Avian Nests and Nest-Building as Signals

Abstract

Birds may signal their condition, health or parental disposition to mates through large nests or intense or elaborate nest-building. The mass, number or elaborateness of nests may exceed their strict reproductive requirements. In several species, courtship rituals include exhibition of nesting materials to mates, and some nests are not used for breeding. Signalling through nests or nest construction may occur both before and after mating and may involve either males or females. Only males appear to be involved in pre-mating signalling, while both males and females may signal after mating. In several species, nest size and nest building activity has been associated with the condition of nest-building males, and females in some cases, while the evidence for parental disposition has been more mixed. Nest defence capacity has also been associated with nest size. In some species, males attract more mates through construction of multiple nests not related to breeding. The benefits obtained by males after pairing through differential allocation of their mates have been found in several species in terms of larger clutches, earlier hatching, biased sex ratios and increased parental investment. There is less evidence of this type of benefits for females. Measured responses of assumed receivers of the information provided by active nest construction may positively affect their fitness. Predators are probably attracted to bulky nests and so nest predation may have selected for concealed nests and for inconspicuous nest building activities, which has probably limited exaggeration of nest-building signals. There is also some evidence that ectoparasites and brood parasites may be attracted to bulky nests. Although signalling through nest construction appears as a plausible evolutionary scenario, much more empirical work needs to be done to demonstrate the relevance of nest-building signals.

Causes and Consequences of Intraspecific Variation in Nesting Behaviors: Insights from Blue Tits and Great Tits

“…For blue tit and great tit nest building behaviors to be extended phenotypic signals of the building females' quality, they must be associated with costs (Moreno, 2012). Evidence of nest building being energetically expensive comes indirectly from studies showing that both species often travel considerable distances to collect nesting materials (Hansell, 1995;Surgey et al, 2012) whilst more direct evidence comes from studies specifically examining the energetic costs of nest building.…”

“…However, some species build structures that signal their phenotypic quality and whilst species such as bowerbirds build structures whose sole purpose is to attract a mate (Schaedelin and Taborsky, 2009), nests also contain eggs and/or offspring which suggests a direct trade-off between the conflicting requirements of natural and sexual selection (Sergio et al, 2011). For nest building behaviors to be extended phenotypic signals of the building individuals' quality, they must reliably indicate the quality of the builder by being associated with energetic costs (Nager and van Noordwijk, 1992;Maynard Smith and Harper, 2003;Moreno, 2012). There is now evidence that constructing a nest is energetically expensive for birds and that whilst those costs are less substantial than provisioning nestlings or incubating eggs, they are nevertheless far more substantial than they were generally considered to be just a couple of decades ago (e.g., Withers, 1977;Hansell and Ruxton, 2002;Soler et al, 2007;Moreno et al, 2008Moreno et al, , 2010; reviewed by Mainwaring and Hartley, 2013).…”

How does The Bird-nest Incubation Unit Work?

“…Various roles have been postulated for nests -defence, sexual signalling, signals of parental fitness, etc., and often are considered to reflect conflicting demands of the adults (Moreno, 2012;Mainwaring et al, 2014aMainwaring et al, , 2015. In some instances, factors affecting nest characteristics appear to be opposed.…”

Nest Insulation in the European Robin (Erithacus Rubecula): Effects of Latitude and Construction Materials

“…This interest has considered the various roles of nests (Moreno, 2012;Mainwaring et al, 2014a;Deeming and Mainwaring 2015) as well as quantitative analysis of materials used in construction, which can be used to distinguish nests between species (Britt and Deeming, 2011;Crossman et al, 2011;Biddle et al, 2015Biddle et al, , 2016. Moreover, there are significant relationships between environmental conditions and nest composition with individuals of species nesting in colder, high latitude environments building better insulated nests (Crossman et al, 2011;Britt and This study investigated the materials used in nests of the European Robin (Erithacus rubecula) with particular reference to their role in determining the insulation afforded by the wall structure.…”