Ospreys on the Northeast Cape Fear River

Ospreys are magnificent birds. Although they are found almost worldwide, they have become iconic in the lower Cape Fear region. Given many names— osprey, river hawk, sea hawk and fish hawk—our local university chose the name Seahawk for their mascot. A large sculpture of an osprey, or seahawk, by local sculptor Dumay Gorham is prominently displayed on campus.

Ospreys (Pandion haliaetus) are an ancient raptor. Fossil remains from 13 million years ago show they’ve changed little since then, indicating they they were so well suited to their environment that they haven’t needed to evolve.* They typically stay in our area for their nesting season, arriving in March and migrating south in August.

Ospreys can have a wingspan of up to six feet.

Observation © steve b, https://www.inaturalist. org/observations/101240658. No changes made.

Captain Doug Springer has spent 15 years leading tours on the Cape Fear River, most recently on his custom-built motorized catamaran, the Wilmington. We asked him to share some of his observations about this iconic bird.

“I’ve spent a lot of time on the Northeast Cape Fear River,” said Springer. “That’s where I got really interested in watching the osprey. At one time, we had about 18 nests in about a five-mile stretch of the Northeast Cape Fear, north of here, going up towards Castle Hayne. The river has clear dark water—perfect habitat for osprey. We’ve been watching the changes, and we’re down to probably seven nests.

“We’ve seen increases and now decreases, and I’m always trying to find out what’s going on. We saw the biggest change after Hurricane Florence, when all the nests but two were destroyed. It hit when some of the babies were still on the nest.”

This young fledgling osprey eagerly anticipates the return of its parent, who will be bringing it a fish. This nest is on Alligator Creek near Eagles Island. Osprey nests are always near water, because an osprey’s diet consists almost exclusively of live fish.

photo by Bryan Putnam, Art-Sublimina-Photography.com

What usually happens is, the parents come back first. Typically, it wouldn’t be an issue if the nest weren’t there. They’ll spend about two weeks building a new nest and then they’re right back on track. But another inherent trait of the osprey is that the first year, once the young birds have found a mate and come back, they will practice building nests. They’ll build two or three practice nests, but won’t raise chicks because they come back almost too late in the season.

“After Florence,” Springer said, “when all the parents came back, they all started practice building nests again instead of rebuilding. They built on bridges, on power lines, all different places. Only two of the nests raised young that year, so there were two seasons without any young being raised here.”

Adapting to the warmer climate

Springer notes seeing an adaptation to the warmer river. It’s been warmer than it’s ever been in recorded history.

Typically, the parents migrate away first. They depart at the end of August, leaving the young birds here. The young birds stay until they’re absolutely forced to leave, and what makes them leave is when the water turns cold, the fish go deep to stay warm and the birds’ food supply goes away.

Now that the river is warmer, the fish are available later in the season and so the birds try to stay here. We don’t fully know what the impact of this is. A small percentage make it through; others aren’t here at the end of the winter.

Support in the face of habitat loss

Ten years ago, the ospreys nested in the dead cypress, but those trees aren’t going to be there forever. Springer suggests we start scientifically putting platforms up in this colony of birds to see how receptive they are, since ospreys often nest on telephone poles, duck blinds and other types of manmade structures. Area property owners he’s spoken with are more than willing to have osprey platforms built on their property.

“I’d like to get the university involved, map out a program, and get artists in this community to design creative-looking platforms,” said Springer. “That would draw people up there who are interested in artwork as well as those wanting to see the birds. We could light it in the winter months, [when the osprey are away], as a draw to get people up into those areas.”

The osprey population has plummeted on the Northeast Cape Fear River over the last four years. People tell Springer they’re seeing a difference in migration patterns as well. A lot of the birds now stop in Florida instead of continuing on into Cuba and South America.

On global warming

On his boat tours, Springer talks with people about global warming, explaining his “take” on climate change.

“Mother Nature inherently recognizes change, whether it’s a cypress tree that sees the water getting fresher and tries to grow again, or an osprey modifying its migration period. Our alligator season is five weeks longer than it was ten years ago. Alligators love global warming. I’m convinced they’re going to start building power plants. They love it. But I say Mother Nature inherently recognizes change and then her instinct is to do something different. It may work or it may not. But she’s going to try to do different things.

“Our job as humans is to recognize change but also to recognize when change gets out of sync. We’re no longer seeing a nice sine wave of change. The world heats up and cools down, but it doesn’t happen exponentially unless something unusual (like a meteor strike) happens.

“When we see the world heating up quickly, we can try to learn the cause. If we can keep change in some sort of sine wave, we can try different things to adapt, and our chances of adapting will be so much better. If global warming scares you, which I understand, at least don’t deny yourself the opportunity to recognize the change around you, because it’s interesting.”

Suggestions for observing the world

For people who haven’t really thought about the ospreys around here, they are very much a part of us. If you want to start looking for change, and understand change, Springer suggests you find an osprey nest. Watch it, and write down when the birds return in the spring—likely about eight days before St. Patrick’s Day. Note the change you see, and put it on a calendar. When did they fledge the young birds out of the nest? How many fledglings were there? Did the fledglings stay here or did they leave? How long has it been since you last saw that young bird?

Get to know the birds. Name them. Have fun with it. See whether you can notice when they come back in the spring.

In addition to changes in osprey behavior, we are seeing the local alligator season being extended. Alligators used to go into hibernation when football season hit. Now, it’s about three weeks after. They also emerge earlier in the spring. The magic temperature for alligators is 70 degrees— that’s when they come out into the river. We are seeing more alligators in North Carolina than before.

This osprey pair has returned to the area and is about to begin nest rebuilding. Their nest is on a human-made platform. The female is on the right.

photo by Jack Spruill

If you aren’t following an osprey or alligator, observe a songbird in your backyard. Start taking notes on when you see that bird nesting, and note whether it’s different the following year. Count how many chicks they have. You might see the bird’s coloration changing. Anything you do look at is changing—there’s nothing that’s not.

Springer dreams of creating a Walden’s Pond type of experience on the river. He’d like to put a houseboat on the NE Cape Fear River and arrange for a couple of students to live there for a season to observe the ospreys and anything else they’d like to observe.

He does find that adults are becoming more receptive about hearing about global warming. “They’re hearing their kids talk about it, over and over, so it’s harder for them to assume the ostrich position. Let’s not be ostriches, let’s be ospreys. Let’s recognize change.”

If you’d like to go out on the river with Doug Springer, Wilmington Water Tours cruises on the Cape Fear River will resume on March 12, 2022. Learn more at https://wilmingtonwatertours.net.

See how climate change will reshape the range of the osprey, at https://www.audubon.org/field-guide/bird/osprey.

* Frank E. Zachos & Ulrich Schmolcke. “Archaeozoological records and distribution history of the osprey (Pandion haliaetus) in Central Europe” in The Journal of Ornithology, vol. 147 (2006).