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University of Michigan Biological Station

The University of Michigan Biological Station (UMBS) was founded in 1909.

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Evaluating the Presence, Distribution, and Genetic Origins of fisher (Pekania pennant), a species previously thought to be extirpated from the Lower Peninsula of Michigan

Terrestrial
Project Abstract: 
The overall goal of this research is to detect fisher presence in habitat where they were once thought to be extirpated. The research proposed here will consist of two objectives: 1) identify current distribution of fishers throughout the Lower Peninsula of Michigan, and 2) identify the genetic origin of fishers in the Lower Peninsula. This research will provide information regarding if and where fishers can be found throughout the Lower Peninsula and where they originated from. An accurate understanding of these factors is necessary for management decisions going into the future. A goal of this research is to provide baseline data on the distribution of fishers and size of the population within the Lower Peninsula. Management strategies are only effective if fishers are present in the areas they are implemented. Determining the genetic origins of these fishers is important for knowing whether these individuals are derived from a remnant population or recolonized from surrounding areas. Based on these origins, decisions for how intervention is taken can be more specifically defined and targeted. Biodiversity is important for the assurance and continuation of proper functioning ecosystems (Mori 2013). Human activities that cause habitat loss and fragmentation can alter functional diversity in the ecosystem (Suarez and Andres 2020). These alterations can cause severe declines in species. These declines make smaller populations more susceptible to demographic and environmental stochasticity (Wilson and Arcese 2008). Demographic stochasticity increases species extinction risk in small populations because coincidental shifts in individuals have greater effects than those in larger populations, which can cancel out these shifts (Hastings and Melbourne 2008). Loss of a species causes a cessation in the ecological interactions in which that species took part and leads to a degradation of ecosystem function (Valiente-Banuet et al. 2015). Recolonization of areas in which species were extirpated can take place if suitable habitat is present and there is sufficient population connectivity between metapopulations (Butler et al. 2021). Metapopulations function as a way for species perseverance in a specific area based on migration from surrounding local populations (Harrison and Taylor 1997). However, recolonization and dispersal of species into areas where habitat loss and fragmentation occurred happen at different rates than in previously uncompromised areas (Joshi et al. 2006). Current conservation management practices often use an indicator species, referred to as Management Indicator Species, as a measure of health in an ecosystem. The fisher, Pekania pennanti, formerly Martes pennanti, is useful as an indicator species because of its reliance on complex mature forest ecosystems for habitat (USDA 2014). Historically, fishers ranged across much of Canada and the northern United States extending from the western to the eastern seaboards (USFWS 2019). By the 1930’s, logging coupled with over trapping, caused extensive decline in fisher populations. Fishers were extirpated from many areas along their southern reaches, including all of Michigan (Vinkey 2006). As a predator, removal of fishers caused unintended impacts to ecosystem function of their prey and habitat (Williams et al. 2007). The closing of trapping seasons, along with reintroduction efforts, have allowed fisher to return to portions of their previous range (Ruggiero 1994). In 2013, there was a fisher sighting in North Allis, Michigan; this was confirmed by the Michigan Department of Natural Resources (Michigan Wildlife Conservancy 2013). However, there were no previous reintroductions in the Lower Peninsula. Furthermore, there have been multiple instances in which fisher presence has been detected, visually and genetically, in recent years (Phil Huber - personal communication, Mazzola – unpublished data). Mazzola - unpublished data detected 9 confirmed fisher samples from 8 different locations through a non-invasive survey. It has not been determined whether these detections of fisher presence are isolated incidents or the result of a fisher population in the Lower Peninsula. In the southern Lower Peninsula, there is large-scale urbanization and conversion of natural habitat to agricultural land. Human land use has negative impacts on native species and can act as a barrier to their movement and dispersal (Jha 2015, Cozzi et al. 2020). Due to its geography and human activity, potential habitat for fishers in the Lower Peninsula resembles an isolated patch. This isolation affects the dispersal of the fisher population that were present in the Lower Peninsula and/or fishers of surrounding metapopulations in the region. The lack of evidence for fishers in the areas south of Michigan suggest that fishers either recolonized from a different area or are the progeny of a remnant population.
Investigators: 
nweld
Associates: 
wittjill
Status of Research Project: 
Active
Years Active: 
2022
Methods: 
Objective 1: Identify current distribution of Fisher in the Lower Peninsula Our first objective is to assess fisher presence and distribution throughout the Lower Peninsula of Michigan. Fisher presence in this project will be detected using hair snares. Hair snares are a non-invasive method of sampling because they do not require researchers to interact with the fisher directly. However, they do allow for the collection of hair follicles that can be used to identify fisher using a DNA sample. The hair snares are made up of six-inch and eight-inch diameter corrugated drainage pipes. Each sample site will have one six-inch and one eight-inch snare. One side of the pipe is blocked off by a piece of cardboard that holds a wire with a piece of meat hanging from it. The pipe is placed on a tree a couple feet off the ground with a cord so that the open part of the pipe faces downwards. In this position, foraging fishers can climb into the opening to reach the meat. When they enter the pipe, there are wooden rods that go through one side of the pipe and out of the other. These rods are covered in tape with the sticky side out. Fishers must work around the rods to reach the meat at the top and the tape traps hairs from the animal which can then be collected. Hair snares will be placed in areas with potentially suitable fisher habitat. Sampling areas were determined using parameters, described below, derived using Geographic Information Systems (GIS). After generating a grid composed of cells seven km2 across the northern Lower Peninsula, any cells containing 60 percent or greater of forest cover will have a snare placed in the middle of it. Cells with 60 percent or greater of forest cover are targeted in this study because of fisher’s association with structurally complex forested habitat with little open areas. For our area of interest, there are 774 cells that fit within the criteria as possible snare sites. Of these 774 possible cells, we used a random function and received an output of 400 cells for sampling to fit into our fieldwork timeline. After collection, genetic methods that can confirm the hair belonged to fisher include mitochondrial DNA fragment lengths and/or microsatellite analysis. We have developed primers to selectively amplify the D-loop of mitochondrial DNA of fishers and martens. 1 guard root hair/5 underfur hairs (De Barba et al. 2014) or 10-12 hairs (Mazzola – unpublished) will be needed for DNA extraction to provide enough genetic material. Samples that do not have a sufficient number of hairs will be excluded from further analysis. DNA will be extracted from hairs using a standard phenol-chloroform extraction technique or by QIAGEN DNeasy extraction kits. The extracted DNA will be kept at -20 degrees Celsius until further analysis is performed. DNA will then be amplified by Polymerase Chain Reaction (PCR) using primers for multiple microsatellite loci previously used in fisher and other mustelid research (De Barba et al. 2014). PCR products will then be run electrophoretically on a gel to visualize the samples. After, the genotypes/alleles will be resolved using GENOTYPER software or GeneImagIR software (De Barba et al. 2014). We have also developed qPCR primers to allow us to confirm whether samples we have collected are fisher or marten without sending products to the lab for confirmation. From these genetic methods we can isolate individual fisher and plot points on a map based on where the hair was collected. These points can be used to generate a current distribution map of fisher in the Lower Peninsula. Depending on the number of samples we are able to collect over our study area, we will be able to make assessments of the population characteristics within the Lower Peninsula using DNA microsatellite analysis. Objective 2: Identify the Genetic Origin of Fisher in the Lower Peninsula We can use DNA from fisher hair for a microsatellite analysis, a genetic fingerprint for individual fisher. We will use microsatellite analysis to determine the frequency of alleles at known fisher loci within our sample population. We can then compare the microsatellite loci of fishers in the Lower Peninsula to other populations of fisher. The populations we will be comparing the alleles found in Lower Peninsula fisher to are those found in the Upper Peninsula, the Canadian province Ontario, and fisher samples pre-disturbance in the Lower Peninsula. Fisher present in the Upper Peninsula should have alleles from animals that were captured in Wisconsin for reintroduction. Genetic material will be gathered from preserved specimens, DNA samples, and pelts of fishers that were trapped in the Lower Peninsula before they were thought to be extirpated, and recently trapped fisher from the Upper Peninsula. Fisher colonizing the Lower Peninsula should be closely related to the population the individuals are colonizing from. Fst values show the proportion of genetic variance within a subpopulation compared to the total genetic variance (Ts). Fst values range from 0 to 1. Values close to 0 indicate high probability of identity by descendent while values closer to 1 indicate higher degrees of differentiation between populations. If values are significantly different from 0 when comparing the genetic variance of fisher in the Lower Peninsula than the Upper Peninsula, we would expect that the fisher in the Lower Peninsula are descended from a remnant population. Furthermore, we would expect that fisher in the Lower Peninsula are not significantly different from 0 when compared to historical samples. Conversely, if the values are not significantly different than 0 for the comparison between Lower Peninsula fisher and Upper Peninsula fisher, we would expect Lower Peninsula fisher to be significantly different than 0 compared to historical samples (Greenhorn et al. 2018). Using the program STRUCTURE, we can calculate Fst values and find population clusters to determine which population fishers in the Lower Peninsula originated from.