Keystone Predation

“Restoring an ecologically complete ecosystem in Yellowstone requires the return of willows--and with them, beavers. There's a clear threshold for ecosystem recovery. Willow stands must be more than 6 feet tall, the scientists found. That height is important, says Marshall. Then willows are beyond the reach of browsing elk, and can serve as seed sources for new young willows. Once willows have returned, beavers will gnaw down a certain number of them to build dams. The dams will further slow stream flow, allowing yet more willows to grow. The results offer new insights on the role of wolf-driven trophic cascades in the Yellowstone ecosystem, says Hobbs. Trophic cascades like that in Yellowstone occur when predators--or the lack thereof--in an ecosystem change the abundance or alter traits of their prey, in turn affecting the next lower trophic level.” ("National Science Foundation", 2013)

When feeding in a treacherous environment both prey and predator must develop a varied range of hunting and defense behaviors.

Additionally, avoiders often have a history of conflict with humans or may find themselves in specific habitat requirements in regards of reproduction as well as foraging, which can be unattainable within human settlements. Unfortunately, these species are also likely to experience high mortality rates as well as decreased reproductive rates when found within human dominated habitats. Mountain lions are also human avoiders but occasionally find themselves in conflict with communities due to the reoccurring conflict of eating livestock as well as pets.

This lab report focus on the risk of extinction of the panther species of Florida due to habitat loss (urbanization), collisions road kill, intolerance and poor genetic diversity have been confined to this animal to live in a small part of South Florida become one of the most endangered mammals on the planet. About 160 cats remain in the wild. Therefore the objective of this report is to disseminate knowledge regarding the extinction of native species by identifying the mortality, its causes, area of action, level of ecosystem and possible solutions to prevent their extinction

As the human population is increasing, Florida Panthers are decreasing. In the past, Native Americans would kill panthers for their coat, teeth, meat, and for medical uses (Alderson, pg. 23). There have also been several human-panther encounters where humans have tried to kill the panther. It is noted that panthers never try to come after individuals (Alderson, pg. 18). However; individuals still feel as if they are in danger when they are in contact with a panther. People also feel the need to harass and mess with Florida Panthers. With an increasing population, there are more people harming these animals. There have been several actions taken to prevent these occurrences from reoccurring. To avoid the amount of panthers being killed by humans there is laws in place that punishes people that bother, hurt, wound, agitate, or eradicate Florida Panthers (Alvarez, pg. 198). When an individual sees a panther they should not harm it; instead they should admire its

"Sport" hunting is a violent form of recreation that has left countless animals maimed, and orphaned animals vulnerable to starvation, exposure, and predation. This activity disrupts natural animal population dynamics and has contributed to the extinction of animal species all over the world, including the Tasmanian tiger and the great auk.(1,2)

Sea otters (Enhydra lutris) are marine mammals capable of spending their entire lives in water. Being carnivorous in nature, they feed on sea urchins, crabs, fishes, mussels and clams. They are referred to as keystone species due to their profound impact on marine ecology. The interaction between sea otters, sea urchins and kelp forests has been studied as a model for the impact of predator-prey interactions on community ecology. Sea otters are keystone predators, whose presence has a far-reaching influence on the marine food web by affecting the populations of sea urchins, which indirectly affects the populations of kelp

In this article, authors William Ripple and Robert Beschta focus on the issue of predation and the way it affects biodiversity and otherwise alters ecosystems. While many other studies have stressed the lethal effects of predation by carnivores, the authors of this study have chosen to focus on how nonlethal outcomes of predation affect the structure and function of ecosystems. The authors give two main objectives to their study: first to provide a short synthesis of the potential ecosystem responses to predation risk in a three-level trophic cascade involving large carnivores, hoofed animals, and vegetation; and secondly to present research that centers on wolves, elk, and woody browse species in the northern area of Yellowstone National

Many people believe they are part of the strong of the world. Although they could be considered stronger than others right now, they do not realize their position on the food chain can change. “The Most Dangerous Game” gives people the idea that world is divided between the hunters and the hunted, but it also gives us the situation of when there’s a hunter versus a hunter, one is surely to lose. As the world continues to change, the idea of hunters and huntees will remain, creating skilled predators, and leaving many animals falling to

We will attempt to verify that the predator-prey relationship of the Isle Royal of Michigan wolves and moose are also dependent on external factors such as the environment and man. Evidence suggests that this is the case but we intend to reproduce this factor in our model. Cross validation will be used to determine if earlier events can help predict known events that occur decades

The zooplanktons will therefore be released from predation and its biomass, the phytoplankton, will suffer the consequences by being decreased in their numbers. Because the number of top predators were altered, the whole food chain has collapsed from the imbalance of preys to predators. Moreover, there are lots of animals and not just a few that are impacted by cougars. The herbivores, the vegetations, and the decomposers are the biotic factors which gets impacted by the changes in the cougar populations. Lack of nutrients in the soil due to the lack of decomposers working in the soils, not enough photosynthesis due to lack of plants, and the changes in amount of water depending because of the overpopulation of animals drinking them are the abiotic factors that will be impacted. These are why keystone species are important for an ecosystem's key survival. By cougars eating animals such as deer, elk, moose, beavers, sheep, they prevent its “preys” from being gone. In their case, however, since these animals are mostly herbivores, their preys would be

One hypothesis proposes that the reason Steller sea lions have been declining is because of low prey abundance. Animals should use their energy efficiently when they forage to maximize the net amount of energy gained in relation to the amount time and energy that is spent, but it is believed that the reason Steller sea lions are disappearing in such big numbers is because when prey abundance is lower, that Stellar sea lions are less efficient predators (Charnov, 1976). In a recent study conducted on the effect of prey abundance on foraging efficiency, it was found that the less prey that Stellar sea lions had available, the less efficient they were in foraging (Goundie et al., 2015). In the experiment, the researchers took 4 adult Stellar sea lions and had them dive up and down a tube while recording their oxygen consumption, and dive duration. The sea lions dove between the surface of the water and depths of 10 m, and 40 m, and the reason for this was to simulate diving depths of Steller sea lions in the wild (Merrick and Loughlin, 1997). While the sea lions were diving, researchers fed them pieces of fish through two different tubes that were placed away from each other in order to simulate real foraging movements and prey densities. The researchers fed the seals 12 pieces of fish in the

Predators and prey are organisms that interrelate, and they can influence on another’s success in reproduction. Predators are organisms that consume other organisms-their prey. These two organisms evolve together. They live in an environment where they must develop certain adaptations to survive. When an adaptation is developed, it gives an organism certain physical characteristics that create an advantage for survival and can come to dominate in a population. An adaptation aids survival by either decreasing a prey's chance of being eaten, or by increasing a predator's chance of obtaining food to survive and reproduce. Predators must fight for food. They face density-independent

Sea otters (Enhydra lutris) are marine mammals capable of spending their entire lives in water. Being carnivorous in nature, they feed on sea urchins, crabs, fishes, mussels and clams. They are referred to as keystone species due to their profound impact on marine ecology. The interaction between sea otters, sea urchins and kelp forests has been studied as a model of the impact of predator-prey interaction on community ecology. Sea otters are keystone predators, whose presence has a far-reaching influence on the marine food web by affecting the population of sea urchins in particular, and kelp forests & other marine organisms in general. There has been a steep decline in sea otter populations due to water pollution and exploitation for

Majestic, noble, and brave, this famous iconic wild animal on the planet has captivated the people since the beginning of time. They are most feared by other animals thus, known as the king of the jungle – no other than the lions. Member of the genus Panthera, the lion is one of the big cats in the Felidae family. A lion’s head and body size average about 4.5 to 6.5 feet and tail of about 26 to 40 inches in length. A lion also weighs about 265 up to 420 pounds and a size relative to a 6-foot human. These mammals are also carnivores. Lions have always seen hunting in groups called pride. While lions generally avoid a full-grown elephant, lions still prefer their preys large like the zebras, buffaloes, and giraffes. Poised as the top animal in the ecological pyramid, lions have strong physical qualities, fascinating reputation, and an unfortunate decreasing number of population.