Lyons et al. 2020

Species Distribution Models Reveal Present and Future Marine Invasion Hotspots

Lyons, D. A., J. B. Lowen, T. W. Therriault, D. Brickman, L. Guo, A. M. Moore, M. A. Peña, Z. Wang, and C. DiBacco. 2020. Identifying marine invasion hotspots using stacked species distribution models. Biological Invasions 22:3403–3423.

Keywords:

Coastal & marine; Tools & practice; Species distribution models; Climate change responses; Invasive marine species

Summary:

Knowing where invasive species occur is critical to allocating limited resources for early detection and control, yet comprehensive occurrence data is rare, especially in marine systems. Species Distribution Models (SDMs) can help fill in data gaps by predicting where invasive species occur or are likely to establish. SDMs use data on invasive species’ observed occurrence locations, which is often incomplete, and their optimal biophysical conditions. This allows researchers to estimate the distribution of these species at a spatially useful level. The estimates can be combined with climate models to predict future shifts in distribution. Lyons et al. (2020) built and combined SDMs for multiple invasive species in the Northwest Atlantic or Northeast Pacific to identify current hotspots of invasion in each ocean region. Then, they projected the species distributions to 2075 based on climate models assuming greenhouse gas emissions continue to be high. Their models identified many current marine invasion hotspots, including much of the Salish Sea and some of the outer coast of Oregon and Washington. Under climate change, the models predicted some expansion of invasion hotspots in the Northwest Atlantic, but far more dramatic expansion and creation of new hotspots in the Pacific.

Take Home Points:

• Species Distribution Models (SDMs) are sophisticated tools that produce easy-to-interpret outputs from incomplete data, and the resulting maps are intuitive tools for communication.

• Using present-day and predicted climate conditions, combining SDMs for multiple species can help identify invasion hotspots.

• With climate change, current marine invasion hotspots, or areas where more invasive species are expected to occur, are likely to intensify in the Pacific. Many areas of low invasion may increase to moderate invasion.

• Marine invasion hotspots may be more dramatically impacted by climate change in the Pacific versus the Atlantic Ocean.

Management Implications:

• Identifying potential hotspots helps identify areas where invasive species are most likely to cause ecological or socioeconomic harm. 

• Species distribution models can improve efficacy at all stages of decision making. They can help managers identify areas where species are more likely to become established and spread (early detection) and areas at high risk due to climate change. 

• Patterns of current and predicted marine invasive species hotspots do not necessarily closely match areas of high vessel traffic or major ports, which have previously been identified as key vectors of species introduction. Increased attention to other vectors of introduction, such as aquaculture, recreational vessels, oil platforms, trade of live organisms, and fouling (surface attaching) organisms on marine equipment and ship hulls is needed to minimize invasion threats.

This research summary was adapted from NE RISCC by Berlin Nelson.