Where my blog comes to life.

DSC_0443At Wickiup Nature Center in Linn County, you can visit the physical embodiment of this blog: what I’m trying to do with words and pictures, they are doing in real life. Aquatic, terrestrial, and wetland habitats are accessible by well-maintained and marked trails. A beautiful, engaging building, and friendly, knowledgeable staff. Here is a place to learn, to make connections, and to have fun!

The wetland is not far from the parking area and entrance. A signboard points the way, and a wide, sturdy boardwalk allows you to get right out into the action. Up close and personal, no boots required! The central open-water area has several nesting structures, and dense cattails grow in a (presumably) shallower margin. We saw and heard waterfowl, blackbirds, and amphibians. Signboards aid identification and describe the ecology of the wetland. I’d describe this as a fairly typical freshwater marsh. I’ve seen quite a few similar wetlands around Iowa. A nice place to visit, but honestly, not exactly notable. No, something else makes this place really special.

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People. Connecting people to each other, and to the natural world, is the purpose of a nature center.

At Wickiup, the idea is to integrate this wetland with other habitats, via trails and signs and programs. The staff obviously carry that further, by teaching about the long view of geologic and human history. Visitors look into a prehistoric past, and engage today with activities to make a better tomorrow. The displays and programs invite us to think about other people, and other species, and how we can understand them better. Dioramas and sculpture and specimens provide “a sense of place.” Honey produced on-site connects us to the flowers and the bees and the bee keepers. A notice on the bulletin board asks us to be on the lookout for “Civet Cats,” so we can aid in a scientific study.   All the exhibits and programs reinforce the dual educational and preservation missions, and to invite visitors to be a part of the mission.

During my visit, they were readying for a celebration of the new natural playscape. It is filled with beauty and whimsy and invites you to enjoy fresh air and exercise and to explore. Nothing more hopeful or future-oriented than playing with our children!

Admittedly, this blog isn’t nearly as much fun, as a playscape. Hopefully, readers will nevertheless be inspired. Along the way, I try to teach little lessons, and share my passion, and ask questions. Perhaps readers will choose to visit a wetland or two, or share with others, or join in the work of preserving and studying our wetlands. Thanks for reading, and supporting my mission.

I’ll let Aldo Leopold have the last word (carved in rock, no less). Peace.

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Tale of the Swale

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American Toad, Anaxyrus americanus–the amphibian formerly known as Bufo americanus.

At the risk of repeating myself, let’s think again about hydrologic connections. While we’re at it, why not expand the thought to social connections as well? A visit to the E.C. Lipke Wetland in Plymouth County, and a recent presentation at the Tuesday Seminar series at Lakeside Lab, make my musings flow!

 

First, the literal connection: a ditch-like swale runs through the Lipke wetland site, connecting low spots on the floodplain (including nearby farm fields) to the adjacent Big Sioux River. Most of the time, water is draining from the adjacent fields, and flowing towards the river, through subsurface plumbing (drain tiles), ditches, and this swale. During times of “overbank flow,” when the river is above flood stage, water will spill out onto the floodplain, flowing all the way back onto the farm fields. The river and its floodplain are connected.

Now, the literary connection: two days after my visit to the Lipke Wetland, I heard Lisa Dill, of the University Of Delaware, give a talk entitled Forgotten River: Why Science Writing Matters to an audience at Iowa Lakeside Laboratory. Unbeknownst to me, this talk both encouraged us scientist-writers to tell stories (basically, to do what I’m attempting with this blog), and also describing her own project, writing about her family’s amazing adventure boating down the Missouri River, and interpreting the big water for us.

That epic journey started not far from the Lipke wetland, as it turns out. Lipke is about 17 miles (27 km) upstream from the confluence of the Little Sioux meeting the mighty Missouri River. Lisa’s family is from this area, and was already familiar with the river, and the people who live, play, or work on it. During her trip, and in researching the book she’s writing, Lisa also read historical accounts and interviewed scientists and other experts. She met and spoke with people who live on, and with, the river. No one book could possibly tell the story of a river as large and important as the Missouri, but this book is sure to provide a thoughtful and engaging perspective. I plan to get my copy when it is published!DSC_0333

In the meantime, let’s think about the Little Sioux, and the Missouri, and the swale, and the wetland…and yes, the adjacent wet areas in the farm fields…as all being part of a larger, linked  system. Truly, water flows around and around in this space. Most years, the lowest areas in the floodplain, cultivated or not, will have at least a little standing water in the spring. Some years, the floodplain will live up to its name, and much of this land will be under water. It behooves us to remember that anything sprayed or spread onto the ground could become part of these connected waters.

I observed many animals as I walked around, and they all live with this water, too: damselfly, crayfish, snails, geese, or that handsome toad pictured above. Our treatment of the land, our attempts to regulate the river, and anything we put in the water will affect both them and us. The old saying is true: we all live downstream.

The Bog That Wasn’t

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A Depression-era shelter, built by the Civilian Conservation Corps, overlooks Dead Man’s Lake. The Corps also built an observation tower nearby.

I was pretty excited to hear about Iowa’s only bog, noted as an important feature at Dead Man’s Lake at Pilot Knob State Park in Hancock County. Bogs are an amazing type of wetland, with interesting biota and water chemistry. The cool climate in northern Iowa, the lake formed by a glacier and situated in a sort of bowl raised above the surrounding land, and reports of a floating peat mat on the lake were all intriguing. But the big draw was an iconic bog species, the carnivorous plant Round-leaved Sundew (Drosera rotundifolia). This is the only spot in Iowa to find this “animal-eating plant,” and I wanted to see it!

So, several years ago, I took my Aquatic Ecology students from Iowa Lakeside Laboratory to the site. We braved the difficult crossing of the lake margin to get onto the floating (quaking!!) peat mat, and after a short search found the plant. I went back the following year with that class, and again we found Sundew. Then last year (2017) we saw no sign of the plant. And…what about this year??

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We roamed about freely on the peat mat, searching for the elusive Sundew…

We spent considerable time searching, but without success. The students and I had a great conversation about why we didn’t find the plant, with one possibility being that the plant was not yet out and about for the year (winter had hung on late in northern Iowa this year). We speculated about whether we would find the plant if we visited later, or whether the plant was now simply missing from the site (a disappointing development if true!).

What we did find was the bog-like peat, a buildup of dead, undecomposed plants such as Sphagnum moss accumulated over many years. (Earlier measurement of a mat 3-meters thick would take about 2,000 years to accumulate at typical rates). On the mat we found, growing out of the moss, a dense collection of sedges, cattails, ferns, and wildflowers. Scattered, stunted small trees gamely tried to grow on the unstable substrate. That peat mat not only offers no soil, and bounces like a waterbed, it is saturated with water of unusual properties.

 

 

Let’s start with the color…rather like iced tea, a cloudy brown. This is typical of water in a bog, darkened by tannins leached from the peat. And despite a sunny, uncomfortably hot day, the water was also iced-tea cold: a mere 1 meter (3.3 feet) down, the water was a chilly 10 degrees Celsius (50 F). Also, as might be expected in a bog, the water was acidic: pH values ranged among the different samples but averaged 5.426. Specific conductivity (ability to conduct electricity) was 76 micro Siemens, much less than at many fens I’ve encountered.

“But Paul,” you say. “Are all these observations consistent with a fen, or a bog? How are they distinguished, anyway?” Those are more complicated questions than might be supposed at first! But really, is it any surprise that categorizing various types of wetland ecosystems might be challenging? Deciding what set of attributes define a particular biological species makes taxonomists engage in fisticuffs. Drawing a line around a wetland ecosystem is a complex process, requiring a lengthy manual and specialized training. Just the catalog of different wetland ecosystems, the widely regarded Cowardin et al (1979) publication “Classification of Wetlands and Deepwater Habitats of the United States,” is 142 pages long (!). So, yes, this is a complicated question.

Given the caveat that reasonable scientists could see things differently, I’ll say that by most definitions, this site would be called a fen, not a bog.  Both types of wetland build up peat. Both are perennially wet. Chemistry can vary over quite a range in each system, but we are more comfortably within the range of fen than bog. Surely, bogs are acidic (low pH), but fens can be acidic too. I suspect low nitrogen concentration in the water—hence the need for a plant to “eat” animals as a source of nitrogen—but this can be true in a “poor fen.”

Further study of the hydrology, in particular a water budget to estimate how much water comes from the sky as opposed to groundwater, would be helpful. I’d like more tests on the water chemistry as well. I hinted to my students that this work would make a EXCELLENT Master’s Thesis (not sure any of them will rush to do the work, but a guy can hope!). Bog or fen, this is a curious and fascinating wetland, and beautiful too. Don’t get bogged down in the details of ecosystem classification, or offended by what I choose to call it. Just call it one of our 99 wonderful Iowa wetlands, and thanks for visiting with me.

*EDIT: the “Blue Flag Iris” in the photo below is identified as Iris versicolor. That common name is also used for a related species, I. virginica. A sharp-eyed reader pointed out the similarity, and provided a link to a web page describing the two species…might have a look!

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Blue Flag Iris (Iris versicolor*), a most photogenic plant

Production Junction

DSC_0319At the Floyd River Wildlife Complex A in Sioux County, at the junction of highway and river, I found signs of Ecological (Trophic) Production. I’ll use this wetland to encourage professional networking; we’ll ponder this solar-powered planet of ours; and I’ll talk about highway projects. And away we go!

I heard about this wetland from my friend and colleague Todd who lives not far from the site. Also, I know a bit about projects such as this from other colleagues, including several who studied a bunch of them (more on that later). As I have suggested in other posts about my journey around Iowa, personal recommendations—and hearing the stories behind the wetlands—is really helpful. Please join the conversation!

This wetland is located along the Floyd River, but is also adjacent to State Route 60. In fact, the wetland was built by the state highway department as mitigation for impacts to existing wetlands during highway construction projects. As I described in posts about Brush Creek and Indian Slough, the Federal law protecting wetlands (Section 404 of the Clean Water Act) allows for permission to “mitigate” impacts through a legal contract. In this case, the state highway department was required by law to build this wetland. Would you like to build a wetland, too? Here’s a piece of advice: make sure to provide water. One possible source of water is an adjacent river, if available. A notch in the riverbank provides a hydrologic connection to the Floyd River.

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In Iowa, your river water will almost certainly contain nutrients like nitrates, and they will act as a fertilizer for the plants and algae in your wetland. (They will also contribute to microbial processes like denitrification, but that’s another story). Generally, plant growth is slow and steady, imperceptible and relentless. We might find it difficult to visualize the photosynthesis and resulting production of plant biomass; we might even forget about this most basic energy conversion process. That’s unfortunate, because essentially all life on Earth is powered by the Sun, as plants and algae convert radiant energy (light) to biological energy (food) by photosynthesis.

One way to estimate this energy conversion of photosynthesis is to cut down plants, burn them, and measure the heat energy given off during combustion. It is however an indirect measure, since you can’t harvest and measure lost energy, such as is used in the plant’s own metabolism. Think of overall photosynthesis as Gross pay in a worker’s earnings, compared to the Net (“take-home”) pay of standing crop (biomass harvested). Ecologists estimate gross primary production (GPP) and net primary production (NPP) in ecosystem studies such as “trophic-dynamics.” Wouldn’t it be nice to directly observe the photosynthesis itself?

Actually, you may have observed, and even quantified, photosynthesis yourself…as a child in school. A common (and fun) way to study photosynthesis is using an aquatic plant like Waterweed (Elodea) in a tank or test tube, watching bubbles formed by the plant as it photosynthesizes; those bubbles are oxygen, a byproduct of photosynthesis. Want to know the effects of fertilizer, temperature, light color or intensity, or some other variable on photosynthesis? Count bubbles!DSC_0327

At Floyd River, I observed floating filamentous algae with trapped bubbles forming in the bright sun. Photosynthesis! Primary Production! A wetland with a green, active solar-energy-conversion system! Actually, certain wetlands are among the world’s most productive ecosystems. Plenty of water, nutrients, and off we go. And that serves as the base of a food chain, with plant-eating grazers, herbivore-eating carnivores, and sometimes additional levels beyond. I observed snails, backswimmers, tadpoles, small fish, and waterfowl. The wetland teemed with life, and the water spread around a bend along the river. A productive wetland.

The time frame required for wetland development, the criteria we should use to measure mitigation success, and who will be keeping score of those parameters are important considerations. A decade ago, a team of Iowa scientists compared highway mitigation wetlands with natural reference wetlands, and found similar ecological performance in both types of wetlands. I suggest caution in generalizing beyond that one study. In particular, I worry that wetlands built by others, for other purposes, may not have as high quality of design nor construction, as those built by the Highway Department. I strongly suspect that the highway wetlands had at least some monitoring and active management, while I worry that many mitigation wetlands are built and abandoned to their own devices..which seldom ends well.

Floyd River appears productive and functional. Can all of our wetland projects achieve this status? Perhaps we can, and should, inspect our constructed wetlands, and expect them to perform to “engineering standards.” What would you like in a constructed or restored wetland? Consider leaving a comment. Thanks for reading…DSC_0326

A Wetland of Black and Green

DSC_0145This blog entry is about my visit to Rossow Prairie in Webster County, and the apparent aftermath of a fire there.

“But Paul,” you say. “Isn’t this blog about wetlands? Why discuss fire??” Because, fire CAN be important in wetlands! Most famously, the amazing wetland landscape of south Florida known as the everglades, or the northern peat bogs, have regular fires…and the biota of those wetlands (including humans) have had to adapt to the effects. The Association of State Wetland Managers has a nice review.

Unlike the landscape-level wetlands like the Everglades or the vast northern peatlands, Rossow is a small slough wetland in a larger tallgrass prairie landscape. The prairie is, of course, a fire-dominated (fire-dependent!) biome. Iowa’s prairies always burned, and the wetlands within them—marsh, slough, fen, whatever—would have certainly burned, too.  But how does a prairie fire compare to a wetland fire?

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Last year’s blackend stems and recent, green growth

The similarities are actually quite striking. Prairies and these wetlands are both dominated by tall, herbaceous plants, especially grass-like “graminoids” and are dominated by perennials whose roots (or underground stems) would send up new shoots after a fire. The soil is unlikely to burn hot—usually only the very surface burns. Seeds in the soil can germinate in the open, sunny ground after the burn. The soil gets a boost of available nutrients: chemicals previously locked up in plant tissues are now released into the soil through the ash.

Plants have less competition after a burn…fires opens up the space, knocking back the dominant species (at least for a while, perhaps). Wetland managers concerned about weedy plants may use fire as a tool for weed control. Woody plants for example can be invasive in these habitats, but fire is hard on them especially (their active growth tissues are vulnerable to heat damage). So, “woody encroachment” may be lessened after fire.

 

 

The fire in this wetland is a “spill-over” from a fire set intentionally by the land managers in the adjacent uplands. Matt from the County Conservation Board mentioned their use of so-called “prescribed burns” as a tool in the prairie, for some of the same effects I just described for wetlands; and the fire moved into the wetland, potentially giving those very benefits to our slough. Cattails (Typha) in particular tend to dominate a shallow-water wetland such as this, and perhaps other species will fare better after this fire.

Time will tell. The site is undergoing improvements to the water-control structure; such infrastructure is vital to managing a system, but must be maintained or repaired from time-to-time. But for now, I saw a more open marsh, and it is verdant in the extreme. Hard-stem Bulrushes (Schoenoplectus acutus), sedges (Carex) and wildflowers like (possibly, Swamp) Milkweed (Asclepias incarnata??) were starting to come up and were a vibrant green. Birds such as Marsh wrens (Cistothorus palustris), Red-winged Blackbirds (Agelaius phoeniceus), and Common Yellowthroats (Geothlypis trichas) flitted about and scolded me as I sloshed about. A local resident who chatted with me as I was leaving, mentioned that he enjoyed the variety of waterfowl he has observed at the site.

 

 

If I return to this site, will I see more of these species, or perhaps others? How would the biota recover from this type of disturbance? How would the fire effects be different in this late, cold, wet spring in this part of Iowa? So many “burning” questions! Feel free to leave your thoughts in the comments. Thanks for visiting…

 

When is a wetland “done?”

DSC_0278People are building wetlands. As a legal requirement for mitigation of impacts (e.g., to replace wetlands destroyed by a highway project, as in Jasper County or Louisa County), or to provide habitat for waterfowl, or to clean the water, or…for money…we are now in the business of creating (or, re-creating) wetland ecosystems. I visited the 1330-acre (540 hectare) Owego Wetland complex in Woodbury County with my Aquatic Ecology class from the Iowa Lakeside Laboratory field station. The site lies in a floodplain and was previously farmed; it also contained the now-defunct town of Owego. By virtue of size, variety of habitats contained, and position, it is an important area for birds.  All of this beauty and ecological value exists in stark contrast to the considerable alterations to the land. The wetland project began 20 years ago (1998). The project naturally involved many workers across a variety of agencies (as indicated in the sign, pictured above).

DSC_0274We had a good visit, but my students still had a lot of questions afterwards. Much of the discussion centered around the topic of wetland creation or restoration. They wanted to know how we might go about creating an ecosystem, and when it might be “done,” i.e. more-or-less appearing and functioning as a wetland ecosystem should. These are profound questions! The community of wetland scientists have been working on this for years, and I can’t answer it definitively even now. But here are a few considerations…and pretty pictures, too.

First, naturally, is hydrology. For your “wetland” to have any chance of a system worthy of the name, you must have water! Different systems (fen, marsh, slough, bottomland forest) will have different depths and timing of standing water or of soil saturation. Our visit was to a deep area near one of the northern parking lots, and it appeared to have at least knee-deep water at least most of the time. Having appropriate hydrology such as this, is necessary for anything else to happen.

Within hours of flooding, the soil begins to change. Water drives out oxygen in the soil, and chemical changes proceed (remember so-called “redox” or oxidation-reduction reactions from a chemistry class?). Eventually the soil has changed such that a reduced form of sulfur is produced; human noses are quite sensitive to the “rotten egg” odor. We smelled this at Owego as we “mucked about,” disturbing the substrate. But other characteristics may not change so quickly: my students remarked at a difference beneath our feet. As we walked around the margin of the wetland, a thin layer of squishy and slimy organic materials was noticeable as we walked; yet beneath that was a surprisingly solid, mineral soil. That terra firma might have been compacted over years of working the land for farming, or during the construction of the wetland; but in any case, students noted that it did not have the soft texture that draws us in—literally, as we sink into soft mud—like in a natural wetland. So, soil texture (and perhaps, color characteristics and certain other chemistry) may take many years to develop.

DSC_0289And what about the life in the wetland? Microorganisms (bacteria, fungi, algae) no doubt float or blow in, rapidly growing within days of flooding the site. Insects move around widely, and will lay eggs in appropriate habitats not long after; we saw many adult dragonflies and damselflies in flight that day. The water will quickly be teeming with insect larvae; a few weeks later you’ll see the emerged adults. All of this can certainly happen in the first season, and draw waterfowl thereafter. Certain ducks strain the water for small food items, and as they move between wetlands they bring much seeds, eggs, and other species attached to their bodies…or passing through their bodies…to add to the biological diversity. And plants will find their way, too, in some cases literally blowing on the wind. We saw a healthy stand of Cattail (Typha) of course, and it will colonize almost any wetland (or roadside ditch, or any possible habitat) quite rapidly. Other plants may take longer to establish, such as the Spikerush (Eleocharis) or Arrowhead (Saggitaria) we saw on the edge of the wetland. It’s possible that these were intentionally introduced when this wetland was built, but it is also likely that at least some were present in the soil “seed bank,” because a memory of a wetland can linger in a spot, despite human disturbance.

DSC_0294Back on campus, we analyzed samples of soil and water, and thought about what they tell us. This was a good complement to a reading we discussed, examining wetland “success” and time to establishment in human-made wetlands in Illinois. It seems obvious to me that such systematic monitoring and analyses of built wetlands is the only way to know the state of the art, and “lessons learned” from our work. And yet, despite decades of such activity (including wetlands built as a legal requirement in the mitigation process), we don’t have the knowledge base we need, in my opinion. Surely we need to ask if a particular built wetland has water, plants (but not weeds), and is sufficiently large. Surprisingly, we can’t even assure those basic requirements in mitigation monitoring, because it just isn’t required in many cases. And beyond the basics, as a question of science and engineering, we need (but lack) an organized system to assess the development of wetlands and make corrections as needed to individual systems. And we need a way to consistently and routinely report back the lessons learned from the individual sites, to improve our technique.

During our discussion, students asked questions about “wetland health,” using an analogy to the human body. I challenged them to expand that thought. So a child of various ages is supposed to have certain anatomy, physiology, and behavior to be considered “healthy” (within certain percentage ranges, such as height or weight on a growth chart). The physician may make a diagnosis or suggest a change in the child’s routine if the various parameters are inappropriate. Now, what would the “growth chart” or “well-baby checkup” checklist for a wetland include? What diagnostic techniques would we use to check against the list? Who will be the “wetland healthcare professional” and when will they perform the “examination?” Answering such questions is important, and we do have some techniques being developed to do this work. I hope we can continue that work, and make sure our wetlands are “done,” ecologically. Perhaps some of my students will see this through…

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The Wetland Remembers When

DSC_0256Visiting Little Rock River Wildlife Area in Lyon County called to mind the old country tune “The Song Remembers When” by Trisha Yearwood (Edit: not Martina McBride, as originally posted…sorry!). It’s a melancholy tale of lost love, and played in my head as I was walking on ground that surely had an ecological memory, of a wetland now gone.

This story needed to be told eventually on this blog. Upon hearing about my plan to profile a wetland in each of Iowa’s 99 counties, I was often asked “will you be able to find a wetland in every county??” Actually, my biggest concern was access: would there be a wetland on public property, or where I would be granted permission to visit? But what about the wetlands that simply aren’t there?? I knew at some point, we needed to talk about wetlands lost through human action (filling or draining the wet ground). It’s an all-too-familiar story across Iowa, where over 90% of wetland area has been lost. And my observations suggest that, although we do build wetlands, we are not finished removing them, either.

DSC_0257At this particular location, I found prairie and a food plot for wildlife (standing corn from last year) on the public ground. At the base of a nearby slope was a wet area, bisected by the fence marking the property line between county land and a recently-plowed farm field. This fence ran straight through what I believe was historically a wetland. On one side, we had grass, mostly matted down and silted; a layer of algae,  mostly dried and bleached white. In the farm field on the other side, we had…mud. Black, rich, well-plowed mud. Deer and bird prints dot the sticky wet surface.

 

Back on the public ground, at a similar elevation, I noted a wet area bisected by tire tracks. The vehicle had obviously sank low in this other wet spot, leaving deep ruts from the tires. A few scattered wetland plants (sedges, dock, cocklebur) grew from the bare mud. In the deep tire ruts, in the open water, swam familiar amphibian larvae.

“But Paul,” you say. “How can those tadpoles/pollywogs survive when that water dries up, as it soon surely must?” Indeed, these little black tadpoles must develop quickly—and so they do! Unlike our frog tadpoles which can stay larval for years, these American Toads (Anaxyrus americanus) will grow legs, lose their tail, and leave the water in perhaps two months.

 

So, this might be a challenging place to live. A short-lived “emphemeral” habitat with standing water for a few weeks to (at most) months. It’s also likely that historically, the spot would flood some years and not others—we’ve discussed variable or intermittent hydrology in other posts. This naturally-variable habitat has then, at this spot, been modified by humans—thus adding new challenges to the ecosystem. We might even ask,  have we in some sense “broken” the system beyond repair, or could it somehow still function, ecologically? Despite whatever modifications we make to the habitat…the memory of wetland persists. The soil characteristics, the soggy conditions, and the biota all remember. Insects, algae, and even amphibians can successfully inhabit this place. These are memories worth preserving, and when possible, recalling and celebrating.