Evaluation of Dimethyl Anthranilate as a Nontoxic Starling Repellent for Feedlot Settings

Few objective estimates are available, but starling (Sturnus uulgaris) and, sometimes, blackbird (e.g., Agelaius phoeniceus) depredations at feedlots are considered serious economic problems (Besser et al. 1967, 1968; Feare 1975, 1980; Stickley 1979; Twedt and Glahn 1982). Losses may result either from feed contamination and disease transmission or, more likely, from feed consumption (Besser et al. 1968; Russell 1975; Twedt and Glahn 1982). These problems are exacerbated by the use of complete diets (Rickaby 1978) which are presented in open troughs to which starlings have access. Feare and Wadsworth (1981) have shown that these birds can take up to 9% of the high protein fraction of the diet, thus depriving cattle of their high energy source and altering the composition of the entire ration. Efforts to control problem birds at feedlots have focused mainly on attempts to trap or kill birds with mechanical devices or chemical agents (Besser et al. 1967; Bogadich 1968; Levingston 1967; Westetal.1967; Feareetal.1981). These approaches, however, fail to create a suboptimal environment for avian feeding activity, and birds rapidly reinfest feedlots when control measures are relaxed (Twedt and Glahn 1982). Additional problems arise when lethal chemicals; such as Starlicide (1% C-chloro-p-toludine hydrochloride on poultry pellets) are used, including: (1) potential primary and secondary hazards to nontarget animals (e.g., Cunningham, 1979), (2) bait aversion by target birds, (3) expense and labor in prebaiting, baiting and monitoring (Glahn 1981) and (5) rather short-term effectivenses when large numbers of birds are in the area (Feare et al. 1981)

FACTORS INFLUENCING ARIZONA BAT POPULATION LEVELS

Current (1969 and 1970) estimates were compared with past estimate of numbers of members of over 20 Arizona and northern Mexico bat populations, and trends established. A trend is defined here as the change in numbers of population members between the present estimate and the most recent past estimate in the same month at the same roost site. Thirteen of the populations showed definitive trends: nine Down , one Stable-Down , one Stable”, and two Up , Eight of the nine populations with Down trends contained no live members on the 1969 and 1970 visits, and no signs of members. The ninth contained 1% of the numbers in the present estimate that it had on the most recent past estimate of the same month. Human disturbance was frequently associated with populations showing Down trends, while lack of human disturbance was characteristic of stable or increasing populations. Human disturbance directed at the population members, oversampling for biological study probably resulted in the loss of an Antrozous pallidus population. Human disturbance directed at the roost site, modernization of a railroad bridge, resulted in the loss of favored roost site and possibly direct loss of some population members for an Eptesicus fuscus and a Tadarida brasiliensis population.Insecticide residue analysis was performed on 104 samples from 58 bats representing six species: Antrozous pallidus, Eptesicus fuscus, Leptonycteris sanborni, Macrotus waterhousii, Pipistrellus hesperus, and Tadarida brasiliensis. Samples included pooled brains, livers, GX tracts + contents, mammaries, embryos, and remaining whole bodies. Preparation was accomplished by a Quickie Method that works particularly well for samples weighing 10 g or less, and analysis by gas chromatography. DDE, DDD, DDT, o,p\u27-DDT, dieldrin, toxaphene, Aroclor 1254 and Aroclor 1260 were seen in one or more samples. DDE was usually present in greatest concentration. Residues in organs and embryos ordinarily reflected those in their hosts, but in less concentration. Embryo/host

FACTORS INFLUENCING ARIZONA BAT POPULATION LEVELS

Current (1969 and 1970) estimates were compared with past estimate of numbers of members of over 20 Arizona and northern Mexico bat populations, and trends established. A trend is defined here as the change in numbers of population members between the present estimate and the most recent past estimate in the same month at the same roost site. Thirteen of the populations showed definitive trends: nine Down , one Stable-Down , one Stable”, and two Up , Eight of the nine populations with Down trends contained no live members on the 1969 and 1970 visits, and no signs of members. The ninth contained 1% of the numbers in the present estimate that it had on the most recent past estimate of the same month. Human disturbance was frequently associated with populations showing Down trends, while lack of human disturbance was characteristic of stable or increasing populations. Human disturbance directed at the population members, oversampling for biological study probably resulted in the loss of an Antrozous pallidus population. Human disturbance directed at the roost site, modernization of a railroad bridge, resulted in the loss of favored roost site and possibly direct loss of some population members for an Eptesicus fuscus and a Tadarida brasiliensis population.Insecticide residue analysis was performed on 104 samples from 58 bats representing six species: Antrozous pallidus, Eptesicus fuscus, Leptonycteris sanborni, Macrotus waterhousii, Pipistrellus hesperus, and Tadarida brasiliensis. Samples included pooled brains, livers, GX tracts + contents, mammaries, embryos, and remaining whole bodies. Preparation was accomplished by a Quickie Method that works particularly well for samples weighing 10 g or less, and analysis by gas chromatography. DDE, DDD, DDT, o,p\u27-DDT, dieldrin, toxaphene, Aroclor 1254 and Aroclor 1260 were seen in one or more samples. DDE was usually present in greatest concentration. Residues in organs and embryos ordinarily reflected those in their hosts, but in less concentration. Embryo/host

Obtaining Assistance to Control Wildlife Damage

The Wildlife Society (TWS) policy statement for wildlife damage control (1992) states: “Prevention or control of wildlife damage . . . is an essential and responsible part of wildlife management.” The role of wildlife damage control in our society is changing and so is public perception of it. This change is recognized among wildlife managers and researchers. Efforts are under way to make the wildlife damage control profession more responsive to concerns of society. Formal petition for the establishment of a Wildlife Damage Working Group within TWS was made to the Wildlife Society Council on March 21, 1993 and the following day the council approved interim status for the working group. Wildlife damage control professionals should be prepared to promptly supply the best information available to solve conflicts between people and wildlife. Often, the most urgently needed information is where to go for assistance when a problem arises. This chapter provides options for obtaining assistance. It tells who does what to minimize conflicts between people and wild animals, and it gives suggestions for obtaining self-help information and/or reaching people who can provide onsite help