Cookies Policy

This site uses cookies. By continuing to browse the site you are agreeing to our use of cookies.

I accept this policy

Find out more here

Co-Operative Breeding in Riflemen (Acanthissitta Chloris) Benefits To Parents, Offspring and Helpers

No metrics data to plot.
The attempt to load metrics for this article has failed.
The attempt to plot a graph for these metrics has failed.
The full text of this article is not currently available.

Brill’s MyBook program is exclusively available on BrillOnline Books and Journals. Students and scholars affiliated with an institution that has purchased a Brill E-Book on the BrillOnline platform automatically have access to the MyBook option for the title(s) acquired by the Library. Brill MyBook is a print-on-demand paperback copy which is sold at a favorably uniform low price.

Access this article

+ Tax (if applicable)
Add to Favorites
You must be logged in to use this functionality

image of Behaviour

Two types of helpers were observed feeding young of the New Zealand rifleman (Acanthisitta chloris): "regulars" and "casuals". The former contributed significantly to feeding young from only one nest while the latter contributed a trivial amount to young from a number of nests. Regulars were usually unpaired adult males some of which acquired a mate from the brood they helped. While some casuals were unpaired adult males, most were current season offspring helping with their parents' second clutch. The relative contributions of parents and helpers in raising broods were measured to establish the benefits of co-operative breeding to offspring and feeders. Whether or not helpers were present while feeding young, the breeding female's contribution was the same. By contrast, the work load of the breeding male was significantly reduced when helpers were present, but even then he usually contributed more than this mate. That male parents benefited most from helpers feeding young was probably related to their being responsible for most of the feeding in the absence of helpers. A helper's presence did not improve productivity or the male parent's chance of survival. However, female parents of nests with regular helpers survived better than those without. Offspring fed by helpers were not heavier upon fledging nor were their chances of survival improved. The interval between fledging first clutch broods and laying second clutches was the same whether helpers were present or not.

Affiliations: 1: Edward Percival Field Station, University of Canterbury, Kaikoura, New Zealand


Full text loading...


Data & Media loading...

Article metrics loading...



Can't access your account?
  • Tools

  • Add to Favorites
  • Printable version
  • Email this page
  • Subscribe to ToC alert
  • Get permissions
  • Recommend to your library

    You must fill out fields marked with: *

    Librarian details
    Your details
    Why are you recommending this title?
    Select reason:
    Behaviour — Recommend this title to your library
  • Export citations
  • Key

  • Full access
  • Open Access
  • Partial/No accessInformation