Print PageA major hurdle with marine mammal conservation and management is to know if and when measurable short term responses result in biologically meaningful changes in populations. We are developing a bioenergetics approach to parameterize the transfer functions developed in the conceptual model developed by the NRC Committee on the population consequences of acoustic disturbance or PCAD. Our effort is directed at quantifying the life functions that are linked to vital rates, and how changes in these vital rates affect populations. Such an approach can identify species and or particular life history characteristics that are likely to be sensitive or resilient to acoustic disturbance. Using species that represent the range of life history patterns observed in marine mammals we are analyzing the existing data to determine whether there is a linkage between fine scale measurements of foraging behavior and reproductive success and survival. These data are being used to develop a time-activity budget to produce a first order quantitative assessment of the potential significance in terms of lost energy and/or time that foraging behavior or habitat utilization is potentially affected by acoustic disturbance.
Results/Conclusions
The ability to respond to environmental change appears to differ both between individuals and between species and has also been linked to differences in foraging behavior. There are also striking differences in the ability of some animals to adjust their foraging tactics because they are already operating at or near their physiological limits. This suggests that there may differences in the intrinsic ability of animals to respond to environmental fluctuations and human disturbance. That is some species may be more tolerant to acoustic disturbance and others more sensitive, but we should be able to gain insight into these differences by examination of the plasticity in the animals foraging behavior and ability to respond to natural environmental perturbations.
