Ornithology – is a branch of zoology that concerns the study of birds.

Gray Catbird (Dumetella carolinensis) in Sapsucker Woods at the Cornell Lab of Ornithology near Ithaca, New York. Nikon D700/80-400VR, 1/250s, f/8, ISO 800, EV 0, 400mm focal length.
The science of ornithology is unlike most disciplines. Amateurs called Birders help scientists in location, breeding and population studies. Bird watching accounts for millions of dollars in sales of binoculars, spotting scopes, camera equipment and outdoor clothing each year. People have life lists which span decades and mine got a little shorter when I spotted and photographed the Gray Catbird you see above.

American Goldfinch (Spinus tristis) at the thistle seed feeder outside the Imogene Powers Johnson Visitor Center for Birds and Biodiversity at the Cornell Lab of Ornithology near Ithaca, New York. Nikon D700/80-400VR, 1/160s, f/6.3, ISO 200, EV 0, 400mm focal length.
The Cornell Lab of Ornithology located north of Ithaca, New York is not open to the public. The Lab does house the Imogene Powers Johnson Visitor Center for Birds and Biodiversity and is surrounded by Sapsucker Woods. Both of which are open to the public. The visitor center is a birders dream with interactive kiosks to explore every aspect of bird identification. A sound lab for bird songs, computer stations, theaters, library and observation locations. A popular bird feeding station had people watching American Goldfinches, Blue Jays, Titmouse, chickadees sparrows and blackbirds the whole time I was there.
Sapsucker Woods is a 230-acre sanctuary with trails, boardwalks, observation platforms, woods, wetlands, ponds and home to many species of animals, birds and other wildlife. About four miles of trails take you through some of the must diverse and rich environments I have ever seen in a private sanctuary.

A male Red-winged Blackbird (Agelaius phoeniceus) singing near the Owens Observation Platform in Sapsucker Woods at the Cornell Lab of Ornithology near Ithaca, New York. Nikon D700/80-400VR, 1/800s, f/14, ISO 800, EV 0, 400mm focal length.
The denizens of Sapsucker Woods were very used to people walking through their home. The observation platforms took me past nesting Canada geese and close enough for photos of small song birds in their natural environment.

Eastern Phoebe (Sayornis phoebe) in a tree near the Sherwood Observation Platform in Sapsucker Woods at the Cornell Lab of Ornithology near Ithaca, New York. Nikon D700/80-400VR, 1/125s, f/8, ISO 800, EV 0, 400mm focal length.
The boardwalks of Sapsucker Woods allows people to comfortably explore wetlands. The wetlands were full of Spring growth. Lush plants and bright flowers where in full bloom basking in the sunshine. Many birds where flying in and around the trees and vegetation feeding on insects.

Yellow-rumped Warbler (Dendroica coronata) near the Podell Boardwalk in Sapsucker Woods at the Cornell Lab of Ornithology near Ithaca, New York. Nikon D700/80-400VR, 1/400s, f/10, ISO 800, EV 0, 400mm focal length.
I watched this Yellow-rumped Warbler make many flights in his quest to gobble up as many insects as he could catch.