Maggie Brown received her MS in Ecology at UC Davis in 1998, with a thesis entitled, "Population genetic structure, kinship, and social associations in three harlequin duck (Histrionicus histrionicus) breeding subpopulations."
After completing her degree, she accepted a position as a biology instructor on the faculty at Bowdoin College, Maine (1998-2000). She is now the Senior Production Editor for the Public Library of Science (PLoS).
At UC Davis, Maggie was able to combine her background in molecular laboratory techniques with her lifetime interest in ecological fieldwork. Advances in molecular methodologies have enhanced research in areas of ecology that previously have been difficult or impossible to access. Long-term field research is costly in time and money, some species are very difficult to capture or observe in their natural settings, and some questions cannot be readily answered through field observations (for example, whether subpopulations are genetically distinct and therefore warrant special management). The goal of Maggie’s thesis was to combine genetic and behavioral methods at different scales in an investigation of dispersal, kinship and population structure in harlequin ducks (Histrionicus histrionicus).
Harlequin ducks, along with other sea duck species, possess life history traits that may make them more vulnerable to population declines than duck tribes with higher fecundity. Recent concerns about possible population declines resulted in petitions for listing the eastern harlequin duck population as threatened or endangered in the United States (Fish and Wildlife Service 1998). The petition for listing was rejected by the USFWS, in part due to insufficient information regarding population distinctness. However, in 1990 they were listed as Endangered in eastern Canada, and the harlequin remains a species of concern in several states and management units.
Harlequin ducks breed at relatively sparse densities in inaccessible habitat, and are secretive on breeding streams; consequently, they can be very difficult subjects for long-term mark-recapture studies. Maggie used microsatellite DNA techniques to determine whether harlequin ducks exhibit sex-biased patterns of genetic relatedness at breeding areas. Specifically, she compared average within-stream female relatedness to relatedness of females on different streams in Washington, Oregon and Montana. She then compared these patterns with those of males. In doing so, she was able to further examine larger-scale patterns of genetic structure that may be influenced by differential dispersal between the sexes.
Maggie’s studies indicated that, while females on the same stream may be more closely related to one another, there were no broad scale patterns of population differentiation among the harlequin ducks in the three states examined. These results provide new insight into several aspects of the breeding and social ecology of this species, and also indicate that the western population of harlequin ducks is not highly sub-divided. Accordingly, it appears that the western population of this species can be managed as a single management unit. Using molecular genetic methods to track and delineate populations can provide key information to develop sound management plans. Maggie has spear-headed these efforts in our group.