Maps and models of invasive species with a focus on the United States

Commonly observed non-native species in the United States include 2,600 plants, 600 insects, and 100 diseases. However, 8,650 non-native species are listed in the contiguous U.S., 1,250 non- native species are listed in Mexico, and 1,450 non-native species are listed in Canada. Non-native insects not yet present have been identified to damage or kill North American tree species. Non-native species currently may not be invasive, as defined by damage, but some may become invasive in the future. Using compiled datasets for every non-native species with ≥ 400 observations from these lists, it is possible to map and model non-native species observed ranges and potential distributions under current and future climate in North America. Including all of North America is important for detecting species at countries bordering the United States to prevent entry and establishment as a management problem. Additionally, over time, species likely will expand poleward from more southern ranges. Maps of invasion and invasion probability at large extents and multiple temporal resolutions can be used by resource managers as an early warning and detection tool of where and when to expect non-native species to prioritize management strategies aimed at invasive species prevention and control.

This project will:

1. Determine current observed range.
2. Model and map species distributions with variables of current climate (1981–2010), current land cover, and human population density, which is a proxy for flow and propagule pressure of non-native species due to human activities, to provide the best current map and determine the relative influence of population densities. This will help indicate if species have distributed throughout their climate potential or are still being introduced by human activities.
3. Model and map species distributions with only variables of current climate (1981–2010) to determine how much the observed range has filled potential climate space.
4. Predict and map species distributions for near future climate (2011–2041), a timeframe relevant to near-term decision-making, and end-of-century climate (2071–2100) to determine potential shifts and loss and gain of invasive species.
5. Using non-North American observations, which will encompass native ranges, predict and map species distributions in North America for near future climate (2011–2041) and end-of-century climate (2071-2100) as another approach to determine potential distributions in North America. This will help establish if non-native species have adhered to the same climate space in North America as elsewhere, still have space to expand in North America, or have exceeded climate space.

In addition to maps and GIS layers, summary tables will be provided of recorded species detections, recorded species detections that are within a range of distances (for example, 100 miles, 50 miles, 10 miles) for early warning, the area of species presence based on observed ranges, and the potential area for species to be present under current and near future and end-of-century climates by ecoregions, counties, and protected areas, including National Forests and National Grasslands.