The Osprey Tracking one of the Chesapeake Bays
The Osprey: Tracking one of the Chesapeake Bay’s Majestic Migratory Shorebirds
THE 411 ON OSPREYS
Basic Information about the Osprey (Pandion haliaetus) • One of North America's largest birds of prey, the Osprey is a magnificent fish-eating hawk with a white-crested head, yellow eyes, a white underside, and a dark brown back. • The species, once gravely imperiled, has undergone a tremendous resurgence and occurs virtually worldwide, near coastlines, lakes, and rivers, where the birds hunt for their food. Source: http: //birds. audubon. org/species/osprey
Appearance Description Appearance of the Osprey • Appearance Weight ranges from 3 -4 pounds Wingspan of up to six feet Length is approximately 2 feet Plumage Color: dark brown on top and white underneath – Black sharply curved beak – White crown and head with a dark band extending back from behind its yellow eyes – – Source: http: //birds. audubon. org/species/osprey
Appearance Description Appearance of the Osprey • Appearance – Females are generally larger than the males and normally have a speckled brown necklace across upper chest area – Possess 4 pale toes with long, black talons – Barbed pads on their feet and a reversible outer toe help the osprey hold on to slippery fish Source: http: //birds. audubon. org/species/osprey
Range Map Legend Range Distribution of the Osprey • Found on every continent except Antarctica, the Osprey, or fish hawk, is among the most widely distributed raptors in the world. • In North America, it breeds from Alaska through Canada, southward along both coasts to Mexico and the West Indies, and in scattered inland locations, such as around the Great Lakes. • The birds mainly winter south of the United States, in Central and South America to central Chile and the northern coast of Argentina, but a few may winter as far north as southern Canada. Source: http: //birds. audubon. org/species/osprey Key for map is found at http: //birds. audubon. org/sites/default/files/photos/kaufma n_range_map_key. jpg
Habitats of the Osprey • Ospreys live along seacoasts, inland bays [like thee Chesapeake Bay], freshwater reservoirs, and large rivers and lakes, wherever large concentrations of fish are available. • They breed in a variety of shallow water habitats, including boreal forest ponds, desert salt-flat lagoons, mangrove and salt marsh islands, and temperate and tropical lakes and seacoasts. • They winter in both coastal and interior areas with shallow, clear water nearby.
Feeding Habits of the Osprey • Ospreys subsist almost entirely on live fish. • Prey consists of species that typically school at the water's surface or swim in the shallows. • Birds hunt on the wing, often hovering over the water when they spot a fish, and then plunging into the water feet first to grab it with their powerful talons. • When an Osprey emerges from the water with its catch, it uses its feet to turn the fish headfirst to reduce aerodynamic drag. • The bird then flies off with the fish to an elevated perch, often near the nest, and eats it. • Watch the You. Tube video called “Osprey---the ultimate fisher” at https: //www. youtube. com/watch? v=n. A 3 Lt. Xn. NIto
Breeding Habits/Reproduction of the Osprey • Ospreys can reach sexual maturity in three years. • At this time, males generally select nesting sites, which are typically close to water, open to the sky, and safe from predators. • Locations include treetops, cliffs, large shoreline boulders, and even the ground on small, inaccessible islands. • The birds also readily use manmade structures, such as utility poles, channel markers, duck-hunting blinds, and platforms designed especially for Ospreys. http: //ospreycamerablog. files. wordpress. com/ 2013/04/osprey-eggs. png Source: http: //birds. audubon. org/species/osprey
Breeding Habits/Reproduction of the Osprey • Nests are large, built of sticks, and lined with bark, grass, algae, and sometimes, plastic bags. • A clutch usually consists of three eggs, which are incubated mostly by the female. • Males occasionally pitch in, but they mainly provide their mates with food during the 38 -day incubation period. • Females then care for the brood, and males continue to provide food. • Offspring fledge when they are about 50 to 55 days old, but depend on their parents for nourishment for another 8 weeks. Source: http: //birds. audubon. org/species/osprey
Migration Patterns of the Osprey • Most Ospreys breeding in North America are migratory, except for permanent resident populations in southern Florida, the Caribbean, the Gulf Coast, and Baja, Mexico. • American and Canadian breeders, which winter in Central and South America, begin their southbound journeys in August. • They return north between late February and April. Migrants travel alone. • An Osprey nesting in central Quebec and wintering in southern Brazil may cover more than 120, 000 miles during its lifetime. Source: http: //birds. audubon. org/species/osprey
Why do birds migrate? • Birds migrate to move from areas of low or decreasing resources to areas of high or increasing resources. The two primary resources being sought are food and nesting locations. • Birds that nest in the northern hemisphere tend to migrate northward in the spring to take advantage of burgeoning insect populations, budding plants and an abundance of nesting locations. http: //www. birds. cornell. edu/All. About. Birds/studying/migration/
Why do birds migrate? • As winter approaches, and the availability of insects and other food resources drops, the birds move south again. • Escaping the cold is a motivating factor but many species, including hummingbirds, can withstand freezing temperatures as long as an adequate supply of food is available. http: //www. birds. cornell. edu/All. About. Birds/studying/migration/
Types of Migration • Short-distance migrants: May move only a short distance, as from higher to lower elevations on a mountainside. • Medium-distance migrants: Some species may cover distances that span from one to several states. Long-distance migrants: Birds that typically have ranges that extend from the United States and Canada in the summer to Mexico and further south in the winter. http: //www. birds. cornell. edu/All. About. Birds/studying/migration/
What triggers migration? • The mechanisms initiating migratory behavior vary and are not always completely understood. • Migration can be triggered by a combination of changes in day length, lower temperatures, changes in food supplies, and genetic predisposition. • Different species of birds and even segments of the population within the same species may follow different migratory patterns. http: //www. birds. cornell. edu/All. About. Birds/studying/migration/
Flyways of the World for Migratory Birds Ribbons of color on the map represent migratory paths, called flyways, of birds that travel thousands of miles twice each year.
The Atlantic Flyway • The Chesapeake Bay watershed lies within the Atlantic Flyway and is a migratory stop for many birds to rest and refuel during travel. • For some birds, the Chesapeake Bay is their winter destination. About 1 million swans, geese and ducks winter on the Bay, roughly one third of all waterfowl wintering along the Atlantic Coast. • Many migratory songbirds, shorebirds and raptors rest and refuel in Baltimore City during their spring and fall migrations. They love city parks for this reason. • Still others winter south and return Source: http: //www. fws. gov/chesapeakebay/migbird. html to the Chesapeake Bay watershed each spring to breed.
http: //www. osprey-watch. org/learn-about-osprey/build-an-osprey-nest/ BUILD AN OSPREY NEST
Conservation Status of the Osprey • Global Population: 460, 000 • Continental Population: 211, 500 • Overall population trend: increasing numbers • Osprey numbers are on the rise after global numbers plummeted from the 1950 s through the 1970 s. • In the United States, declines were most severe along the North Atlantic coast and in the Great Lakes region. Source: http: //birds. audubon. org/species/osprey • But by the year 2000, most North American populations had rebounded to nearhistorical abundance levels, with birds reoccupying former habitats and moving into new areas. • Some states, however, have not experienced such successful turnarounds, and still list the species as threatened or endangered.
Threats to the Conservation of the Osprey • Poisoning by DDT and other related pesticides caused eggshell thinning and widespread breeding failures, leading to a sharp drop in Osprey populations. • After DDT use was banned in the United States in 1972, the species rapidly rallied. • Risks continue to be posed in countries where Ospreys breed and pesticides are not regulated. Source: http: //birds. audubon. org/species/osprey http: //www. cals. ncsu. edu/course/ent 425/text 19/convchem. html
Threats to the Conservation of the Osprey • The birds are also vulnerable to the destruction of nest sites by logging; the conversion of habitat into farmland; declines in water quality and fish populations; shooting; collisions with motor vehicles and stationary structures; and electrocution by power transmission lines and transformers. • In many areas, Ospreys have benefited from active management, including the erection of artificial nesting platforms, and the reintroduction of birds into areas where the species has been decimated. Source: http: //birds. audubon. org/species/osprey http: //www. osprey-watch. org/wpcontent/uploads/2013/10/nest 301_chicks-onpower-pole-nest. jpg
Threats to the Conservation of the Migratory Birds • As many as 80 million • SOLUTION: This problem songbirds are killed each can be minimized by year by collisions with plate placing silhouettes of glass windows. falcons on the outside of the plate glass windows. • Most die of skull fractures and internal injuries. • Falcons are natural predators on wild birds, • Birds see reflections of and will usually cause a trees, and fly directly into bird to veer away from the window, often at high window, thus avoiding a speeds. collision. http: //www. wbu. com/chipperwoods/photos/t hreats. htm
Plate Glass Windows http: //www. wbu. com/chipperwoods/photos/t hreats. htm
Threats to the Conservation of the Migratory Birds • As many as 5, 000 birds can be killed in one night at a single tower site. • Communication towers are particularly hazardous to birds that migrate at night. • Many species of birds migrate just above the treetops, and collide with towers and high wires. • On misty overcast nights, the lights on the towers disorient the birds, and as they fly around the towers, many are killed by collisions with the wires. http: //www. wbu. com/chipperwoods/photos/t hreats. htm
Communication Towers http: //www. wbu. com/chipperwoods/photos/threats. htm http: //en. wikipedia. org/wiki/Transmission_tower http: //www. dreamstime. com/royalty-free-stock-image-high-tension-powerimage 9186
Threats to the Conservation of the Migratory Birds • Nearly a million songbirds are killed each year by collisions with lighted tall buildings. • Once again, birds that migrate at night suffer the most. • Southern exposures present the greatest risk to birds coming north during the spring migration. • Northern faces of buildings are the greatest risk during fall migrations. • SOLUTION: Turn out lights in high rise buildings – like those in downtown Baltimore - during spring and fall migration. http: //www. wbu. com/chipperwoods/photos/t hreats. htm
Tall Buildings and Skyscrapers http: //denverinfill. com/blog/2008/10/new-downtown-denver-project-1501. html http: //lopressroom. com/viracon/four-seasons-hotel-and-private-residences-toronto-shinesviracon-glass http: //www. 123 rf. com/photo_3343546_tall-office-building-with-blue-glass-windows. html
Threats to the Conservation of the Migratory Birds • The continued loss of critical breeding and migratory stopover habitat to human development poses a devastating threat to wild bird populations. • Without suitable breeding habitat, birds cannot maintain their populations. • Without key migratory stopovers, birds cannot even reach their breeding grounds. • As human populations increase, this problem will likely worsen. http: //www. wbu. com/chipperwoods/photos/t hreats. htm
Threats to the Conservation of the Migratory Birds • SOLUTION: Thoughtful land use planning can go a long way toward identifying and conserving those habitats that are critical to birds and other forms of wildlife. Development that does occur can be planned to preserve some habitat areas.
Loss of Breeding Grounds http: //www. wbu. com/chipperwoods/photos/t hreats. htm
https: //www. youtube. com/watch? v=-Z 6 Rcx. M 8 Q 7 g OSPREY NESTS KEEP BLOCKING TRAFFIC CAMERAS VIDEO
http: //www. osprey-watch. org/learn-about-osprey/build-an-osprey-nest/ LET’S BUILD AN OSPREY NEST!
http: //www. cbf. org/ospreymap OSPREY TRACKING PROJECT
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