If winter is the season when bison look the toughest, spring is when they look the sweetest.

Calving season is one of the most exciting times of the year on any bison ranch. And for a young herd like ours, every new calf is a milestone: proof that the herd is growing on its own, right here in the Bitterroot.

When bison calves are born

Bison calves are typically born in spring, often from April into early summer. Pregnancy lasts around nine months, which lines up with the summer breeding season. Timing calves for spring gives them the best start: warmer weather, fresh green grass for their mothers, and a full summer to grow before their first winter.

Why are they orange?

The first thing everyone notices about a newborn bison is the color. Bison calves are born with a bright reddish-orange coat, a cinnamon color that stands out against the green grass. Ranchers often call them "red dogs."

That color doesn't last. Over the first few months, the coat gradually darkens to brown, and the calf's shoulder hump begins to develop. By fall, they look much more like miniature versions of their mothers.

Up and moving fast

Bison calves are tough from the start. Within a short time after birth, a calf is usually up on its feet and nursing, and soon after that, it's following its mother through the pasture. Bison cows are protective, and the herd as a whole keeps the young ones close.

It's one of the reasons we give the herd plenty of space during calving season. A protective bison mother is not something you want to test.

How we handle calving season

Bison generally calve on their own, without help, and that's how we prefer it. Our approach during calving season is mostly about watching carefully and disturbing the herd as little as possible.

• Quiet observation. We check on the herd regularly, usually from a respectful distance, looking for new calves and making sure mothers and babies are doing well.

• Keeping stress low. We avoid unnecessary handling or activity near the herd while calves are young.

• Good pasture and water. Nursing mothers need good nutrition, so spring grass and clean water matter more than ever.

• Records. Over time, we keep track of new calves and their mothers so we can follow the herd's health and lineage.

A growing herd

Remember those 17 heifer calves and 4 yearling heifers in our founding herd? Bison heifers usually have their first calf at around two or three years old. That means the young females who arrived in 2023 are the mothers of the herd's future.

[CONFIRM WITH FAMILY: How many calves were born this year? Any memorable "first calf" story?]

Come see for yourself (from the road)

If you're driving through the Bitterroot in spring, keep your eyes open. Little orange calves sticking close to their mothers are one of the best sights in the valley.

And if you're following along here, we'll share photos of our newest arrivals as the season goes on.