ES: Could you please tell me about the prairie pothole region, what formed it, and its current state today?
Reynolds: The area where our research and investigations are primarily involved with are what’s commonly known as the prairie pothole region of North America. The prairie pothole region was formed primarily by a recent glacial episode. And then the glaciers retreated, or began retreating beginning about 10,000 years ago. Glacial activity moved across the landscape, primarily from the north central part of North America. Basically it acted like a large bull dozer and gouged out areas. As it advanced, it pulled till, rocks, soil, and other material into the glacial ice and of course it all mixed up. And then as the glaciers retreated, they left a topography that’s generally very rich in small wetlands. There’s a number of ways that these wetlands were formed, very complicated, geological kinds of processes. But primarily, as the material in the glacier slumped, you got kind of an undulating topography with lots of small depressions in-between the hills. And also, there’s lots of gouging and scraping activity as well that created wetlands. And so the area is unique, in that you’ve got a pretty much open grassland type of landscape with numerous small, shallow wetlands that typically number as high as 100 per square mile in many areas. And most of the wetlands are temporary or seasonal in nature, probably in the neighborhood of 85-90% of them. Particularly, what this means is that they acquire water from snow melt in the spring, and during significant precipitation events. But then they tend to dry out quite quickly, over the period of a few weeks or several months. And normally by the end of the growing season, say late August, most of these wetlands are dry again. In some years they retain water all year long. But for the most part, they tend to accumulate water in the spring and dry out in the late summer and early fall. As a result of that, they recycle their nutrients very quickly, unlike large lakes that become kind of stagnant and stale biologically, these small wetlands, because they recycle the nutrients and they’re not bound up in the wetland itself for long periods of time, they’re extremely productive. And so this area is preferred by many waterfowl and other wetland birds, that not only use the wetlands for migration, but primarily for nesting as well. The highest density of waterfowl breeding pairs for such a large area in the world. Certainly in North America, only rivaled by some dense areas in Alaska. And also for breeding shore birds and other types of marsh birds that find these nutrient-rich wetlands are advantageous for their breeding activity, the high-end nutrients not only for the adults, but also for the young. As far as the recent threats to the area, most of the prairie pothole region in the US, and I’m going to speak primarily about the US portion because about 2/3 of the prairie pothole region is in Canada, and about 1/3 is in the U.S. some of the things that I’m going to talk about are certainly similar across the border. But about 95% of the prairie pothole region is owned by private ownership. And most of it. the vast majority of that area, is primarily used for agricultural production, either crop production or beef production. In the case of beef production, the grass is left on the landscape and it’s grazed by cattle. In the case of crop production, the land is broken up, much of it going back to the late 1800s or early 1900s. This breaking up accelerated after the second world war, when large machinery became available. And it continues today. And once the land is broken, it really never can be native prairie again, at least not in our lifetimes. So the loss of grassland to cropland is one concern. And then the other one is the crop production increases. There’s a lot of pressure to drain the small wetlands, because they’re small and shallow. They’re easy to drain. And to turn those wetlands also into crop production. And once those wetlands are drained, it’s very difficult to ever restore them. So you lose the wetland component and the grassland component in those situations. And it’s estimated that about 1/2 of the small, shallow wetlands in the North and South Dakota have been drained for agricultural production. And when you get over to Minnesota and Iowa, upwards of +95% of the small, shallow wetlands have been drained, and virtually all of the grassland in those two states have been converted to cropland. And so, from a bird’s standpoint, birds that depend on that type of landscape for successful reproduction, that change in the landscape has a negative influence on their populations. Waterfowl for instance, the five most common species of ducks, mallards, pentails, gadwalls, bluewinged teal, and northern shovelers, those are the five most common nesting duck species in this area. They all depend on the wetlands for food and cover. But the females nest in the uplands. So for these upland nesting duck species, the loss of wetlands and upland combined has a tremendous impact on their ability to recruit new young into the population. Some of the work that I’ve been involved in, and the shop that I supervise, has been in basically trying to model the impact of the remaining wetlands in terms of the carrying capacity of waterfowl. And so what we’ve done is develop models from survey data in which we can predict how many breeding pairs of ducks might be associated with any particular wetland on the landscape over a period of years. Because in some years these wetlands are dry, in other years they’re overfull with water. So that’s a very dynamic system, you need to take into account this temporal variation that occurs. There’s also a lot of geographic variation, and so our models include that. And we can predict virtually any wetland out there, how many breeding pairs of ducks it might have tracked on a long term, average basis. And we can assess further loss or restoration of these wetlands and what kind of impact that will have on the carrying capacity for breeding ducks. We’ve also been involved in studying certain farm programs, such as the Conservation Reserve Program, which basically pays land owners a standard rental rate to convert cropland back to grassland. And what we found is, from the prairie nesting duck standpoint, that about 2 million additional breeding ducks are raised as a result of having CRP in the prairie pothole region over what would have been raised otherwise. So this is a net gain in productivity on an annual basis of about 2 million. That’s pretty substantial. Our models also show us what kind of impact we would expect if we lost a substantial number of the small shallow wetlands. And one of the issues that has been raised by the farm organizations is to exempt these small shallow wetlands from swampbuster provisions of the Farm Bill. And under the current Farm Bill, if a land owner takes part in the Farm Bill, they can’t drain their wetlands if they haven’t already been drained prior to the 1985 Farm Bill when swamp buster was initiated. And so as a result of those swampbuster provisions, a number of land owners have campaigned through many of the farm organizations to have an exemption for these small, shallow wetlands that they consider “mudholes” and of no value to anything. We just want to be able to put our plows down in there and turn them into cropland. So what we’ve done is used some of our models to assess the impact. And if we lost all of the temporary and seasonal wetlands which could be cropped in cropland alone, we would be looking at about a 50% decline in the carrying capacity of breeding waterfowl in the United States alone.
ES: For the benefit of our listeners, what do you mean by carrying capacity.
Reynolds: Yeah, that’s kind of an illusive term, because we don’t really know what the maximum carrying capacity is. But we can look at the average number of ducks that the landscape has carried over a period of time. And that’s the best way we can assess that. And so in wet years, there are a lot more of these wetlands that have water in them, so the carrying capacity, or the number of breeding pairs, that can settle in this area will be elevated. In addition to the number of wetlands that can have water, the carrying capacity will be influenced by the size of the continental breeding population of ducks, because that will influence the number that move into other areas as opposed to the prairie pothole region of the U.S. And also the conditions of the wetlands. In other words, if prairie Canada is really wet in a particular year, then they’ll attract a lot of breeding birds. Whereas, in a dry year, a lot of those birds might try and settle in the U.S. But generally, what I’m speaking about when I’m talking about carrying capacity is the capability of the landscape to attract breeding ducks to the wetlands there.
ES: Why did you chose to study ducks in particular?
Reynolds: One of the reasons that we focus on waterfowl is that we have a lot of biological information a a result of surveys. And the reason for these surveys is to allow the Fish and Wildlife Service to set hunting regulations annually for waterfowl based on population characteristics. And so we have we have more information on waterfowl than we have for some of other birds. Our office here, the habit office, is working to develop additional surveys and monitoring programs for other birds. There are five or six important breeding shorebirds — marbled godwit, willets, wilson’s foul rope, american avocet, even piping plovers for that matter — that depend on wetlands in the prairie pothole region for their primary nesting and brood rearing. And, interestingly enough, all of those shorebirds that I mention also nest in the uplands similarly to ducks. And so a lot of the actions that take place in the land that influence waterfowl will also have a similar influence on these upland nesting shorebirds. And, in addition to that, there’s a host of other wetland species such as black crowned night herons, American bittern, a number of different rails and american coots, black terns, just a tremendous number of wetland bird species that are also impacted by what goes on in the landscape relative to the changes in the wetland and the upland community.
ES: What is this project called, when did it start, and when will it finish?
Reynolds: Well, our office doesn’t have a particular project. Basically what we do, we’re responsible for monitoring, evaluating and biological planning for all the partners of the prairie pothole joint venture, and the National Wildlife Refuge system in the prairie pothole system. And so we’re we’re constantly starting new monitoring programs or cooperating with other organizations like Ducks Unlimited, the USGS Biological Resources Division, or universities to collect information and try and develop a better understanding of the relationship of migratory birds primarily, and the characteristics of the landscape. And so if we can understand those characteristics of the landscape and the biological components of the species, how they interact, then we can do a fairly good job of simulating the impact of the populations due to changes in the landscape.
ES: What’s a typical day in the field like?
Reynolds: Certainly, most of our fieldwork is in the spring and summer, depending on what type of survey we might be involved in. The people that work for me in the habit office will go to the field early and usually start surveying waterfowl populations or shorebirds. We have a breeding shorebird study that we started 2 years ago. And basically , the habit staff would be in the field from early morning till mid to late afternoon. We’re going to preselected, random wetlands, or transects, and collecting biological information on the occurrence of migratory birds, and in some cases, nest success. We have various methods for locating upland nest of waterfowl and shorebirds. So we find those nest and collect certain types of data on the nest, in regards to the number of eggs in the nest and the incubation stage as well as the habitat the nest is in and the locations. We might collect a position, a coordinate using a GPS so that we can then use that information in a geographic information system type of analysis. Because we have land cover information for all these areas that we study, as well as the wetland database, and it’s all in a digital format. So basically, if we know the location of a nest using a GPS, we can characterize the habitat around that. back in the lab. And so that would be a typical scenario for someone in the habit staff in collecting that type of information about migratory birds.
ES: In the course of the duck study, what was something that really surprised you?
Reynolds: Well, I guess one of the things that is really kind of interesting is that when we were evaluating CRP in regards to nest success for breeding ducks, we found that the CRP cover exhibited higher nest success than almost any other cover type that was out there. Of course that wouldn’t surprise somebody relative to cropland, but we also found that CRP had higher nest success than almost any of the other cover types as well. Another thing that kind of stuck out was that in certain fields of CRP, we get extremely high densities of duck nests, in the neighborhood of two or three nests per acre. That’s very high for unprotected cover. And it wasn’t all of the fields that had that high a nest density. It was only certain fields. And sometimes, you could look at a field and you couldn’t tell the difference between one field and one next to it. Whereas one field might have one nest for 20 acres, the other field right next to it would have two or three nests per acre. And what we generally kind of concluded from that, or at least hypothesized, is that the females seem to be more successful in areas where they have these real high concentrations. And I think what’s happening is sometimes they have a way of communicating or maybe observing other ducks that are nesting in a successful situation, so they tend to move into those areas where it appears that other ducks are having success in nesting. And so the distribution of the nest and the cover is not random. In some cases, not always, but in some cases, under certain conditions they seem to be selecting for the successful cover, so to speak. So that was surprising. That was something that we really didn’t expect to find, and it also stood out quite a bit in terms of the other data. We ended up calling them “hot spots.”
ES: Could we come back to the Conservation Reserve Program and talk about that a little more?
Reynolds: First of all, back before humans settled this area, this landscape was predominantly grassland dominated, grassland and small wetland. Now, in North Dakota, 75 to 80%, and similarly, probably a little less in South Dakota, of the grass has since then been plowed up and put into crop production. In areas like Minnesota and Iowa, greater than 90% of the grasslands are being converted into crop production. The Conservation Reserve Program was first initiated as part of the 1985 Farm Bill. And basically what it did was, land owners could enroll cropland into the program and for a ten-year period, they would convert that cropland to perennial cover, and in this area, mostly a grass-legume mix as part that would remain idle. It couldn’t be used for grazing or haying except under agriculture emergency conditions such as an extreme drought or something of that nature. So the land was intended to be idle. And then in exchange for that, land owner gets a payment, annually, per acre, that’s roughly equivalent to the cash rent value of the land, in other words, the same amount that they would get if they rented it to a neighbor for crop production, plus a small additional fee for management or maintenance of the cover. There’s certain things that have to be done such as weed control and that sort of thing. And basically, during the course of that ten year period, that land had to be left idle. Now that’s interesting and important, because if you go back far enough in history, you don’t have to go too far, but a couple of hundred years, 150 years ago, the land was certainly grazed periodically by herbivores in North America, but it was not grazed season long, such as the way the cattle grazing occurs And so there were areas where the land had been grazed for a particular area, and there were other areas where the grass was idle for several years. Well, now the landscape prior to CRP is either in cropland, or it’s in grassland that’s used primarily for grazing. And as a result, the grass structure is very short. There’s very little cover on the land area that’s grazed, because the cattle keep it grazed down. And so when the CRP came along, it provided a component of t cover that had been missing for many years, and that was an undisturbed component of grass. And some bird species responded to that cover type in a really dramatic way. And those species were primarily the birds that preferred dense, tall, undisturbed cover for nesting, such as upland nesting ducks, some species of songbirds, grasshopper sparrows, lark buntings, bobalinks. And some of these grassland bird species such as grasshopper sparrows and lark buntings, for instance as an example in North Dakota, their populations had been declining for around 20 years or so. And when CRP came along, their populations took a real sharp increase. And so CRP, you can’t draw a conclusive cause and effect relationship, but certainly the circumstantial evidence indicate that CRP had a positive influence on the population of those two species as well as some other species that used the cover of those as well. But the most dramatic change occurred with grasshopper sparrows and lark buntings. And we saw a tremendous response to this cover by upland nesting ducks. So, that’s pretty much the program in a nutshell. The contracts were basically entered into with the landowners from the 1985 Farm Bill, primarily from 1986 to about 1992. After that there were very little CRP contracts that were entered into to. Most of the acres nationally had been accepted into the program as a result of the cap. There was a 36.4 million acre cap. And so most of those acres had been contracted, so there wasn’t a lot available after 1992. Then when the Farm Bill was reauthorized in 1996, CRP was again part of the Farm Bill, but most of the contracts were expired by 1996-97, and so as a large number of contracts were expiring, new contracts were being taken into the program in addition to some of the older contracts were renewed. They had to bid them back in based on what’s called and Environmental Benefit Index. So now we have, basically, two back-to-back CRP programs in the Farm Bill that have placed, for instance, 3 million acres in North Dakota of CRP on the land. In other words, 3 million acres of cropland in North Dakota has been converted to undisturbed grass since about 1986. So going on about 15-16 years of this program, with an additional 4 or 5 to go. So the program’s been extremely important. In the prairie pothole region in general, I’d say that the number of acres is somewhere in the neighborhood of 7 to 8 million acres that have been converted. It’s really a tremendous number of acres that have been put into this program and benefitted the wildlife of this area, not just the migratory birds, but also resident wildlife and sharp tailed grouse, which are a native grouse species to the mixed grass prairie. And a number of upland nesting songbirds as well.
ES: What are some of the critics saying about the CRP?
Reynolds: The CRP is a very popular program with the land owners. And that’s one of the reason’s why I think it’s so interesting. It really is a win-win. It’s voluntary. The land owners sign up for it, they’re not forced into it by any means. So they they basically go into the Farm Service Administrative Office and say, “hey, I have some land that I’d like to try to enroll in CRP.” Now there’s a number of reasons why some land didn’t get reenrolled. Some land owners decided that after 10 years of contract, that maybe they’d like to crop some of that land again. But I think more often than not, many of the land owners bid the land in as CRP but it was not accepted. Between the 1985 Farm Bill and the 1996 Farm Bill, there were changes made in basically the rules, the eligibility, the scoring for the CRP contracts. Basically what they call an Environmental Benefit Index. And USDA in an attempt to try and increase the environmental benefit that they got out from this CRP program developed this index so that they could maximize the benefits from the the program from an environmental standpoint. So they were looking at a number of things, not just wildlife, but water quality issues, soil conservation, clean air, a whole host of issues relative to conservation, not just wildlife. From a wildlife standpoint they were also looking at migratory birds in addition to resident wildlife. And so when they basically developed the Environmental Benefit Index, some lands that had been in CRP no longer scored very high, so those lands were not reauthorized or accepted again in the new program. But other lands that had not been in the program previously, those land owners were interested in bidding that land in, and they scored high enough to get accepted. So really, what we saw, especially in North Dakota, as an example, and Montana I think as well, is an increase in CRP in the 1996 Farm Bill as compared to the 1985 Farm Bill. There’s actually still a tremendous interest by land owners. We actually ended up with more CRP in North Dakota and Montana. South Dakota didn’t come out quite as well. But part of that has to do with the individual county agents and how they scored the bids. It’s not always consistent from one county to the other. If you understand how the farm program is administered, you wouldn’t be surprised at that. It’s very complicated, and sometimes they don’t have a whole lot of time to try and deal with all of the issues and say try and get the maximum benefit, the maximum point score for a particular land owner. So there’s quite a bit of changes. But, generally speaking, I think that the program is just as popular, if not more popular, than it ever was. There are some lands that, as a result of the most recent farm bill, which still include CRP that was signed last summer. There are somewhat greater incentives for crop production because of additional crops that the farm program allows for a subsidy, or insurance, or whatever. And as a result of that, some crops that were not being grown, say in the Northern Plains, previously, are now being planted and there are some opportunities for profit in some of these newer crop types. And some land owners, instead of enrolling in CRP are choosing to continue to crop their land, or in some cases, take land that was previously in CRP and turn it back into crop land. But I think in general, that the CRP program is still very popular.
ES: Is there anything else that you’d like to tell the listeners of Earth and Sky today?
Reynolds: It seems like in general, the landscape issues in this area are primarily the conversion of grass and wetland into cropland. Our office is trying to help conservation groups from any area whether they’re private, state, or federal, to understand the implications of changes in the landscape so that wise decisions can be made for the future, because I believe that somewhere down the road, the American people are going to look back, and they’re going to judge our generation, and our group by what we left them in terms of wildlife resources and sound environmental policies.
