The ecology and management of overabundant bird populations

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The long-term objective of my research program is to study the ecology of overabundant bird populations within the general framework of adaptive management. I propose to complete my studies on two populations of birds that have different dynamics and contrasting management systems. A first series of objectives deal with a temperate-nesting population of Canada geese that I have studied since 1992. With HQP, I have estimated several demographic parameters including breeding output and survival rates. We recently found that geese showed consistency in nest defence behaviour indicating personality differences. Pairs that nested earlier and laid more eggs were more defensive. I propose to look at the association between personality traits, dispersal, and survival using our ongoing marking program. My hypothesis is that pairs that have a fast pace of life and express bolder and more aggressive behavior should tend to disperse more and to have a lower survival rate. I also propose to incorporate all demographic parameters obtained during the last 15 years into a population model to simulate different control scenarios. Knowledge about the relative effects of survival and reproductive parameters on population dynamics will help managers deciding which actions should be taken to control temperate-nesting Canada geese. It has been suggested that reducing adult survival is more efficient in reducing population growth but this is not always applicable in urban settings nor socially acceptable. Reducing breeding output is an alternative and we recently showed how egg oiling and nest removal can affect dispersal behavior of geese.The second part of my program involves a population of ring-billed gulls breeding near Montreal. We also obtained several demographic parameters for this population based on nest monitoring and an ongoing marking program that relies upon resightings by HQP and an extensive network of volunteers. A key question about gull populations and their management is their fidelity to breeding colonies. The increasing use of roof tops for nesting and the concomitant but not successful control programs require a better understanding of breeding dispersal behavior. Nest-site and mate fidelity have been considered a characteristic of many seabird species but recent technology development suggests that this may not be a general pattern. I propose to compare migration pattern, mate fidelity, and nest-site fidelity of pairs that will be successful in fledging young and those that will have their nests experimentally removed. I will first use information obtained from our banding program that includes 18,500 sightings of 5,700 individuals. This will be complemented by long-term tracking of pair members using GPS-GSM technology. Results from this program that will examine both fundamental and applied questions will be useful to wildlife managers who deal with overabundant bird populations.