The skylark is a small brown bird, somewhat larger than a sparrow but smaller than a starling. It is streaky brown with a small crest, which can be raised when the bird is excited or alarmed, and a white-sided tail. Its sustained warbling song, which can last for five minutes without a pause, is usually delivered when the bird is flying high in the air, often nearly out of sight. Their singing has the twin objectives of defending territory and attracting females, and is heard from late January to early July. At other times of year, particularly in August and September they are fairly silent. After the breeding season they are often gregarious, gathering in flocks to feed and to migrate. Home bred birds are joined by winter visitors and passage birds from Europe.

The UK skylark population fell by 53% between 1970 and 2004, making it a red listed species on the Birds of Conservation Concern list. This decline was largely caused by the move from spring to winter cereals, as well as by intensified grassland management.

Skylarks nest on the ground, in vegetation that is 20–50 cm high. This vegetation must be open enough to give the bird’s easy access to the ground. They need to make two or three nesting attempts between April and August to sustain the population. Skylarks can nest successfully in late-cut hay meadows, or silage fields that are not cut before late May and subsequent cuts are at least seven weeks apart. They can nest in grazed pasture with a tussocky sward and a low stock rate through the spring and summer. Unimproved grasslands managed without inputs often hold high densities of skylarks. Their diet in spring and summer comprises mostly insects and spiders. During winter adults feed on leaves and seeds of crops and weeds.