The Lotka-Volterra Predator-Prey Model

Predators/prey relationships play a big role in animal populations. If the balance between predators and prey is changed, populations are changed. The white- tailed deer populations in some areas has grown too large because there are no natural predators.

The local animals population is decreasing because the Python snakes are eating them. According to the text, “With no natural predators, these eating machines appear to be wiping out huge numbers of opossums, raccoons, and bobcats, as well as many bird species." This supports that the local animal population is decreasing because the snakes are eating the animals since the python snake population is growing then the other animals population is decreasing. The more snakes

Say a frog eats a caterpillar, then a snake eats the frog, then finally a owl eats the snake. This is just a simple food chain but something called biodiversity, which means that’s there is a variety of things a that one animal can eat. An owl cant only eat a snake it could eat the frog or something smaller like a worm. This keeps form one species dying out completely, which would cause multiple species to die out. When someone releases a pet into the wild they are causing a disturbance into the wild habitat. When a python is released into a place full of crocodiles these two will start competing for food which would cause all of the lower species to start lowing in numbers faster until they become extinct which would then make the snakes and the crocodile die off too. If this keeps on happening the eventually every animal would die off!

-Reintroduction of a top predator lowered the number of over grazing herbivores, leaving a more stable amount of food for many species of herbivores.

Extinction: Most species become extinct because they can’t cope with the environmental change, and also because of introduced species that turned into competitors for

Since organisms living in communities form interdependent relationships, a change in the abundance of one species will not only affect the physical and more direct interactions, but could indirectly affect the number of other species within the community as a consequence (Wootton 1993). These indirect affects rise because the interactions between pairs of species are not independent of other species, such as increasing the density of vegetation may increase the survival rate of the prey, reducing the intensity of the interaction between the predator and prey (Wootton 1993, 1994). An

For example, their concept indicates that prey species will alter their foraging habits to the features of the terrain in order to avoid areas with a high risk of predation. Predation risk in a changing environment is also focused on by the authors. There are many environmental variables that may influence the degree of predation risk such as weather, wildfires, and other conditions that influence ungulates’ access to vegetation. Finally, the authors focus on ecosystem responses to trophic cascades—primarily on riparian functions and on beaver and bird populations. They also inform us that wolves may represent an indirect control on beaver populations as well as cause ungulates to avoid some riparian areas—therefore reducing herbivory on wooden browse species.

In the YouTube video “How Wolves Change Rivers” published by Sustainable Human, the narrator argues that the introductions of wolves to Yellowstone National Park not only altered the ecology of animals, but that they also brought upon massive improvements to the luscious environment as well. The author brings upon the conversation by discussing a term used in the food chain called the “trophic cascade”, a term that describes how the introduction of an organism at that top of the food chain can

The ecosystem consists of communities with different populations of species. Each diverse animal in the ecosystem has a unique way of surviving the abiotic and biotic factors in the environment through its traits; behavioral traits, morphological traits and physiological traits. Some of its traits prevent these organisms from predation, and others allows organism to survive when temperature are too high or too low. The strategy to survival depends on the animal. Let’s talk about the Procyon lotor also known by the name raccoon (Source 2).

This project plans on modeling a dynamic system predator-prey relationship. The wolf-moose relationship of Isle Royal represents a unique location where moose is solely preyed upon by wolves. And wolves prey mostly just on moose; however, it has been noted that beavers have been a secondary food source. The wolf and moose population in this locale has been studied thoroughly and population statistics have been recorded for over 50 years. Evidence supporting external factors that have had an effect on the populations

In a time where the environment is experiencing significant change, it is important that certain communities and individuals be informed of what is occurring. This said environmental change can be observed in the way the seasons affect organisms and their habitat, which leads to an impact on their predator-prey relationships. This relationship between the California mountain lion, mule deer, and coyote that live at Wind Wolves preserve is being studied, along with their seasons. These animals can live in separate regions, but do have overlapping territories. Three of which being Twin Fawn, Site 1, and Site 2. Their environment can change how a predator hunts or how a often or long a prey appears at a certain location.

Parasitic wasps and flies lay their eggs either in the egg masses or in the larvae of tussock moths (Wickman et al. 1981). Spiders, predaceous insects, and birds also prey upon all life stages of the Douglas-fir tussock moth (Brooks et al. 1978). These parasites and predators are only effective when populations of Douglas-fir tussock moths are low, due to the concept of predator satiation. This concept basically says that predators receive enough food when populations of the prey are high, but hunt their prey more intensively when prey populations are low (Harrison and Wilcox 1995). Harrison and Wilcox (1995) showed this with tussock moths in that outbreaks could be prevented by introducing predators of tussock moths when moth population numbers were

Figure \ref{fig:no5} shows that the animal populations continue to oscillate, with relatively constant maximum and minimum values and period.

In 1977 there was an increase in certain species of lions and seals in British Columbia, while in Alaska there was a decrease of seals and sea lions (Williams et al. 2004;Trites et al. 2007). Because this happened after commercial whaling, many attribute the decline with cascading top-down effect (Trites et al. 2007). There are many other factors that make an impact and based on research the removal of the whales did not cause the shift in seals and sea lions (Trites et al. 2007). Most studies are conducted to focus on the predator and a species of prey of a neighboring trophic layer (Baum and Worm 2009). Another whale influencing this environment is the Killer whale (Williams et al. 2004). These need an incredibly high calorie diet

It is important to know information about the predators and prey species in an ecosystem. The focus of predator management is to minimize predation using nonlethal and lethal methods. Carnivores are vital for biological systems. Removing predators that eat the prey will cause a decline in the plants biomass. Problems with predation can be heavily influences by humans. Impacts on predators or prey can be from global warming, habitat loss, War, etc. Adult porcupines are one of the many species that are affected by global warming. Any prey species that molts to white pelage early in the winter due to global warming may expose themselves to predators easier because, if there is a heat spell, white fur will not be effective camouflage with loss of the snow. Other contributors for the decline of prey can be from drought which could dampen the amount of available resources or from interspecific completion for a common resource. There are some ethic and non-ethic methods used for managing predators. Both methods can be used but, are better at different scenarios. Using lethal methods is controversial because it can conflict with public opinions, laws and regulations, animal rights, etc. Predator management is costly depending on the action taken. Economic loss in agricultural livestock from predators is one of the main conflicts that is dealt with to manage predators.