This post was contributed by WOS member Annie Lindsay, lead author of a recent paper in North American Bird Bander about the air compressor system she describes here.
Bird banders take standard measurements on all birds they process as they build their datasets, some of which require banders to use their breath to blow gently to part a bird’s feathers. One of the most universal of these measurements is an inspection of the fat layer visible under the skin, which gives information about things like migratory readiness and refueling performance. Depending on the season, banders may also need to part feathers to check for breeding condition (whether the bird has a brood patch or cloacal protuberance), the level of skull development (which aids in ageing), and any sign of molt activity.
Banders around the world pride themselves on consistency, accuracy, and completeness in their data collection, and the ability to compare these measurements across geographic locations strengthens and enhances banding data. In fact, banders often calibrate their measurements when they visit other banding stations, gather for professional meetings or conferences, or attend banding workshops.
As spring migration in 2020 approached, many researchers cancelled their field seasons due to concern about the emerging global pandemic and uncertainty about how to prevent transmission of the COVID-19 virus between members of field crews. Research across the continent ground nearly to a halt as early indications suggested that this virus was spread by airborne transmission of infected droplets, making working even in small groups risky. Banders were particularly concerned about contributing to the rapid spread of the virus because of the necessity of blowing potentially germ-laden breath during the banding process, and many stations decided to suspend banding operations to slow the spread until a vaccine could be developed and herd immunity reached.
Powdermill Avian Research Center (PARC) was not an exception. Nestled in the Laurel Highlands of southwest Pennsylvania about an hour southeast of Pittsburgh, Powdermill is Carnegie Museum of Natural History’s environmental research center. Ornithologists at Powdermill have operated a year-round bird banding station since 1961, and the station has the distinction of being one of the oldest continuously-run, year-round banding operations on the continent. Although cancelling the spring 2020 season was the correct decision, it was particularly emotionally difficult because of the very recent passing of the founder of Powdermill’s banding station, Bob Leberman, and the uncertainty about how long the hiatus would be. Our volunteers, seasonal field techs, and visitors were put on pause until we could bring them back safely.
The museum quickly developed and implemented rigorous safety protocols, including masking, physical distancing, health screenings, and increased sanitization. Masking, of course, makes it impossible to use breath as part of the banding process. While the museum’s protocols brought us back into the banding lab, the last piece of the puzzle was figuring out how we could blow feathers without using our breath. We brainstormed several ideas, including an air bulb for cleaning keyboards and camera lenses, that we found did not produce a strong enough or steady enough puff, and determined that an air compressor system that controlled the flow rate would work well. Equipped with our new system, we were able to bring our summer field tech on board and open our nets on June 1, 2020, for a normal summer season, and we have successfully operated the station since!
The blower setup is simple and can be built with materials easily found in a hardware store. A long air hose connects a portable electric air compressor to a pneumatic foot pedal and an outlet nozzle, all with brass fittings connecting the components. We tested the air pressure output with several nozzles to perfect the force of air flow so that the air blowing on birds was exactly perfect to safely part feathers.
We shared our air compressor system’s specifications with other banders, who have implemented the system at their own stations. It has proved useful in complying with COVID protocols, but we’ve found that the system has utility beyond protection during the pandemic. Some banders have difficulty directing their breath or producing a big enough puff to adequately part feathers. Others have presbyopia, which is the inability to focus on close objects, and must hold birds at a distance beyond which most people’s breath has difficulty reaching the bird with enough force to part feathers. The previous solution was to attempt to part feathers by blowing through a straw, but many banders have found the air compressor to be a better solution. It has also proved to be an excellent tool during bird banding demonstrations to show visitors what we look for when we assess fat scores in migrating and resident birds. Other uses of the system might be to prevent spread of germs during the normal cold and flu seasons, or to spare fellow banders after a particularly garlicy meal!
Our banding crew easily adjusted to using the air compressor, and some prefer it to using their own breath! The system has become a permanent fixture for us, and it was incorporated into the building plans for the new banding lab facility currently under construction at Powdermill. The compressor will be housed in a separate room and the house will snake through the walls with outlet ports in both banding rooms.
Despite the setback of missing the 2020 spring migration season, that year held several highlights. I operated the station alone to collect data for a separate project, and although I had to release all birds unbanded except for my three focal species (it is nearly impossible to check all nets and process all captured birds within our protocol’s 40 minute net rounds without skilled help), every day held the opportunity to observe birds in the field and get fresh air. In May, I caught a tiny but stabby bird, my first in-the-hand Least Bittern (only the fifth in Powdermill’s dataset), and called PARC’s Avian Conservation Scientist, Luke DeGroote, to come outside to socially-distanced admire the bird. That fall, we caught and banded a Brewer’s Sparrow, the first ever record of that species in Pennsylvania. The bird stayed at Powdermill for a week, delighting birders with good views as it foraged with Chipping Sparrows and gained fat. A few weeks later, we caught a bilateral gynandromorph Rose-breasted Grosbeak, a bird that as half-mal and half-female, split down the middle. This was the fifth gynandromorph in Powdermill’s dataset and photos of the bird went viral!
PARC is mostly back to banding-as-usual with a full crew, visiting researchers, public visitors, and in-person banding workshops, but the air compressor blower system remains central to our operation, and its usefulness beyond COVID is a happy accident.