The Implications Of Density Dependence

The macroinvertebrates graph (figure 2) represents the diversity of species inhabiting the Baldwin Swamp. In 2009 the Baldwin swamp was flourishing with a large diversity of species. A total of 33 macroinvertebrates, 8 species were recorded. At this time the baldwin swamp was healthy, abundant in life and the ecosystem and food webs were unaffected by the floods. Whereas 3 weeks after the floods swept through there were little to no range of species of macroinvertebrates. There were a recorded amount of 2 Damselfly Nymph and 1 waterboat man. A theory to why these two

Florida has more introduced species of reptiles and amphibians in the wild than anywhere else in the world, causing the native populations to become unbalanced (University of Florida, 2012).

The wetlands are an amazing part of the pinelands. They prevent pollution from entering the lakes as well as preventing floods. This is a major part of the safety of the Pine Barrens. This is where the endangered Pine Barrens tree frog lives. On a clear night you can hear these frogs a mile away. They hang out on reeds and trees near the water. This forest is home to many other animals. For instance, there are cranes, water snake, turtles, salamanders, small pickerel and bass, and other frogs like spring peepers. The water snakes are usually mistaken for poisonous water moccasins, which do not live in New Jersey. Wetlands are usually near lake edges, stream edges, or bogs and swamps.

The Northern Correboree Frog is an endangered species that is restricted to montane, subalpine woodlands, grassland and heathland 1,000 metres above sea level. The estimated amount of Northern Correboree Frogs is 1000-5000. One of the reasons why the Northern Correboree Frog is endangered is because of climate change. Climate change affects the Northern Correboree Frog because it was predicted that its population would decrease in winter and spring precipitation because, this would make one of the popular breeding habitats (edges of bog pools) very saturated and dry, which makes it hard for the frogs to breed.

Overall for this change project, we have learned that the population of frogs has been decreasing all over the world. There are many factors that decrease their population like agriculture, invasive species, and the population of humans. Specifically, in California, only 40% of the historical sites in the Northwest area have Foothill Yellow-Legged Frogs, and this has the highest percentage out of all of California. These frogs are indicators for the environment, meaning they can determine if the area around them has changed dramatically due to their permeable skin. For our service project, we removed invasive plants like the Himalayan Blackberries and dug creek beds for the frogs. From this, we were able to improve the levelness of the area

Known in the scientific community as Bufo marinus, cane toads were introduced to Australia in the mid-1900’s t rate from their native home of South America. Sugarcane crops were at risk of destruction from the infestation of beetles, and these species were brought in to help counter the negative effect that the beetles were having on farms. These amphibians have the ability to grow up to 4.4 pounds, and were soon doing more harm than good. Not only were the cane toads eating the beetles that they were meant to, but they also started including native insect-eaters in their diets (Roach). This new addition to their food source helped the toads to thrive and expand their habitat region.

Many sources say that the initial spread of this invasive species began at the end of the 1800's when bullfrogs were shipped to California to fill hungry loggers appetite for frog legs. The frogs competed with the other native species with the supply of natural resources while also consuming and exploiting the native amphibian species as well. Worldwide Rana catesbeiana has driven over one-hundred native species of frogs to extinction (Save The Frogs! et al. 2013). This is a huge impact on amphibian wildlife worldwide because there are about 4,800 species of frogs. Over the past hundred years the bullfrog has wiped out over 2% of the world's species of frogs. Studies have shown one of the reasons bullfrogs will cripple Arizonian ecosystems and the native amphibian species directly is because a female bullfrog’s physiology

The issue I will be raising is one that might not be familiar to all who reside in California and that is primarily focused around the fragmentation and overall mutilation of areas that keep and protect the species Rana Draytonii, otherwise known as the California Red-legged Frog. One of the reasons I raise this issue, is because most importantly “these frogs were named the official state amphibian of California via AB 2364” (Patrick McGreevy.). An even greater reason to discuss this dilemma is because they are limited in their size around the Southernmost California residences, whereas they had previously occupied approximately “70% of its former habitat” according to environmentalists (Campbell.). My goal is to highlight their ecological value to the state and how the California red-legged frog’s value is more significant than the fragmentation and intrusion taking place. These red-legged frogs are currently listed as endangered, but they are vulnerable to human intrusion by means of erecting buildings, projects for road construction, introduction of a non-native species along with habitat fragmentation in areas near where they might usually reside such as near the south Mendocino County and along southern California with populations extending to the Santa Rosa Plateau (Hammerson, Geoffrey). The California red-legged frog has an intrinsic link to

Different aquatic invertebrates live in different micro habitats (smaller habitats) at Lake Tonetta. Some live on the surface of the water. Others live in the bottom of the lake, or deep within the sediments at the bottom of the lake. The water pH is important because they only can live in a specific pH 6.5-7.5.When we visit the lake our group checked the biodiversity (The variety of plants and animal species in an environment)of Lake Tonetta by counting the aquatic invertebrates in a sample obtained using dip nets and bottom scrapers. During our trip, we found beetles, snails, worms ,

Unfortunately, freshwater snails like many other river species across North America are threatened. The abundance and variety of snails have dramatically declined over the last 80 years, especially those species that inhabit streams and rivers. Approximately 60 species of freshwater snails are presumed extinct, 20 are on the federal endangered or threatened species list, and another 290 species are of conservation concern nationwide. The decline of freshwater snails began in the early twentieth century. Dam construction and other channel modifications, siltation, and industrial and agricultural pollution have all degraded the river habitats on which most species depend. As a result, the species richness and the abundance of freshwater snails have declined dramatically. This decline has been especially pronounced in the Southeastern United States where these animals are most diverse. The continued loss and decline of freshwater snails and other river species are testament to the fact that despite significant water-quality improvements made in the last 25 years, much work remains if we are to halt species

This species habitat is the longleaf pine-wiregrass flatwoods. The adult salamanders eat earthworms, insects, and are likely to eat other invertebrates as well. The larvae eat a variety of aquatic invertebrates, especially crustaceans. The Flatwood Salamander’s population is roughly several thousand, and is decreasing. Part of the community that the salamanders live in consists of decaying logs, vegetation, earthworms, and insects. Part of the ecosystem that they live in consists of decaying logs, vegetation, earthworms, insects, crayfish burrows, forest fires, and shallow ponds.

The bullfrog, Lithobates catesbeianus (Shaw 1802), is a common aquaculture species that has become a dangerous invasive species. Considering that this North American anuran involve a great risk to native communities, its invasion is a mayor threat to biodiversity at the Neotropic. The invasion of this species is associated with different continental aquatic systems, but it displays a preference to the permanent ponds and water reservoirs. In Uruguay, three bullfrog populations were detected so far, two of which have failed to establish (a situation that seems to have happened in several cases), but one persisted and is expanding in Aceguá, Cerro Largo. Although local authorities are concerned about this invasion, no control action was implemented

Density is the first section that we learned about urbanism. Density is similar to the same density of science. How much stuff or matter within an amount of space. So we had to design a plan and also a model of what do we feel density is. To the following page I showed you my design of triangles and how they are closed and clustered together with different size and heights.

The Mississippi gopher frog (Lithobates sevosus) was registered as an endangered species by the state of Mississippi in 1992. Later, this rare species of true frog was also listed as species that are in danger of extinction by the U.S. fish and wildlife service. Their primary objective of listing this as an endangered species is to identify, protect and restore their population. An endangered species is classify as a species of animal or plant that is at risk of disappearing. Mississippi gopher frog is categorized as a critically endangered (CR) species by the International Union for Conservation of Nature (IUCN). Critically endangered species are the species that are facing a very high risk of going extinct in the

In addition to the conservation benefits of recognizing that metapopulations have spatial structure, a number of important conservation risks arise when conservationists do not account for the various potential spatial structures of metapopulations. One of the risks of assuming homogenous spatial structure is that the models will produce falsely high numbers, as the actual population violates the assumptions of the model. Wootton and Bell (1992) highlight the importance of addressing spatial structures in their model of Peregrine Falcon populations, as the census data alone would predict a falsely healthy population. Additionally, management plans in populations might be terminated prematurely if conservationists do not understand and account for the dynamics of source and sink metapopulations, which may have fluctuating levels of colonization and extinction rates that are normal for the dynamics of the population (Wootton and Bell 1992). Kauffman et al. (2004) echo this finding, as they emphasize the importance of understanding habitat-specific demographic data instead of an overall population count alone, which might carry the assumption of homogenous spatial structure and lead to a misdiagnosis of a population.