Maternal Care and Foraging in Bottlenose Dolphins
Maternal Care and Learned Foraging in Bottlenose Dolphins (Tursiops truncates)
Janalee Martin
Behavioral Ecology Fall 2012
INTRODUCTION
Maternal care is a major factor in juvenile development and studies dating back several decades have shown the impact of early life events on the development of behavioral responses to differences in maternal care (Francis and Meaney, 1999). Maternal separation causes acute stress in individuals resulting in them being extremely fearful in situations that they have never been in before. Animals tend to be more timid when exploring or feeding in new environments as well as exhibiting stronger reactions to loud noises (Meaney, 2001). These periods of stress cause individuals to focus their entire attention on the unfamiliar surroundings, instead of the particular task that they are trying to accomplish (Francis and Meaney, 1999). Individuals using their energy on making sure their surroundings are safe should be using it on key survival factors, like foraging. The knowledge of how to forage efficiently must be passed down to juvenile individuals so that they can develop the techniques that will ensure their survival. Knowing which foraging strategies and prey types that will provide them with a maximum energy gain is directly related to optimum foraging. The optimal foraging theory states that individuals optimize a currency and identify the decision rule that maximizes that currency while laboring under energy and time constraints. Along with that, the marginal value theorem suggests that there is a specific time that an individual should stop foraging in that specific food patch as the amount of energy gain begins to decrease the more the resources in the patch are exploited. These principles allow individuals to develop foraging strategies that will benefit them the most. Bottlenose dolphins (Tursiops truncates) have several strategies that they employ to help them forage successfully and ensure their survival.
Janalee Martin
Behavioral Ecology Fall 2012
INTRODUCTION
Maternal care is a major factor in juvenile development and studies dating back several decades have shown the impact of early life events on the development of behavioral responses to differences in maternal care (Francis and Meaney, 1999). Maternal separation causes acute stress in individuals resulting in them being extremely fearful in situations that they have never been in before. Animals tend to be more timid when exploring or feeding in new environments as well as exhibiting stronger reactions to loud noises (Meaney, 2001). These periods of stress cause individuals to focus their entire attention on the unfamiliar surroundings, instead of the particular task that they are trying to accomplish (Francis and Meaney, 1999). Individuals using their energy on making sure their surroundings are safe should be using it on key survival factors, like foraging. The knowledge of how to forage efficiently must be passed down to juvenile individuals so that they can develop the techniques that will ensure their survival. Knowing which foraging strategies and prey types that will provide them with a maximum energy gain is directly related to optimum foraging. The optimal foraging theory states that individuals optimize a currency and identify the decision rule that maximizes that currency while laboring under energy and time constraints. Along with that, the marginal value theorem suggests that there is a specific time that an individual should stop foraging in that specific food patch as the amount of energy gain begins to decrease the more the resources in the patch are exploited. These principles allow individuals to develop foraging strategies that will benefit them the most. Bottlenose dolphins (Tursiops truncates) have several strategies that they employ to help them forage successfully and ensure their survival.
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