Date of Award

Spring 2001

Document Type


Degree Name

Master of Science (MS)


Biological Sciences



Committee Director

Robert K. Rose

Committee Member

Mark J. Butler

Committee Member

Alan H. Savitzky

Call Number for Print

Special Collections LD4331.B46 P43


Disturbance of wintering and migrating birds by human activities can cause birds to expend energy in avoidance of humans and reduces the time available for resting and feeding at a time in the annual cycle when fat deposition and energy conservation are important. Also, human disturbances can effectively cause habitat loss by displacing birds from feeding or resting habitat. Managers of natural resources are increasingly faced with decisions about the types and amounts of public use that should be allowed without lowering the value of the resource for wildlife. In order for managers to make decisions about how to minimize human impacts on waterbirds, information about the relative impacts of different types of activities upon the birds must be collected. I imposed five different experimental human disturbances on seven species of dabbling ducks wintering in an impoundment system at Back Bay National Wildlife Refuge, Virginia Beach. Virginia, to determine the responses of ducks and to learn which activities cause greater or lesser disturbance. The experimental treatments were a control (no human disturbance), an electric tram traveling at a speed of 10-15 mph. a truck traveling 10-15 mph ("slow truck"), the same truck traveling 30 mph ("last truck"), a person biking, and a person biking. The responses of ducks were dependent on the type of human disturbance, the distance the ducks were from the disturbances, and the species of ducks. Few birds were unaffected by the treatments. A person walking was significantly more disturbing than all of the vehicle treatments (tram and trucks) and the slow truck was significantly more disturbing than the fast truck. Of the birds sampled during "hiking" treatments, 63.7% flew away, flight being the most energetically demanding activity for waterfowl The management scheme in effect at Back Bay National Wildlife Refuge, a unique one among refuges, employs a combination of seasonal closures and spatial restrictions to minimize the effects of human disturbances on waterbirds. This management scenario should be used as a model for other natural resource managers charged with protecting wildlife while simultaneously providing opportunities for public use.


In Copyright. URI: This Item is protected by copyright and/or related rights. You are free to use this Item in any way that is permitted by the copyright and related rights legislation that applies to your use. For other uses you need to obtain permission from the rights-holder(s).