Future Aquatic Invaders of the Northeast U.S.: How Climate Change, Human Vectors, and Natural History Could Bring Southern and Western Species North
Researchers will evaluate the potential of aquatic species to invade the Northeast U.S. Following the identification of appropriate target species by regional stakeholders, researchers will gather data from the NAS database and develop models to determine habitat suitability for each species.
The Science Issue and Relevance: Invasive species are one of the greatest threats to U.S. biodiversity, and aquatic invasions have cost the global economy US$345 billion with the largest percent in North America. Climate change is expected to further facilitate the spread of invasive species and has been identified as a major concern for natural resources managers. Despite this, a lack of information has limited the consideration of climate change in decision-making and applied management. To address this issue, this project is creating realistic future scenarios of expansion of southern and western aquatic nonnative species into Northeast waterbodies for stakeholder-identified priority invasive aquatic species. Using habitat suitability models based on current and future climate conditions in the region and analysis of known pathways of spread, this effort will develop risk scores for the spread and establishment of impactful aquatic invaders into the Northeast. Rather than using standard sets of readily available predictors commonly applied across suites of species, which may not capture factors that are physiologically limiting for a species, we are using predictors biologically and individually relevant to species traits and life histories including hydrologically relevant information. The anticipated products include 1) an expert-elicited list of 110 priority plant, fish, and invertebrate invasive species; 2) pathway risk analysis scores for each species; 3) digital maps of potential future habitat suitability; and 4) future risk scores for each target invasive species. These digital maps will be integrated into the USGS Nonindigenous Aquatic Species (NAS) Database (https://nas.er.usgs.gov), where they will be interactive and scalable to hydrologically relevant landscape features. This focus on fine-scale hydrologic connectivity will provide stakeholders in the Northeast with discrete areas to focus risk management efforts.
Methodology for Addressing the Issue: We will evaluate the potential of the species chosen by stakeholders to invade the Northeast under future climate scenarios. Determining the list of target species via a workshop with regional stakeholders will ensure that species of greatest management concern are evaluated. Data on current invasive species distributions within the contiguous U.S. will come from the NAS database, EDDMapS, iMapsInvasives and other invasive species databases. We will then develop models to determine habitat suitability for each species and project these models onto future environmental conditions. Habitat suitability models relate environmental conditions thought to control a species’ distribution at known locations to develop mathematical relationships that can be used to predict suitability across a landscape. Pathways, how species are transported from one location to another, are an important factor in assessing the risk of an invasive species spread to uninvaded suitable habitat. This movement can be from natural distribution through connected aquatic systems or through intentional or unintentional human mediated movement. To aid in the evaluation of the potential movement of invasive species into the Northeast, we will utilize a modified version of the U.S. National Invasive Species Council’s (NISC) pathway risk analysis tool to assign a risk score to the known or potential pathways through expert consensus and will be used to build a pathway risk index.
Future Steps: The USGS NAS Database and Invasive Species Habitat Tool, or INHABIT, have been created for long-term useability. The NAS Database was established in 1990 and has been continuously tracking all non-native aquatic species for the U.S. USGS has made a long-term commitment to supporting the program. The proposed project will be integrated into the NAS Database and maintained with that same goal in mind. We plan to conduct annual reviews to see if models should be revised based on the amount and distribution of new occurrence data of all modeled species, newly available predictor data (e.g., climate, habitat), and stakeholder feedback. If the models need to be updated, we will take that step as our program maintenance. The initial investment to determine a workflow for occurrence data, predictor production, modeling, and post-processing to produce end products is the most time consuming and cost-intensive part. Refitting models with updated data is comparatively fast and straightforward if the same workflow is utilized. There would be value in looking at the potential of completely revising the models to add new species or change the modeling process 3-5 years from the completion of the project. Gaps in knowledge of aquatic species’ physiological tolerances would be explicit during the model review process, which could lead to research proposals to fill those gaps.
Researchers will evaluate the potential of aquatic species to invade the Northeast U.S. Following the identification of appropriate target species by regional stakeholders, researchers will gather data from the NAS database and develop models to determine habitat suitability for each species.
The Science Issue and Relevance: Invasive species are one of the greatest threats to U.S. biodiversity, and aquatic invasions have cost the global economy US$345 billion with the largest percent in North America. Climate change is expected to further facilitate the spread of invasive species and has been identified as a major concern for natural resources managers. Despite this, a lack of information has limited the consideration of climate change in decision-making and applied management. To address this issue, this project is creating realistic future scenarios of expansion of southern and western aquatic nonnative species into Northeast waterbodies for stakeholder-identified priority invasive aquatic species. Using habitat suitability models based on current and future climate conditions in the region and analysis of known pathways of spread, this effort will develop risk scores for the spread and establishment of impactful aquatic invaders into the Northeast. Rather than using standard sets of readily available predictors commonly applied across suites of species, which may not capture factors that are physiologically limiting for a species, we are using predictors biologically and individually relevant to species traits and life histories including hydrologically relevant information. The anticipated products include 1) an expert-elicited list of 110 priority plant, fish, and invertebrate invasive species; 2) pathway risk analysis scores for each species; 3) digital maps of potential future habitat suitability; and 4) future risk scores for each target invasive species. These digital maps will be integrated into the USGS Nonindigenous Aquatic Species (NAS) Database (https://nas.er.usgs.gov), where they will be interactive and scalable to hydrologically relevant landscape features. This focus on fine-scale hydrologic connectivity will provide stakeholders in the Northeast with discrete areas to focus risk management efforts.
Methodology for Addressing the Issue: We will evaluate the potential of the species chosen by stakeholders to invade the Northeast under future climate scenarios. Determining the list of target species via a workshop with regional stakeholders will ensure that species of greatest management concern are evaluated. Data on current invasive species distributions within the contiguous U.S. will come from the NAS database, EDDMapS, iMapsInvasives and other invasive species databases. We will then develop models to determine habitat suitability for each species and project these models onto future environmental conditions. Habitat suitability models relate environmental conditions thought to control a species’ distribution at known locations to develop mathematical relationships that can be used to predict suitability across a landscape. Pathways, how species are transported from one location to another, are an important factor in assessing the risk of an invasive species spread to uninvaded suitable habitat. This movement can be from natural distribution through connected aquatic systems or through intentional or unintentional human mediated movement. To aid in the evaluation of the potential movement of invasive species into the Northeast, we will utilize a modified version of the U.S. National Invasive Species Council’s (NISC) pathway risk analysis tool to assign a risk score to the known or potential pathways through expert consensus and will be used to build a pathway risk index.
Future Steps: The USGS NAS Database and Invasive Species Habitat Tool, or INHABIT, have been created for long-term useability. The NAS Database was established in 1990 and has been continuously tracking all non-native aquatic species for the U.S. USGS has made a long-term commitment to supporting the program. The proposed project will be integrated into the NAS Database and maintained with that same goal in mind. We plan to conduct annual reviews to see if models should be revised based on the amount and distribution of new occurrence data of all modeled species, newly available predictor data (e.g., climate, habitat), and stakeholder feedback. If the models need to be updated, we will take that step as our program maintenance. The initial investment to determine a workflow for occurrence data, predictor production, modeling, and post-processing to produce end products is the most time consuming and cost-intensive part. Refitting models with updated data is comparatively fast and straightforward if the same workflow is utilized. There would be value in looking at the potential of completely revising the models to add new species or change the modeling process 3-5 years from the completion of the project. Gaps in knowledge of aquatic species’ physiological tolerances would be explicit during the model review process, which could lead to research proposals to fill those gaps.