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The New Mexico Breeding Bird Atlas Project Atlas Handbook

Measuring the relative abundance of each species may be important for detecting difference in bird populations between various areas of the state and changes in bird populations over time. These differences and changes may not be as quickly or easily visible from presence/absence breeding information, as from timed counts of birds during atlas work. Follow the methods on page 9 to record relative abundance. Select which kilos you plan to survey for relative abundance (Figure 2). You may choose any eight kilos (or more if access is easy) and conduct the relative abundance counts in any order. The two-hour counts may be divided between visits to a particular kilo, as long as birds are actively singing. For each kilo, record the number of species (Figure 3) with individual species checked off (Figure 4) on the relative abundance card included in your packet of materials. Note that visits 1-4 are on one side of the card while visits 5-8 are on the other side. For more than eight kilos, request an additional relative abundance card from you regional organizer.