Standard Procedures For Sign Concordance

A group of researchers collected data to support the theory that the overpopulation of snakes is killing off the mammal population. Ashley Townsend, National Geographic writes, “the python population has continued to grow at a remarkable rate and has caused great distress to the park 's ecosystem.” For this study, the researchers at the South Florida Water Management District recorded the rates of live and dead mammals during a nocturnal road survey and compared it to the 1996-1997 road surveys. Scientists for the South Florida Management District, stated, “Researchers noted that the animals in the park were dying at a greater rate since the python population has gotten so enormous.”

The aims of using VORTEX (Lacey and Pollak, 2014) was to analyse the success of management strategies including controlled hunting, supplementation, habitat restoration and corridors or a combination. VORTEX takes into account random events such as catastrophes running through iterations (replicas) to generate outcomes (Lacy, 1993). Each outcome will be assessed using probabilities of survival, genetic diversity and mean population sizes over a 200 year period.

As an invasive species, the Burmese python has an immense impact on the native populations of the Everglades. In the last 20 years, observations of mammals in the Everglades have declined by 95% while the number of non-native Burmese pythons in the park has significantly increased (Sovie et al. 2016). Data from game cameras used in a study by Willson support this observation, showing the spatial pattern of mammal abundance being inversely correlated with spatial expansion of Burmese pythons in the Everglades (Willson 2017).

“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)

The Point Arena mountain beaver (Aplodontia rufa nigra) is a federally listed endangered subspecies that is restricted to the small area of Point Arena, in coastal Mendocino County, California (Zielinski, et al., 2013). (See Figure 1). The Point Arena mountain beaver is a dark brown, medium-sized burrowing rodent with small ears and eyes, and long whiskers and claws (National Park Service (NPS), n.d.). The subspecies is semi-fossorial, spending most of its five to six year lifespan in underground burrows (United States Fish & Wildlife Service (USFWS), 2011). The burrows are typically found on moist and steep north-facing slopes or in well-drained gullies; each burrow contains separate chambers for food storage, nesting, and excrement (NPS,

Many species vital to ensuring that today’s environment will thrive are becoming extinct. If a species is slowly dwindling, and in imminent danger of becoming nonexistent, this species is considered to be endangered. “One in four mammals, one in eight birds, one third of all amphibians and 70% of the world’s assessed plants on the… IUCN Red List are in jeopardy” (IUCN, 2016). According to the International Union for Conservation of Nature, or IUCN, upwards of 16,000 species are threatened with extinction, including both plants and animals (IUCN, 2016). Before becoming endangered, a species will show warning signs, either by starting to lose biological diversity or by losing the habitats for that species to flourish in, or in the worst case, both. The word endangered can sometimes be confused with threatened, extirpated, or extinct. Extirpated refers to the state of a species where its population has died out in a certain area or range, but other populations of said species still exist elsewhere (Olden, Julian D., 2008). When a species is considered threatened, or vulnerable, this refers to the state of the species being susceptible to endangerment and extinction (“Extinction crisis escalates”). So if a species is threatened, the first signs of endangerment come along, which are similar signs to that of a species in danger of becoming threatened, including lack of genetic diversity, or overhunting may be evident. (“Extinction crisis escalates”). When a species is labelled

Within the Endangered Species Act, the U.S. Fish and Wildlife Service helps watch over and investigate the health of different species. Then, local and national scientist collects data to determine if a species gets put on the Endangered Species list. The main factor to determine the endangerment of a species is if a large percentage of the species’ habitat has been destroyed. Next, note if the animal’s population has been excessively decreasing, threatened by disease, or any terrorized by any predators. Also, record any man-made

Species often face multiple threats. We considered the relative impact of three major threats on populations of the San Joaquin kit fox. This species was once widely distributed across the southern San Joaquin Valley, but agriculture and development have replaced much of the now endangered subspecies’ habitat. We modeled impacts of climate change, land-use change, and rodenticide exposure on kit fox populations using a spatially explicit, individual-based population model. Our study indicates that landuse change will have the biggest impact on kit fox populations, with the potential to decrease populations by approximately 9% under a compact growth scenario or 15% under a business-as-usual scenario. 55% of the best kit fox habitat also has

The salt marsh harvest mouse is listed as an endangered species in 1970s. Its phylogeny is of the Kingdom Animalia, the Phylum Chordata, the Class Mammalia, the Order Rodentia, the Family Cricetidae, the Genus Reithrodontomys, and the Species raviventris. The closest living relative of the salt marsh harvest mouse, according to genetic mapping, is the plains harvest mouse, R. montanus, a western interior species that are found in Mexico and central US.

Throughout history, species have evolved and evolved over time. Evolution is caused by many factors some of which include natural selection, mutations, genetic drift, neutral or random evolution, migration or gene flow. Unlike evolution, many species are being extinct such as the Baiji River Dolphin, the Javan tiger, and golden toad. Before these organisms extinct, they were first endangered. An endangered specie is a specie on the brinck of extinction. This is the case of the swift fox, also known as Vulpes velox. For decades, scientists have thrived to keep the Vulpes velox from extinction through many means. To understand the swift foxes’ lifespan, one must learn their history and background, reasons they’re declining in numbers, historical homeland and present homeland and finally factors that caused this decline.

My trip to the La Brea Tar Pits, taught me of the biodiversity that was within California, from the Columbian Mammoths, Shasta Ground Sloth, Dire Wolves, and Sabretooth Cats. The museum emphasized that most of the extinct animals that were on display were extinct due to climate change or hunted by the earliest tribes throughout California and North America. The museum points out that most of these animals were large, but doesn’t show the reason as to why the larger animals went extinct, but the smaller animals survived the extinction. The museum also mentions that night-stalking animals weren’t found in the pits as during the cool temperatures throughout the evening would solidify the asphalt. This extinction was known as the Pleistocene

Abstract: There is very little known about the Salt Marsh Harvest Mouse (SMHM). In 1970, SMHM was added to the endangered list, largely due to the fact their salt water habitats 84% gone. With the mouse being just under 3 inches in length, nocturnal, loving its dense cover protection, and the close resemblance to the Western Harvest Mouse, it makes field identification very difficult. Further research is needed not only into the population numbers of SMHM, but its habitat as well. Capture-recapture will be used to assess the SMHM population, where it will be measured, weighed, a patch of hair taken for re-identification, and released back into its habitat. Subplots will also be measured for the Pickleweed population using USFS protocol. Despite conservation efforts, there is a lot more that needs to be done to evaluate SMHM and its habitat to ensure its continued survival. The objective of this research proposal is to measure the SMHM population and its habitat, in order to evaluate the probability of its continued survival. The results of this research will be forwarded to the appropriate agency for further conservation efforts of SMHM in the San Francisco Bay.

As natural resources experience an increased impact by human activities, the list of endangered species of flora and fauna expands. This highlights the importance of bringing all aspects of conservation efforts to the forefront. These efforts are often restricted by funding and logistical components and so prioritization must take place to ensure the preservation of critical populations and habitats, rather than a species in its entire historical range. It is critical to preserve genetic diversity which, in turn, allows for the preservation of the ecological and evolutionary aspects that are required for a species to continue to exist.

Captive breeding and reintroduction, translocations, population size estimates, inbreeding depression and avoidance, disease resistance, hybridization between introduced and native species, climate change and adaptation.

Bill Freedmen, author of “Endangered Species—Human Causes Of Extinction and Endangerment” notes, “scientists approximate that present extinction rates are 1,000 to 10,000 times higher than the average natural extinction rate.” These distressing numbers should be acted upon to save the endangered species and avoid the catastrophic change to this planet if these species were to become extinct. In order to produce change, people need to recognize that habitat loss, climate change, and poaching are all factors in why our animal species are going extinct.