Loons (Gavia immer) and people compete for lakeshore frontage
2007 Impact statement- Walcott, Charles
abstract
Common loons nest on swampy hummocks at the edge of lakes. Human development for summer homes and recreational use is displacing the loon`s nest habitat, endangering the species. We find that loons will use nest platforms to breed, but initially such platforms result in escalated territorial battles, often fatal, among the male loons. Furthermore, with a large numbers of platforms, these battles continue and reduce reproductive success. Finding the optimum platform density for a particular lake is clearly important.
submitted by
- Walcott, Charles | Professor Emeritus/a
issue being addressed
Common loons are a threatened species in the northern United States. This is due in part to competition with humans for lake use and in part to environmental hazards, such as mercury poisoning and botulism. My colleagues and I are interested in the basic biology of loon territoriality and the communication system that loons use to acquire and maintain it. By marking individual loons including chicks, we are able to establish both the long-term demography of the species and follow the behavior and life history of individuals in our study area near Rhinelander, Wisconsin. Many lake owners feel passionately about their loons, and the general public associates the call of the loon with northern lakes. Thus there is great public interest in preserving the species.
response
We have experimented by putting platforms on 10 lakes and observing 10 comparable lakes as controls. All 10 platforms were used by the loons, but on four of the 10 platforms, intruding males displaced the resident males. In contrast, none of the males on control lakes were displaced. Males on lakes with platforms became more aggressive, gave longer territorial calls, and were less successful in reproduction the first year. These results have been published in the scientific literature and several popular articles are under review.
impact assessment
It is too soon for this work to have had a substantial impact. The technical paper has just been published, and popular articles, while written, have not yet been accepted for publication.
academic priority area
- Environmental Sciences | CALS academic priority
- New Life Sciences | CALS academic priority
topic description
Preservation of threatened species
has geographic focus
- Massachusetts | state
- Minnesota | state
- Vermont | state
- Michigan | state
- Wisconsin | state
- New York State | state
- New Hampshire | state
- Maine | state
funding source description
- Unrestricted funds
- National Science Foundation
collaborators
- John H. Mager, Ohio Northern University
- Walter Piper, Chapman University
key personnel
- John Mager
- Walter Piper
mission focus
- research | project type
From CALS annual faculty reporting. Imported on August 5, 2008