Why You Should Care About Wild Duck Genetics: Dr. John Coluccy

Growing up camping, cane pole fishing, and hunting Canada geese with his father, Dr. Coluccy naturally gravitated towards hands-on education in the outdoors. His early experiences managing a local pheasant put-and-take and chasing grouse and woodcock sparked an initial interest in upland birds, but annual fall trips to hunt Canada geese around the Horicon Marsh — a historic staging area for Mississippi Valley Population Canada geese — ingrained in Dr. Coluccy a deep-rooted respect for and unshakeable interest in waterfowl.

“The sound of the morning eruption of geese from the marsh  lingered in my ears following each hunt. At night, it’s almost like you went to a Ted Nugent or a heavy metal concert and your ears are ringing after the show. I quickly grew very fond of these birds, so I jumped at the chance to study them down in central Missouri as part of a graduate program.”

Before his graduate degree program, Dr. Coluccy gained experience working on a variety of wildlife ecology projects. These experiences culminated in a position as a waterfowl technician working with Canada geese on a lead poisoning study. His time as a waterfowl tech took him up to the Delta Waterfowl Research Station in Delta Beach, Manitoba where he worked with canvasbacks and captive diving ducks, two projects which cemented his confidence that waterfowl would be the focus of his education and career. He also ventured to Louisiana to work with canvasbacks in the winters where, never having duck hunted previously, he discovered his love for waterfowling. 

Soon thereafter, Dr. Coluccy began working towards two graduate degrees at the University of Missouri. Upon completing his PhD in 2001, he began working for Ducks Unlimited with a focus on science and securing the future of waterfowl populations across North America.

With his cumulative experience from hands-on work and graduate degree programs, Dr. Coluccy — now a part of the national science-based conservation organization that is Ducks Unlimited — put his efforts towards researching waterfowl on a larger scale. While researching population dynamics for resident Canada geese in Missouri, Dr. Coluccy worked extensively with demographic modeling, applying simulations to search for state-wide solutions for population management. He has built upon the work of Ronald Drobney, his advisor at the University of Missouri, and has done extensive research on the mallard populations that call North America home. 

“When we — the general public — think about mallards, we’re probably thinking a mallard is a mallard. That’s not the case; we have a continental population of North American mallards that is distinct as a population, demographically separate, geographically and genetically isolated from European mallards. When we survey that continental population of North American mallards, we separate them into western, midcontinent, and eastern mallards. They can be thought of as subpopulations of the broader continental mallard population that are unique in regards to where they breed.” 

The largest of these three subpopulations are midcontinent mallards. These are the mallards found in the Prairie Pothole Region which, as Dr. Coluccy puts it, is “production area #1” for mallards. He emphasizes that, though some of these subpopulations are smaller, it is important to pay attention to each. By tracking each of these populations, hunters and scientists are able to look at trends in migration patterns and population numbers, helping to identify troubling trends, inform harvest regulations and give waterfowlers a sense of what they may see in the coming waterfowl season. Separating these mallards by location allows for more intensive and specific collecting and monitoring of data, enabling scientists to look past a year of decline in order to see the larger trends at play.

“If we have a year of a down population, there’s understandably some concern. When the low duck population numbers come out in the Ducks Unlimited Magazine or on social media, waterfowlers get all riled up. But, as waterfowl scientists, we're more interested in long-term trends— five-year, ten-year, twenty-year declines. That’s when you start seeing those signals that something is wrong, and that’s what triggers research into trying to figure out why observed declines are happening.” 

Dr. Coluccy explains that both eastern mallards and Great Lakes mallards have seen a long-term decline in numbers. These trends cause concern among scientists about habitat conditions and land use. Mallards need an abundance of wetlands, food sources and grassland to support successful reproduction to sustain the population. Declines in population numbers prompt scientists like Dr. Coluccy to question what’s driving the decline and where their habitat needs are not being met and evaluate what can be done to improve the situation. 

Dr. Coluccy explains that the advent of GPS/GSM tracking devices has made conducting studies across the life cycle of waterfowl more possible than ever. This boon of research has shed light on migration corridors, connectivity between and habitat use during breeding, migration and wintering areas, breeding population dynamics, and two top-of-mind issues for waterfowl scientists: land use and duck genetics.

When it comes time to migrate, each mallard subpopulation has its own flight paths and range it has been observed to cover. These migrations are driven by seasonal changes, associated with storm fronts, temperature, wind, and the amount of snow and ice cover.

“For breeding waterfowl, there is absolutely no question that prairie potholes — shallow, seasonal, ephemeral wetlands that are wet for a short period of time in spring — along with semi-permanent and permanent wetlands are tremendously important. Typically the number of wetlands in an area dictates the number of breeding pairs that settle. . These small wetlands, oftentimes, are the first ones that are available in spring and they're chock full of invertebrates, a critical source of protein and minerals for egg formation. Wetlands are where courtship happens and where males defend their prize, the hen. You need high densities of wetlands to support robust breeding populations, so there's a really strong correlation between the May waterfowl population survey estimates and May pond counts. When it's wet, and there are a lot of prairie potholes, you have high breeding pair densities.”

The land is changing, and the ducks are telling us. The long-term declines of eastern and Great Lakes mallards coincide with significant changes those regions have seen in terms of land use, explains Dr. Coluccy.

“A lot of that land is spent due to agricultural production. We have a lot of people in the US, Canada, and around the world to feed, so a lot of waterfowl habitat has fallen to the plow. The Prairie Pothole Region in Iowa and Minnesota used to be among the most dense with wetlands at one time, but it's virtually all been drained, and all the grass has gone with it. We lost wetlands in the Great Lakes and northeast too. Small pothole wetlands are usually the first ones to be drained. They're a lot easier to get rid of, but they're also the most important for breeding waterfowl. They’re really what drive our populations.”

There is a balance between achieving ideal conditions to ensure a thriving duck population and the necessity of setting aside land for agricultural production in the United States. Farmers are some of the largest private landowners in the country, and within these lands are most of the remaining waterfowl habitats the US has to offer. Ducks Unlimited seeks to work with farmers, pushing mutually beneficial incentive programs that promote setting aside marginal areas for waterfowl and other wildlife.

While drought and land use change certainly has contributed to the downward trends in mallards, it’s not the only factor at play. To paint a full picture of this population decline, we have to look back at the history of mallard population management in the United States. 

In the 1930s duck populations were in a bad spot, when Dust Bowl conditions resulted in all-time population lows. This prompted the formation of Ducks Unlimited, an organization dedicated to securing the future of the continent’s waterfowl. Declining mallard populations prompted concerned hunters and groups and resource agencies to raise and release mallards, in hopes of restoring the wild mallard population to what it once was.

These well-intentioned efforts unfortunately created a problem that endures to this day. The mallards that were raised and released were genetically different from those in the wild. These birds would come to be called game-farm mallards and are closer genetically to European mallards. Today, they pose a threat to wild mallards, as cross-breeding threatens their genetic integrity. 

Scientists hypothesize that inferior genetics of hybrid mallards may manifest itself in less dense lamellae,  the part of a duck’s bill meant to act as a filter to forage for seeds. The wider the distance between lamellae, the more trouble a mallard has sifting small energy-dense seeds from wetland habitats. As a result, these hybrids may be less efficient foraging and meeting daily energy needs, which could affect habitat use, migration, and breeding success. Results from a recent study in the Great Lakes suggest hybrids move less daily and are less prone to migrate than wild mallards. Dr. Coluccy believes that these less-suited traits could weed themselves out over time, but the widespread continued release of game farm mallards may make that impossible. 

Waterfowl hunters feel the effects of duck population declines on a personal level. Each year, lower populations can result in fewer ducks seen on a morning in the blind. For Dr. Coluccy, understanding the trends in mallard populations represents an opportunity for broader engagement, for hunters and scientists alike to take part in learning about and managing our waterfowl populations.

“This is an opportunity to engage a broader audience with what we're doing and some of the science. Not only does it make people aware, but it keeps them passionate when you engage with these efforts. We all have a role to play when it comes to preserving waterfowl populations for future generations: scientists and hunters alike.”

To ensure that future duck hunters are able to enjoy the sport, it’s crucial that today’s hunters and outdoor enthusiasts take the time to learn about ongoing efforts to manage and conserve our waterfowl populations. To learn more about Dr. Coluccy’s work and waterfowl management at large, Ducks Unlimited is a great jumping-off point. If you’re new to duck hunting, start your adventure with AnyCreek. Check out our Outdoor Academy for more information on the history of duck hunting, and book with one of our professional duck hunting guides to experience the thrill of the sport that inspires individuals like Dr. Coluccy to devote a career to conserving our waterfowl populations.