It has been said that bird banding is at once both a delicate art and a precise science. Bird banding is a method of bird monitoring to track bird populations and demographic trends (characteristics of the population) over time. First, a bird is gently caught in a soft, fine net called a mist net. After being carefully removed by a biologist, a small aluminum band is placed around the bird’s leg like a bracelet. Engraved on the band is a unique number which will allow biologists to track the bird if it is recaptured. Next, data (e.g., age, sex, fat, feather molt, weight) about the bird are collected. Finally, the bird is released near where it was caught and continues its daily activities.
KBO implements point count surveys to monitor breeding bird distribution, diversity, and abundance. Point count surveys are completed during the breeding season, from early May through early July. On average 12 point count stations are sampled in a morning, but depending on terrain a morning route could range from 6 to 25 stations. Surveys begin at sunrise, and are completed within four hours. At each point count station, the observer records all birds that are seen or heard and estimates the distance to each individual during a 5-minute count period. Recording the distance to each bird detected allows estimation of detection probability.
KBO implements nest searching and monitoring to determine reproductive success rates. Nest success is an important metric to determine not only whether a species is present, but also how successful birds reproduce in a given habitat or area Nest searching is very labor intensive, so most studies are limited to a limited group of target species. During the breeding season, nests are located and then monitored every three to four days. By monitoring each nest intensively, it is possible to determine if and when young successfully fledge from their nests. Through nest searching the cause of nest failure can also be determined.
Spot mapping is a survey method that is used to literally map a bird’s territory. Spot mapping is relatively intensive, so a typical survey is limited to four to eight bird species. During a survey, individuals are mapped and their activity, movements, and interactions are noted. At the end of the season, after eight to ten surveys, an individual bird’s territory can be delineated. Such data can be used to determine bird density.
The Area Search is a quantitative, habitat specific survey method that is widely applicable in most habitats. It is useful for diversity measurements such as species richness, bird community composition, and relative abundance; as well as providing simple avian-habitat relationship, natural history and reproductive information. The method is also well suited for public education and training of observers.
Understanding whether birds are breeding successfully in an area provides information about bird/habitat relationships and bird response to habitat change. By observing the breeding behavior of birds, we can determine an index to reproductive success. Based on an individuals behavior (e.g., nest building or carrying food), we can assigned a breeding behavior score; the higher the score, the more likely that bird was nesting and successfully fledged young. This method is less labor intensive and less invasive than the more commonly used nest searching method.
On a species checklist, all bird species encountered during monitoring efforts (e.g. mist-netting, point counts) are recorded and breeding status is noted. This allows us to gather data on species that are encountered during a visit to a site, but perhaps not captured during the survey itself. The information gleaned from these checklists is used in various ways to monitor bird species. For example, species checklists are used at many of our long-term bird monitoring sites to monitor species over time so that we can determine changes in species richness. These lists can also be used in conjunction with vegetation surveys to determine which species are found in certain habitat types.