The recent case of a Red-tailed Hawk being raised by Bald Eagles in British Columbia has captivated birdwatchers and scientists worldwide. The story has unfolded at a nest located in the small town of Sidney, in the Shoal Harbour Migratory Bird Sanctuary (SHMBS), about 30 kilometers north of Victoria. Two young hawks were spotted in the nest in late May, joining the two adult eagles and three eaglets.

The adults are experienced parents; they have been nesting in this spot for the last 26 years and typically raise two or three chicks every year.

Unfortunately, one hawk chick died and no one knows when it happened. It may have starved to death. Bald Eagles are usually hard pressed to raise their own young. It is not uncommon for them to lose chicks because they have too many mouths to feed. The first nest I ever watched started with two eaglets, but only one survived to fledge.

Two theories have emerged on how two hawk chicks came to be in the nest.

The dominant theory suggests that the eagles raided a hawk nest and brought the chicks back as food for their three eaglets. Once in the nest, the chicks begged for food, the eagles’ parental instincts kicked in, and the chicks were adopted.

“It’s not uncommon for eagles to bring back live prey, especially when the prey is small enough that the talons wrap around it,” says David Hancock, a biologist and founder of the Hancock Wildlife Foundation. He has witnessed this on three occasions with the help of his live camera feeds.

If the hawks were carried to the nest, it’s possible an eagle’s talons punctured the one that died, causing an infection or other fatal wound.

The second theory maintains that a hawk laid eggs in the eagle nest. Residents Donna and Terry Rendle saw an adult Red-tailed Hawk near the nest on more than one occasion. “It was my husband who saw the hawk perched on the edge of the nest near the beginning of May,” Donna says. SHMBS is not hawk habitat, and the hawks hunt over a kilometer away, yet I too have seen them in the sanctuary on two occasions this year.

The conundrum deepens when the incubation and fledgling periods of hawks and eagles are taken into consideration. The eagle eggs were laid in late February and hatched in early April. Around that time, the hawk eggs were laid, either in the eagle nest or a hawk nest. The hawk chicks hatched in early May.

A strong windstorm this spring knocked down many trees, so it’s possible the hawks’ nest was destroyed and they sought out another place to lay their eggs.

Did the adult hawk follow her stolen chicks back to the eagles’ nest, or was she checking up on her deposit, laid while the eagle was absent? Which theory is more plausible?

What’s noteworthy is this isn’t the first time Red-tailed Hawks have been raised by Bald Eagles. Occurrences have been documented in southern British Columbia, Washington State, and Michigan. In some of these instances, egg laying by the hawk was indicated.

The surviving young hawk, named Spunky by the Hancock Wildlife Foundation, fledged on June 23, and it’s currently doing well. It returns to the nest to be fed, and witnesses have reported seeing feedings outside the nest. Its eaglet siblings are now branching and should fledge soon. What happens when Spunky meets other wild eagles remains to be seen.

Red-tailed Hawks are about one-fourth the size of Bald Eagles, but they’re also aggressive and capable of defending themselves against the larger raptors, experts say.

When asked for his predictions on the hawk’s survival, Hancock notes that Spunky has “one thing in his favor: proof to be a survivor. Most eaglets are aggressive. This hawk has proven that audacity gets you some things.” — Sheri Rypstra

Sheri Rypstra is a writer, photographer, and artist and holds a BSc in biology. She has written for Seaside Times and other magazines. A Bullock’s Oriole photo she took will appear in the 2018 Canadian Geographic Bird Calendar. She lives in Sidney, British Columbia, with her husband and children. She thanks biologist and Sidney resident Kerry Finley for background information and research for this article.

See Sheri Rypstra’s photos on Flickr

View video updates about the hawk and eagles on YouTube

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Originally Published July 5, 2017