How come wolves howl? asks Christina Scammon, a student in Holtsville.

If you were hiking in the woods and got separated from your friends, would you yell out their names? If two of you became separated from the rest of the group, would you both yell louder and longer, feeling braver and less self-conscious? Would you find it especially satisfying if your yells echoed off rock formations, magnifying your efforts?

Of course, if you and your pals brought your cell phones - and they worked in the middle of nowhere - then you wouldn't need to yell. But wolves don't carry mobile phones (and just try to imagine punching those tiny buttons with that big paw). So howling comes in handy.

Wolves hang out in packs of about five to seven, although groups can be smaller or larger. Each pack usually lives and hunts on its own territory, which may cover from less than 20 to hundreds of square miles, depending on the pack size and the land available for roaming. Wolves bark, yip, growl and whimper, just like domesticated dogs. But although some dogs howl occasionally, wolves howl more frequently and elaborately, either alone or in chorus.

Scientists who have studied wolves - recording and analyzing howls, observing behavior, broadcasting prerecorded howls and noting reactions - say howling helps a pack stick together and fend off rivals.

Some studies show howling increases before the breeding season, when animals pair off to mate. The howling may drop off sharply when pups are born, with adult wolves keeping a lower profile to protect pups from predators. Howling increases when wolf pups are several months old.

One study in Poland found that wolves did most of their howling between 6 p.m. and midnight. They tended to howl when they were in the center of their territories rather than on the more dangerous boundaries. The researchers estimated that 43 percent of the howls were back-and-forth yells between separated pack mates.

About 22 percent of the howling was a noisy buildup to setting off on a hunt. Howls by lone wolves or pairs lasted about 34 to 40 seconds. But group howling went on for one to nearly four minutes.

Wolves seem to recognize other pack members by their individual howls even at long distance, just as we recognize the voices of friends, relatives and classmates on the phone or from across the street. Though most howling is communication within a pack, wolves also howl to publicize their presence to other packs.

Wolves howling in chorus frequently vary the pitch of their sounds. As the ever-changing mix echoes, it makes the group seem bigger, helping wolves avoid a nasty fight with another pack.
One study noted that wolves use howling as a spacing mechanism. When they are at home in an established territory, howling marks their settlement. Howling also signals packs to give each other a wide berth when migrating.

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