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bioRxiv · 10.1101/2023.07.10.546769

Prospecting is physiologically costly in a resident cooperative breeder, the Florida scrub-jay

Abstract

Prospecting is an understudied yet pivotal information-gathering process often preceding natal dispersal. While prospecting may enable individuals to optimise dispersal outcomes and obtain high quality territories, it is also likely to incur costs stemming from energy expenditure and predation risks. This trade-off may drive individual differences in prospecting effort. We tested for evidence of costs of prospecting behaviour in a wild population of Florida scrub-jays, Aphelocoma coerulescens, which prospect as nonbreeding helpers. Using random sampling across all helpers, we compared prospecting effort--approximated by frequency, distance, and activity level--with body mass changes and oxidative stress levels. We tested if prospecting incurred costs and if early-life body condition predicted subsequent prospecting effort. Prospecting frequency was positively linked to oxidative damage but not to any loss in body mass during the breeding season, suggesting that extra-territorial movement costs manifest unevenly. Early-stage body condition did not affect subsequent prospecting effort across a large set of helpers, but early-stage body condition and morphometric measures did correlate with subsequent oxidative status of those sampled. Our results suggest that prospecting movement carries some physiological costs, perhaps contributing to individual differences in prospecting. This research highlights how body condition plays a role in trade-offs between information gathering movement and physiological costs of movement itself, ultimately providing insight on the evolution of prospecting in social species. HIGHLIGHTSO_LIProspecting prior to breeding enables informed dispersal but incurs cost C_LIO_LIWe tested whether prospecting by nonbreeding Florida scrub-jays results in physiological costs or varies with initial condition C_LIO_LIWe measured oxidative status using assays testing antioxidant capacity and oxidative damage C_LIO_LIFrequent prospecting was linked to subsequent oxidative damage C_LIO_LIEarly-stage body condition and wing length affected subsequent oxidative status C_LI

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Suh, Y. H., Taff, C., Bowman, R., Fitzpatrick, J. W.. 2023-07-10. Prospecting is physiologically costly in a resident cooperative breeder, the Florida scrub-jay. https://doi.org/10.1101/2023.07.10.546769

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