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A first-hand account of a bird banding activity on Olango Island. By Manolita Morales I have always been awed by birds’ ability to fly. As a child, I used to imagine birds as creatures with magical powers. Later, in my ecology classes, I learned to appreciate birds even more for their important role in the fabric of life. Their presence in an area indicates that area’s health and productivity.
Still, I yearned for a much closer acquaintance. The opportunity came with an invitation from friends in the Department of Environment and Natural Resources (DENR) to join them as an observer in a bird banding activity at the Olango Island Wildlife Sanctuary. Bird banding involves catching a bird, either a shorebird or a forest bird, placing a metal band (or ring) around one of its legs and then releasing the bird unharmed. Through this activity, the DENR gains information about migratory avian species that use places such as the Olango Island Wildlife Sanctuary either as a refueling or wintering site. These data, exchanged with scientists in countries like Japan, Malaysia and Australia, help complete the picture of bird migration in the East Asian Flyway, one of the most important bird flyways in the world, of which the Philippines is an important part. It was late afternoon when I arrived on Olango Island to join the bird banding party composed of the DENR staff (who arrived the day before to prepare for the activity), some observers from non-governmental organizations, and a few residents of Suba, Sabang, a community within the sanctuary. We had a quick meal, gathered our banding materials and supplies, and then trekked in the moonless night across the sanctuary to the site where the birds were to be captured. The selection of the trapping site was part of the preparatory activities of the DENR staff. This site was determined based on observations about the behavior, movements and actions of the birds. Working fast, we set up two bamboo poles and mist nets made of fine nylon strands invisible to the birds, taking care to ensure that the nets would not be submerged by the incoming tide and that the bottom of the net would not sag into the water when many birds were caught.
After the mist nets were installed, the bird banding party moved on to the base camp and banding station on a narrow strip of elevated land planted with coconut trees about 3 kilometers from where the mist nets were set up. Then, it was a matter of waiting for birds to be captured. Some of us killed time swapping stories, singing songs, and drinking coffee, while others, anticipating the long hard night’s work ahead, took the opportunity to catch much needed sleep. Suddenly, from a distance, came shrill cries of distress. That was the work call for all of us: birds have been captured in the nets. At the mist net site, we saw birds dangling helplessly, like insects trapped in a spider’s web. Every bird caught in the net was a unique extraction problem – it had to be handled correctly so it would not escape, or suffer stress, cramps or injuries, or at worst, get killed. Like people, birds reveal their character in crisis. Some birds fought to be free, but the more they moved, the more they got entangled in the net. Others pecked on the hands about to free them. There were those who were immobilized, perhaps because of fear, or maybe due to fatigue from their initial exertion. We collected and placed the birds in individual cotton bird bags. A DENR staff told me we were ready to return to base to “process” the birds. As onerous as “processing” initially sounded to me, it was a relief to find out that we were not about to make food out of the birds. Instead, armed with reference books and the DENR staff’s field knowledge, we identified the species of each bird. Then, using equipment like pliers, spring balance, rulers and a vernier caliper, we measured and recorded the birds’ morphometrics. “Morphometrics” simply means “body statistics”; it includes bill length (mm), total bill and head length (mm), wing length or span (mm), tarsus length (mm), weight (grams), age and sex. We put all these data into data sheets. Then the bird banding process began. First, we checked both legs, making sure that the bird was not already banded, then we checked the body for any color marks or flags. Noting that the bird did not have a band or bear any marks or flags, we chose an officially issued metal band appropriate for the species, checked the correct sequence of the band number engraved on the length of the tubing and the data sheet, placed the band in the correct “hole” of the pliers, and then around the bird’s leg, either below or above the tarsus joint, squeezing the pliers until the band closed properly. We examined each band to ensure that it fitted correctly, had closed properly and the inscription had not been defaced; bands, which had been badly fitted, or were of the wrong size for that species had to be removed. We entered the band number into the data sheet, recording lost, broken and damaged bands as well. Only then did we release the bird. We set the last bird free, as the early morning clouds were about to deliver the new day’s sun. It had been a full night, and one well spent. Having held a bird in my hand, having felt the beating of its heart, I have become more acutely aware that life is a common thread between humans and birds. You may find dead or injured birds in various situations. Birds washed onto beaches or killed on roads should be checked for bands. Birds temporarily stunned when they hit a window should be also be checked. If you encounter a bird color markings (bands or flags or others markings), please record the following details:
Correct handling means holding the bird around the body and never by the wings, legs or head. It takes a lot of practice, extra carefulness, patience and common sense to free birds from the mist nets unharmed. Color marking is the generic term and refers to the use of any colored mark or device, which permits identification of a bird in the field. The following terms are used to describe various forms of color marking: Color flagging involves attaching a small plastic color tab or flag to the leg of the bird. This mark looks like a color band with a trailing tab. Color flags are used to mark cohorts and have mainly been used for studies of migration. Flags are attached to the right leg. In large birds, in regions using a two-flag (color combination) system, the two flags are attached to the right tibia. In smaller shorebirds, one flag is attached to the right tibia, and one to the right tarsus. Color banding refers to the use of colored bands applied to the legs of birds. Each bird is marked with a unique combination of color bands. It is used extensively in breeding and behavioral studies where there is a need to identify a large number of individuals. Bird bands are made from a variety of metals and aluminum; the durability and color stability of color bands is dependent on the material used. The most suitable for use with shorebird are made of “incoloy”, a nickel-chromium alloy resistant to the effects of saltwater and mud. Each bird was fitted on one leg with a band issued to a licensed bird bander only, and inscribed with a unique coded number and, stamped or engraved on it, the return address of the banding scheme that produced the band. For many Asian shorebird species, there is a recommended band size that fits correctly around the tarsus. There are 36 different internal diameter sizes of bands used by six banding schemes in Asia. These range from 2.0 mm for passerines to 26 mm for large water birds, game birds and birds of prey. The metal band is attached to the left tarsus. Color flag allocations for the East Asian-Australian Flyway
Note: Regions with existing color flagging combinations are shown in bold text (Reference: Color Marking Protocol for Migratory Shorebirds in the East Asian-Australasian Flyway, Australian Bird and Bat Banding Scheme – Environment Australia)All information collected must be written clearly and concisely. This is important, as the data have to be submitted to the banding scheme whose bands are being used. Banders have to recheck entries and any erroneous entry is corrected immediately. The best and safest method of releasing birds is to allow the bird to walk away into the wind, but not towards the area from where it was caught. Shorebirds can be released at night away from bright lights, thick vegetation and those areas where the banding team is regularly moving across.
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