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RESEARCH AND EDUCATION 2021 STATUS UPDATE Studying the seasonal and annual “movement ecology of ring-necked ducks in the southern Delta furthers the research Atlantic Flyway helped that keeps waterfowl grow my passion for research and pushed ™ populations strong me to continue my Using the latest technology, researchers education to obtain answer tough questions about duck a Ph.D. Tori Mezebish production and wetland conservation UNIVERSITY OF today and in the future RHODE ISLAND 2025 PH.D. BIOLOGICAL” AND ENVIRONMENTAL SCIENCES Delta Waterfowl believes that water- It’s a philosophy Delta has followed fowl management decisions should since Albert Hochbaum began his always be based on sound science. work as the organization’s first science 2021 research program. The summaries director in 1938 at the Delta Marsh. that follow provide a snapshot of each Delta has continually focused research project, and more detailed information is DELTA HAS TRAINED MORE on ducks and duck hunting issues in available. As always, feel free to contact THAN 600 MASTER’S AND North America. This strategy allows me to discuss any of Delta’s research. DOCTORAL STUDENTS, The Duck Hunters Organization to INCLUDING SOME OF TODAY’S study important, long-term issues, as Dr. Chris Nicolai FOREMOST WATERFOWL well as new concerns impacting ducks Waterfowl Scientist BIOLOGISTS and duck hunters. (775) 830-1632 [email protected] THE DUCK HUNTERS ORGANIZATION This special report highlights our 1 Canvasback Nest Success cameras, since this approach has proven “hot spots” (i.e., grass-only sites) would Evaluating Predator Management for over-water nesting ducks far superior to field assistants doing allow waterfowl managers needed ground counts. Rohrer will be finishing flexibility in both the size and loca- TRENT ROHRER, M.S. STUDENT, AND DR. JOSH STAFFORD, his M.S. work this year. tion of Predator Management sites. SOUTH DAKOTA STATE UNIVERSITY This project will take place in North Hot Spot Trapping to Dakota and help inform whether “hot Delta continues to seek effective and Improve Dabbler Production spot” trapping can help increase duck Evaluating dabbler nest success efficient application of Predator Man- with a new trapping technique production in the best quality habitats. agement techniques to improve nest To estimate how many ducks are MATT DAVIS, M.S. STUDENT, AND success for over-water nesting ducks DR. CHRISTOPHER MALCOM, using the different treatment blocks, such as canvasbacks, redheads and BRANDON UNIVERSITY we are using a variety of methods to ring-necked ducks in the parkland estimate how many nests are missed habitat of Canada. Delta is exploring whether focusing using a single pass chain drag. Efforts Rohrer has spent the past two years Predator Management on highly pro- to use GPS to map ATV tracks and exploring whether trapping in the fall, ductive patches of grassland habitats nests will allow the use of distance in addition to the spring, is a more could more efficiently boost produc- sampling methods. We are also effective way to reduce key mammalian tion of dabblers such as mallards, dragging a sample of nesting cover nest predators, especially raccoons. pintails and gadwalls. This project a second time within 20 minutes to We discovered fall trapping did little is vastly different from past nesting/ determine how many nests are missed to improve our take of raccoons – predator removal projects in that we on a single pass. public enemy No. 1 of canvasbacks. are interested in assessing how many However, our spring trapping in 2020 ducks are attempting to nest, rather Raccoon Satellite Telemetry Studying movements and habitat use showed some very positive signs, than simply measuring nest success. of raccoons to improve effectiveness so we intensified that effort for the Predator trapping has typically of Predator Management second field season. That includes focused on the full area of a town- DR. CHARLOTTE MILLING, trapping out in wetland edges where ship-sized block. Recent Delta research POST-DOCTORAL RESEARCHER, DR. STANLEY GEHRT AND our satellite tracking of coons showed projects have identified “hot spot” MR. SHANE MCKENZIE, MAX these introduced predators spend an trapping as a potentially more effective MCGRAW WILDLIFE FOUNDATION inordinate amount of their time. We approach to removing predators and will be counting broods using drones a more efficient use of management In 2018 and 2019, we fitted 29 rac- equipped with thermal and visual dollars. Focusing trapping efforts on coons with GPS transmitting collars on Delta’s canvasback study block in Manitoba. The transmitters collected ™ incredible amounts of location data on each raccoon’s daily movements. We discovered that raccoons spent a large percentage of time in wetland edges. Due to Covid-19, we were unable to track any raccoons in 2020. However, we are planning to collar 15 raccoons to track their movements in breeding duck habitat. The goal is to better understand raccoon habits so we can set traps in their preferred locations, thereby more effectively reducing these top predators of diving-duck nests. We will also use stable isotopes to evaluate the role of duck eggs in the diet of raccoons. Ultimately, the goal is to learn more about raccoons so we can manage these non-native predators and increase production of canvasbacks, redheads, ring-necked ducks and other THE DUCK HUNTERS ORGANIZATION over-water nesting ducks. 2 This experience has greatly helped my career. I’ve had the “ opportunity to meet many researchers, hunters, and landowners and share with them why we’re doing this research. After graduation, I’ll be starting a position as a research scientist, due in large part to the experience I gained doing research for my master’s degree with Delta Waterfowl. Catrina Terry LOUISIANA STATE UNIVERSITY 2021 MASTER OF SCIENCE ” ™ THE DUCK HUNTERS ORGANIZATION 3 harvest — the only diver consistently in the top 10 in all four flyways. Ringnecks are doing well, and we hope to understand why they have been so successful at increasing in numbers. In addition, this research has immediate value to waterfowl managers in the Atlantic Flyway under the recently implemented multi-stock harvest regulation-setting method. Importantly, our study suggests that ring-necked ducks that winter in the southeast are not nesting in the eastern survey area, but farther west. Eastern Mallard banding and isotopes Using isotopes to determine whether mallards are moving between the US and Canada during banding operations KAYLA HARVEY, M.S. STUDENT, AND DR. MIKE SCHUMMER, STATE UNIVERSITY OF NEW YORK COLLEGE OF ENVIRONMENTAL SCIENCE AND FORESTRY Counting Broods Ring-necked Duck Tracking Implanting satellite transmitters to Using Drones Mallards in the Atlantic flyway have Evaluating brood use of wetlands in monitor movements and habitat use agricultural landscapes declined by 40 percent in recent years, DR. MITCH WEEGMAN, and reasons for this decline are not well CATRINA TERRY, M.S. STUDENT, AND UNIVERSITY OF MISSOURI DR. KEVIN RINGELMAN, LOUISIANA understood. Banding data, specifically STATE UNIVERSITY pre-hunting season banding, is an After three successful field seasons important tool used to monitor mal- In 2019, we surveyed 242 PPR wet- marking ring-necked ducks in 2018, lard and other waterfowl populations. ™ lands using a combination of cam- 2019 and 2020, Delta implanted an Production and survival estimates for era-equipped drones and wetland additional 31 ringnecks with satellite Atlantic flyway mallards, informed sampling and found 240 broods. In transmitters in Maryland during the by banding data, have not changed 2020, 92 wetlands were sampled to fourth and final field season of the significantly during the decline, sug- find 88 broods. project in February 2021. gesting a possible bias in these data. Using a special drone equipped The goals are to monitor migration An important assumption used for with a thermal-imaging camera and paths, discover breeding areas, and these estimates is that birds do not move a regular camera, researchers survey understand habitat use and movements between survey units. Recent research selected wetlands in agricultural land- suggests the potential for migration of scapes for brood use. The goal is to mallards during the banding period. better understand brood use in order DELTA WATERFOWL’S This project aims to use stable isotope to conserve the most important habitat RESEARCH AND EDUCATION analysis to determine whether mallards for breeding ducks. This research will PROGRAM HAS RESULTED are moving during the banding peri- evaluate the quality of wetlands as brood IN MORE THAN 950 PEER- od. Feather samples from pre-season water by examining usage by ducks, REVIEWED STUDIES banded birds throughout the Atlantic as well as determining invertebrate flyway will be collected for analysis abundance, vegetation structure and of the deuterium isotope to obtain insecticide concentration. during the ringneck’s annual cycle. Little general molt or natal origins. These Terry has finished this field work is known about ring-necked ducks, will then be compared to banding and expects to complete her M.S. which is surprising because they are the locations to assess movement during THE DUCK HUNTERS ORGANIZATION this year. most important diving duck in hunter the banding period. 4 ™ While working as a Delta researcher, I have been able to connect and network with a wide variety of people in the hunting, research, and agricultural communities. I learned “that conservation issues are complex and challenging, nothing happens overnight, and working hard to connect with people helps to build the necessary relationships that push conservation forward. Michael Johnson, COLORADO STATE UNIVERSITY 2023 PH.D., FISHERIES, WILDLIFE AND CONSERVATION BIOLOGY ” THE DUCK HUNTERS ORGANIZATION 5 Lower Mississippi Working Wetlands influence does hunting harvest have Understanding farmers’ perceptions Flyway Dabbler Tracking on populations? Determining duck locations during of Delta’s Working Wetlands program By using new scientific approaches, hunting seasons and migration DR. CHERYL WACHENHEIM, NORTH DAKOTA STATE UNIVERSITY the team can more accurately answer DANIEL ODIN, M.S.