious amounts of calories to fuel their daily activities. Such a metabolism can make life challenging in cold climates. How does Anna’s survive in cold weather? To conserve energy, all hummingbirds go into a state of torpor most nights when air temperatures drop. Torpor is essentially a type of controlled hypothermia, where the body temperature and heart rate drops dramatically. Research has shown that Anna’s hummingbird can go into a state of torpor while it’s not actively feeding, thus conserving precious calories. During torpor, the heart rate may drop from a resting rate of 500 beats per minute to about 40, and body temperature can decrease from 105 degrees Fahrenheit to around 48 degrees.
As spring migration peaks, be on the lookout for a variety of hummingbirds if you have feeders out. But when cold weather descends on the mountain late next fall, the only hummingbird remaining to brighten your day will be Anna’s.
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