Date of Award
American marten (Martes americana) were extirpated from Michigan’s Lower Peninsula (LP) in 1911, and subsequently from the Upper Peninsula (UP) in 1939 due to habitat loss and unregulated trapping. The species was later reintroduced in the UP in the mid-1950s, and to the LP in the mid-1980s. Previous research has determined the small founding sizes used in the LP reintroductions have resulted in losses of genetic diversity, while research in the UP has produced discordant results concerning the effects of the reintroduction methods on genetic health and population structure. Since past research of marten in the LP, no additional reintroductions have occurred to mitigate further diversity loss, and little is known of the current status of marten genetic health or long-term population viability. The objectives of this research were to reevaluate the current genetic health of marten in Michigan, and determine the long-term population viability of marten in the Manistee National Forest (MNF). Microsatellite markers were used to calculate estimates of genetic health, and population viability analysis (PVA) was performed to determine viability over the next 100 years. Results of this research indicate the reintroduced marten populations in Michigan’s LP display evidence of genetic diversity loss due to small founding size and isolation in a fragmented habitat. Marten exhibited low levels of allelic richness, effective breeding size, and showed increases in inbreeding levels when compared to previous marten research. Marten in Michigan’s eastern UP also displayed signs of reduced genetic diversity, which was congruent with previous findings indicating population structuring reflective of multiple source locations. PVA indicated the MNF population was likely to maintain demographic viability, but would lose genetic viability within the next 100 years, although the use of non-population specific reproduction and survival rates may have overestimated viability results. It is recommended further research take place to identify factors that may be limiting population growth in marten populations of the LP. A translocation of marten to the LP populations is also recommended to mitigate further genetic diversity loss and preserve long-term viability of marten in Michigan.
Hillman, Tamara L., "Genetic Health and Population Viability of Reintroduced American Marten in Michigan" (2014). Masters Theses. 741.