Provisioning, growth and survival of Adélie penguin chicks at Cape Crozier, Ross Island, Antarctica
Understanding the factors that contribute to or limit reproductive success is a fundamental objective of the field of ecology, providing insight into the ways ecosystems function and facilitating better management of natural resources. Behaviors that benefit offspring often increase costs to parents...
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| Other Authors: | , , , , |
| Format: | Master Thesis |
| Language: | English unknown |
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Oregon State University
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| Online Access: | https://ir.library.oregonstate.edu/concern/graduate_thesis_or_dissertations/2b88qg24s |
| Summary: | Understanding the factors that contribute to or limit reproductive success is a fundamental objective of the field of ecology, providing insight into the ways ecosystems function and facilitating better management of natural resources. Behaviors that benefit offspring often increase costs to parents, and thus parents must adjust their level of investment under different conditions to maximize their fitness. Investigating the ways in which individual animals vary parental investment in response to changing environmental conditions is critical to predicting population responses to natural or anthropogenic changes in environmental conditions. I studied the relationships between provisioning, growth, and survival of Adélie Penguins at a very large, high latitude breeding colony where intraspecific competition for food is thought to limit reproductive rates and colony growth through density dependent processes. I measured three aspects of provisioning, which previous research has shown or suggested might represent variation in parental investment, with increased presumed benefits to chicks coming at an energetic cost to parents. These measurements of parental provisioning effort included: 1) the overall amount of food delivered; 2) the type of food delivered; and 3) the frequency of food delivery. I measured mass and skeletal growth, determined chick sex via molecular methods, and evaluated daily survival probability using quantitative methods which allowed for imperfect resighting probability. I collected data during two breeding seasons, one of which appeared to be relatively typical in terms of growth rates and breeding success (Austral summer of 2012-13; "2012"), and one characterized by apparent food limitation and depressed chick growth rates and reproductive success (Austral summer of 2013-14; "2013"). I compared provisioning, growth and survival at the level of individual penguin families in order to gain a more direct perspective of how trade-offs in parental investment may impact offspring growth and ... |
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