wetland restoration | The Prairie Ecologist

After many years of wanting to, we finally installed some solar-powered pumps and livestock water tanks in our family prairie. (Thanks to the U.S. Fish and Wildlife Service and Nebraska Game and Parks for providing cost-share money!) Those two water tanks give the cattle nice cool clean water to drink and allow us more flexibility in the way we design our grazing each year. Most importantly, they allow us to exclude the pond/wetland from grazing so it can start to function as a wetland rather than as a big mud hole for cattle to stand around in.

Because we’ve had good rains this year, the wetland has been pretty full. That’s nice, but it has also prevented much of the wetland-edge seed I planted from germinating and growing. Despite that, the recovery of the wetland is well underway. There is now grass growing right to the water’s edge and arrowhead and other emergent plants are starting to appear in shallow water. I’ve been spraying the few reed canarygrass plants growing nearby in the hope of preventing that invasive species from taking over the margins of the wetland, and hopefully I can get some more diverse wetland plants to establish there instead.

The pond/wetland at the Helzer family prairie with abundant arrowhead (Sagittaria sp.) in the shallows.

My daughter and I went for a walk at the prairie over the weekend and visited the wetland to see what was happening. As I waded into the shallow water to take the above photo, leopard frogs scattered from my footsteps and red-winged blackbirds scolded me for encroaching upon their territories – very good signs of recovery. However, looking more closely at the arrowhead plants poking through the water, I found even more evidence of new life.

Abandoned exoskeletons of damselfly nymphs were littered around the wetland.

Adult damselflies fluttered around everywhere, and many of them had apparently just appeared on the scene because the larval exoskeletons they’d just emerged from were stuck to leaves and stems all over the place.

While I was too late to see the actual emergence of the damselflies, I did manage to find a green darner dragonfly that had just popped out of its larval skeleton and was fluttering its wings and waiting for its body to dry and harden. I snapped a few pictures of it in place and then carried it over to Anna so she could get a good look at it.

A green darner dragonfly and the larval exoskeleton it had only recently escaped from.

Anna enjoyed getting a close-up view of the dragonfly and even posed for a photo with it.

After we became a little better acquainted with the new dragonfly, we set it safely on a fence post so it could finish hardening up in the warm sun. I took a few more quick photos of it on the post and then left it alone. It was gratifying to see other dragonfly species zipping around nearby too – I’m hoping that’s a sign that a number of other aquatic invertebrates are also colonizing our recovering wetland. It should be fun to watch the changes in the coming years.

Our new friend on the top of a fence post.

This week, I present four photographs from one of the timelapse cameras along a restored wetland in our Platte River Prairies. All four photographs were taken automatically by the camera, and none are particularly striking images, artistically speaking.

Nice sales job, eh?

Despite their quality as images, or lack thereof, they are very meaningful photographs to me. In fact, the two photos of least photographic quality are actually the two I like best because they tell a story I’ve been hoping for since we first started the wetland restoration project more than 10 years ago.

Canada geese, some wigeon, and a few other ducks sit on the restored wetland in March of this year. This is a common sight, and a good one, but I was always hoping for more than just ducks and geese to use the wetland.

When we first started talking about converting a long sand pit lake (left over after sand and gravel mining operations from early last century) into something different, we had several objectives. Those included:

– removing the trees around the edge of the site to improve habitat for open-grassland and wetland wildlife species.

– providing shallow stream and wetland habitat for fish, amphibians, reptiles, invertebrates (including mussels), and other species.

– restoring diverse plant communities including emergent wetland, wet meadow, wet-mesic, and upland sand prairie communities.

– providing habitat for migratory whooping and sandhill cranes and many other waterbird species with similar habitat requirements.

The first three objectives were pretty easy, and we’ve seen abundant evidence of success. In terms of bird habitat, we’ve always had great utilization of the site by ducks, geese, herons, snipe and other birds during both migration and breeding season. But no cranes.

Until this spring.

The chance that one of (approximately) 260 whooping cranes will ever land in this particular wetland is very remote, but I have been expecting to see sandhill cranes using the site; if not for overnight roosting habitat, at least as a place to feed and loaf during the day. After all, there are hundreds of thousands of sandhill cranes here each spring – surely some of them should see this as an attractive place to hang out now and then. And if we see sandhill cranes using the site, we can reasonably assume that it’s suitable for whooping cranes too (though that’s not universally true).

However, during the 10 years since we started the restoration work, I’ve been looking in vain for a crane of any sort, or even tracks that would indicate they’d been there. Nothing. Last year, we had timelapse cameras up during the spring crane migration season but they malfunctioned and didn’t give me any evidence one way or the other. But this year, I finally got what I wanted.

Three sandhill cranes stand in the middle of the wetland on March 8 of this year. You can click on the photo to see a larger version of it.

I downloaded images from the cameras in mid-March and immediately scanned through them in the truck, hoping to see some evidence of crane use and – there they were! Three sandhill cranes showed up in multiple photos over the period of a couple weeks. Most of the photos were daytime photos, but it also appears they roosted overnight at least a few times, standing in the shallow water. Three cranes is certainly not evidence that we’ve added significantly to bird conservation, but it is evidence that our wetland isn’t completely abhorrent to cranes – and that’s a good start.

Then, as I kept looking through the images, I got an even better surprise. Late in the evening on March 11, there was a whole flock of cranes standing in the shallow wetland, apparently preparing to roost. Even better, the camera picked them up again early the next morning – pretty solid evidence that they roosted overnight. It only happened once (through mid-March) but I’ll take it!

A flock of 70-80 sandhill cranes stands in shallow water at 7pm on March 11.

At 7am the next morning, the cranes are still there – maybe more of them, in fact. Our first real crane roost… that we know of.

The pictures aren’t of terrific quality. They were taken by a camera set to fire every hour on the hour (during daylight hours) and low light and wind combined to the images a little blurry. Nevertheless, I think they’re pretty great photos.

Of course, now that I’ve gotten my evidence of crane use, my scientist brain is kicking in and asking questions. Why did the cranes only roost one night? Why that particular night? Why did they pick that particular part of the wetland?

And, there’s one more question my brain is asking, which I’m trying to ignore because I don’t think it’ll ever happen.

…Will we ever see a big white crane in one of those photos?

The Prairie Ecologist

Essays, photos, and discussion about prairie ecology, restoration, and management

Tag Archives: wetland restoration

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