Some interesting personal observations
In December 2009 Gudrun and I between us ringed 12 red-billed queleas in Windhoek and a further 9 on the farms Kakuse and Tsutsab north of Tsumeb. What is of interest is the difference in mass of the birds captured in the different areas. If one discards the heaviest and lightest bird from each set the remaining 10 city birds averaged 21.2 g (range 19.8 - 23.0 g) while the remaining 7 country birds averaged only 16 g (range 14.5 - 17.8 g). The city slickers were on average a whopping 32% heavier than their country cousins. While this is based on a small sample of unsexed and unaged birds it does appear that the city slickers which plunder the seed on our feeding stations have a very much easier life than those in the country at that time of the year when neither seeding grass nor standing grain crops are available to them.
Lanioturdus
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