Supplementary feeding increases nestling feather corticosterone early in the breeding season in house sparrows

Abstract

Several studies on birds have proposed that a lack of invertebrate prey in urbanized areas could be the main cause for generally lower levels of breeding success compared to rural habitats. Previous work on house sparrows Passer domesticus found that supplemental feeding in urbanized areas increased breeding success but did not contribute to population growth. Here, we hypothesize that supplementary feeding allows house sparrows to achieve higher breeding success but at the cost of lower nestling quality. As abundant food supplies may permit both high‐ and low‐quality nestlings to survive, we also predict that within‐brood variation in proxies of nestling quality would be larger for supplemental food broods than for unfed broods. As proxies of nestling quality, we considered feather corticosterone (CORT f), body condition (scaled mass index, SMI), and tarsus‐based fluctuating asymmetry (FA). Our hypothesis was only partially supported as we did not find an overall effect of food supplementation on FA or SMI. Rather, food supplementation affected nestling phenotype only early in the breeding season in terms of elevated CORT f levels and a tendency for more variable within‐brood CORT f and FA. Early food supplemented nests therefore seemed to include at least some nestlings that faced increased stressors during development, possibly due to harsher environmental (e.g., related to food and temperature) conditions early in the breeding season that would increase sibling competition, especially in larger broods. The fact that CORT f was positively, rather than inversely, related to nestling SMI further suggests that factors influencing CORT f and SMI are likely operating over different periods or, alternatively, that nestlings in good nutritional condition also invest in high‐quality feathers.

Plasma 1α-Hydroxycorticosterone as Biomarker for Acute Stress in Catsharks (Scyliorhinus canicula)

“…Taking into account that 1α-hydroxycorticosterone is not commercially available and it has a similar chemical structure and an identical molecular weight as cortisol, two UPLC-MS/MS quantification methods, both developed and validated at the Stress Physiology Research Group (Ghent University, Belgium), for cortisol, its precursors and phase I metabolites (Aerts et al, 2018) and for corticosterone and its phase I metabolites (Salleh Hudin et al, 2017), respectively, were combined and optimized for shark plasma. Subsequently, a wide range of preliminary plasma samples obtained from sharks and rays were analyzed, after which the most abundant ion fragment was used for quantification of plasma 1α-hydroxycorticosterone, while four other ion fragments were chosen for qualification of this hormone.…”

Individual consumption of supplemental food as a predictor of reproductive performance and viral infection intensity

“…The implications of this strategy on long-term population viability are, however, less clear. For example, some evidence suggests that offspring of older parents reveal reduced survival and recruitment (Torres, Drummond, & Velando, 2011), while others have shown that enlarged broods can lead to reduced individual survival (Naguib, Riebel, Marzal, & Gil, 2004), increased levels of stress (Salleh Hudin et al, 2017), and that SF may in fact increase reproductive success without resulting in viable populations recovery (Peach, Mallord, Ockendon, Orsman, & Haines, 2015). Our results are limited to data from a single breeding season and therefore an ongoing assessment of juvenile quality and long-term survival is required in this system in order to evaluate the implications of individual supplemental feeding on population-level fitness.…”

The Use of Nest Boxes in Malaysia: Design and the Potential for Research and In-situ Conservation of Birds

“…To either achieve the goal of population expansion or improve the research of these birds, nest boxes have been used to act as artificial nest cavities to attract these birds (Lambrechts et al, 2012). These secondary cavity-nesting birds may range from certain passerines (Cooper & Bonter, 2008;Gelter & Tegelström, 1992;Hanmer et al, 2017;Hudin et al, 2017;Miller, 2002;Riyahi et al, 2022;Zhang et al, 2021) and non-passerines especially raptors (Calabrese et al, 2020;Geduhn et al, 2016;Liébana & Sarasola, 2013;Raid, 2012;Rejt, 2001;Richards et al, 2004;Zárybnická et al, 2016), parrots (Olah et al, 2014;Ortiz-Catedral & Brunton, 2009;Wimberger et al, 2017), hornbills (Cremades et al, 2011;Pasuwan et al, 2011), and waterfowls (Davis et al, 2007;Gong et al, 2018).…”

“…The use of nest boxes has contributed to a wide range of research topics varying from breeding ecology (Arct et al, 2022;Beasley & Parrish, 2009;Davis et al, 2007;Hanmer et al, 2017;Mainwaring et al, 2015;Palko et al, 2011), feeding ecology (Balčiauskienė et al, 2005;Hudin et al, 2017;Rejt, 2001), nest site preference (Cooper & Bonter, 2008;Hanmer et al, 2017;Miller, 2002;Olah et al, 2014;Ortiz-Catedral & Brunton, 2009), conspecific and heterospecific interactions (Gong et al, 2018;Zárybnická et al, 2016), as well as occupancy rate (Liébana & Sarasola, 2013;Sudarmaji et al, 2021;Zhang et al, 2021). Additionally, some studies retrieved nestlings, breeding pairs, or even nest materials from nest boxes to assess the presence of ectoparasites (Hanmer et al, 2017;Proudfoot et al, 2006;Soltész et al, 2018) and the effect of rodenticide exposure (Richards et al, 2004;Geduhn et al, 2016), as well as for population genetic studies (Gelter & Tegelström, 1992;Riyahi et al, 2022).…”

“…Some studies may consider surveying targeted species' breeding or home range before nest box provisioning (Calabrese et al, 2020;Mainwaring et al, 2015;Richards et al, 2004). These nest boxes were either nailed or tied to trees (Arct et al, 2022;Maziarz et al, 2017;Olah et al, 2014;Ortiz-Catedral & Brunton, 2009;Palko et al, 2011) or else placed on man-made structures (Beasley & Parrish, 2009;Hudin et al, 2017). While many studies may not report the orientation of the nest boxes, some studies from the temperate and subtropical regions have highlighted the preferred position of the entrance facing the east to the southeast direction (Miller, 2002;Zhang et al, 2021).…”