Grant: Discovery Grants Program - Individual

It is very difficult to estimate the abundance of animals when they form open populations. This means that there are animals entering and exiting the population at a rate that is usually unknown. Mark and recapture models are effective for measuring abundance when used on closed populations where there is no immigration or emigration of animals. However, when mark and recapture models are applied to open populations of animals, such as large pelagic species, we must estimate through a maximum likelihood approach the rates of immigration and emigration and this biases the estimates of abundance. In this research program, by integrating conventional and cutting edge new technology, I will develop and test new innovative procedures to accurately determine values of variables that form key assumptions for the development of accurate mark and recapture model estimates of abundance for open populations of large pelagic species. Present estimates are inaccurate because critical assumptions have not been tested as the tools required to do this did not exist.