The Remarkable Hummingbird
The most peculiar and impressive of all bird species is quite possibly, the hummingbird. Over 300 species of hummingbird are spread throughout the rainforests of North and South America, ranging in colours, shapes and sizes. What all these hummingbirds have in common is speed – they are the fastest species of bird in relation to their size.
Hummingbirds generally fly at an average speed of about 50 kilometres per hour, flapping their wings approximately 80 times per second. When diving, however, their speed can surpass a fantastic 95 kilometres per hour. Speeds vary for different species, usually depending on size and shape, the fastest being Anna’s hummingbird, which dives at a rate of 385 body lengths per second. They can fly in all directions including backwards and upside down and hover by flapping their wings in a figure-eight movement.
When trying to attract a mate, male hummingbirds perform a ‘dance’, flying in a U-shape, and when doing so, their wings emit a humming sound similar to the songs of other birds, earning them their name.
Hummingbirds don’t just move fast, though; they live fast – their hearts beat can reach an average of 1,260 beats per minute! Living for an average span of four years, their gestation period is a mere 13-22 days, after which the young begin to fly in only 18-30 days. Even when eating their usual diet of flower nectar, tree sap, pollen and sometimes insects, they use their extremely long tongues to lick their food at a rate of 13 licks per second – there is really nothing these birds do slowly. Due to their fast lifestyle, their body temperature usually sits at about 40 degrees Celsius. Due to their high body temperature and heart rate they have a large metabolism, requiring roughly double, or sometimes triple, their own body weight in food each day.
In order to survive cold nights, hummingbirds regulate their metabolism and body temperature in a similar way to hibernation, except only on a nightly basis at any time of the year – this is referred to as ‘noctivation’ and basically means that the bird lowers its metabolic rate by 95% and cools its body thermostat, allowing it to use 50 times less energy and go the night without food. This is especially useful for hummingbirds during migration, as many species spend summer in North America and then migrate to the tropics for winter. Some species migrate much further than others, travelling up to 4,800 kilometres.
Of all 300 or so hummingbird species, the smallest is the bee hummingbird, found only in Cuba and the Isle of Pines. The bee hummingbird is the smallest bird in the world and it is truly tiny – its length from beak to tail is only five to six centimetres, with a total body weight of between 1.6 and 1.9 grammes! It gets its name due to its similarity in size to a bumblebee. In comparison, the largest hummingbird is the giant hummingbird, found in two subspecies across South America, which doesn’t really live up to its name, only reaching 20 centimetres and 20 grammes – about half the length of a magpie and only about a tenth of its weight. While the bee hummingbird is stunning in its colourful plumage, with blueish-green backs and glossy pink heads on the males of the species, the giant hummingbirds have very dull plumage, all greys and browns, but are unique in shape, with exceptionally long beaks and tails.
The most common hummingbird is found across most of North America, being the ruby-throated hummingbird. Sporting emerald-green plumage and, for the males, red throats, earning their name, ruby-throated hummingbirds are average in hummingbird size with a length of about nine centimetres and weight of about three grammes. Like many other hummingbird species, they spend summer in North America and migrate south, usually to Mexico, Central America and Caribbean Islands, to spend the winter in tropical climates. During migration, the ruby-throated hummingbirds, and a few other North American species, cross the Gulf of Mexico without stopping, taking 18-20 hours. Many species of hummingbird are endangered, such as the mangrove, chestnut-bellied, Oaxaca and scissor-tailed hummingbirds.
Many years ago hummingbirds’ biggest threat was hunters seeking their feathers, due to their unique and colourful plumage. Nowadays, the greatest threat they face is habitat loss. Mainly due to urbanisation, much of their forests and woodlands are being cut down and they are losing access to food and nesting areas. Another threat that the hummingbird faces is climate change, as changing temperatures can affect their migratory patterns, making food harder to find – especially difficult for an animal that needs to eat so often.
The most endangered species, the only one listed as Critical on the IUCN Red List, is the sapphire-bellied hummingbird – a stunning medium-sized hummingbird with a glittering blue underside and shining green back. The sapphire-bellied hummingbird is native to Colombia, with an estimate of only 70-400 individuals remaining, with a decreasing trend. In North America, where hummingbirds frequent in summer, locals are planting specific flowers in their gardens to attract hummingbirds and give them an alternate food source.