River Size and Fish Assemblages in Southwestern South Dakota

We studied relations between river size, fish species diversity, and fish species composition along four major rivers in the Great Plains of southwestern South Dakota to assess patterns of species diversity and composition. We expected diversity to increase with river size and fish composition to change via species addition downstream. Previous surveys of 52 sampling stations provided fish assemblage data, and we used the Geographic Information System (GIS) to determine watershed area by station. Watershed area did not predict species richness or species diversity (Fisher's a), so species richness of 12 ± 3.5 SD species and Fisher's a of 2.3 ± 0.87 SD characterized species diversity in the study area. Cluster analysis of faunal similarity (Sorensen's Index) among the 52 sampling stations identified two geographically distinct faunal divisions, so species composition was variable within the study area, but changed via species replacements among faunas rather than species additions downstream. Nonnative species were a minor component of all faunas. Uniform species diversity may be a recent phenomenon caused by impacts of Missouri River dams on native large-river fishes and the unsuitability of rivers in the Great Plains for nonnative species. Variation in faunal composition may also be recent because it was affected by dams.

PHOTOGRAPHIC RECORDS — THEIR IMPORTANCE IN TODAY'S ENVIRONMENTALLY SENSITIVE BIRD MANAGEMENT PROGRAMS

We are living in a day of change. Environmental awareness is a part of our everyday life in a way unprecedented in history. The courts, in their infinite wisdom, have initiated the joint and several liability (deep pocket) rules that make everyone at risk in almost all situations. Bird management programs, by their very nature, are extremely sensitive. Any project, if not evaluated, planned, carried out, and documented properly can result in adverse regulatory agency action, bad publicity, and even fines or lawsuits. Proper photographic documentation can play a vital part in helping to provide the necessary records to help prevent problems and/or defend yourself in case of lawsuit or regulatory action. In the preparation of this paper, we surveyed state pesticide lead agencies, state Department of Conservation (Fish and Wildlife) agencies, some U.S. Fish and Wildlife Law Enforcement personnel, and several individuals to get their reaction to and their comments about this concept of supplemental recordkeeping. Of those responding, a majority thought the concept of supplemental photographic recordkeeping would be an asset to individuals and organi¬zations conducting bird management projects.

THE EFFECT OF INTENSE LIGHT ON BIRD BEHAVIOR AND PHYSIOLOGY

It has been known for centuries that light (photoperiod) is possibly the major environmental stimuli affecting bird behavior and physiology. The length of the light period stimulates the breeding cycle, migration, fat deposition, and molt in most species of birds. Therefore, it is only natural that one would think of using light as a means of bird control. In fact, light has already been used as a bird control; flood-light traps have been used to trap blackbirds (Meanley 1971); Meanley states that 2000-W search lights have been used to alleviate depredation by ducks in rice fields. Pulsing light is already used on aircraft, aircraft hangers and high towers as a means of detourinq birds (Schaefer, 1968). With some positive results already obtained with light as a bird control, the next step is to see if a better light source (the laser) might not have a greater effect. The laser is basically an intense and coherent light with extreme directivity and, thus, might have greater influence on a bird’s behavioral and physiological responses.

Temporal and Spatial Patterns of Avifauna on Wetlands in the Vicinity of Bush Field Airport, Augusta, Georgia, USA

Responding to a U.S. Federal court order to improve discharged wastewater quality, Augusta, Georgia initiated development of artificial wetlands in 1997 to treat effluents. Because of the proximity to Augusta Regional Airport at Bush Field, the U.S. Federal Aviation Administration expressed concern for potential increased hazard to aircraft posed by birds attracted to these wetlands. We commenced weekly low-level aerial surveys of habitats in the area beginning January, 1998. Over a one-year period, 49 surveys identified approximately 42,000 birds representing 52 species, including protected Wood Storks and Bald Eagles, using wetlands within 8 km of the airport. More birds were observed during the mid-winter and fall/spring migratory seasons (1,048 birds/survey; October - April) than during the breeding/post-breeding seasons (394 birds/survey; May - September). In winter, waterfowl dominated the avian assemblage (65% of all birds). During summer, wading birds were most abundant (56% of all birds). Habitat changes within the artificial wetlands produced fish kills and exposed mudflats, resulting in increased use by wading birds and shorebirds. No aquatic birds were implicated in 1998 bird strikes, and most birds involved could safely be placed within songbird categories. Airport incident reports further implicated songbirds. These findings suggested that efforts to decrease numbers of songbirds on the airport property must be included in the development of a wildlife hazard management plan. Seasonal differences in site use among species groups should also be considered in any such plan. Other wetlands within 8 km of the airport supported as many or more birds than the artificial wetlands. With proper management of the artificial wetlands, it should be possible to successfully displace waterfowl and wading birds to other wetlands further from the airport.

BIRD HAZARDS TO AIRCRAFT

When I spoke to the third Bird Control Seminar in 1966 on "Ecological Control of Bird Hazards to Aircraft", I reviewed what we had accomplished up to that time. I spoke about the extent of the problem, the bird species involved and the methods we used to make the airports less attractive to birds that created hazards to aircraft. I wish to discuss today our accomplishments since 1966. I have presented a number of papers on the topic including one with Dr. W. W. H. Gunn, in 1967 at a meeting in the United Kingdom, and others in the United States (1968 and 1970) and at the World Conference on Bird Hazards to Aircraft in Canada in 1969. There is no longer any question about the consequences of collision between birds and aircraft. Aircraft have not become less vulnerable either. Engines on the Boeing 747 have been changed as a result of damage caused by ingested birds. Figures crossing my desk daily show that while we are reducing the number of serious incidents and cutting down repair costs, we will continue to have bird strikes. Modification of the airport environment (Solman, 1966) has gone on continuously since 1963. The Department of Transport of Canada has spent more than 10 million dollars modifying major Canadian airports to reduce their attractiveness to birds. Modifications are still going on and will continue until bird attraction has been reduced to a minimum.

THE ROLE OF BIRD MANAGEMENT IN FIRE PROTECTION

Two years ago, Mike Fall and I showed you some ideas we had regarding mod¬ern architecture and bird problems. This year we've switched to considering bird hazards in older frame dwellings and on buildings where a fire hazard may be ap¬parent. During a class project some time ago, I was examining a nest of house sparrows and discovered that these birds incorporated cellulose cigarette filters into their nests. Filters were stripped of their paper wrapping and were apparently used by the sparrows as a substitute for or a supplement to fluffy air-born seeds and seed mat¬erials. The incidence of the cigarette filters varied. In the nests that I sampled the numbers varied anywhere from six up to two dozen filter remnants. We feel that the incidence will probably vary with the relative availability of discarded cigarette filter butts. We are concerned with the incidence of filters as an index to the possibility that the birds are picking up live cigarette butts, and this leads us to investigate some records of fires over the past three quarters of a century that were claimed to have been caused by birds.

BIRD DEPREDATION ON RICE AND OTHER GRAINS IN ARKANSAS

In Arkansas, blackbirds are responsible for appreciable damage to rice, grain sorghum, oats, wheat, rye, and corn. By far, the greatest damage is to rice. As is shown in the following table, the losses to rice producers amounted to an estimated $3,049,055 in 1968, the last year that a survey was made. Nearly two-thirds (63%) of this loss was to standing rice destroyed and to the cost of bird control measure in standing rice. The remaining losses ($2,140,320 ) are to seeding or to efforts to control bird depredations to new seeding, (see Table 1). Blackbird damage to grain sorghum and corn was mostly to standing grain; that to oats, wheat and rye, to seeding, although there is occasional damage to standing grain. Additional problems are caused by blackbirds in feed lots. The total losses to Arkansas agricultural producers due to blackbirds in 1968 was about $3,500,000. Bird damage in a specific locality and on specific crops seems to vary in intensity from year to year. However, surveys during the past ten years suggest a fairly consistent level of total damage state-wide. The damage in 1968-and I believe in 1969—was somewhat lighter than we have come to expect from past exper¬ience. (See table 2.) On a per acre basis the damage in 1968 showed a considerable decline when compared to previous years. A part of this decline is probably a temporary situation. Some of the decline in losses to rice and grain sorghum, however, are due to changes in varieties, such as development of bird-resistant milo, and to changes in cultural methods. Further appreciable reductions due to changes in these factors seem unlikely, (see table 3.) Since rice producers sustain the greatest losses to birds, they have generated the greatest demand for bird control programs. Three species are responsible for most of the damage to rice. They are the red-winged blackbird, common grackle and brown-headed cowbird. These birds have created problems for rice producers since the first successful rice crop was grown near Lonoke, Arkansas, in 1904.