Wildlife Management Institute

WMI Outdoor News Bulletin Working Group Taking a Closer Look at Allegheny Woodrats
Working Group Taking a Closer Look at Allegheny Woodrats PDF Print E-mail

image of Allegheny Woodrat, Credit: Joe Kosack/PGC PhotoMany small, uncharismatic nongame species, especially those not recognized with economic or social value, have received much less conservation and management concern than charismatic species that capture the public’s attention.  The Allegheny woodrat (Neotoma magister) is one such species. Allegheny woodrats are small rodents (but not rats!) about the size of gray squirrels that inhabit talus slopes, boulder fields, caves, and cliffs in hardwood forests along the Appalachian Mountains in the eastern United States.  Because the areas they inhabit are so isolated, they generally show little fear of humans, and they have a penchant for collecting novel objects – a trait that gave rise to their nickname “packrat.” As habitat specialists, however, Allegheny woodrats probably were never very abundant, and in recent decades they have experienced steep population declines, particularly in the northern and western periphery of their historical range. They are extinct in New York and barely hanging on in several other northern states.

The Allegheny woodrat working group is composed of USGS Cooperative Research Unit scientists, university researchers, and state biologists, who are collaborating to develop a structured decision model to identify management strategies to encourage conservation and recovery of woodrat populations. Many woodrat populations that used to be robust now have winked out, and remaining populations tend to be small and losing genetic diversity. The reasons for the population declines include predation, disease, habitat fragmentation, and changes in forest structure and species composition.  Several states have identified the Allegheny woodrat as critically imperiled or in need of restoration, and even in states where woodrat populations are believed to be stable there is recognition that long-term conservation planning is needed.

Until recently, however, there has been little focus on inter-state collaboration to develop management guidelines. Several possible management alternatives have been proposed, including habitat manipulations to increase food supply or reduce predation risk, management of disease risk, supplemental feeding, and translocations – but which strategy works best, in which situation? And what are the key ecological relationships that influence woodrat population dynamics? How might proposed management actions influence those relationships? Developing a decision model that accounts for alternative hypotheses about potential population responses is a primary goal of this working group. Such a decision model can be used to test and compare potential management strategies and adapt management plans to employ those actions that are most effective. Such an approach also has potential to provide a better understanding of the basic ecology of woodrats.

One important objective of the working group is to identify a monitoring strategy to evaluate population responses to management actions. Then the outcomes of individual state management activities can be used collectively to inform future management decisions. Also, the working group has identified existing data that can be used to collaborate on meta-analyses and begin to investigate which ecological factors are most important to population recovery. These efforts will also help prioritize future research aimed at reducing uncertainties about woodrats and the factors that most influence population dynamics.

The main goal of the working group is to ensure the long-term viability of a species that, if not charismatic, is nonetheless quite fascinating. Given the limited funds that states typically have to devote to management of relatively obscure nongame species like Allegheny woodrats, it is important that management actions be as cost-effective as possible. A decision model that identifies which management strategies are most likely to be successful given site-specific attributes and the uncertainty about the response by woodrat populations will allow states to get the most bang for their buck. Assessing long-term viability also requires long-term monitoring, and the decision model will help states to prioritize monitoring efforts by focusing on the specific data needed to provide feedback about population response to management. It is this directed monitoring and feedback that will help managers better understand woodrat ecology – and then management can be adaptive. The collaboration and data sharing by scientists and managers from multiple states is an important step forward to developing a decision model and implementing such a management strategy that is cost-effective and consistent throughout the range of the species. This is probably the best hope to keep Allegheny woodrats from disappearing forever from eastern deciduous forests.

Although the Allegheny woodrat is not a charismatic species, it can serve as the proverbial canary in the coal mine. In Pennsylvania, 16 species of special concern are associated with the same habitats used by Allegheny woodrats.  Thus, Allegheny woodrats can serve as an umbrella species whose status should serve as an indication of the resilience of surface rock communities and intact forests.  Optimal management of woodrats has potential to provide benefits for a diverse wildlife community.

By: Allegheny Woodrat Management Team