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Chapter 5 Biodiversity The number of species of animals and plants in a given area describes it biodiversity. What is the biggest threat to biodiversity? Habitat Loss Statistics from an Indiana Forest Area Deer Turtle Fox Raccoon Bats Owls A 2 4 3 7 3 2 B 0 2 0 0 2 0 C 6 6 0 6 8 0 D 6 0 4 3 11 1 What area would have the greatest biodiversity? What species has the highest average population size? What species is most likely to face extinction? If all four areas have the same temperature and precipitation and geology , which one would most likely have the smallest area? Reintroduction in Indiana? At 10,750 acres, Lake Monroe is the site of the state's bald eagle reintroduction program from 1985 - 1989. Although an eagle nest was found on the lake in 1988, it would to be another 3 years before an eaglet would hatch - the first from Indiana's reintroduction program and the first to hatch in the wild in Indiana since 1897. In 2008, yet another record number of eaglets hatched from yet another record number of nests in the state. Lake Monroe today is the birding and eagle-watching capital of Indiana, with year-round resident pairs of bald eagles. Habitat fragmentation most affects which group? Group A Large Predators Large Herbivores Migratory Animals Group B Small Predators Small Herbivores Non-Migratory Animals What are sources of acid precipitation? Sulfur dioxide from burning coal. Nitrogen oxides from car exhaust Fragile Eggs and DDT The potentially lethal impact of DDT on birds was first noted in the late 1950s when spraying to control the beetles that carry Dutch elm disease led to a slaughter of robins in Michigan and elsewhere. Researchers discovered that earthworms were accumulating the persistent pesticide and that the robins eating them were being poisoned. Other birds fell victim, too. Invasive Species Example in the Great Lakes States (Accidentally Introduced) Any native species of earthworms that may have lived in the region were destroyed when glacial ice sheets covered the Upper Midwest 11,000 to 14,000 years ago. Forests of the Great Lakes region developed without earthworms. All earthworms now in the region are exotic, and most are European. They continue to be transported through the dumping of unused fishing bait, and the transport of compost and mulch. Leaf litter decomposition in hardwood forests is controlled by fungi and bacteria. Decomposition is slower than accumulation of new litter, resulting in the formation of a thick, spongy forest floor that provides protection from predation and extremes in temperature and moisture to seeds. Earthworms remove the forest floor by eating it and by mixing it into the upper soil. As a result, it is difficult for plants and animals adapted to forest floor conditions to survive following earthworm invasion. Extinct Species Examples The Caribbean monk seal has joined a long and growing list of species that carry the "extinct" label. The seals were first sighted during Christopher Columbus' second voyage in 1494 and once numbered in excess of 250,000. But the creatures proved easy prey and were killed primarily for their blubber. The last confirmed sighting was in 1952. The dodo is perhaps the bestknown example of a species driven to extinction by human activity. Their numbers dwindled quickly after the arrival of Portuguese and Dutch sailors to the Indian Ocean island of Mauritius in the 1500s. Some of the flightless birds were hunted by humans, though competition with dogs, pigs and other animals introduced by settlers may have been the true cause of extinction, some scientists say. A Sad Story…. The last known individual of the passenger pigeon species was "Martha" (named after Martha Washington). She died at the Cincinnati Zoological Garden, and was donated to the Smithsonian Institution, where her body was once mounted in a display case with this notation: MARTHA Last of her species, died at 1 p.m., 1 September 1914, age 29, in the Cincinnati Zoological Garden. EXTINCT Habitat Degradation Includes… Water Pollution Land Pollution Air Pollution Ozone Layer Depletion The Nearer the Equator, the MORE species of plants and animals. Ocean Levels are Increasing. How could this affect biodiversity on islands? Why? Island size might decrease and with it a species biodiversity decrease. Island Size Biodiversity What is the biggest factor affecting biodiversity? AREA or available space! Which land area would protect biodiversity the best? Larger land areas are better in Conservation Biology