Human Disturbances to Waterfowl: An Annotated Bibliography

Introduction

Increases in human population, transportation, recreational boating, industrial and residential development, birdwatching, camping, and hiking all create conflicts with waterfowl which must use a dwindling and fragmented habitat base. Managers and administrators require information on the types, magnitude, and potential effects of disturbances that will affect human use of and access to wildlife resources. Managers responsible for waterfowl production should be aware of the problems created by human disturbance to aid them in the design of facilities and developments to increase public appreciation of waterfowl.

This bibliography resulted from concerns about human disturbance to flocks of canvasback ducks (Aythya valisineria) and other waterfowl that stage on navigation pools of the Upper Mississippi River during fall migration. Initially, a field study and subsequent literature search for information to use in a manuscript describing these disturbances (Korschgen et al. 1985) indicated that few specific studies had been conducted on the subject, although there were numerous anecdotal references. Aspects of human disturbance to other groups of wildlife, especially large game mammals (e.g., Bollinger et al. 1973; Ream 1980; Ferguson and Keith 1982) and nesting seabirds and shorebirds (e.g., Hunt 1972; Robert and Ralph 1975; Buckley and Buckley 1976; Manuwal 1979; Rodgers and Burger 1981; Burger 1981; Whitman 1988; Frederick and Collopy 1989; Strauss and Dane 1989; Yalden and Yalden 1990), have received considerable attention because of the increased frequency of human-wildlife interactions in national and state parks, refuges, management areas, and seashores (Foin et al. 1977; Purdy et al. 1987; Pomerantz et al. 1988). Books have been written relating to effects of human disturbance on natural resources (Edington and Edington 1986; Hammitt and Cole 1987). We decided that a consolidated information source on human disturbances to waterfowl would be of value to waterfowl managers and administrators.

We searched Wildlife Abstracts, Wildlife Review, Journal of Wildlife Management, Wildlife Society Bulletin, and Wildlife Monographs for titles and key words related to human disturbance. Unfortunately, few key words used by journals relate to this topic. We also searched a bibliography of waterfowl papers maintained by Kenneth J. Reinecke (U.S. Fish and Wildlife Service, Patuxent Wildlife Research Center) that contains over 5,000 citations. Perhaps our most valuable source of information was the reference sections of publications dealing with human disturbances to waterfowl.

Some of the bibliographic entries are papers that did not directly pertain to waterfowl, but the topics may be important for further research related to waterfowl.

The definition of human disturbance to waterfowl varies among authors. The following definition seems reasonable to us: a direct event, intentionally or unintentionally created by people, leading to a reaction of alertness; fright (obvious or inapparent); interruption of activities; flight, swimming, or other displacements; or death or disablement. The event may have long-term or short-term effects. We have excluded almost all references dealing with death of waterfowl including: hunter harvest or illegal harvest, waterfowl collisions with power lines, deaths from the ingestion of angler's lead sinkers, losses of diving ducks to commercial fish nets and trotlines, and losses of waterfowl to furbearer trapping during spring seasons that are no longer in existence. Sometimes it was so awkward to exclude these subjects that we included them, but our intent was to confine ourselves chiefly to disturbance caused by direct human activity (presence, traffic, flights, fishing, boating, and so forth).

We included several papers relating to waterfowl energetics because disturbances may hinder the acquisition of food (energy) which may affect fitness for migration and breeding. Energetics is a rapidly developing topic that will be important in answering some of the questions about the effects of disturbance that cannot now be answered.

The frequency of topics in the subject index is shown in Table 1. Disturbances created by water users, chiefly boaters, anglers, and hunters, are mentioned most frequently. These disturbances were serious in that they displaced waterfowl from their feeding grounds, created energetic costs associated with flight, and affected nesting or brooding waterfowl, which may have lowered productivity. Interestingly, researcher-caused disturbances also had a high frequency of occurrence. Most biologists are familiar with the desertions of females caused while conducting nesting studies.

We hope this bibliography will stimulate research and focus on those areas most lacking in definitive data. Despite our efforts to include all the pertinent references, this bibliography is incomplete. It provides, however, a starting point for the reader interested in human disturbances to waterfowl.

Acknowledgments

This project was begun under the direction of R. F. Berry, Manager of the Upper Mississippi River Refuge Complex. We particularly thank the following persons for their encouragement and aid: D. V. Bell, Senior Research Officer of the Wildfowl Trust, Slimbridge, England; R. B. Kahl, Wisconsin Department of Natural Resources; L. A. Batten, Senior Ornithological Advisor and Chief Scientist Directorate, Nature Conservancy Council, Peterborough, England; and L. H. Fredrickson, Director of the Gaylord Memorial Laboratory, University of Missouri. We are indebted to many researchers, both in America and in Europe, who supplied reprints of their work. Most important has been the patient and thorough assistance of A. Zimmerman, librarian at the Northern Prairie Wildlife Research Center, who obtained many of the publications and provided editorial comments on the manuscript. J. Sauls and S. H. Thatcher, translated German papers. D. Stroud and J. Magerus, University of Wisconsin-La Crosse, translated German and French papers. We are also grateful to A. Prochowicz, L. Ames, B. Toal, C. Eloranta, and H. Sampson who typed and checked the manuscript.

Literature Cited