Should females prefer males with elaborate nests?

It is widely assumed that when males alone are responsible for nest building, nest characteristics should reflect the quality of its owner and that the nest itself should be an important cue in female choice. This, however, does not always have to be the case if, for example, nest attributes are an unreliable reflection of male quality. Here, we investigate whether females should prefer nest characteristics in a small marine fish, the sand goby, Pomatoschistus minutus. Previous findings suggest that female sand gobies prefer males that possess well-built nests (based on the amount of sand piled on top). It was unclear, however, whether females chose males based on the quality of the nest per se or some other, correlated quality of the builder. In the current study, we found conflicting evidence of whether males in good condition are able to bring a greater percentage of eggs to the hatching stage. In a field investigation, we also found that the relationship between body condition and the degree of nest construction was temporally unstable. Furthermore, when we experimentally disentangled nest quality from other male traits, we showed that females did not prefer to spawn with males that had the most elaborate nests. Together, these results suggest that females do not necessarily prefer males based on nest characteristics and may, instead, rely on multiple cues when choosing mates, the relative importance of which should vary depending on context.