If first winter birds have their feathers dyed black, creating an artificially large bib, they rise in the dominance hierarchy past females and other young males. It is usually found in flocks up to several dozen in winter, individuals regularly wandering outside of the "normal" range and turning up in flocks of other sparrow species. Reproduction Breeding pairs establish a territory of about . Nests are usually constructed in early to mid-June. Eggs are usually laid by late June to July, depending on when snow in their habitat completely melts. In this species, nests are placed in a well-hidden spot on the ground underneath a thick bush or small conifer or in mossy depression in thick grass clumps. Both parents build a cup nest out of twigs, grass, moss and lichens and line it with fine grasses. From three to five eggs are laid, being variably greenish or greyish in colour with differing degrees of small reddish-brown spot. Eggs average in size and weigh approximately . The incubation stage lasts for approximately 13.5 days. The chicks weigh about upon hatching. The young will fledge in about 8 to 10 days, from July 4 to July 13. About 3 weeks after fledging, the young become independent of their parents. Second clutches may be laid if the first is destroyed, usually prolonging the brooding period a further three days for the parent sparrows. The species is arguably the least studied North American sparrow due to its isolated nesting territory. The first nest ever found was discovered 1931 in Churchill, Manitoba by ornithologist George M. Sutton, 91 years after the species was initially described. Longevity and mortality The Harris's sparrow has lived for up to 11 years and 8 months in the wild. Predators on the nest can including varied terrestrial mammals, including Arctic ground squirrels (Spermophilus parryii) and stoats (Mustela erminea). Harris's sparrows provide an easy target for these predators due to the location of their nests on the ground. Canada jays (Perisoreus canadensis), northern shrikes (Lanius excubitor) and merlins (Falco columbarius) can be a serious predators at the nest (including both nestlings and adults). Shrikes, sharp-shinned hawks (Accipiter striatus) and great horned owls (Bubo virginianus) are known predators of wintering Harris's sparrows. As an anti-predator adaptation, Harris's sparrows fly up into trees when startled by other animals, usually issuing an alarm call in the process (weenk). They duck down to the