After the death of her mother, Margaret Renkl tenderly placed in an antique jar the "soft white hair" left behind in her mother's hairbrush. Years passed. When it no longer carried the scent she cherished, Renkl laid the hair across a holly branch in her yard.

This act was meant as a direct invitation to the birds in her yard, and it was accepted: A chickadee flew off with the hair for the nest she was building.

Renkl devotes only a half-page to this story, but it conveys the beautiful tangle of human and other-animal lives at the heart of The Comfort of Crows: A Backyard Year. Starting in winter and continuing through the seasonal round, Renkl brings alive in 52 chapters her love for the animals and plants in her half-acre yard in Tennessee and in nearby parks. Equally moving, she confesses her despair at the human-caused crises the natural world faces, and her determination not to sit idle. "The very least I owe my wild neighbors is a willingness to witness their struggle, to compensate for their losses in every way I can, and to speak on their behalf about all the ways I can't," she writes.

Renkl makes good on that pledge. She medicates a neighborhood fox against mange, with the help of a trap, a bit of bacon, and advice from a veterinarian; ensures that leaves from the trees in her yard are left unraked so that insects overwinter and ground-foraging birds can dine there; fills a garden with milkweed in support of monarch butterflies; and creates a haven for tree frogs in the form of a 40-gallon tank filled with water and frog-friendly plants.

She even keeps a worm composter at the end of her writing table, filled with coffee grounds, banana peels, vegetable parings, and "several thousand red wigglers." I can picture Renkl at work writing her weekly New York Times column right there next to these industrious invertebrates, whose own labor fertilizes her outdoor pollinator garden.

With these steps, Renkl refuses to give up in the face of human-caused global warming that is altering our environment and harming other species. Just as many of us do, Renkl sees this harm primarily through absences. For two decades, Renkl hasn't seen a turtle or toad in her yard, and only one grasshopper has appeared in each of the last two years. Fewer birds come as well.

Renkl laments that our species has been "burning this world down" since the time of "the very first hominid to rise up on bare feet." From the perspective of anthropology, I think this statement misses the point. Around 4 million years ago, the period in which our ancestors began habitually to walk bipedally, no one was burning anything down either literally or metaphorically.

Our ancestors at that time, living in small groups, gathered foods from the land and much later began to hunt. Only very late in the ongoing course of human evolution did Homo sapiens veer into industrial levels of harm that wreck the climate in completely unprecedented ways.

Compared to the tone of her earlier collections of essays, Late Migrations and Graceland, there's an extra wistfulness in Renkl's writing now. That's not solely owing to what's happening to the natural world. Renkl's parents have died and her three sons have all left home, "packed off to their own lives"; Renkl is "a little bit lost and a little bit ragged."

She's in her 60s now, "an old woman" who has entered the "last third" of her life "if what we mean by last third is whatever happens after everything you were working toward has already happened." Endings, though, are also beginnings: "This is what I tell myself again and again."

An older woman's freely sharing a yearning for her adult children is as welcome as it is poignant. So too is Renkl's resistance to our society's preference for a positive attitude no matter what. Yet I do want to ask Renkl, why label an age in the 60s (an age I share with her) as old? Healthy living at 60-something is a privilege many people around the world do not get to have. Might it be better framed as a fresh opportunity to help the ailing world in exactly the ways Renkl pledges?

In these days of climate crisis, the phenomenon of ecological grief is real. In order to seize opportunities to help, many of us do require fuel to restore our spirits. Find that fuel in Renkl's chapters like "The Bobcat Next Door," "Praise Song for the First Red Leaf of the Black Gum Tree," and "Loving the Unloved Animals."

Find it as well in illustrator Billy Renkl's lovely drawings including those of a winter garden, a pileated woodpecker gazing at a housing development and, of course, crows.

The animals and plants so cherished by Renkl need us now more than ever.

Barbara J. King is a biological anthropologist emerita at William & Mary. Animals' Best Friends: Putting Compassion to Work for Animals in Captivity is her seventh book. Find her on Twitter @bjkingape.