Specialization+&+Effects+of+endangered+on+other+systems

Back = Animal's Ability to Survive and Effects of Extinction =

Certain adaptations that an organism acquires may lead to specilization. Threatened, endanged, and extinct species effect both human and natural systems.
There are many factor that may influence a population's size. Food, habitat, mating, environmental characteristics and human caused selective pressures such as hunting and pollution can effect a population. The most important and influential of these factors currently is habitat destruction. Due to the growing number of people on our planet, ecosystems are being destroyed and replaced with residential and urban ares. Pollution also plays a role because improper disposal and treatment of waste. Air pollution can lead to inhabitable conditions within a region, such as acid rain, which makes lakes and streams "die" as a result of an unbalanced pH level. Hunting can also create an unhealthy dive in a population when it is unregulated. This can be seen by the Dodo's extinction to due to over hunting and exploitation. Natural causes such as food sources and ability to adapt leads to a species increase or decrease. If the raw needs or an organism are supplied by its environment, it will flourish. Inversely, if the needs of a species are not met by its environment, it will not be able to have success and ultimately will not reproduce as much because the environment cannot support as many organisms, thus leading to a decrease.
 * __Factors that Lead to a Species' Increase or Decrease__**

Management practices can influence a species both positively and negatively. For instance, one of the positive management practices are game laws limiting the size and number of organisms able to be caught or hunted. This allows for younger organisms of the same species to fully mature and have the operatunity to reproduce. Management practices can also influence a population negatively. For instance pest management decreases the number, or may completely wipe out a population. While this may be beneficial to us as humans, it negatively effects that species and can effect species closely dependent. For example the Bald Eagle's eggs being weak as a result of eating insects poisoned by DDT.
 * __Management Practices Influence Success of Species__**

**__Criteria Used by Scientists for Categorizing Organisms As Endangered Threatened or Extinct__** Scienctists rely on the criteria put forth by the World Conservaton Union (IUCN) to label a species as threatened, endangered or extinct. These criteria include things like population size, growth rate, avaliablitiy of resources, reproductive succes and environmental factors such as habitat. The first stage is a species being recgonised as threatened. Regulations and special attentions towards conservation are introduced. Once further threats to the species become evident and there is a further danger of extinction the species is classifyed as endangered and regognised by the US Endangered Species Act, which requires a plan to rehabilate the species. Once a species reaches a point where it can no longer naturally rehabilitate itself and exist without dying out, or if the species no longer exists it is considered extinct (IUCN). An algal bloom is when there is a dense accumulation of microscopic organisms (due to an overbundance of nutrients in the water). When there is an algal bloom, the microorganisms release toxic substances into the water. This depleats the oxygen in the water, poisons aquatic animals and waterfowl, and irritates the skin and respiratory tract of humans. In addition to harming the ecosystem and humans, it also harms the economy. Because algal blooms creates public hazards, such as recreational swimmers and boaters becomming trapped in the water, many tourists and locals who use the water may stop comming. This would causes the surrounding business to lose money. Also, fisherman are not able to catch as many fish, causing them to make less money. When algae is decreased or eliminated, this may also cause problems. Algae is one of the main sources of oxygen for the aquatic organsims in its ecosystem. When it is decreased or eliminated, the amount of oxygen in the ecosystem is also decreased, which could cause the organsims depending on this oxygen to die. Fish being included in these organisms, fisherman would catch less fish, increasing the prices for restaurants and citizens ("Red"). **__Natural Populations do not Remain Constant __**  Generally, over time a population will be regulated by both density-independent and density-dependent factors. It will stay fairly stable in its size, but these factors will cause it to be constantly altered. Some populations have regular boom and bust cycles, but most populations only fluctuate midly. A density- dependent factor is a population- limiting factor whose effects intensify as the population increases in size. A density-independent factor is a population-limiting factor whose intensity is unrelated to population density (Campbell 2001).
 * __Species' Increase, Decline, and Elimination Affects the Ecosystem/Humans/Economic Structures__**

__**Laws, Agreements, and National/ International Treaties**__ Endangered Species Act of 1973- determines which species are endangered and threatened, prohibits unauthorized taking, possession, sale, and transport of endangered species, give authority to take land for the conservation of listed species and using land and water conservation funds, authorizes the grants to give to states that establish and maintain active programs for endangered and threatened wildlife and plants, and is in charge of paying rewards to those who turn in people voilating this act ("Endangered Species"). Marine Mammal Protection Act- makes it illegal for any person who is under legal jurisdiction of the United States to kill, hunt, injure or harass any species of marine mammals. Also, the Marine Mammal Protection Act also states that it is illegal for anyone to import marine mammals or products made from them into the United States. Marine mammals protected under this Act include: dolphins, whales, seals, sea lions, sea otters, polar bears, manatees, dugongs and walruses ("Some"). The Convention on International Trade in Endangered Species of Wild Fauna and Flora **-** formed to help prevent the loss of wild animal and plant populations, which were being depleted in order to satisfy the demands for trade. It is an international treaty that gives protection for wild animal and plant species involved with international trade ("Some"). The International Convention on the Regulation of Whales- The purpose of the Convention is to help conserve whale stocks and maintain an orderly whaling industry ("A General"). The Convention for the Protection and Development of the Marine Environment of the Wider Caribbean Region- established to prevent, reduce and control pollution of the Convention area and to ensure good environmental management. The pollution includes that which is dumped into the water, released unintentionally into the water, and pollution from the air. Also, the convention will protect and preserve failing ecosystems and habitats of threatened and endangered species ("Convention").
 * __Management Strategies__**  The Analysis and Adaptive Management (AAM) Program made ways to help conservation of endangered and threatened species be successful. They had four main goals; to spread out the power and responsibilty of maintaining biodiversity, to use adaptative management, to help governmental conservation orginizations work with nongovernmental orgainzations, and to show the relationships between human health and conservation ("Doing"). Ecological Strategies, whose goal is to work with landowners, communities and agencies and do science-based natural resources planning, management, restoration and education, has conducted numerous rare species surveys in many types of ecosystems. They do plant, insect, and bird surveys (to make sure their numbers are staying healthy, and they help manage and restore habitats. They also take rare plant and butterfly surveys, and recommend changes in habitat management to landowners and other orginizations ("Endangered, Threatened").  



The World Association of Zoos and Aquariums (WAZA) and the World Conservation Union (IUCN) are currently working together in order to inform others about conservation. In 2005, they published "Building a Future for Wildlife: The World Zoo and Aquarium Conservation Strategy". This emphasises the need for collabrative conservation (such as zoos working together and other conservation organizations). Wildlife preserves take in endangered and threatened species and help their numbers reach a healthy point again by keeping them out of danger and giving them a good food supply. __**Influence of Wildlife Management in PA**__ Eagle- Pennsylvania’s bald eagle population numbers more than 40 nesting pairs – up from three in 1980 – because on the Game Commission’s bald eagle reintroduction program in the 1990s (Kosack). Bobcats- Pa's bobcat populations are being kept relatatively stable due to the bobcat management plan ("Game"). Elk- The Elk Management plan helped imporve the habitat of the elk in PA, and also helped them maintain a healthy population size (DeBerti 2006).
 * __Role of Zoos and Wildlife Preserves__**