Swifts and Swallows are often mistakenly considered to be closely related. Although they share similar habits, they are representatives of two distinct families. Swifts share a family with the swiftlets, while swallows are grouped with the martins.
Certain species of swiftlet use echolocation to navigate within the total darkness of caves. They do this by emitting a series of clicks and examining the returning echoes to determine the position of solid objects. This is most prolific when birds are approaching their nests. The process is much more simple than that used by bats.
What’s the Difference Between Swifts and Swallows?
Swifts and swiftlets are actually more closely related to the hummingbirds, although the two appear quite different. Both the swifts and the swallows have long pointed wings, short, weak legs and wide beaks, designed for catching insects. They both follow a largely aerial existence, and it is this lifestyle that has led to their similarities. A process termed convergent evolution, explains that species that inhabit specific environments, develop certain adaptations. These adaptations may independently arise in two quite distinct species, provided that the environments that they inhabit and their general habits are similar. Thus, in swifts and swallows, the two are acrobatic, fliers, that feed on insects and other invertebrates, caught within the air. Although, the two are separated by certain internal structures and feather configurations, swifts have longer, more slender wings and seldom land.
Do Swifts Ever Land?
There are approximately 85 species of swifts and swiftlets found throughout the world. Both swifts and swiftlets have wide mouths, designed for scooping up insect prey, and their sleek bodies, with long tapered wings, are highly manoeuvrable and well-suited to their aerial existence. Swiftlets are smaller and more slight than the swifts. Four or five (depending on how they are classified) species of swiftlet have been recorded in Australia’s far north, but the Australian Swiftlet, Aerodramus terroereginae, is the only breeding resident. The House Swift, Apus affinis, has been recorded in Australia only as a rare vagrant, but the two, more common, swifts seen in Australian skies are the Fork-tailed Swift, Apus pacificus, and the White-throated Needletail,Hirundapus caudacutus, altough only as non-breeding migrants. These two species were, for many years, not thought to land at all during their time in Australia. All activities, such as sleeping, thought to be carried out in the air. This misconception was firmly held until the mid 1970’s, when several roost sites were discovered. More recently, radio-tracking has confirmed that the birds roost in tree hollows, normally returning to the same site each night. In swifts all of their toes are faced forwards, and their short, sharp claws are well-suited to clinging to vertical surfaces. Both the Fork-tailed Swift and the White-throated Needletail, arrive in Australia in October each year, and depart for their Asian breeding grounds in about April or May. Some birds may be seen as late as August, if conditions are favourable.
While the White-throated Needletails are not the fastest flyers in the avian world, a myth that is often attributed to the species, they are able to achieve great speeds of up to 130 kilometres per hour. It is generally conceived that larger birds are capable of faster flight speeds than smaller birds, particularly when cruising. The fastest recorded flying speed is attributed to the Peregrine Falcon, which, in a dive, may reach speeds in excess of 180 kilometres per hour.
What is in Birds’ Nest Soup?
Swifts and swiftlets, develop large salivary glands when breeding. The swiftlets use this saliva, in conjunction with other materials such as cobwebs, moss and other plant material, to construct their nests. The swiftlet creates a semi-circle of saliva on the proposed nest surface, which dries quickly and forms the foundation of the nest. The Edible-nest Swiftlet, of south-east Asia, constructs a nest entirely of saliva. The quick-drying saliva is applied in layers, until the cup shaped nest is complete. These nests are highly-prized, being harvested for the famed birds nest soup’, a delicacy in Chinese cuisene. Surprisingly, considered as a delicacy in many areas. The nests are harvested at the completion of the breeding season, with numbers exceeding 300,000 from a single cave in Rongkop (central Java). The nests are prized as an aphrodisiac, and may be served as a jelly, either spicy or sweet, as well as in soup.