Scientific publications

The report presents a method of making coloured plastic rings to mark small passerine birds with unique remote readable combinations of leg rings tested over 15 field seasons. As a material for making of the rings, we used plastic binding combs. During testing, we marked Sylvia and Phylloscopus warblers by rings with an inner diameter of 2.8 and 2.2 mm, respectively, using 0.6 mm thick plastic of all available colors. Over the years of testing the rings, we have found 9 colours of binding combs for sale. Rings of such bright colours as yellow, red, orange, and blue were the best. Tags with combinations of black, white, green, blue, and purple were somewhat more difficult to read. The proposed rings are formed on a hot rod; the ends of the rings are formed without overlap, in a joint, like standard aluminum rings. Rings made by the proposed method can be used similarly to the standard aluminum rings. It is necessary to separate the ends of the ring to a width slightly exceeding the diameter of the bird's leg, put the ring on the leg and squeeze until the ends touch. With the used thickness of the material and the diameter of the wall curvature, the strength of the proposed rings is similar to that of a standard aluminum ring. We have not registered any successful attempts to remove or deform rings by birds. The height of the rings is selected depending on the research tasks and the desired number of individual colours combinations, ranging from 3 to 6 mm. The production procedure is described in detail in the report.