Northern Prairie Wildlife Research Center
Without proper consideration of background, perspective, and scope, the task of evaluating the impacts of wildlife management practices on nongame birds would be unproductive. The following discussion provides some insight into these critically important aspects and also introduces some concepts that are crucial to the evaluation process.
North Dakota lies at the center of the North American continent. Since the last Ice Age it has been a land of open grassland with subtle changes in topography, numerous wetlands, and very little native woodlands. These characteristics, along with fertile soils and productive range lands, made it a prime area for conversion to agricultural production.
The face of North Dakota has changed since the days when bison and fire determined the condition of the prairie. Today the state is among the leaders in production of small grains, sunflowers, potatoes, and livestock. With this conversion to agriculture came significant changes to the landscape. There is precious little remaining of the native habitats that once occurred in the state. Those areas of native vegetation that still exist are fragmented and are often in a degraded condition.
In addition to the changes in the native landscape, it is important to note the ownership of the land. Over 95 percent of the state is privately owned. Therefore any actions to preserve, protect, or enhance what habitat remains, both native and non-native, must involve the cooperation of private landowners, many of whom make their living by using the land.
Prior to our evaluations we determined that it was absolutely necessary to recognize, accept, and consider these factors. By not incorporating the current situation, we would simply be conducting an exercise in wishful thinking. The landscape of North Dakota is not going to change significantly in the foreseeable future. It is not going to revert to a fully functioning native prairie ecosystem.
North Dakota will remain an agricultural state. Crops, livestock, and privately owned land are what it will be. There will be some remnants of native woodlands, grasslands, and wetlands in both public and private ownership. But they will not be functional ecosystems in the classic sense. It is our challenge, as wildlife and natural resource managers, to conserve, protect, and enhance these bits and pieces of habitats to the best of our ability.
The goal of this effort is relatively simple. We intend to evaluate the effects of certain wildlife management practices on nongame bird species in North Dakota. How we do this evaluation is not so simple.
First it must be clearly understood that the management practices we are reviewing are commonly used in North Dakota by the US Fish and Wildlife Service and ND Game and Fish Department, as well as other agencies and private conservation organizations. The primary purpose for these practices is usually to enhance and develop habitat for waterfowl and other ground nesting game bird species such as ring-necked pheasants, sharp-tailed grouse, and prairie chickens, as well as other popular game species such as white-tailed deer and wild turkeys.
A significant portion of the funds available for wildlife habitat enhancement, development, and protection are derived from hunters and anglers who purchase state licenses, permits, federal duck stamps, and pay federal excise taxes on sporting goods. This fact often dictates the priorities adopted by state and federal wildlife agency policy makers. Cooperation between specific user groups, such as Ducks Unlimited, Pheasants Forever, and local rod and gun clubs also enter into determining programmatic decisions and focus.
The management practices to be evaluated strive for improved habitat condition. The underlying concept of these practices is that the key to healthy wildlife populations, whether they be game or nongame, is habitat. The sought-after habitat condition is that which is complementary with the prairie environment.
Without question there are some important peripheral species, such as the cerulean warbler, that may occasionally be found in North Dakota. However, these individuals' contribution to the continent- wide population is minimal. Regional endemics, such as Baird's sparrow, which breed in good numbers in North Dakota, are more of a priority for natural resource managers in the grasslands. Therefore the perspective of this report and its evaluations are founded on what's best for those grassland and wetland species that naturally occur in North Dakota and for which the state provides important habitat.
Along with understanding the landscape, its current condition, and the evaluations' perspectives, it is also critically important to consider the scope of the management practice in question. For instance, when we evaluate the restoration of a two- to five-acre wetland in a tame grass or crop field, we must recognize that there may be some negative effects.
It could be argued that this wetland restoration would result in the loss of two to five acres of nesting habitat for grasshopper sparrows and clay-colored sparrows. However, there could be 155-158 acres of similar habitat still available in that same field. While being somewhat detrimental to these two species, numerous birds might benefit by having the drained wetland restored. In this case the positive effects for several dozen species clearly outweigh the minimal negative impacts to a few.
A similar example would be the control of cattails. Reduction of cattails is desirable in some areas where cattails have taken over nearly all or even an entire wetland basin. The object of the management practice is to create a hemi-marsh with 50 percent open water and 50 percent cattails. This practice, in effect, creates edge habitat which is desirable to many species, as well as open- water habitat that is needed by still other species.
Once again, the key to the use of this management practice lies in scope. Is this the only cattail dominated marsh in the area? If it is, don't do cattail control. If there are significant areas of dense cattail stands in the adjacent area, then the management practice will have little effect on the overall population of those species that use cattail stands and the species that use open water and edge habitats will see improvement.
In the case of unique, rare, and specialized habitats, scope is probably even more important. In these instances, even the loss of one or two seemingly small, insignificant areas may be critical. Type II wetlands are a commonly used example of a rare habitat that has been impacted by traditional waterfowl management practices. These areas are sometimes inundated to create open-water wetland habitats, which are recognized as being beneficial for ducks and nesting Canada geese. However, the impacts to a host of habitat specific nongame bird species are potentially devastating.
Habitat areas that provide for specialized assemblages of bird species such as these should be avoided. In the overall scope of available opportunities for open-water wetland creation and enhancement, type II wetlands are minimal. Their avoidance will not result in less wetland creation or enhancement, but simply focus management in habitat areas that are more common and less susceptible to significant negative impacts.
These examples may seem to be over-simplifications of the evaluation process, however they illustrate the thought process that should go into the consideration of scope. Obviously, there are a lot of other factors to consider, but the process should basically be the same. The bottom line when considering scope is the need to strive for a natural mosaic of habitat and diversity in the regional landscape.