Climate change is changing the migration routes of animals worldwide. Take the mule deer for example. Every spring in Wyoming, green-up first appears at lower altitudes before progressing up the mountainside. Migrating mule deer follow and seek food on this green wave. But as a changing climate leads to more frequent and more severe droughts, the greenery is not as abundant as it used to be.

Ellen Aikens, a researcher from the University of Wyoming, tracked mule deer as they surfed the green wave. In comparison to wet years, the green-up lasted across the landscape for about half as long in drought years and was also fragmented. Although the deer were able to keep up with the faster green wave, the nutritional value was lower, leaving the animals less prepared for the challenges of the year ahead.

Meanwhile in Europe, the population of Bewick’s swans that spend the winter in the Netherlands is declining. But when researchers looked at the data more closely, they found an increase in the wintering population of swans in Germany. It turns out that since the 1970s, the swans’ wintering habitat has shifted an average of 13 kilometers to the east each year.

“The swans like to spend time where it’s 5℃. And the temperature line has shifted in the same rate as the swans shifted eastward,” said Rascha Nuijten, an ecologist at the Netherlands Institute of Ecology.

These findings are important to our understanding of the conservation of migrant animals. When it comes to protecting a certain species, it’s not just about the current situation. Nature is dynamic. And the species that is present now might not be present in 10 years, not because we didn’t protect it but because maybe it is dynamic in its way. We need to include the dynamics of nature into our legislation and management.

In 2009, I rescued a skittish donkey. Bo came from a nearby cattle ranch and now lives peacefully on my ranch in the Bitterroot Valley of Montana. But the key to Bo's successful recovery from nervous rescue to happy ranch animal wasn't anything I did. It was my grandson, Dylan.

Dylan came with his parents to spend some days with me on their way to Canada for a vacation. Bo kept his distance from the grown-ups, but he showed an unusual fascination with Dylan. So we decided to introduce them.

“Move slowly, be quiet, and stoop down sometimes,” I told my grandson. Dylan carefully approached Bo, step by step, holding a soft rubber currycomb. Bo held his ground, but he seemed interested by this little visitor. Dylan rubbed Bo's shoulders and neck with the comb, softly and gently.

It's hard for an almost four-year-old to stay still for long. Dylan made one quick move, and Bo was terrified running off. But Bo and Dylan were not ready to give up. Dylan approached again. It was amazing to witness a preschooler learn to control himself in such a short time.

As we watched, true love developed between this once distrustful donkey and a gentle boy. Over the next few days, Dylan felt free to sit at Bo's feet while Bo carefully nibbled his shirt collar and hair and rubbed Dylan's back with his bristly chin. Just as Dylan had earned Bo's trust, Bo came up to and hugged him --- yes, a donkey can hug — without knocking him off balance.

They met again one week later as the family passed through on their return trip. It was almost dark, but Dylan and his dad travelled far to reach the ranch. Bo came to meet them cheerfully. He is now a changed and trusting donkey.