Bird Observatory: Khoisan Karoo Conservancy
Bird observatories conduct long-term studies on bird populations, with a particular focus on those aspects of bird biology which are best investigated using bird ringing.
One of the objectives of the Karoo Research Centre is to establish the first bird observatory in South Africa, initiate a bird ringing unit, and commence a long-term study of the relevant aspects of the bird populations of the Khoisan Karoo Conservancy. The focus will be on establishing a baseline of quantitative information and then measuring the impacts of global change which result in departures from this baseline.
The initial focus will be on the common resident bird species in the Karoo Gariep Nature Reserve. The long-term goal for these species will be to detect trends in population sizes, trends in survival rates, trends in morphometrics, and trends in the parameters of primary moult. For example, using capture-recapture methods, ringing makes it possible to estimate population sizes of species for which exact numbers are difficult to determine by direct observation. Variations of the capture-recapture model are used to estimate survival rates, and with sufficient volumes of data, this can be done on an annual basis.
Data on morphological features such as wing length, bill length, tail length and tarsus length can routinely be measured on captured birds. Mass can be measured, and age and sex are determined. Data on the progress of the primary moult of individual birds can be recorded during regular bird ringing, and there is a moult model through which the timing and duration of moult can be estimated. We plan to collect enough moult data to be able to make estimates on an annual basis.
Small, but significant, numbers of ringed birds will be found dead by members of the public and reported to the national bird ringing project. This provides valuable information on the movement.
Climate change predictions suggest long-term trends in many of the features that can be investigated using bird ringing. The bird observatory, functioning systematically through the years, will help in estimating these trends and help establish which species are coping with climate change. It will provide an early-warning system for common species that are becoming rare, at a stage at which it is still feasible to develop mitigation strategies.
In a nutshell, a long-term ringing project in the Khoisan Karoo Conservancy will collect a wealth of information relevant to the conservation of the birds of the Karoo.