Cormorants and Herons and Eagles, Oh My!  A Story of Drama Along the Fox River

For this month’s column, I’ve decided to recount an incredibly unique experience I had along the banks of the Fox River last October (2022) on one of my frequent visits to the river observation platform at the Hoover Forest Preserve in Yorkville.  As you might suspect, this experience revolved around the interaction of three different bird species: the Double-crested Cormorant (two individuals), the Great Blue Heron, and the Bald Eagle.  While all three species are common residents along our Fox River, they typically don’t spend much time interacting with each other.  This day was an exception though!

A Bucolic Start to the Day

As I hiked down to the river through the woods at the Hoover Forest Preserve, I had no idea that I was about to experience one of the biggest thrills of my lifetime of observing and photographing nature! When I arrived at the observation platform overlooking the Fox River, I was met by a typical scene for this time of year.

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A warm autumn day at the Fox River observation platform at the Hoover Forest Preserve. I’ve seen many incredible sights from here!

A flock of mallards was foraging among the small channels running through a stand of native American Water Willow (Justicia americana) plants located in front of the platform.  A few Canada Geese were swimming a little way downstream.  A Great Egret patrolled the far shore in search of fish while a Great Blue Heron hunted the river near the edges of the water willows.  A pair of Double-breasted Cormorants were swimming along the surface and occasionally diving in search of fish in the channel nearest to the platform.  All was seemingly quiet, peaceful, and harmonious among the residents of the river in the preserve.

A Subtle Change

As I sat quietly on the bench on the platform observing the birds in the river, I began to notice that the Great Blue Heron seemed to be paying a lot of attention to the Double Crested Cormorants.  The heron wasn’t particularly close to the cormorants and didn’t seem aggressive toward them, just very interested in their activities.  As the heron watched, the pair of cormorants ran along the surface of the river, taking off as they headed upstream.  They landed on an exposed rock about 200 yards upstream of the observation platform and began drying their wings (they don’t have the water repellant oils in their feathers that some waterfowl do) by spreading their wings as they stood on the rock.

Two Double-crested Cormorants perch on a rock in the Fox River that will soon be disputed territory! The bird on the right is drying his wings.

The heron kept a very close eye on the cormorants as they flew to their new perch on the rock upstream.  I thought the heron’s behavior was a little odd as I hadn’t seen one pay so much attention to other birds.  Normally, a hunting heron is the picture of concentration as it scans the water for a likely fish to target.  This one was distracted by the cormorants though, and took off to follow them upstream.  I watched as he landed about 100 feet from the rock the cormorants were perched on and began to apparently resume his fishing there.

A Brief Kerfuffle

My attention had returned to the waterfowl in front of the platform and I was photographing some of the ducks there when a loud squawk from the heron erupted upstream!  I looked and saw the heron chasing the cormorants off the rock they were perched on and then standing on the rock, loudly squawking at them as they frantically swam in circles around the angry heron! 

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A Great Blue Heron watches a Double-crested Cormorant circle the rock he evicted the cormorant from in the Fox River.
The cormorant was not happy!

The cormorants circled the rock a few times while the heron continued to angrily squawk at them before they decided to fly off to quieter environs with friendlier neighbors upstream.  The heron, seemingly proud of himself for chasing off the cormorants, stood boldly on the rock claiming it as his own. 

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The Great Blue Heron enjoys his brief time as King of the Rock!

Another Strange Occurrence

As I took a couple of pictures of the heron standing on the rock, he proceeded to do something that I had never seen a heron do before; he stepped off the rock back into the river.  Instead of wading away in typical heron fashion, he began to swim along in the flow of the river like a duck or goose, slowly paddling downstream.  I was amazed at this behavior and tried to get some pictures documenting it.  As the heron moved downstream, I focused my camera on the strange scene and was rewarded with some unbelievable pictures of what followed!

The Climax of the Day’s Mini-Drama

As I depressed the shutter button on my camera to get a picture of the swimming heron, a third actor entered the scene from above and to the right – an attacking Bald Eagle!  I was stunned to see this event unfolding in my viewfinder but had the presence of mind to keep the camera’s shutter button depressed to record the incredible scene!

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This is the first view I had of the Bald Eagle as it swooped in to attack the swimming Great Blue Heron! It was shocking to see this chain of events unfold through my camera’s viewfinder!
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The Bald Eagle makes his closest approach to the Great Blue Heron! Luckily for the heron, the eagle’s talons never seemed to find their mark!
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The Bald Eagle begins climbing away from the terrified Great Blue Heron after making a high-speed pass at the poor heron. These three pictures were all taken within the span of only a couple of seconds!

The eagle missed the heron as he flew past!  The shaken heron flew off to the sanctuary of the woods across the river while the eagle, seemingly angry at his failure, circled the river whistling and creating terror among the ducks and geese below.  What had previously been an idyllic scene became a cacophony of chaos among the terrified waterfowl.  Eventually, the eagle calmed down and landed on a tree across the river from me on the platform.  Quiet came over the scene again as the ducks, geese, egret, and heron had wisely vacated the area!

After the eagle attacked the heron, he circled the river in front of the platform a couple of times, whistling angrily and stirring up all the other birds in the area! He settled on this perch after a few minutes and things began to calm down

Lessons Learned and Conclusion

I never expected that a Bald Eagle would attack a full-grown Great Blue Heron.  As unbelievable as it was that the eagle pressed an attack on the heron, it was more unbelievable to me that I was there to witness it and even record it on camera!  I hadn’t seen the eagle before he came into my viewfinder, which probably turned out to be a good thing!  If had seen the beautiful raptor as he flew onto the scene, I would have probably tried to get pictures of him in the air, but then missing the attack!  That was a great stroke of luck!

I also researched what I witnessed and found the Bald Eagles do indeed very rarely prey on full grown Great Blue Herons, that Great Blue Herons do indeed very rarely swim like a duck instead of wading, and finally, that Great Blue Herons and Double-crested Cormorants very rarely do not get along and act aggressively toward one another!  None of these events are common at all.  The combination of them in one place within a five-minute period is probably close to a one-in-a-million longshot!  The odds of getting it all on camera have to be astronomical!

Once again, our wonderful Fox River provided an incredible opportunity to witness an amazing natural spectacle.  While I’ll probably never see anything like this again along the river, I almost always see something wonderful when I’m on one of my visits!

Until next time, get out and enjoy the fantastic sights and experiences our river affords.  You never know what you might see!

All photos were taken by Tom Schrader.