PT  - JOURNAL ARTICLE
AU  - Eduardo S. A. Santos
AU  - Regina H. Macedo
TI  - Helpers increase daily survival rate of Southern Lapwing (<em>Vanellus chilensis</em>) nests during the incubation stage
AID  - 10.1101/179606
DP  - 2017 Jan 01
TA  - bioRxiv
PG  - 179606
4099  - http://biorxiv.org/content/early/2017/08/22/179606.short
4100  - http://biorxiv.org/content/early/2017/08/22/179606.full
AB  - Cooperative breeding is characterized by reproduction in the presence of helpers. The impact that these helpers have on the reproductive success of group members is one of the long-standing questions in cooperative breeding literature. In several cooperative species, helpers are known to provide benefits during different stages of the reproductive cycle. The aim of this study was to investigate whether helpers increased the daily survival rate of nests during the incubation stage in the Southern Lapwing (Vanellus chilensis), a plover with a cooperative breeding system. Southern Lapwings have a variable mating system, with some breeding groups composed of unassisted pairs, and others that breed in the presence of helpers. We found a positive effect due to the presence of helpers on the daily survival rate of nests, leading to a probability of nest success of 83%, compared to 51% for nests of unassisted pairs. Our study provides evidence that helpers can have important fitness consequences to group members during the egg-incubation stage.