Benefits of foundress associations in the paper wasp Polistes dominulus: increased productivity and survival, but no assurance of fitness returns

Successful Polistes dominulus nests can be started by one or more nest founding queens (foundresses). Consequently, there is much interest in the specific benefits that induce cooperation among foundresses. Here, we experimentally demonstrate one major benefit of cooperation, namely that multiple foundresses increase colony productivity. This increase is close to the value predicted by subtracting the productivity of undisturbed single-foundress colonies from the productivity of undisturbed multiplefoundress colonies. However, we found no evidence that an associating foundress’ contribution to colony growth is preserved if she disappears (assured fitness returns). Our correlational data suggest that cooperation provides survival benefits, multiplefoundress colonies are more likely to survive to produce offspring than are single-foundress colonies, and individual foundresses in multiple-foundress groups are less likely to disappear before worker emergence than foundresses nesting alone. Therefore, association provides substantial productivity and survival benefits for cooperating foundresses.