Ecology section at the Conte Anadromous Fish Research Center In the ecology section at CAFRC, we examine the effects of biotic and abiotic factors on population dynamics and ecology of anadromous fishes. Emphasis is on an integrative approach, combining field, laboratory, and modeling studies and work spans a wide range of temporal and spatial scales. We explore population patterns occurring over decades and landscapes, and short-term, regional experiments illuminate these patterns. The primary objectives of the population ecology section are to identify population bottlenecks in space and time and to examine mechanisms responsible for population dynamics and fish growth. The result will be a clearer understanding of forces shaping population fluctuations and an improved ability to forecast population trends.   NEW: Download our new Software Creates and converts input files for over 50 genetic analysis software programs Current areas of research: Individual tagging studies. Detailed, fine-scale studies of stream fish growth, survival and movement are geared to identify patterns and mechanisms responsible for yearly and spatial (watershed) variation in population dynamics and life history tactics. The three Atlantic salmon studies span a range of environmental conditions (Massachusetts to New Brunswick), management (stocked to natural reproduction), and human influence (Massachusetts to New Brunswick). Jason Coombs is examining reproductive success, family-dependent growth, survival and movement, and metapopulation dynamics of brook and brown trout in the Massachusetts stream (the West Brook) Parentage assignment/Common garden studies. Studies combining parentage assignment techniques with regional and local assessments of variation in growth and survival of Atlantic salmon juveniles aim to evalute the relative importance of genetic (family differences) and environmental (river differences) effects. In one series of studies, we stocked fish from the same families into eight rivers and measured growth and survival of fish from the different families. In another, we stocked fish from 45 families into a major tributary system of the Connecticut and will evaluate smolt production and growth of fish from the various families. In a third, we have combined family analysis with the individual tagging studies above to determine the extent of familiy differences throughout the freshwater phase of young salmon. Many of these studies are in collaboration with Dr. Keith Nislow. Effects of stocking and emergence timing on survival and growth trajectories. In a series of studies, we have evaluted the effects of timing of stocking in three rivers (Letcher and Terrick, 2001) and are currently determining the effects of stocking/emergence date on growth and survival of Atlantic salmon through smolting by resampling individually-tagged salmon from three stocking dates and from the date of natural emergence. Fry from ten mothers were stocked in each of the four treatments (early, middle, late stocking and natural emergence). Fish with the same mother in the different treatments were identifiable because each lot was mated with a different father. Developoment of a predation tag. Jamie Pearlstein is working with Russ Lindgren of Biotags to develop and apply a radiotag that will indicate when a tagged fish (salmon smolt) has been eaten by a predator. Development, testing and application of PIT tag antennas.Todd Dubreuil has been working with Sean Casey and Rodger Clark of Destron-Fearing to develop in-stream Passive Inegrated Transponder (PIT) tag antennas. Rectangular pass-through antennas are in place in the Massachusetts and Maine study streams and extensive in-stream sampling using 'wand' antennas is underway. Development of an all-flow smolt trap. Justin Scace has designed and is testing a smolt trap for small streams that will effectively capture migrating fish in low to high spring flows. The design combines a rotary screw trap with resistance board panels to funnel most of the water through the screw trap. At low flows, when thescrew trap is ineffective, the resistanceboards guide the water to a removable fyke net. Growth variation among Atlantic salmon stocks. Mariska Obedzinski compared developmental and growth rates among three Down East Maine rivers, the Penobscot and Connecticut rivers. Assessing the genetic variability of Connecticut river Atlantic salmon will indicate to what extent the population has been bottlenecked and what measures will need to be taken to reduce inbreeding. Selection analysis with juvenile Atlantic salmon. Using data from the West Brook individual tagging study, we have been using traditional selection approaches and new methods based on multi-state mark-recapture models to evaluate the seasonal variation in the intensity of size selection for salmon and trout. Ecology Section publications Ecology Section Members Personnel Dr. Ben Letcher - Section leader Matthew O'Donnell - Fish Ecologist Todd Dubreuil - Fish Ecologist Dr. Kitty Griswold - Population Geneticist Aimee Varady - Research technician   Graduate Students Gregg Horton - (Ph.D., 2000- ) Growth and mortality of individually-tagged Atlantic salmon in Shorey Brook, ME. Jason Coombs - (Ph.D., 2002- ) Brook trout and Brown Trout geneology reconstruction and metapopulation dynamics. Douglas Sigourney - (Ph.D., 2001- ) Growth and mortality of individually-tagged Atlantic salmon in Catamaran Brook, New Brunswick. In collaboration with Dr. Rick Cunjak, University of New Brunswick. Jamie Pearlstein - (M.S., 2001- ) Development and application of a predation tag. Mariska Obedzinski - (M.S., 2000-2004) Family and population variation in feeding and growth of Atlantic salmon juveniles. Justin Scace - (M.S., 2000-2004) Building a better smolt trap. Matthew J. O'Donnell - (M.S., 1997-2000) Age, size, hatch-date and growth rate distribution of young-of-year of American shad in the Connecticut River Abstract Melissa S. Grader - (M.S., 1997-2000) Studies investigating the factors influencing the diet and growth of juvenile Atlantic salmon Abstract, e-mail J. Nathan Henderson - (M.S., 1997-2000) Predation by resident salmonids on Atlantic salmon (Salmo salar) fry stocked in southern New England streams Abstract, e-mail Stephanie Carlson - (M.S., 2000-2002) Growth and mortality of individually-tagged brook and brown trout in West Brook, MA. Abstract, e-mail