Life history trade-offs in a parental care-providing fish: the role of reproductive value, predation threat, and physiological condition on brood abandonment decisions by paternal largemouth bass

Parental care evolved as a means to maximize reproductive success at a cost to physiological and nutritional condition of the care-providing individual, and at a cost to future reproductive potential. Parental investment decisions are rooted in tradeoffs between these factors, and when the cost of care-provision is outweighed by potential future reproductive potential, a parent may forfeit current investment in an effort to maximize future reproductive success. Few studies have approached parental care decisions using offspring abandonment as a direct and ultimate fitness affect, and fewer yet have adopted a holistic approach to test how physiological and environmental conditions compare in influencing the decision by a parent to abandon their brood. I performed two separate, yet complementary, studies to test for the effects of several factors on brood abandonment decisions in largemouth bass (Micropterus salmoides); a model parental care-providing species. First, I tested whether mating success and simulated brood depredation affect the decision by paternal largemouth bass to abandon a brood. Second, I used a multivariate approach to jointly test for the influence of nutritional condition, hormonal stress, androgen concentration, and oxidative stress of brood-guarding paternal largemouth bass, and the threat of brood depredation (i.e., brood predator density), on brood abandonment decisions. Together, my results suggested a threshold for brood loss at which paternal largemouth bass were more likely to abandon what remains of a depredated brood, and that a high threat of depredation and reduced androgen concentration also influenced the decision by paternal bass to abandon care. My findings have implications for science-based management of a highly sought-after sportfish, as well as offer a novel approach for testing the inter-related effects of various abiotic and biotic factors on parental care decisions across taxa.

Name thesis:degree_name

M.S.

Level thesis:degree_level

Thesis

Discipline thesis:degree_discipline

Natural Res & Env Sciences

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2012

Author dc:creator

• Zuckerman, Zachary

Contributors dc:contributor

• Suski, Cory D.

• Parental care
• stress
• oxidative stress
• nutritional condition
• offspring abandonment
• recruitment
• reproductive success
• brood loss
• brood depredation
• Largemouth bass
• Micropterus salmoides
• fitness

Statement dc:rights

• Copyright 2012 Zachary Zuckerman

Language dc:language

en

Handle dc:identifier

http://hdl.handle.net/2142/31969

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/31969