Wednesday, May 28, 2014

Tree Swallow

Tree Swallow
 The tree swallow is a North American swallow. They nest through out Canada and the northern United states and migrate down to the extreme southern US, Mexico, Central America and the Caribbean for the winter. They typically do not migrate as far south as other swallows because they eat more seeds and plant material than other swallows so they can survive in cooler climates where there are fewer insects.
Tree Swallow
 The tree swallow gets its name because it is a cavity nester and it is often found nesting in tree cavities. Tree swallows will also nest in nesting boxes that are placed in the right type of habitat. They prefer open habitats, such as fields and marshes, where they can catch their prey in flight. They also like to nest close to water because more flying insects are found around the water, due to the fact that the larva of many flying insects are aquatic.
Tree Swallow
 Like most swallows the primary diet of the tree swallow consists of insects. They hunt from dusk to dawn, typically flying close to the ground and catching their prey in flight. This bird was hunting for nesting materials when I photographed it.

Tuesday, May 20, 2014

Snowy Owl

Snowy Owl
 The snowy owl is a raptor of the northern tundra. They are circumpolar, nesting in northern portions of Alaska, Canada, Greenland, Europe and Asia. During the winter many of the adult snowy owls will stay on their nesting territory however many young birds may head south to southern Canada, the northern US, and central portions of Europe and Asia. They are the largest owl species, by weight, in North America and one of the largest in Europe and Asia.
Snowy Owl Female
Young birds can be identified by their black barring. The barring is usually darker on the females then on the males. As they age the barring fades until adult males are almost pure white. Hedwig, from harry Potter fame is actually a series of male snowy owls. Females often retain some of the barring even as adults. Since some males are darker then normal and some female lighter it is best to use the size of the bib under the head to determine between the sexes. This bird has a small bib so it is most likely female. The other owl  in these photos has a bib that extends half way down its chest so it is probably a male.
Snowy Owl in Flight
Snowy owls are more diurnal then most owls.It makes sense that they would have to be active during daytime hours during the nesting season, which runs from may through September. During the summer daylight can stretch to over 20 hours per day. Birds that stay on the nesting territory during the winter would have to switch to nocturnal hunting because of lack of daylight during the winter. The primary prey of the snowy owl are lemmings. They will also eat other small mammals as well as ptarmigan and water fowl. 
Snowy Owl Landing
Occasionally there are mass eruptions of snowy owls down into Europe, Asia, or the United States. These typically occur because of a lack of food in their tundra territories. this lack of food can be caused by a bad year for the prey species, such as a decline in the lemming population due to disease, or it can be caused by a particularly good breeding season. as a ground nesting bird snowy owls can lay up to 11 eggs in a clutch. most years a snowy pair can not support that many chicks and some do not make it. On a good year where there is plenty of prey during the breeding season more chicks survive and when it comes time for them to go out on their own in the winter many head south to find food. This past winter was a huge snowy eruption in the US. Snowies were seen all the way down in Florida. Most of the snowies that I spotted were immature birds which suggests that it was a good breeding year for snowies. Unfortunately many of the snowies that came south will never make it back.

Wednesday, May 14, 2014

Rowe Sanctuary

 Crane Blind
At the beginning of April I decided to take a short trip down to Nebraska to see the sandhill cranes. I had already been offered a job but since it took a while for the background check, drug test and all of the paper work to go through I decided it was the perfect time to head down to the Rowe Sanctuary. It had been many years since I last visited the sanctuary, I was still shooting film at the time, and typically the timing never seemed to work out. Either we were vacationing down south in late winter or we were heading to Yellowstone in May, either way it would be difficult to get away so close to another vacation. Since I was not starting work for another week I decided it would be a perfect time to go. 
Sandhill Cranes Dancing
The Rowe Sanctuary is an Audubon sanctuary located in central Nebraska. It consists of 1900 acres of river channel, wet meadows and agricultural land along the Platte River. It is named for Lillian Annette Rowe who financed teh initial purchase of 782 acres back in 1974 to help protect the habitat for migrating cranes.
Whooping Cranes in Flight
 It is necessary to protect this part of the Platte River because it is the main resting spot for cranes migrating back north across the central flyway. Each year approximately 600,000 or more cranes stop at the Platte between mid February and mid April. This includes about 80% of the worlds population of lesser sandhill cranes. It also includes a good number of greater sandhill cranes and many other birds. The weekend I was there we saw a pair of endangered whooping cranes mixed in with the sandhills.
Cranes At Sunset
The reason why they stop at this location is because the Platte is a shallow river with many sandbars. During the day the cranes venture through the bordering fields eating any left over grains. Since cranes do not have feet that allow them to perch in trees they spend the night standing in the shallow water of the Platte. The shallow waters act as an alarm to let them know if an terrestrial predators may be around. Each morning the cranes rise up from the river giving visitors a spectacular show only to return each night for an encore.

Wednesday, May 7, 2014


 Peregrine Falcon
The peregrine falcon is the quickest animal in the world. Although they typically fly at speeds around around 40 - 55 MPH, which is slower then many birds and several mammals, they can hit speeds in excess of 200 MPH when hunting. Peregrines are bird eaters that frequently hunt by flying higher then other birds, over .6 miles and then dropping down on their prey in a dive called a stoop. In their stoop they can hit speed over 200 MPH with the fastest speed ever measured hitting 242 MPH. The peregrine has special adaptations that help it to fly at high speeds. The pointed shape of their wings makes them very aerodynamic. The also have posts in their nostrils, called nare baffles, that help to equalize the extreme air pressure associated with diving at these high speeds.    
Peregrine Falcon
 Peregrines are a world wide species that is found on every continent except Antarctica. The word peregrine means "wanderer" and they have earned this name because peregrines that nest in the tundra will often migrate over 7,500 miles to winter in South America or southern Asia. Peregrines living in more temperate climates typically stay on territory all year long, particularly the males. Their preferred habitat is areas around rocky cliffs where they nest. The nest is a depression called a scrape. The scrape is made by the female, who uses her talon to cut a depression on a cliff ledge about 2 " deep.
Peregrine Falcon
In the 1950's and 60's the Peregrine falcons population fell to disastrous levels. Peregrines, along with numerous other species had suffered from DDT poisoning. DDT was a widely used insecticide that was passed up to the peregrine through insect eating prey birds. DDT did not affect the adult bird but it made their egg shells very thin, so that most eggs broke during incubation. Very few peregrines hatched and as the adults died through more natural means the population began to plummet. By the time that DDT was banned in the US, in 1972 peregrines had been extirpated from most of the eastern half of North America and were placed on the Endangered Species List. In the 1980's several groups, including the Peregrine Fund in the Eastern US, and the Midwest Peregrine Foundation in the middle of the US, began releasing young peregrines back into the wild. The eggs from these birds came from falconers and the young were placed in hack boxes until they fledged. Many hack boxes were located on tall building in cities and as the peregrine population began to rebound many were replaced with nest boxes. These additional nest boxes were placed on Buildings, bridges, smoke stacks and other man made structures and it provided the peregrines more nesting habitat in areas where their are not a lot of cliffs. The pigeon population in the cities also helped, provided the peregrines with abundant prey. The peregrine was taken off the Endangered Species List in 1999 and today they are thriving in many areas.