Peregrines, the Ultimate Birds of the Air

Last week I wrote about hawks and never once mentioned the peregrine falcon. This falcon, along with the Merlin (another falcon), the golden eagle, and the goshawk, were all observed migrating past the hawk watch, but in very small numbers. The publicity about the peregrine has given many people the wrong impression. The falcons may be television stars, but they were never common, and still are very rare everywhere.

The stronghold of the peregrine is the far northern tundra, but even there they are few. The open air is their true habitat, which makes tall buildings a natural place to hang around. They breed, eat, and roost on skyscrapers and sheer cliffs, because they are the ultimate "birds of the air."

They capture their prey by striking them with great force during a dive from above. They use their chest as the battering ram, then circle and grab the stunned falling bird with their powerful talons. Then they pluck and devour the victim on one of their high perches.

Often readers tell me they have a peregrine falcon in their suburban back yard. You can see why one should be skeptical of such a notion. However, the much more common sharp-shinned hawks and Cooper's hawks are yard birds. They can camp out there, snatching a morsel of sparrow or dove off the ground or out of the bush and rip it apart right before your eyes.

These are the small and medium sizes of a trio of hawks called "accipiters." There is a large version in this grouping called the goshawk. It is powerful enough to capture even a goose, from which it gets its common name. Usually, its food is grouse and hares, and most goshawks dwell in northern forests where such prey is common.

Like the lemmings, northern hares have cyclic increases and crashes in population, so when they are very abundant the goshawk has good hunting and many young birds are raised successfully. When these prey items crash, this burgeoning population of young birds must move south to find food.

The scientific name for the goshawk is accipiter gentilis, a name given to the bird partly in error. The name is derived from the Latin word gens, meaning clan or tribe. In medieval times gentilis meant belonging to the higher classes of people, the nobility (gentlemen).

This was the time when many people kept hawks captive, and used them to catch small birds and game for the table. The middle class used the short winged accipiters for this purpose, including the goshawk. The long-winged peregrine was reserved for the nobility because of the spectacular way it hunted at great speeds in the open. However, the name is not completely inappropriate, because the goshawk's size and ferocity sometimes elevated it to the level of a "noble hawk."

The goshawk appears to be one of many northern species that is invading New England this winter. Another bird of prey has also arrived in unusual numbers, the northern shrike. This is a songbird related to the thrushes. It lacks the powerful talons of a hawk, and uses its bill to kill a lemming or small finch after it pins it to the ground.

A short while ago I was watching a group of bluebirds on a telephone wire. They were chattering in an odd way never heard before. Behind me there was a loud shriek, and I turned to see a shrike perched high in a sapling. This gray bird resembles a mockingbird, but without the long tail and obvious white wing patches. This was an immature whose black mask was hardly visible.

The shrike gets its name from the loud calls it can make, but it also is the author of a long and beautiful song on the nesting grounds. This bird flew right for the bluebirds, which did not move. He passed them by, continuing across the orchard to perch in another treetop on the far side. They knew the shrike was unlikely to attack them unless they were on the ground, but they did give him that scolding chatter. A sparrow feeding in your yard may not be so lucky.

Those of us who like to see raptors are fortunate when the prey of these northern birds is scarce and they come to New England.