Grackles

Numbering in the tens of millions of birds, grackle populations in North America can cause a variety of conflicts with people. Grackles eat agricultural crops and livestock feed, damage property, spread pathogens, and collide with aircraft. Their large roosts can be a nuisance in urban and suburban areas. A combination of dispersal techniques, exclusion, and lethal removal may help to reduce grackle damage. Grackles adapt easily to human-dominated environments, and exploit human food and other features of human landscapes. Thus, an integrated damage management approach to grackle damage focuses on reducing and eliminating the damage, rather than simply controlling grackle populations. Three species of grackles are present in North America: the common grackle, the boat-tailed grackle, and the great-tailed grackle. A fourth species, the greater Antillean grackle (Q. niger) is present in Puerto Rico. All are part of the Family Icteridae that includes blackbirds, orioles, cowbirds, meadowlarks, and bobolinks. The population status of all three grackle species is considered common to overabundant

Conflict of Atomism and Creationism in History

The underlying worldview assumptions of creationism are centered in reality, causality and unity-logical assumptions that came to be imbedded in science and the scientific method. Creationism has been opposed by atomism since Epicurus (342-270 B.C.) asserted that random events occur in matter. The early atomists developed a theory of matter to support a pantheistic worldview; in modern science, atomistic assumptions are implemented into current theories of matter, forces and cosmology. Recently, creationists have returned to the logical basis of science and developed phYSical models of elementary particles and atoms for a basic theory of matter. Numerous illustrations show how creationist worldview assumptions lead to superior explanations of the structure of matter and the nature of forces on objects

Feral Free-Ranging Horse Impacts to Native Wildlife

The impacts of introduced horse on the vegetative communities has been widely studied. However, minimal research has been conducted to scientifically determine how they affect native wildlife. Ecologically, feral and free-ranging horses have been documented to cause environmental effects including: soil loss, compaction and erosion; trampling of vegetation; reducing plant species richness; inducing mortality of native trees; damage to bog habitats; damage to water bodies; facilitation of weed invasion; altering composition of insects; crabs, fish, reptiles, birds and small mammals; and, keeping wildlife out of waterholes. The controversy surrounding management of horses and the continued growth of feral free-ranging horse populations will challenge the ability to properly manage habitat for wildlife into the future. We identify gaps in the literature and recommend that more peer-reviewed research would be beneficial in reducing the current public controversy surrounding management of feral horses

Is Razor-wire an Effective Deterrent for Birds Perching on Security Fences at Airports?

Wildlife-aircraft collisions (wildlife strikes) pose a serious risk to aircraft and cost civil aviation in the United States an estimated $957 million annually. Blackbirds and doves in particular have caused some of the most devastating aircraft accidents related to wildlife strikes in the United States and Europe. Birds perching on security fences and other structures are a problem at airports and other locations where birds are not desired. Reduction of available perching sites should make airports less attractive to these species and thus reduce the risk of damaging wildlife strikes. We conducted a series of experiments to determine if 3 species of birds hazardous to aviation [i.e., mourning doves (Zenaida macroura), common grackles (Quiscalus quiscula), and brown-headed cowbirds (Molothrus atar)] were deterred from perching sites at the top of a 3-stranded security fence by the application of Razor–ribbon™ Helical razor-wire. We determined bird use (for perching) of 3-stranded barbed wire security fences, with and without the addition of razor-wire using 6 birds each in 2 3.6- x 8.5- x 2.4-m flight cages. Treatment perches consisted of the top portion of a 3-stranded barbed wire security fence (2.5-m in length) with 2.5-m of razor-wire attached. Control perches consisted of an identical portion of security fence without the razor-wire. During the experimental period, mourning doves were observed on razor-wire protected fences twice as often, brown-headed cowbirds were observed similar amounts of time, and common grackles were observed 4 times as often as they were on unprotected fences. We found no evidence that razor-wire provided any deterrence to birds that perch on security fences

Suitable and Effective Coyote Control Tools for the Urban/Suburban Setting

Increases in the incidence of human conflict with coyotes in urban/suburban environments fuel a need for suitable coyote tools and methods to reduce these conflicts. Traditional tools, such as foothold traps and snares, face continued problems of acceptability in urban/suburban situations because of public anxiety about the risks to non-targets as well as other animal welfare concerns. We review the major categories of methods and tools used to prevent or reduce urban coyote-human conflicts, including exclusion (fencing), environmental and habitat modification, capture devices (traps, snares, and related devices), and shooting. We briefly discuss future technologies current under development: fertility control, toxicants, and electronic trap monitoring. Among capture devices, we describe recent advances in technology as exemplified by three devices: the KB Compound 5.5TM, the BélisleTM footsnare, and the CollarumTM, which have gone a long way to address both capture efficiency and animal welfare concerns. We caution those involved in advising legislators, or in drafting legislation, to be aware of developing technologies, so as to avoid writing laws that are so broad as to ban future capture devices that improve on current devices in terms of humaneness and animal welfare

Grackles

Numbering in the tens of millions of birds, grackle populations in North America can cause a variety of conflicts with people. Grackles eat agricultural crops and livestock feed, damage property, spread pathogens, and collide with aircraft. Their large roosts can be a nuisance in urban and suburban areas. A combination of dispersal techniques, exclusion, and lethal removal may help to reduce grackle damage. Grackles adapt easily to human-dominated environments, and exploit human food and other features of human landscapes. Thus, an integrated damage management approach to grackle damage focuses on reducing and eliminating the damage, rather than simply controlling grackle populations. Three species of grackles are present in North America: the common grackle, the boat-tailed grackle, and the great-tailed grackle. A fourth species, the greater Antillean grackle (Q. niger) is present in Puerto Rico. All are part of the Family Icteridae that includes blackbirds, orioles, cowbirds, meadowlarks, and bobolinks. The population status of all three grackle species is considered common to overabundant

New Method to Calculate Electrical Forces Acting on a Sphere in an Electrorheological Fluid

We describe a method to calculate the electrical force acting on a sphere in a suspension of dielectric spheres in a host with a different dielectric constant, under the assumption that a spatially uniform electric field is applied. The method uses a spectral representation for the total electrostatic energy of the composite. The force is expressed as a certain gradient of this energy, which can be expressed in a closed analytic form rather than evaluated as a numerical derivative. The method is applicable even when both the spheres and the host have frequency-dependent dielectric functions and nonzero conductivities, provided the system is in the quasistatic regime. In principle, it includes all multipolar contributions to the force, and it can be used to calculate multi-body as well as pairwise forces. We also present several numerical examples, including host fluids with finite conductivities. The force between spheres approaches the dipole-dipole limit, as expected, at large separations, but departs drastically from that limit when the spheres are nearly in contact. The force may also change sign as a function of frequency when the host is a slightly conducting fluid.Comment: 29 pages, 8 figures, Accepted for Publication in Physical Review

NONLETHAL CONTROL TECHNIQUES USED TO MANAGE BLACKBIRD DAMAGE TO SUNFLOWER

Since 1986, nonlethal management techniques have been used by the North Dakota and South Dakota Animal Damage Control programs to reduce blackbird damage to sunflower. The use of propane cannons, pyrotechnics, hazing, and cattail management is discussed. Currently, the primary program for both States is cattail management

NONLETHAL CONTROL TECHNIQUES USED TO MANAGE BLACKBIRD DAMAGE TO SUNFLOWER

Since 1986, nonlethal management techniques have been used by the North Dakota and South Dakota Animal Damage Control programs to reduce blackbird damage to sunflower. The use of propane cannons, pyrotechnics, hazing, and cattail management is discussed. Currently, the primary program for both States is cattail management

Developing Alternatives to Protect Domestic Sheep from Predation in South Africa

South Africa has approximately 8,000 commercial small livestock farms and 5,800 communal/subsistence farmers throughout the country. Reported rates of small livestock loss to predation range from 3-13% and 0.5-19% from communal farming areas. A range of predators exist on the African continent, but in southern Africa major livestock losses are primarily due to black-backed jackal and caracal. South Africans have been managing caracals and jackals for over 300 years with no elimination of predation. During the aforementioned time frame, producers have used and/or developed a number of techniques including lethal, nonlethal, and integrated predator damage management to address predation losses. In the Karoo area of South Africa, one producer decided that a new way needs to be developed after losing over 60 lambs in a month, while practicing continuous removal of caracal and black-backed jackal. His integrated predator damage management system includes using a prototype nonlethal collar system for sheep and lambs. The collars are used to train dominant pairs of predators to avoid predation while maintaining their territories and keeping transient predators out of the area. The system has now gone into production in South Africa and is being distributed by its inventor