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Natural History Woodpeckers have been around for a long time: their fossil remains date back 25 million years and they’re widely distributed, with 45 species in the US and more than 200 worldwide. Nine species either live year-round in Pennsylvania or visit the state in winter. Once there were so many gray squirrels in Pennsylvania that they were considered nuisances by pioneering farmers. In fact, bounties were paid on 640,000 squirrels in 1749, and many more were doubtless taken for the table. Settlement and development of our state has changed the habitat, and squirrel numbers have decreased since the 18th century Natural History (cont.) Owl fossils found in Midwestern United States date back about 60 million years. Eight species of owls either live in Pennsylvania or visit the state in winter. Beaver fur is thick and considered valuable; untanned pelts brought four dollars each in the early 1800s, when the skins were used to make top hats and to trim clothes. By the end of the nineteenth century, uncontrolled trapping had eliminated beavers in Pennsylvania and other states, but today this aquatic furbearer is back. Ecosystems Forests Grasslands Grasshopper Sparrow, Eastern Meadowlark, Bobwhite Quail Fisher, Black Bear, Scarlet Tanager, Wild Turkey, Brown Creeper Ecosystems (cont). Specific Roles Wetlands Beaver, Snapping Turtle, Red Winged Blackbird, Bluebird, American Robin, Eastern Gray Squirrel, Urban and Suburban Chipping Sparrow, American Robin, Deer Mice, Cottontail Rabbit Specific Roles Goldfinch Each animal has a role or function within its habitat. This role is referred to as its ecological niche. A goldfinch lives in fields, eats seeds and in doing so helps disperse the plant species throughout the area. Of course the goldfinch itself may be a source of food for a hungry Cooper’s hawk. Cooper’s Hawk Examples of Species White-tailed Deer Gray Squirrel Bobcat Raccoon Eastern Cottontail Examples of Species (Cont’d) Eastern Towhee Blue Jay Northern Flicker Barred Owl Eastern Screech Owl How Habitats Can Be Improved For Specific Species Barn Owl Changing land use and agricultural practices have led to a decline in Barn Owl populations. Shifting from pasture to row crops and a loss of nesting sites are the most serious problems for this species, which also result in lower meadow vole populations. Increasing the meadow vole population by changing methods will likely result in growth of the Barn Owl population. Preservation of caves used by Indiana bats for hibernation presents an interesting challenge. Access to the caves should be restricted to prevent human disruption of the bats’ hibernation; but access restrictions such as doors or walls can block the caves’ airflow and raise the temperature inside, preventing the bats from hibernating as deeply and causing them to use their fat reserves more quickly. Such alterations in airflow can have a large impact. Indiana Bat Osprey In the early 1900s ospreys nested along the state’s rivers and streams, but habitat destruction and water pollution made these areas unsuitable. Osprey populations were further decimated through the effects of pesticides on their reproductive capabilities. Reviving their habitat and cleaning the water osprey population.