Exotic invasive species pose a significant threat to species of greatest conservation need (SGCN) throughout the Northeast in a number of ways. Impacts may be direct (affecting individual health or productivity) or indirect (affecting habitat and/or ecosystem processes) or both. State wildlife action plans (SWAP) have identified wildlife species within each state that warrant some level of management concern. Causes for concern vary by species and typically loss of habitat, pollution, and other stressors are listed as contributors to population decreases. In some cases, invasive species have been specifically identified as impacting subsets of SGCNs within states but to date, there has been no assessment of the invasive species posing the greatest potential threat to SGCNs at the regional level.
The original goal of this project was to produce a list of invasive species that posed the most significant threat to SGCNs in the Northeast Region. However, during the process of completing the project it became evident that the true value in this effort lies in the data assembled and the ability for future users to customize it for their specific needs. Therefore, the goal of this project was amended to focus on the provision of these data tables provided below and a process for modifying them to allow users to modify them and generate lists reflecting their own importance criterion. There are a number of different ways to evaluate the impacts of invasives. These metrics can be as simple as the number of SGCNs impacted by each invasive, or can be more complex incorporating invasive characteristics, impacts, or weighting values. We compiled several metrics that could provide users with a way to develop ranked lists either taken individually or used together (e.g., sum of ranks). Users should understand how each metric is calculated and what information is included in order to use the most appropriate metric for their needs. The metrics can be easily modified in MS Excel to produce custom values for specific needs.
This project was completed in January 2012. The final report and appendices A-D of data tables are provided below. The final report provides background information on how these data tables of SGCN and invasive species were developed and how they should be interpreted for prioritizing and ranking invasive species threats to SGCNs. Also provided is an example of how this information can be used to generate specific ranked lists of invasive species for terrestrial species in Pennsylvania. The example files contain a word document that walks the user through the process of using the 3 example excel files.
Exotic invasive species pose a significant threat to species of greatest conservation need (SGCN) throughout the Northeast in a number of ways. Impacts may be direct (affecting individual health or productivity) or indirect (affecting habitat and/or ecosystem processes) or both.
State wildlife action plans (SWAP) have identified wildlife species within each state that warrant some level of management concern. Causes for concern vary by species and typically loss of habitat, pollution, and other stressors are listed as contributors to population decreases. In some cases, invasive species have been specifically identified as impacting subsets of SGCNs within states but to date, there has been no assessment of the invasive species posing the greatest potential threat to SGCNs at the regional level.
The original goal of this project was to produce a list of invasive species that posed the most significant threat to SGCNs in the Northeast Region. However, during the process of completing the project it became evident that the true value in this effort lies in the data assembled and the ability for future users to customize it for their specific needs. Therefore, the goal of this project was amended to focus on the provision of these data tables and a process for modifying them to allow users to modify them and generate lists reflecting their own importance criterion.
This report will provide background information on how these data tables were developed and how they should be interpreted for prioritizing and ranking invasive species threats to SGCNs. This report will provide background information on how the lists of SGCNs and invasive species were compiled and attributed. We will also provide an example of how this information can be used to generate specific ranked lists of invasive species.
This example is supplied to illustrate how to use the invasive species and species of greatest conservation need (SGCN) tables to produce a ranking for the invasive species posing the greatest threat to SGCNs in Pennsylvania. This stepwise process can be used for any subset of the data provided.
We will draw upon the information provided in the final report and tables accompanying this exercise. The terms and background used in this example are explained in detail in the final report, and we will assume users are familiar with this document before using this example. If terms or processes are unclear, please refer back to the final report.
All operations used will be completed using Microsoft Excel and the tools and functions included in it with the exception of one custom macro contained in the file supplied (Note: in order to use this macro, macros must be enabled upon opening the file when prompted) entitled “Appendix C – Interaction Tables.xls”. Wherever possible, specific formulas and steps will be provided in detail. Some functions such as “Copy/Paste Special” will not be explained in detail. These are simple functions to master in Excel.
In all cases, we recommend making changes to copies of the original data when completing custom analyses. This is good practice and will ensure the integrity of the original dataset for subsequent analyses.