Editing Helpers at the nest (section)

== Associated effects ==

=== Reproductive success ===
Effects on reproductive success can be but are not always positive, and the strength of that positive correlation varies by species. Sometimes, the energy benefits to breeders, instead of being invested in improving reproductive performance, are used to offset reductions in reproductive performance.<ref name=":12">{{Cite journal|last1=Manica|first1=Lilian Tonelli|last2=Marini|first2=Miguel Ângelo|date=2012-01-01|title=Helpers at the nest of White-banded Tanager Neothraupis fasciata benefit male breeders but do not increase reproductive success|journal=Journal of Ornithology|language=en|volume=153|issue=1|pages=149–159|doi=10.1007/s10336-011-0718-x|bibcode=2012JOrni.153..149M |s2cid=16198295|issn=2193-7206}}</ref> However, in many species, nestling survival rates are increased from helper investments.<ref name=":2">{{Cite journal|last1=Cusick|first1=Jessica A.|last2=de Villa|first2=Miguel|last3=DuVal|first3=Emily H.|last4=Cox|first4=James A.|date=2018-02-23|title=How do helpers help? Helper contributions throughout the nesting cycle in the cooperatively breeding brown-headed nuthatch|journal=Behavioral Ecology and Sociobiology|language=en|volume=72|issue=3|pages=43|doi=10.1007/s00265-018-2470-1|bibcode=2018BEcoS..72...43C |s2cid=4702911|issn=1432-0762}}</ref> Further reproductive success benefits include better quality offspring,<ref name=":2" /> and nestling [[immune response]].<ref>{{Cite journal|last1=Valencia|first1=Juliana|last2=Solís|first2=Elena|last3=Sorci|first3=Gabriele|last4=de la Cruz|first4=Carlos|date=2006-07-01|title=Positive correlation between helpers at nest and nestling immune response in a cooperative breeding bird|journal=Behavioral Ecology and Sociobiology|language=en|volume=60|issue=3|pages=399–404|doi=10.1007/s00265-006-0179-z|bibcode=2006BEcoS..60..399V |s2cid=1898846|issn=1432-0762|hdl=10630/33525|hdl-access=free}}</ref>

=== Parental investment ===
Helpers at the nest can provide advantageous plasticity in the amount of [[Parental investment|investment]] parents need to give to their eggs and chicks. The presence of helpers can be associated with lower investments as the helpers can be depended on to provide certain elements of care and raising.<ref name=":12" /> For example, in the [[Superb fairywren|superb fairy-wren]], nests with helpers present exhibit different average egg sizes than those without helpers.<ref name=":02">{{Cite journal|last1=Langmore|first1=N. E.|last2=Bailey|first2=L. D.|last3=Heinsohn|first3=R. G.|last4=Russell|first4=A. F.|last5=Kilner|first5=R. M.|date=2016-11-30|title=Egg size investment in superb fairy-wrens: helper effects are modulated by climate|journal=Proceedings of the Royal Society B: Biological Sciences|volume=283|issue=1843|pages=20161875|doi=10.1098/rspb.2016.1875|pmc=5136590|pmid=27903872}}</ref> This plasticity can be seen in reference to change in climate conditions. In unfavourable conditions there is a need for female parents to maintain high egg investment, but in favourable conditions, egg investment by mothers declines as helpers can assist with some of the care-load. [[Superb fairywren|Superb fairy-wrens]] with helpers at the nest see average egg sizes increase in dry and hot conditions and decrease in colder conditions compared to nests without helpers.<ref name=":02" />