Food preferences by birds using birdfeedersin winter: a The degree of use of a particular type of food at bird-feedersdepended on the overall use of food in the bird-feeder—each of the four types of food was significantly and positively correlated with that of the others (r s in Spearman rank-order correlations ranged between 0.60‒0.71, and all coefficients were significant even after ...
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