In 2012 a hippo fell into a game-lodge swimming pool in Limpopo, South Africa. He was young, just four years old, and had been chased from his herd by a dominant male. The pool was without steps, and it was oddly impossible for the hippo to get out. He was soon named Solly by the lodge caretakers. News of Solly’s plight spread quickly around South Africa and beyond. It was the ideal clip for the end of the evening news, a cheerful reminder of life’s small absurdities — how a hippo can end up stuck in a pool!

And it was ideal in another way, too: because we could solve this. We were looking forward to solving it. By and large humans are the absentminded tormentors of animals everywhere, but occasionally we adopt a more benevolent role, and we really like ourselves for it: caretakers, like God asked, maybe even saviors. On talk radio we all called in with our suggestions: How about stacking sandbags so he could walk out? What about tractor tires as steps? Or installing a ramp? Solly fell in on a Tuesday, and three days later, before he could be sedated for a final rescue effort, he died of a suspected heart attack. His corpse was hoisted out with a crane.

“He was not as perky this morning, more agitated, like he was irritated,” the lodge manager told the press afterward; “I think because he wanted to get out of the pool. That’s my personal opinion.”

It was a humbling sort of tragedy. A reminder of how little we know about hippos, and much else besides. An unsubtle reminder of how inept and bewildered we really are in this world; of how little we can fathom, let alone fix.

When a hippo falls into your pool, there are a lot of people you can call: rangers and researchers and veterinarians. There are contractors and bystanders and guys with pickups and lots of ideas. But the smaller the animal is, the fewer people there are to involve. If I came across a dog or a deer or an albatross in mortal distress, I would probably seek out some higher authority, but it would be a bit absurd to call a park ranger on behalf of a mole, or to take every pigeon with a mauled foot, or every cat-bitten mouse, to a vet. These injured creatures reside in an unregulated no-man’s-land, where we have designated whoever finds them as the final and appropriate arbiter on questions of life and death.

In a sense it is precisely on account of the triviality of these crises, from a broader social perspective, that they can come to have such an outsized significance on a personal level. When you are deciding the fate of one of these countless, unspectacular small animals, there is no oversight and no authority. There’s no established norm for you to follow, nor to break. And there’ll be no one to condemn you if you fail, nor praise you if you succeed.

In such moments questions about the nature of death — which we usually consider abstractly, if at all — become not only concrete but urgent. When does a life cease to be worth living? How much suffering is too much? What constitutes a “good death”?

A few times a year, especially in spring, one of my cats clambers through the flap in the door carrying some fresh dilemma for me. Sometimes I decide the prey is beyond saving, and I need to kill it myself. When you work with death, instead of against it, you find that it has a gentler side. Death offers a promise that this pain will soon be over.

Even so, it is not easy to be the executioner. No matter how much you think you should, you’ll find it’s hard to snap a neck or stomp on a head or slit a throat. It might even be impossible. So it was that I once found myself trying to gas an injured bird beneath a pot on a stove top. I intended only for it to expire peacefully. I was trying to give it the sort of death I would want. The bird, however, would not succumb, and I heard its enduring flapping beneath the metal. I tried over and over before finally learning that domestic gas hasn’t contained carbon monoxide for decades now.

If the decision to kill initiates one dilemma, the decision to save initiates another. My reign as a god of small things, from childhood to the present, has been a long and difficult lesson in just how inadequate good intentions are when it comes to broken legs, injured wings, bitten abdomens, and fallen fledglings. When shock alone is the problem, my treatment regimen is highly effective: I put a weak, limp creature in a box, and I open the box some hours later to find something bright and vital that can be released back into the world. On those days I stand, sun warming my cheeks, and bask a little while in my gentle humanity.

But when anything more serious is amiss, my success rate is lower than a medieval physician’s. Most recently I found a pigeon with a broken leg dragging itself around on my street. It was, as ever, with no clear plan that I brought the bird over the threshold of my flat. It was unable to lift its head on its own, but when I held its beak to water, it drank. When I offered it seeds, it ate. I thought I could see it appraising me, first with one eye and then with the other — considering my intentions and therefore its fate.

Online you will find discussion groups and videos dedicated to whichever small-animal crisis you happen to be presented with. It’s a well-meaning if hectoring community, full of strong opinions on what animals should and shouldn’t eat. What do you feed a starling? A tortoise? A shrew? It’s never what you think. But these forums can also be places of real solidarity and kindness, a great army of people who hope, once in a while, to do a small, sure, and good thing. I once successfully followed a list of instructions for how to revive an exhausted bee, including presenting it with a Q-tip soaked in sugar water. The list ended with the reflection that it is “very satisfying to rescue a creature.”

There was plenty of advice on birds with broken legs. They heal remarkably fast, a kindly man explained in a video. All you need to do is keep the bird fed, comfortable, and off the leg for a week or so. To achieve this, you needed to fashion a little harness. The day, for which there had once been other plans, was soon lost to a series of amateur engineering projects. I needed an enclosure that could support a harness, a harness that could hold a bird, and a fabric both elastic enough to allow comfort and firm enough to guarantee restraint.

The birds in the videos all looked peaceful and content, dipping their beaks into small bowls of food whenever they felt peckish. My bird, by contrast, was in a state of endless misery, protest, and despair. Every time I returned the cage to cleanliness, it would revert to chaos. I was too afraid to bind the bird tightly enough to keep it from struggling free. I kept fussing over it, rewrapping this and restringing that. As night fell, I faced the awful decision of whether to leave the bird in its ill-fashioned harness, which was clearly causing it enormous distress, or else untie it, in which case it would be unable to eat or drink.

I left it bound and slept badly. In the morning I found that the bird, who the day before had looked at me with a certain wary hope, had since realized its terrible mistake. There would be no explaining to it that I was merely incompetent, not cruel; no escaping my villainy. I cut it free from the harness even as it lashed out at my approaching hand. It dragged itself on its wings with a tragic determination to get away from me. The room was now covered in bird shit and seed and spilled water and soiled washcloths and damp newspaper and the sour smell I’ve come to recognize — from too many years and too many birds — portends death.

I had charged home the day before intent on rescue and managed instead to do little more than torture an injured animal for twenty hours. I wept to have failed so spectacularly, and perhaps, too, because it resembled all the other occasions when I thought I could solve this, when I was looking forward to solving it, and when I couldn’t instead. When even your best effort, and the best of your nature, is insufficient, it might be worse than nothing at all.

I said earlier that, when it comes to small creatures, there is no recourse to a greater authority, but that is not always true. Where I live, in Cape Town, there is World of Birds, a wildlife sanctuary that is willing to politely accept through a hatch at its gate whatever sorry avian offering you bring them. The proprietors ask only for a donation, which you gratefully make, relieved to be back in the familiar world where money ostensibly solves problems. You leave unburdened, and presumably they carry out, when necessary, the euthanasia that was somehow beyond you.

I once brought them a wounded hadada-ibis chick, because I didn’t feel equipped to rule on its life or death. When I arrived, they told me that my charge was in fact a fledgling pigeon. I felt almost deceived by the bird, as if it could have imagined how tenuous its significance was to me; that if it were another genus, I might not have bothered with the journey.

These small animals take on all manner of roles within our lives. One rat might end up a cherished pet, its belly stroked as it lies within a palm. Another might become a “hero rat” who sniffs out land mines in Angola or tuberculosis in Tanzania. A third might even be sent into outer space for experiments in “microgravity.” Many more will die in research labs or have their necks snapped in traps within our homes. They are put in these various roles based on our whims alone. By our very caring, one rat becomes worthy of cherishing while all the others are granted no worth at all. As long as this is so, we keep ourselves safe within our contradictions.

I had two pet rats as a child. They were white with glassy pink eyes. (The pet shop also sold “pinkies” as snake food.) After a few years my rats became hopelessly ill and enfeebled. My father — perceiving with some dismay that the task fell to him — took the rats out to the garden to kill them. He had in mind a brief, firm strike to the head with a spade or rock. This was his inner negotiation, and his idea of a good death. After a little while he came back into the house and declared it done. We laid some flowers over the grave.

Years later my father confessed that, when it had come down to it, he’d been unable to strike the rats. Instead he’d buried them alive, watching in horror as their weak claws struggled against the soil he heaped on top of them. In his cowardice he’d given them a far more awful death than the one he’d planned, and his failure haunted him.

It haunts me, too, even though we’ve killed other rats, and so many more have died on our behalf. All the pills you take and vaccines you get and treatments you undergo and creams you apply have, in their secret history, the miserable lives and premature deaths of millions of rats and mice. In Siberia there is a bronze statue of a laboratory mouse knitting the DNA double helix, commemorating what mice have endured in the name of scientific research.

Once, when I was young, our house had a particularly unwelcome rat who was taking toothy bites out of all the fruit in our kitchen at night — and was even so brazen as to sink his teeth into my earlobe as I slept. We caught sight of him now and then on his furtive escapades and called him, unimaginatively, “the rat.” As it turned out, the name was deeply imaginative: we’d imagined this was a single rat when in fact it was about thirty or forty of them, as we discovered when we finally undertook the awful task of extermination. We chose poison, and it was the wrong choice. Its cruelty was soon made apparent. The rats, reduced to an agonized crawl, were now everywhere to be found. Too weak even for fear, they died in horrible slow motion all around us.

There was another infestation in my block recently, this time of mice. Everyone heard them scampering behind the drywall and roaming through the attic spaces. An e-mail chain started among the trustees about bringing in “rodent control.” Price quotes and methods were compared.

Meanwhile one of these mice was loose in my flat. My cats were ricocheting around the furniture in constant pursuit. They crawled behind the bookshelves and sent half of the classics crashing to the floor. They clambered beneath the kitchen counters in predatory delirium. This was no ordinary mouse, though. This mouse was Jason Bourne, and it evaded them at every turn. Finally it found a place beneath the piano where it was truly unreachable. The cats’ constant vigil lasted for days, each relieving the other from duty, knowing their prey would eventually have to relent and venture out.

At some point, however, this mouse had become a cherished mouse. I’d begun to root for it. I prepared tiny meals — bottle caps filled with water and hunks of bread and cheese — and pushed them beneath the piano on a sheet of cardboard. When I found that my offerings had been accepted, I shone with a quiet satisfaction. It was an unlikely collaboration, sure, fundamentally compromised on almost all fronts. (The trustees had by now booked the “rodent inspection.”) But for a little while the mouse and I were in it together.

Beyond those four walls, the world was both cruel and beautiful: civilizations rose and fell; the great sky flashed; the deep sea yearned. But within them, a mouse had made it through another day.