Helpers increase the reproductive success of breeders in the cooperatively breeding cichlid Neolamprologus obscurus
Publisher DOI
Abstract
In cooperatively breeding animals, individuals other than breeders assist in raising young. While it is generally assumed that such helpers increase the reproductive success of breeders, positive effects can be cryptic and difficult to detect. Furthermore, measuring the effect of helpers in the wild is often difficult because multiple factors such as breeder’s individual quality or experience may affect their reproductive success. Thus far, best examples for fitness benefits of helpers come from a small number of long-term data sets in cooperatively breeding birds and mammals. In contrast, little is known about helpers’ effect on the reproductive success of other cooperatively breeding taxa, e.g., fishes. Here, we investigated the effect of helpers in the cooperatively breeding cichlid Neolamprologus obscurus. We analyzed field data collected during three years to elucidate the effect of helpers on reproductive success of breeders, while considering differences in the quality of breeders and size of their territories. As proxy for reproductive success, we measured the number of juveniles in the respective territory. Our results show that the number of juveniles increased with the number of helpers, while neither breeders’ quality nor the size of the territories had a significant effect. These findings increase our understanding of the beneficial effects of helpers in cooperatively breeding fishes, helping us to understand the evolution of such complex social system in general.
Date Issued
2018
Publication Type
Article
Subject(s)
Language(s)
en
Additional Credits
Journal
Behavioral ecology and sociobiology
Publisher
Springer-Verlag
ISSN
0340-5443
Access(Rights)
open.access