Mid-continent populations of light geese (lesser snow geese [Chen caerulescens] and Ross's geese [C. rossi]) have increased considerably over the last thirty years, with greater annual survival and subsequent overpopulation of light geese resulting in long term damage to some arctic breeding areas. In an effort to reduce mid-continent populations of light geese, the Light Goose Conservation Order (LGCO) was initiated in 1999 with the goal of reducing mid-continent light goose populations by 50 percent from those observed in the late 1990s. The LGCO allows harvest of light geese after March 10th, as well as use of electronic calls, unplugged shotguns, and extended shooting hours. Due to concern for LGCO activities to negatively impact non-target waterfowl species during spring migration, LGCO regulations in the Rainwater Basin (RWB) region of Nebraska restricted hunting to four days a week and closed 16 public wetlands to LGCO activities (off-limits to hunting) beginning in 2004. In 2011, the Missouri Cooperative Fish and Wildlife Research Unit, in collaboration with Nebraska Game and Parks Commission, initiated a research project to examine the effects of LGCO regulations on the distribution and behavior on non-target waterfowl using the RWB region as a migration stopover site.

Other studies have shown local redistribution of waterfowl in relation to hunting disturbance.  Previous research on LGCO activities in the RWB reported a reduction in dabbling duck numbers on wetlands open to spring hunting of light geese during years with low wetland availability. Local redistribution caused by hunting disturbance has the potential to reduce lipid acquisition of dabbling ducks during spring migration either by causing birds to use lower quality habitat (less food availability) or increasing movements (increased energy use).  Waterfowl migrating north without adequate lipid (energy) reserves may reduce nesting efforts once they reach their nesting grounds. Providing wetlands free from hunting disturbance during the LGCO is a potentially important management strategy in the RWB.

To evaluate the effects of LGCO on non-target waterfowl species in the RWB, researchers with the Missouri Cooperative Fish and Wildlife Research Unit quantified waterfowl abundance in wetlands open to hunting and those off limits to hunting under the LGCO during springs of 2011 and 2012. A total of 22 public wetlands (13 open to hunting and nine off limits to hunting) were used as study sites over the two-year project. All observed dabbling ducks and geese were recorded during waterfowl surveys conducted at each study site 3-4 times/week from early February to mid-April. Observers also recorded the presence of any hunting parties at the study wetland during waterfowl surveys.

A total of 541 waterfowl surveys on wetlands open and off limits to hunting were conducted.  Seventy hunting parties were observed on wetlands open to LGCO hunting over both years combined, confirming that areas open to hunting were in fact hunted. These data are being used to examine dabbling duck densities on hunted wetlands relative to those on wetlands off limits to hunting. In addition, these data will determine if "resting" an open area from hunting (no hunting on certain days) impacts dabbling duck densities.

Data from this study will help determine impacts of a LGCO season with more allotted hunting days/week combined with the current network of wetlands closed to LGCO hunting, as well as the distribution of non-target waterfowl species using the region for spring staging. An increase in days open to hunting may also increase hunter participation and ultimately aid in the reduction of mid-continent light goose populations. Assessing and understanding potential effects of LGCO regulation changes on waterfowl using the RWB during spring migration will allow waterfowl biologists to make regulatory decisions within an adaptive management framework.

Each month, the ONB features articles from Cooperative Fish and Wildlife Research Units across the country. Working with key cooperators, including WMI, Units are leading exciting, new wildlife research projects that we believe our readers will appreciate reading about.