Delta Student Research Projects Span the Continent
From ALUS to human dimensions to predator management and moist-soil management, Delta’s crack team of researchers is examining an incredibly diverse list of topics
Pack an extra bag and snug up your seat belt—this year’s tour of student research projects takes us from one end of the continent to the other, revealing an unusually diverse roster of topics.
Let’s start our road trip out west with two students working in California. University of California-Davis student Brian Olsen is evaluating techniques for moist-soil management. Moist-soil units typically are impounded areas that dry in the spring or summer so that the soil allows seed-producing wetland plants like millets to get established.
When the plants are mature and the seasonal wetlands are re-flooded, ducks find an irresistible smorgasbord of food. Brian is evaluating different management strategies for moist- soil units.
Kevin Ringleman is another student working with Brian’s UC-Davis advisor, Dr. John Eadie. Kevin is taking a detailed look at the ecology of nest predation in an effort to understand how the behavior of nest predators affects the likelihood of predation in terms of space and time. Brian examines the nest site selection behavior of individual hens as well as the predation behavior of individual skunks. To monitor skunks, Kevin uses sophisticated GPS radio telemetry units that give exact locations at short intervals of time.
Traveling up the Pacific Flyway, our road trip takes us to Anne Mini’s doctoral project site in the Willamette Valley. Anne has the opportunity to examine how body size for a range of Canada and cackling geese influences their winter foraging ecology. This is of ecological interest as well as providing practical value for managing goose depredation issues. In this case, the geese are occasionally damaging sod farms with high intensity grazing.
Leap-frogging to central Alaska, we find one of Brandt Meixell’s study sites. Although Brandt is a Ph.D. student at University of Minnesota, he is looking at the pathogenicity of avian influenza viruses in wild birds from Alaska to the prairies.
Previous studies of pathogenicity have been conducted on captive birds where there is little environmental variation, and birds do not experience the stresses of scarce food, predators, or migration. Brandt will study various types of influenza on multiple species of ducks and look at body condition survival and reproduction.
Our next stop is the Utah State University campus, where we find Beth Ross behind a high-powered computer. Beth is analyzing scaup population models to find the most appropriate characterization of how this population changes.
Unfortunately, the trend in population change in the last two decades has been pretty consistently negative. The combination of declining numbers and very limited data other than the annual count information means that it is especially difficult to set scaup harvest rates so that we are confident that hunting isn’t contributing to the population decline. Beth is using the most advanced analytical techniques that wildlife biologists have at their disposal to try and produce a reliable growth model for scaup.
Continuing with scaup research we next visit the Centennial Valley of Montana where Kyle Cutting, a student at Montana State University, is conducting a more traditional field study. Kyle captured and radio-marked scaup at the start of the nesting season so he can document the impact of a female’s body condition on her probability of nesting and her seasonal productivity. There is some consensus among waterfowl biologists that scaup productivity has declined; detailed research like Kyle’s work will shed light on what is causing the lower production.
The parklands of central Saskatchewan are our next destination. Parklands, unlike prairie habitat, historically had a mix of both grassland-dominated habitats and a scattering of wooded areas. At some of John Dassow’s township-sized research plots the amount of bush habitat is impressive. While parkland habitats tend to be more predictably wet than grassland habitats, nest success on potentially productive sites is actually low because predation rates are high.
John’s study was d
esigned to test the efficacy of predator trapping in parkland habitats. First year results were impressive, with trapped sites showing a nearly five-fold increase in nest success over a control (no trapping) site.
The second year, John switched the treatment (predator reduction) and control (no trapping) sites, and found that all areas had poor nest success. John, who spends his winter months at Southern Illinois University, is back in Saskatchewan for a third field season looking for a clear answer about the efficacy of trapping.
Perhaps trapping predators will prove to be less effective in parkland habitat than grassland habitats, or perhaps the 2008 results were an effect of the particular landscape that limited the number of traps to less than half of what we use in North Dakota on a similar-sized block.
Traveling east to Manitoba we encounter another evaluation study of trapping in the parklands. This study is centered at Delta’s historic Minnedosa Field Station, where recent graduate students have reported abysmal predation rates and upland nest success of less than one percent. This study is planned as a long-term effort to assess nest success for both dabbling ducks and diving ducks (Minnedosa’s pothole country used to be some of the best canvasback breeding habitat in the world.)
In addition to assessing nest success, we will monitor pair numbers over several years to see if predator reduction in habitat that is underutilized by ducks will lead to an increase in the density of ducks over a series of years. Joe Lancaster is heading the team for this predator evaluation work.
A three-hour drive south of the Minnedosa site puts you squarely in the prairie grasslands of eastern North Dakota where Delta several students finishing a large-scale evaluation of predator management. Matt Pieron of Louisiana State University has directed a nest-searching effort over the last three years that located more than 8,500 nests on the trap and control blocks. As in prior studies, the nests on trapped blocks had significantly higher nest success than on non-trapped blocks – 64 percent on trapped block and 42 percent on non-trapped. However, the real focus of Matt’s dissertation work was to see if pair densities were higher on trapped blocks as a result of the elevated nest success.
Matt found that there was no significant increase in pair densities on trapped blocks, likely as a result of more than a decade of good production from the Dakota’s CRP rich landscapes. The thinking is that many areas of the Dakota’s are at or near carrying capacity and as such there is “no room at the inn” for other breeders on some sites,
Courtney Amundson is a student working on the same sites in collaboration with Matt, but Courtney’s work is focused on brood survival. Courtney, who works out of the University of Minnesota with Dr. Todd Arnold, spent a couple of years tracking mallard broods with radio telemetry and discovered that, unlike prior research in Saskatchewan, predator reduction in North Dakota was not increasing duckling survival.
Courtney’s estimates of brood survival on trap (19 percent survival) and non-trapped sites (22 percent survival) are among the lowest recorded for any mallard study. It must be noted that Courtney’s field work occurred during a period when wetland conditions were deteriorating with dry conditions and ducklings had scarce escape cover because of drought conditions.
Matt and Courtney’s findings strongly influenced Delta’s experimental predator program. This spring Delta, with much-appreciated technical assistance from the US Fish and Wildlife Service, selected all new trapping sites in North Dakota. Our new trapping sites are blocks of habitat where wetlands are abundant but cover is very scarce, so we expect low nest success.
Moreover, we are also attempting a supplemental trapping effort aimed specifically at mink, which are the most important cause of duckling predation. As you would expect from a research-based organization, these changes in the predator program call for a new phase of predator evaluation work. Starting this year, we will begin to assess the efficacy of trapping predators on this very different habitat configuration that occurs in parts of eastern North Dakota. With the declining CRP acreage, we fear that many more landscapes in the US may have low grass cover in the future and may be good candidates for intensive predator management, so the timing of this work is very appropriate.
Laura Beaudoin, a Ph.D. student from the University of Guelph in Ontario, is in her final field season working on the former predator treatment blocks. Recall that Matt Pieron found that pair numbers were not increasing over a series of years, even though nest success on trapped and non-trapped blocks was exceptionally high. So the question is what was happening to the young ducks that were being produced?
To answer this question Laura undertook some ground-breaking research to monitor the movements of young ducks as they achieve flight and become independent of mom. Much of Laura’s work was focused on fall survival and movements, which is a segment of the life-history that has been virtually ignored for 50 years.
Laura also uses some sophisticated radio packages that have an internal clock that turned off the radio in late November and didn’t turn on the radio again until March. This saved the battery so that Laura could determine whether the young females homes to North Dakota or dispersed. Laura’s first-year answer was remarkable: More than 60 percent of the radioed bird came back to near their marking site, but then they all soon dispersed to locations outside of North Dakota.
A final student working on the old trapped blocks is Tim Kimmel. Tim’s work builds on the research of Matt and Courtney using more than 1,000 banded hen mallards. These females have been monitored enough that they all have an individual nesting history. Tim’s research goal is to document the consistency of nesting parameters over years – so he monitors traits like exact nest location, the date of nesting, egg size, and number of eggs laid for females that we have repeatedly caught at their nest. Tim also relates all of these characters along with nest success to the age of the female.
After that long visit to North Dakota we travel south a few hundred miles to Nick Docken’s (South Dakota State University) study of predator management. Nick is evaluating trapping efficacy in South Dakota, but unlike prior predator work, this trapping effort is in prime ring-necked Pheasant habitat, so the goal is to assess duck and pheasant nest success. The duck results so far have mirrored most other predator studies with trapped site s having higher success (32 percent) than non-trapped sites (21 percent). However, pheasants have proved to be a lot harder to study because of the difficulty of finding nests. The preliminary finding suggest that nest success is pretty low, partially due to high nest abandonment, but that trapping substantially improves nest success.
Staying in the Central Flyway, our next stop takes us to New Mexico, where Dustin Taylor from Oklahoma State University is doing research on pintails wintering at the Bosque del Apache National Wildlife Refuge. This refuge is one of the few remaining spectacular wetlands in the Rio Grande river drainage and has immense concentrations of wintering ducks, geese and sandhill cranes. These birds help attract nearly 200,000 visitors to the refuge during the winter, which leads managers to question whether the human visitors are negatively impacting pintails. Dustin’s job is to answer that question using behavioral observations and by measuring stress hormones in captured pintails.
Now we skip east to the Mississippi Flyway for a stop in the Gulf Coast marshes of south-western Louisiana, where Bruce Davis from Louisiana State University is studying the non-migratory mottled ducks. The problem with year-round residents like mottled ducks is that Bruce rarely gets a break in his work schedule.
During the late summer he works with biologists from the Louisiana Department of Wildlife and Fisheries to capture flightless females during the annual wing molt. Some of these females are radio-marked and become the birds he tracks for the next year. Bruce’s study is focused on habitat use, but he is also collecting data on survival and movements. As you may recall, Louisiana was buffeted by two major hurricanes in 2008 (Gustav and Ike). Perhaps unsurprisingly, the mottled ducks simply moved inland during the tidal surges that came with the storms; they experienced no mortalities that Bruce could link to the storms.
Luke Laborde, another Ph.D. student from LSU, is working in the field of human dimensions and is focusing his research on duck hunters rather than on ducks. Specifically, Luke is looking at hunter participation and satisfaction and relating measures of hunter activity and perceptions of satisfaction with regulations, duck numbers, access issues, alternative demands on time and money, social climate, and a long list of other suspected deterrents to waterfowl hunting.
The impetus for this work is the decline in duck hunters and the concern that creates for the future of duck hunting, duck populations, and the protection of waterfowl habitat. Luke’s study will cover hunters ranging over the entire Mississippi Flyway.
Up at the north end of the flyway we would encounter Sarah Thompson from the University of Minnesota. Sarah is evaluating the impact of woody vegetation on duck nest success in western Minnesota. Sarah’s work entails searching for duck nests on many different Waterfowl Production Areas, some where woody vegetation was removed and others where woody vegetation remains. Sarah’s first-year results suggest that removal of woody vegetation to restore prairie areas does improve duck nest success.
As we move toward the Atlantic Flyway we encounter Rob Baden from the University of Western Ontario who is studying the winter ecology of canvasbacks and redheads wintering on Lake St. Clair and the Detroit and St. Clair Rivers in Michigan and Ontario. No, this isn’t traditional wintering area, but increasing numbers of birds that concentrated in this aquatic system during fall migration are selecting to stay all winter. Lake St. Clair is known for large bed of wild celery, but the birds that elect to spend the winter face risks of starvation during inclement weather. Rob is going to try and assess the benefits and the risk of short-stopping at this migratory area.
About 100 miles east of Rob’s study site is the Ontario demonstration site for ALUS – Alternative Land Use Services – in Norfolk County, which is just north of the legendary Long Point. Two students, Jessica Rosenburg and Paul Guerra from Guelph University, are undertaking research to help understand how to best implement this revolutionary habitat program.
Jessica is an economics policy student looking at the role of social capital and trust in delivering conservation programs on farmlands under ALUS. Her studies will investigate the capacity of communities to plan, manage and deliver conservation programs. She will identify factors that contribute to and detract from building social capital for conservation in rural communities.
Paul is also an economics policy student, but his project examines the economic concept of "club goods" where a number of interests in a specific set of goods combine their efforts to create a market for those goods, in the case of ALUS, the goods are ducks and other environmental goods such as clean air, clean water, habitat for species at risk and others. Paul will review all current policies and programs that may be integrated on the ground in support of ALUS in Norfolk County. The idea is to effectively combine all of the policies and potential resources available to ALUS in Norfolk County.
Our trip has taken us through some of the most important breeding, migration and winter habitat in North America. We encourage students to focus on important research questions, and that means we have to go to where the most important habitats are located