Mother’s Day falls in May, but it's also when moose cows are giving birth — and experts say we should watch out.
Carl Koch is a wildlife biologist with the Alaska Department of Fish and Game. He warns that the animals can be particularly touchy when they have newly born calves.
“When they first give birth, the calf has to build muscle until it can grow strong enough to run from danger,” Koch said. “The most common thing they’ll do is bed down when they are in trouble — mom knows they can’t run away, so she’ll get very defensive.”
Koch says the cow’s most common defense is to stomp on whatever is threatening her calf. A moose can kick in any direction with its front hooves.
Koch says that cows frequently leave their calves alone for a day, knowing they will not be able to go far. Sometimes people will find a calf in this situation and assume it is orphaned.
“Interfering in that can make matters worse,” he said.
Koch remembers one occasion a few years ago in Haines, when people crowded around a calf. He says this probably prevented the mother from reuniting with her newborn.
“They may just abandon the calf — they often have twins, so they might just cut their losses if one of them is in a spot where they are having trouble getting back to it because people aren’t leaving it alone,” Koch said. “When folks call and say there is a calf in their backyard and they are worried about it, I say 'Leave it alone,' and if they have pets I say, 'Please keep the dogs out of the backyard.' Some folks want to keep checking on it every hour; we prefer they just leave it alone.”
Koch says almost every time, within a day and a half they will have moved on. About half of the moose charges Koch hears about typically occur at this time of year. He recently received a report of one person with a loose dog being charged by a cow in Gustavus.
Cows will generally give birth to their first calf two or three years after their own birth. They will get pregnant in September during the breeding and hunting season, and give birth in mid-May. That makes their pregnancy about the same length as a human mother’s, but they do it almost every year.
In an area with plentiful food, like the Chilkat Valley near Haines, Koch estimates that up to 90% of females of breeding age will give birth in any one year. With the valley’s population of roughly 350 moose, Koch guesses about 100 calves could be born this spring.
The calves will weigh the same as a mid-size dog. They will get milk from their mother but can also eat leafy plants, like willow and dogwood, just after birth. As they age, they progressively shift to an all-plant diet. Koch says around one in three calves will survive the summer.
Adult females can reach over 1,000 pounds, and live up to 17 years in the wild.
For anyone running into one of the irritable new mothers, Koch has one piece of advice.
“If a moose is charging you, do the opposite of what you do with a bear: run and get behind something big,” he said.
Koch says every year in Alaska, some people are injured by moose. He asks that any dangerous interaction with a moose be reported to the state’s Department of Fish and Game, or the Alaska Wildlife Troopers.