Digital camera and software for image analysis

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Three major projects in my laboratory require the use of an image analysis system to measure the morphometric and meristic characteristics of juvenile fishes and fish scales. In the St. Lawrence estuary, two sympatric populations of rainbow smelt are morphologically distinct in spite of high levels of gene flow. A major objective of my Discovery grant is to test the hypothesis that foraging during early development in specific estuarine habitats generates the selective forces leading to independent phenotypic trajectories of the two smelt populations. We aim to document the development of specific morphological traits and relate these to estimates of morphometric-specific mortality rates in different environmental settings. A second project aims to estimate the heritability of alternative male reproductive tactics and their associated morphologies in Atlantic salmon. Specifically, we aim to test the hypothesis that heritability of traits contributing to increased foraging efficiency in rapid currents (and hence increased growth rates) favours the development of early maturity among the progeny of sneaker males. In both projects, high-resolution digital images and image analysis software are required to accurately measure the morphological traits of small juvenile fishes. Finally, we annually read and measure the scales of hundreds of juvenile and adult salmon from two reference rivers in Quebec to track the relationship among size-selective marine mortality, environmental variation at sea, and total marine mortality rates. Once again, high-resolution digital photographs and image analysis software are essential in measuring scale microstructure. We request funds to purchase an Olympus DP 20 2MP, associated software and light source. The camera does not require a computer to acquire images, only a monitor. Images are stored on a 1GB flash memory and downloaded on an independent computer and processed using the Image Pro Express (V6) software at a later date. This equipment will replace an old, analog-based system that is no longer functional.