During the dry season, this over-abundance of vegetation spurred an increase in wildfires. In the s, after rinderpest was eliminated through vaccinations, the wildebeest and buffalo returned. The ecosystem went from shrubbery to grasslands again, decreasing the amount of combustible vegetation, and the wildfires decreased.
The loss of pollinators could result in a decrease in seed and fruit production, leading ultimately to the extinction of many important plants.
Flying foxes, also known as fruit bats, are the only pollinators of some rainforest plants. They have been over-hunted in tropical forests with several species going extinct. One study noted that plant species, including eucalyptus and agave, rely on flying foxes to reproduce; in turn, these plants were responsible for producing valuable products. Bees pollinate over , species of plants, including most of the 87 crops that humans rely on for food, such as almonds, apples and cucumbers.
Over the last 20 years in the U. The rusty-patched bumble bee, another important pollinator and the first bee species to be put on the endangered list, now only occupies one percent of its former range.
Insect populations overall are declining due to climate change, habitat degradation, herbicides and pesticides. A review of insect studies found that most monitored species had decreased by about 45 percent.
And a German study found 75 percent fewer flying insects after just 27 years. As insect populations are reduced, the small animals, fish and birds that rely on them for food are being affected, and eventually the predators of fish and birds will feel the impacts as well. One entomologist who had studied insects in the rainforest in the s returned in to find an up to fold reduction.
Plankton, tiny plant and animal organisms that live in the ocean or fresh water, make up the foundation of the marine food chain. Phytoplankton are critical to the health of oceans and the planet because they consume carbon dioxide and produce oxygen during photosynthesis. In , researchers found that phytoplankton had decreased 40 percent globally since , and attributed the decline to rising sea surface temperatures. The scientists speculated that the warming surface waters did not mix well with the cooler, deeper waters rich in nutrients that phytoplankton need.
In addition, zooplankton are very sensitive to slight changes in the amount of oxygen in the ocean, and may be unable to adapt as areas of low oxygen expand due to climate change. The quantity and quality of plankton also affects the nutrition of other creatures further up the food chain.
In the Mediterranean Sea, the biomass of sardines and anchovies declined by one-third in just ten years. Changes in plankton quality could be a result of water temperature, pollution or lack of nutrients, but scientists are not exactly sure why the plankton makeup in some places is changing.
If it is due to global warming and pollution, some say the situation could worsen. A different community composition of phytoplankton could change the food web structure, but Dyhrman is not really worried about the total collapse of fisheries. What will the architecture of that ecosystem look like in the future? More than a quarter of prescription medications contain chemicals that were discovered through plants or animals. Penicillin was derived from a fungus. One molecule from a rare marine bacterium could be the basis of a new way to treat to melanoma.
Scientists have so far identified about 1. Twenty-five percent of Western medicines are derived from the rainforest. Photo: Tristan Schmurr. Who knows what substances or capabilities some of these species might possess that could help treat diseases and make human lives easier?
According to a study for the U. Already, a number of industries have been economically impacted by species loss. Atlantic cod in the waters off of Newfoundland formed the basis of the local economy since the 15 th century — until overfishing the cod destroyed the livelihoods of local fishermen. Extinction is hard to see. Past generations would regard what we see as natural today as terribly damaged, and what we see as damaged today, our children will view as natural.
Wooddell believes the most important thing one can do is to put pressure on Congress and elected leaders to create land management, pollution and other sustainable policies that will protect biodiversity and the environment. Employees in the News. Emergency Management. Survey Manual. Although extinctions occur naturally, the current rate of plant and animal extinctions is much higher than the natural or historical rates.
Habitat loss is the primary cause of higher extinction rates. Other causes include habitat changes, over-exploitation of wildlife for commercial purposes, the introduction of harmful nonnative species, pollution, and the spread of diseases.
A deadly fungal pathogen, Batrachochytrium salamandrivorans Bsal that affects amphibian skin was discovered during a die-off of European fire salamanders Salamandra salamandra in This pathogen has the potential to worsen already severe worldwide amphibian declines.
Bsal is a close relative to another fungal disease known as Greater sage-grouse Centrocercus urophasiunus, hereafter sage-grouse are broadly distributed, occupy a diversity of sagebrush habitats, and face multiple threats. As a result of these threats, sage-grouse populations are declining and are now absent from almost one-half of their estimated range prior to Euro-American settlement. The risks to White-nose syndrome WNS is a devastating disease that has killed millions of hibernating bats since it first appeared in New York in and has spread at an alarming rate from the northeastern to the central United States and Canada.
The disease is named for the white fungus Geomyces destructans that infects the skin of the muzzle, ears, and The western yellow-billed cuckoo, once common along the streams and rivers of the American West, is now a candidate for protection under the Endangered Species Act.
Most of the remaining breeding pairs are found in Arizona, California, and New Mexico. Research to understand the cuckoos' habitat needs by U.
Lead in its various forms has been used for thousands of years, originally in cooking utensils and glazes and more recently in many industrial and commercial applications. However, lead is a potent, potentially deadly toxin that damages many organs in the body and can affect all animals, including humans.
By the mid s, lead had been removed The Colorado River Basin supports one of the most distinctive fish communities in North America, including the federally endangered humpback chub Gila cypha. One of only six remaining populations of this fish is found in Grand Canyon, Arizona. Geological Survey scientists and their cooperators are responsible for monitoring the Grand Canyon Scientists at the USGS National Wildlife Health Center NWHC , in collaboration with colleagues at other federal agencies and the University of Wisconsin, are developing and testing vaccines that can be used to protect black-footed ferrets and prairie dogs against plague.
The black-footed ferret is commonly regarded as the most endangered mammal Intensive management of the Missouri and Mississippi Rivers has resulted in dramatic physical changes to these rivers. These changes have been implicated as causative agents in the decline of pallid sturgeon. The pallid sturgeon, federally listed as endangered, is endemic to the turbid waters of the Missouri River and the Lower Mississippi River Most of the 57 or so honeycreeper species are extinct, and the palila is Building a river setback levee to reduce the risk of flood for a community may also help endangered fish species to thrive, according to the results of a novel computer model reported by the U.
Geological Survey. BOZEMAN — Pallid sturgeon come from a genetic line that has lived on this planet for tens of millions of years; yet it has been decades since anyone has documented any of the enormous fish successfully producing young that survive to adulthood in the upper Missouri River basin. For the first time in nearly 50 years, a population of a nearly extinct frog has been rediscovered in the San Bernardino National Forest's San Jacinto Wilderness.
Researchers from the U. Geological Survey USGS have discovered a population of the endangered desert pupfish Cyprinodon macularius in constructed ponds along the southeastern shore of the Salton Sea, in south-central California. A highly endangered native Hawaiian bird species has taken a small but significant step back from the brink of extinction.
USGS biologists monitoring 14 captive-reared puaiohi released into the wild earlier this year by The Peregrine Fund say the birds are nesting and have already fledged four young. Pima pineapple cactus and vegetative offshoot, commonly called a pup, in the Altar Valley of south-central Arizona November A green and black endangered Sonoran tiger salamander Ambystoma mavortium stebbinsi on a tree branch.
Malaria transmission is tied closely to the effects of temperature on development of malarial parasites within their mosquito. USGS biologists are leading the monitoring and reintroduction effort of the Southern California mountain yellow-legged frog -- federally listed as endangered with only wild adults remaining in the mountains surrounding Los Angeles County.
Hunting and Fishing Many animals are over-hunted because their meat, fur and other parts are very valuable. Exotic Species When animals or plants arrive into a new habitat from a foreign place they sometimes introduce diseases that the native species can't fight. Endangered and Threatened Species. Animal Behavior. See also:.
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