Bald eagles have been spotted nesting in the arms of a saguaro for the first time since 1937. (Photo courtesy of Kyle McCarty/Arizona Game & Fish Department)

PHOENIX – For eight decades, biologists have speculated that bald eagles build their nests in large saguaros.

This week, that speculation became reality.

The Arizona Game & Fish Department on Wednesday announced the discovery of the first bald eagle nest in a saguaro since before World War II.

“It was absolutely amazing when I got the first report,” said Kenneth Jacobson, raptor management coordinator for the department. “When we were able to get out there and see (the nest) from the ground and verify it was quite exciting.”

The nest was first reported by a member of the public, and Game & Fish flew over to confirm the report. Biologists say there are two bald eagles and an unknown number of eaglets in the nest, which is near a central Arizona reservoir.

“This is something biologists in Arizona have been aware of the possibility since the 1970s,” Jacobson said. “We’ve been looking for them, so finally finding one and seeing one is quite amazing since it’s been on our radar for a very long time.”

The only other record of a saguaro nest was in 1937, Jacobson said. In the 1970s, biologists found a mention to Kermit Lee of Lee’s Trading Post, who had reported large nests in saguaros along the lower Verde River.

“We’ve been keeping an eye on large saguaros for decades,” Jacobson said. “But all the ones that were seen with large nests had no documentation of egg laying or raising of young or any information like that.”

The department won’t disclose the location of the nest to protect the birds and their habitat.

“This is one of those things that is pretty exciting, but the last thing we want to do is draw a lot of attention to it,” Jacobson said. “If we get a lot of people coming out and checking it out we may end up inadvertently causing problems for their nesting attempts.”

The years of speculating are finally over for biologists like Jacobson, and confirmation is as thrilling as he expected.

“It’s been an 18-year trek for me, keeping my eye out for a bald eagle nest in a saguaro, so finally finding one is amazing,” Jacobson said in the department’s press release.