One particular bird has abandoned its powers of flight, leaving the clouds of flying mosquitoes, midges and caddis flies for the airborne hunters, and has concentrated its feeding to the insect life on the ground. Large ground-scurrying flocks of whiffles follow the tromble herds, pecking here and there in the stunted vegetation with their long beaks. Through the weight of their passage, the trombles cause such a disturbance to the soil and moss, churning up the mud and crushing down the vegetation in deep footprints, that the insects that live there are sent scattering for new cover. The whiffles following behind are quick to snap them up. Each tromble, representing a huge mass of flesh, is prey to warble flies, fleas and all manner of other parasites which are also eaten by the whiffle flocks.
When asleep, the whiffle can draw its head into the hairy plumage of its body, and hide its sensitive beak among the narrow feathers of its chest. Like most tundra creatures, the tromble and the whiffle are found in the cold northern regions of both the Palaearctic and Nearctic realms. Several species of whiffle are found on the tundra, but they are all rather similar to one another. The body is round and the neck short, to minimize heat loss. Long slender legs enable it to wade in ponds, and the long beak, with the sensitive tip, can probe into mosses and under stones for insects.