REDDING, Calif. – Something just didn’t look right.

Terri Lhuillier, an avid eagle-watcher in Redding, California, had been keeping an eye on this particular nest outside of town since May. But by this day in mid-June, when she and her husband were going over their most recent batch of pictures, they noticed something in one shot that they hadn’t picked up on.

When they went back to get a better look, they realized why the little speck had been so easy to miss.

“I couldn’t believe my eyes,” Lhuillier said. “I was looking, and I was like, ‘Wait a minute, that body is way too much smaller than the other two.’”

A red-tailed hawk chick was in the nest with two adoptive eagle siblings, coexisting with two eagle parents that would normally turn it into dinner.

“I mean, every time I see it, I’m like, ‘How is this little thing surviving amongst four bald eagles?” Lhuillier said. "(Eagles) have some of the best vision in the animal world. You’ve gotta know something doesn't look right here. I mean, this doesn't look at all like an eaglet, and they’re not reacting to that at all. So we’re just like, 'Yes, love is blind.'"

It’s a phenomenon so undocumented that renowned wildlife biologist and eagle expert David Hancock dropped everything to come to California from British Columbia once Lhuillier tipped him off to the unlikely new family unit.

“It just was a necessary participation,” said Hancock, who also started the Hancock Wildlife Foundation. “Unless you’re human, you don’t go and raise your dinner. … It’s so seldom been observed.”

In his long career observing eagles, Hancock has known of only a couple of similar incidents. One of them, a baby hawk nicknamed “Spunky” that lived near Hancock in Canada, made international news in 2017.

Lhuillier and her eagle friends have nicknamed this hawk "Tuffy" in tribute to Spunky and the toughness it takes to have survived this long in the nest of a predator. Lhuillier said it seems to have struck a balance between self-advocacy and self-preservation by staying out of the way of its siblings but jumping in for food when the right moment presents itself.

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"It has to be a very feisty little thing to survive in the world of these four much larger birds that could take him out quickly," Lhuillier said. "And there you go – it's surviving."

In this case, Hancock believes one of the eagle parents probably snatched the hawk baby from its own nest to eat, but then the hawklet's cries – very similar to those of eagle chicks – activated some kind of parental instinct to nurture the creature instead.

Because small animals often don’t survive the airborne voyage in an eagle’s sharp talons, that could explain why – once it got to the nest alive – hearing the hawklet’s pleas altered the eagle’s plans.

“And from that moment on, it’s a member of the family," Hancock said, "not an edible component."

A less likely scenario? The hawk’s mother just accidentally laid one of her eggs in the wrong nest.

Whatever circumstances brought him or her to the eagle nest, by now, the little hawk sometimes even gets fed by its new parents first. The Record Searchlight has agreed not to list the location of the nest because eagle advocates don't want the family to be disturbed by crowds.

Since the hawklet has been watching its adoptive parents mostly catch fish – not a regular part of the hawk diet – it'll have to learn to listen to its inborn nature once it's grown. After a failed attempt at fishing or two, Hancock said, the hawk probably will listen to its instincts and go for birds or small ground animals instead.

So when could that happen?

Hancock predicts the little hawk will fly for the first time in under a week, though it could be earlier – and by accident – if the chick flaps his or her wings when the wind is just right. The little bird's eagle siblings, on the other hand, have a while before they'll be out exploring.

Hancock said hawks typically come back to their nests for a little bit as they’re coming into their own, but then they part ways with their families.

Because he doesn’t want to disrupt the birds by trying to monitor them once they leave the nest, Hancock said, it’ll be a mystery what ultimately happens to the hawk.

But for Hancock, watching and wondering what's behind this rare behavioral shift has been enough.

“How does a bird go from acknowledging that this is dinner, catching it and it’s dinner, and making that switch to ‘Oh my goodness, I’m going to now nurture this instead of eat it'? From the biological point of view, that’s a huge, huge, huge jump,” Hancock said. “Science and so on is based on observation. You see it happen, you accept it, and figure out the how and why. That’s really why we’re here. You don’t expect it, but it has happened.”

Follow Alayna Shulman on Twitter: @ashulman_RS.