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Project Title: Fisher Relocation
Problem Statement
Fisher were extirpated from Nova Scotia near the turn of the century. In 1947/48, 12 ranch-raised fisher were released in the Tobeatic Game Sanctuary and from 1963-66, 92 wild fisher from Maine were released into the eastern mainland. The eastern population has been more successful, particularly in recent years, but fisher apparently have not colonized Halifax, Hants, Lunenburg or Kings counties (none have ever been recorded from Cape Breton) and the populations appear to remain geographically disjunct. The western population may have done poorly for genetic reasons (ranch stock, low number of animals released) and it would appear desirable to join the two populations together to expand the distribution and provide for gene flow.
Objective
To transfer fisher from areas of high population in Cumberland, Colchester and Pictou counties to locations between the two population centers and obtain samples from both populations (about 20) in order to test for genetic differences.
Methods
Trappers will be paid to live-trap fisher in cage traps in fall. They will be transported to Shubenacadie Wildlife Park, marked with tetracycline and transferred to the release site. Samples from accidentally trapped animals will be stored for DNA analysis.
Partners
Trappers Association of Nova Scotia (TANS), Canadian Parks Service, forest industry or other interested parties, and Regional Services.
Project Dates and Duration
October and November, a number of years unknown.
Progress to Date
In the early 1990's, it was thought that the fisher populations were on the rise as there was substantial increase in the number of fisher turned in through accidental trapping. Thus, DNR and the Trappers Association of Nova Scotia (TANS) devised a fisher relocation plan in an attempt to link the two isolated populations and increase the genetic diversity of the western population. To this end, 13 animals were caught in northeastern Nova Scotia in 1994, marked, and released in Lunenburg County. Limited (1 'mistake' fisher bag limit) harvest is now allowed in Pictou, Cumberland and Colchester Counties, with the remaining counties closed for fisher harvest to enhance the effect of relocation efforts.
In 1998, with support from the Trappers Association of Nova Scotia, a combined relocation plan and habitat research project was proposed. By the winter of 1999 fieldwork had begun. The objectives of this new project were to gain an understanding of fisher habitat preferences in their natural landscapes, model fisher habitat preferences with the aid of GIS technology, and to relocate animals into preferred habitat to try and link the two Nova Scotia populations. This project is an important effort by DNR to try to increase the viability of the Nova Scotia fisher population and to help fisher re-establish their original range across the province. An important longer term product will be improved knowledge of fisher habitat requirements. DNR is working cooperatively with the Trappers Association of Nova Scotia, and with Acadia University on this project.
In winter 1999, 12 animals were captured and held at the Wildlife Park at Shubenacadie until they were released in the spring of that year. These individuals were released back into the same areas in Cumberland County where they had been captured, each affixed with a radio collar so that their normal movements and habitat use in their home territories could be monitored.
From the radio telemetry data and winter harvest location data collected from Colchester, Cumberland, and Pictou Counties, superimposed over fisher habitat mapping developed from existing GIS forestry mapping, a preliminary fisher habitat model was created. Relevant attributes for the model were determined by consulting the literature for reports of habitat preference in other areas.
Approximately 10% of the harvest data was retained for cross-validation. The resulting model was used to predict habitat suitability for fisher in areas of Halifax and Hants Counties, and is being further tested by monitoring fisher movements after re-location. In spring 2000 fisher were moved to various areas within Halifax and Hants counties - several animals to areas of habitat identified by the model as most suitable for fisher, and several more to areas that are less suitable. Four individuals were ones which had been followed in natal areas in 1999 and then re-captured allowing us to account for some of the differences among individual animals in their response to the relocation. Following their release, animals have been monitored via radio-tracking.
Management Recommendations
Transfer enough animals to establish viable population in area between eastern and western populations and collect tissue samples from accidental captures for DNA analysis. Seek other partners to assist with further relocations.
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