In August, the Light as a Feather committee members of the Greater Princeton branch of AYLUS (GPA) continued another Earth Team Volunteer Event at Plainsboro Preserve Education Center (80 Scotts Corner Road, East Windsor, NJ 08512).
Study skins are the standard method of preparation in Ornithology Collections, though skeletons, fluid-preparations, and spread wings are also commonplace. Non-skin preparations represent a growing proportion of collections as emerging museum technologies facilitate discovery (e.g., CT scanning, 3D photogrammetry, high resolution focus stacking). Additionally, tissues and symbionts are often collected at the time of preparation.
Study skins capture the outward appearance of an individual, preserving anatomical structures and plumage. Bird skins are prepared in a standard pose in order to provide a basic unit of comparison as well as to minimize storage footprint. Large, long-billed, or crested taxa may have slight variations on the classic cylindrical study skin shape, such as folded necks and legs, or heads turned to the side to consolidate fragile extremities or highlight diagnostic morphology.
Skin preparation follows these general steps:
Data gathering–measurements, weight and various external attributes (e.g., molt, colors, cloacal protuberance, brood patch) are recorded prior to skinning. Specimens may also be examined for ectoparasites at this stage.
Skinning – An incision is made, and the skin is worked away from the carcass, cutting at the knees, tail, humeri and posterior skull to extract the body core and retain the extremities with the skin. Internal data attributes are documented as they are encountered, such as fat deposition, body molt, bursa, skull ossification, gonad measurements and ova development.
Tissue collection–Tissues are typically taken at this stage. Detected internal symbionts may be harvested if desired.
Cleaning–The skin is cleaned of residual tissue, organs, blood, fat and oils. Especially fatty birds may require use of a scraping tool or fleshing wheel in addition to standard dissection instruments to fully strip grease from the skin. Washing or use of an absorbent are typically employed at this stage. Wet skins are dried with forced cold air or tumbled in absorbent.
Stuffing–The wings are tied in place internally and balled cotton is inserted into each eye orbit. The skin is stuffed with cotton or polyester batting by wrapping a dowel rod or shaped manikin. The bill and legs are tied for added stability.
Drying–Feathers are smoothed, and the skin is either wrapped or pinned in position on a board to dry.
GPA volunteers (8/15, 3 hrs): Ethan Xu, Charlotte Xu, Cassie Tammy Wang, Kathie Wang, Lina Yang, and Jessica Tong, excitedly started their second phase of study skins while making bird specimens with Mrs. Heidi Mass and Dr. Wang Qian at Plainsboro Preserve Environmental Education Center & New Jersey Audubon Society.
