By Eilene Lyon
My partner and I sat in the Bass Tracker on the calm waters of Saguaro Lake – actually an impoundment of the Salt River near Scottsdale, Arizona – scanning the skies. In this narrow section, a sheer cliff rose ahead of us, and hills on both sides. Suddenly, a bald eagle bolted like a spear from above, aiming for an American coot, placidly oblivious to its impending doom.
The male eagle clutched his prize on top of a lakeside boulder. Soon his vice-grip beak was flinging feathers like a pillow fight gone bad, working his way to a fowl meal. After getting his fill, he seized the carcass and flapped off the rock until he’d achieved some height. Surely, we thought, he’d take it to the nearby cliff nest where the female and their nestling waited.
But no. Once again, as he’d done for months, he ignored them and flew away out of sight. Dang! What a deadbeat dad that bird turned out to be.
Before taking on this contract job to observe breeding eagles for Arizona Game and Fish (AGF), all nest watchers had to read up on bald eagle behavior. The standard story is that pairs mate for life, and both adults share responsibility for nest construction, incubation, and rearing the clutch of one to three nestlings. Once they’ve fledged, the parents spend roughly ten weeks teaching them to hunt before they become independent.
Sounds great in theory, but every animal, human or otherwise, has its own personality and quirks. With our domestic animal companions, we see that readily. It’s true in the wild as well. We tend to think: a mouse is a mouse is a mouse; a bear is a bear is a bear. We expect eagles will behave a certain way – then they don’t.
We started off with one assigned nest, which is the norm, but we discovered a second nest on our first trip out with our supervisor. AGF asked us to check on it, too. The first nest had been observed in previous years.
For some reason, this year the male decided not to participate in the breeding process once the egg(s) were fertilized. We watched as the female took sole responsibility for incubating. When hungry, she had to fly off and procure her own food. She selected a perch on a low cliff until she spotted a fish. She would nail her quarry on the first try nearly every time.
Her mate, on the other hand, lacked that skill. Every time we saw him dive for a fish, he got wet, not dinner. Sitting ducks were more his speed. AGF informed us that it can take five years for an eagle to learn to fish. But maybe it takes longer, or dare I say, never?
At our nest observation point one day, amazingly, it began snowing. Hard. Mrs. Eagle had flown off to hunt and was gone so long we reported it to HQ. They told us the eggs would no longer be viable in those conditions. We should switch over to observing Nest Two.
There couldn’t have been a bigger contrast. This eagle pair was in love. They did everything together, even…you know. By the way, it happens so fast that you really better not blink. Soon they had three voracious young to feed. Two is a better number.
Females are larger than males and eggs hatch in the order they are laid. If the first to hatch is female, and the last is male, well, he is likely toast. Eventually there were only two nestlings left. All the while, both adults fulfilled their roles as responsible bird parents. They showed no favoritism. The strong survive.
On a whim, we decided to return to Nest One. To our pleasant surprise, we found that an egg had hatched and there was a nestling. We began dividing our time between the two nests. We even hiked up a canyon one day to check on a third nest.
Papa Eagle at Nest One continued to ignore his mate and offspring, with one exception. An immature adult eagle appeared one day and tried to fly into the nest while Mama and Munchkin (as we called them) were in it. This bird may have been one of hers from a previous year, or maybe a young male looking for some action.
Either way, Mr. Eagle was having none of it. He came at the interloper in a full-on dive and knocked the juvie for a loop. The aerial combat went on for many minutes. Eventually the grappling, whirling pair disappeared beyond the hilltop.
We had many exciting moments amid endless hours of tedium during our four months of nest watching. Those hundreds of hours of eagle observation impressed one important lesson on us: When you’ve seen one, you haven’t seen them all.
Feature image: Sunrise on Saguaro Lake. Our primary task was actually to record human activities on the lake to determine if they impacted eagles. As far as we could tell they didn’t. (E. Lyon 2009)
For more information: Arizona Bald Eagle Nestwatch Program