Behavioral paternity predicts genetic paternity in satin bowerbirds, a species with a non-resource-based mating system

he potential for di? erences between genetic paternity and paternity inferred from behavioral observation has long been recognized. These di? erences are associated with the challenge for females of seeking both genetic and material bene? ts; this challenge is less severe in species with polygynous, non-resource-based mating systems (such as leks) than in those with resource-based systems. We pres- ent the ? rst study of paternity patt erns in a non-resource-based species that does not form true leks. We compared paternity inferred from observed mating behavior to genetically assigned paternity in the Satin Bowerbird (Ptilonorhynchus violaceus) using eight microsatellite markers. Mating behavior was observed and recorded via automated video-cameras positioned at all bowers (29?34 bowers each year) in the study site throughout each mating season. We obtained blood samples and identi- ? ed mothers for 11 chicks in 9 nests. For all chicks, the most likely genetic father had been observed to mate with the mother in the year the chick was sampled. All most likely genetic fathers were assigned with high con? dence and all were bower- holding males. These results demonstrate that genetic paternity can be inferred from observed mating behavior with reasonable con? dence in Satin Bowerbirds. Observed male mating-success is therefore a reliable predictor of reproductive success, and this suggests that high skew in observed male mating-success translates directly to high skew in reproductive success.