Predation

We often think of wolves of killing and wasting their food whereas in reality, “About half their meals come from kills, and on average 5 percent of their winter encounters with moose result in kills. The other half of their winter meals are scavenged (animals that died from other causes); the majority of the moose they eat are scavenged. They dig many of the scavenged meals from beneath the snow . . . pg. 87 (Haber & Holleman, 2013). Haber contends “Wolves are master hunters, but by no means are…

In Yellowstone National Park, there are more than 11 native fish species in the waterways, with the Yellowstone cutthroat trout historically being the most abundant fish in the park (NPS, n.d.). The cutthroat has been the dominate fish species in this area for hundreds of years, being fished by both the Native Americans who lived in this area and the wildlife. This fish is an integral part of Yellowstone’s ecosystem because they are relied upon as a keystone food source for birds, bears, river…

ecosystem, the density-dependent factors are known to be environmental factors which effects on a population change as the population density changes. But there are many examples of density-dependent factors that affect population growth are known to be predation, disease, and competition. Density-independent factors are environmental factors that affect the size of a population but are not influenced by changes in population density. But the two examples of density-independent factors that…

if any of the following factors are applicable: a) the present or threatened destruction, modification, or curtailment of it s habitat or range; b) overutilization for commercial, recreational, scientific, or educational purposes; c) disease or predation; d) the inadequacy of existing regulatory mechanisms; or e) other natural or manmade factors affecting its continued existence (Endangered Species Act, Section 4.(a) 1973). The primary factor that would warrant listing of this species is the…

Population and community-level impacts of feral cats on native fauna have been little studied, but evidence from several studies indicates that direct predation is the most important process involved (reference). Nevertheless, a study was conducted on the stomach contents of 390 feral felines in central Australia, between 1990 and 1994, in the Northern Territory. Felines victualed on a variety of invertebrates, reptiles, birds and mammals, including animals up to their own body mass in size.…

ADI Predator-Prey Population Size Relationship Lab Report In nature, there are many relationships between organisms. One of these is a predator-prey population size relationship, and more specifically for this investigation, predation. In this relationship, an organism (or organisms) depend(s) on others for food. There is a predator, the hunter, and the prey, the hunted. In this experiment, the predators were the wolves, and the prey were the sheep (the grass could also be considered prey, and…

June Beetle (Phyllophaga errans) and the Valley Grasshopper (Oedaleonotus enigma) (Hawbecker 1953). Many predators inhabit the NAS' range such as the Rattlesnake (Crotalus viridis), Red-Tailed Hawk (Buteo borealis), and numerous owl species, yet predation from these species on NAS is negligible (Hawbecker 1953). However, the Weasel (Mustela frenata) and the Badger (Taxidea taxus) have shown to prey on the NAS heavily (Hawbecker 1953). It has been…

One of the many definitions of a predator is an animal that lives by killing and eating other animals, or an animal that preys on other animals. Better yet, one that preys, destroys, and devours. According to Encyclopedia Britannica, predation is the pursuit, capture, and killing of animals for food. Excluding Homo sapiens, the animal kingdom has species considered to be top predators in the aquatic, terrestrial, and aerial territory. For instance, the massive great white shark is probably the…

Predator control programs have killed hundreds of native animal species in hopes to benefit livestock producers and to enhance game populations. However, the animals they are killing, beavers, wolves, and many other carnivores, are important benefactors of ecosystems. Bradley Bergstrom said in his article “License to Kill” that “leading ecologists have concluded that many of the world’s pandemics, irruptions of undesirable species and collapses of desirable ones, and destabilization of…

There are two major trophic cascades that scientist use. One is called bottom-up and the other is top-down. The controller of top-down would be the top predator or the apex predator (Wallach and O’Neill, 2009). The apex predator can also be known as the keystone species in that ecosystem. Top-down control is when the apex predator regulates the structure and population of the ecosystem (Wallach and O’Neill, 2009). The apex predators will prey on the consumers, which keeps the consumers…