Lancaster County, Pennsylvania has four handsome, resident owls- great horned screech, barred and barn. Those kinds of owls live here the year around: They don't migrate. But Lancaster County also is host to four other attractive species of owls during the winter only- long eared, saw-whet, short-eared and snowy. The first two species roost each winter day in rows and patches of coniferous trees in older suburban areas and hunt mice in nearby fields at night. The latter two kinds of owls roost by day in fields and hunt mice in those same fields, mostly at night. All these owls nest farther north and come to this area, and through much of the United States, for the winter only. They migrate south where mice and other prey is more accessible because of milder winters.
All these species blend into their surroundings, which keeps them from being heckled by crows, jays and other types of birds during the day when the owls need to get rest between hunting forays at night. Like all owls, they have soft wing feathers that allow them to have silent flight. Silent flight allows them to swoop down on their victims undetected, increasing their chances of catching prey. And like all owls, these owls swallow their prey whole. Their stomachs digest the soft parts, but wrap the fur and feathers around the bones, creating pellets that are regurgitated through their beaks when the owls are on their daytime roosts.
Long-ears have tall feather tufts on their heads, which gives them their name. Those tufts help with camouflage in the trees and make the long-ears look bigger than they are. A medium-sized owl, they are a foot and a half tall.
Long-eared owls spend winter days hidden away in taller conifers and hunt mice at night. Sometimes, several of them perch together in taller conifers. Over the years, I have seen a few groups of them roosting quietly and solemnly in groves of evergreens. Most gatherings stayed motionless in the trees, relying on camouflage for safety.
Long-eared owls raise young in stick nurseries made by crows, hawks or herons in tall, protective coniferous trees. They nest across Canada, the western United States, the northern part of the Middle Atlantic States, New England and in Eurasia.
Northern saw-whet owls are the smallest owls in eastern North America, being only seven inches long. They nest in cavities created by yellow-shafted flickers, which is a kind of woodpecker and pileated woodpeckers in deciduous trees in mixed deciduous/coniferous forests in northern North America and the Rocky Mountains. They also hatch young in nest boxes erected especially for them. Male saw-whets start their breeding cycle around the end of January when they call "too,too, too, too in seemingly endless series of notes. That calling proceeds every night into early May.
Saw-whets winter through much of the United States, including in older suburbs. They perch by day in protective evergreen trees, particularly arborvitae, also known as northern white cedars.
Saw-whets mostly consume deer mice and field mice the year around. And certain, larger hawks and owls prey on the diminutive saw-whets.
Short-eared owls have short feather tufts that are hard to see on their heads. This type of owl lives and rears offspring in open habitats, including marshes, prairies, tall-grass fields and so on across Canada and Alaska, and in the northwestern United States. They winter in the United States. And populations of them live and breed in Eurasia and Argentina.
Short-ears often hunt mice before dusk and can be spotted, along with their hawk counterpart, the northern harrier, fluttering buoyantly and moth-like low over open habitats in search of mice. When victims are spotted, short-ears abruptly drop into the vegetation to seize them in their sharp talons.
The stately snowy owls only get to Lancaster County one winter in every four or five, as a result of lemming population crashes on the high tundra where this owl species nests. And then we usually only see one or two snowies here in a winter, which still thrills birders and non-birders alike. But during the winter of 2013-2014, we saw several snowy owls hunched on Lancaster County's largest fields that must have reminded those regal birds of the tundra where they hatched. Here they caught and ate mice, birds and other creatures they could subdue. I saw one snowy on top of a dead snow goose it was ingesting. I don't know if the owl killed the goose itself, (it certainly could have), or was scavenging that large waterfowl.
The most interesting thing about snowy owls is their reproductive cycle. When lots of lemmings, which is a kind of rodent, overrun the tundra, male snowies are well fed and offer their mates gifts of lemmings to eat. That giving seals the bond between male and female to form a pair and builds up her energy reserves, resulting in her laying several eggs in a clutch because there are plenty of lemmings to feed lots of owlets. But if lemmings are scarce, the male eats every critter he catches, gives his mate no gifts and she lays no eggs that year. It is a built in birth control. But as the lemming populations build up so does that of snowy owls. And when the lemming population crashes, many snowy owls, particularly the young of the year, drift south for the winter in hopes of finding abundant food.
This winter, or succeeding ones, watch for these migrant owls. They certainly make a winter more exciting.
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