North Minneapolis Heron Rookery Turmoil

Spring of 2026 started off well. The city began seeing herons arrive mid-March. The Mississippi National River and Recreation Area had planned to host their annual “Welcome Back the Herons” event at Marshall Terrace Park and I signed up as a volunteer with a scope on the river. I have to say that it’s way more fun to work that event as a volunteer and not paid staff in government pants.

March 21 had herons industriously refurbishing nests.

I headed out a week prior with a friend who had never seen the rookery to scout for the event. While there, someone mentioned a bald eagle was trying to build a nest on the island. I didn’t see anything that looked big enough for a bald eagle nest. Someone pointed to what they thought it was, but in my scope I could see that it was three heron nests clustered together. But there were about three dozen great blue herons working on nests and about 50 cormorants settling into the nests. I wondered if by the time the egrets arrive if there would be any space left for them.

A bald eagle flew in a couple of times, but every time that they did, the peregrines nesting on the nearby power plant chased them off. I’ve seen eagles hang out on the islands in early spring and once the peregrines are ready to start nesting they don’t tolerate them. I thought it was exciting that the herons were moving back and maybe a few were as the Marshall Terrace Park rookery was getting crowded.

The next day, I headed to Mississippi Gateway Regional Park at Coon Rapids Dam. Pre pandemic there was a rookery up there, but the birds abandoned it. After I finished my program, staff and volunteers told me that herons at started building a nest up there again.

I did a segment on Friday morning on MPR talking about the event and the peregrines chasing off the eagle. My friend Nina messaged me on Instagram saying that they eagles were trying to build a nest and had some great shots of the peregrines coming in for an attack.

Saturday morning I arrived for the event and my friend Lisa who is now running it came over and said, “There are no herons. There are no cormorants.”

Sometimes birds are gonna bird. It reminded me of one of my first tours to go see about 40,000 tundra swans and only four were present. I headed own to the river. All the cormorants were in the water and not on the nests. Herons were nowhere to be seen, not even loafing on the shores of the Mississippi River. The island was covered in empty heron and cormorant nests and one much larger nest with two bald eagles perched near it. Indeed, the eagles had built up the nest. I wondered if the peregrines decided to leave them alone or got tired of chasing them and decided to nest elsewhere.

Herons and cormorants in the air when the eagles and peregrines have their aerial battles.

Eventually, the eagles took off and after they did the cormorants flew around the island and after about 15 minutes, one by one, they each settled on a nest. Then, just as the program was supposed to start at 11 am, three dozen great blue herons flew in from east and started to land on the nests. It was an incredible sight.

Periodically, the eagles would try to fly back with a stick and every the peregrines chased them out. Maybe they were sleeping or hunting when I arrived and that’s why the eagles had a chance on the island. But the entire time I was there, the peregrines chased them. And when the dynamic aerial battles happened, it sent the herons and the cormorants into the air. Craig Mullenbach got a great shot of a peregrine escorting the eagle out.

I don’t know what’s going to happen to this rookery this spring. Will the peregrines be annoying enough neighbors that the eagles will give up? Will the constant bickering of predators make the cormorants and herons abandon the island? Will the eagles just tough it out? Will the herons all move to Coon Rapids Dam? The original island that host the rookery before the North Minneapolis tornado has grown back…will some of the birds move there? Who knows, only time will tell, but it’s certainly an exciting spring at the rookery.

But it’s incredible that habitat on the Mississippi River in North Minneapolis is so valued by so many charismatic birds.