In tallying up the casualties of war, there’s seldom a thought for the animal kingdom beyond our own two-legged species. It’s assumed that Mother Nature will simply “adapt,” her less-evolved populations abandoning old habitats and finding new ones on their own when forced. “Checkpoint Zoo” trains its lens on 5,000 or so beasts who didn’t have that option — Russia’s invasion of Ukraine left them trapped in cages or pens on a no man’s land between enemy forces, terrorized and sometimes killed by missile strikes.

Joshua Zeman’s documentary chronicles the courageous efforts to save them, first from starvation, then via transport to new homes. There’s no lack of suspense, human interest or unique animal footage in this engrossing feature, whose broad appeal should ensure wide exposure — at least among allied nations.

Wealthy businessman Oleksandr Feldman founded Feldman Ecopark outside his native Kharkiv to share a...