InvasiBES: Understanding and managing the impacts of Invasive alien species on Biodiversity and Ecosystem Services

Invasive Alien Species (IAS) are amongst the most significant drivers of species extinction and ecosystem degradation, causing negative impacts on ecosystem services and human well-being. InvasiBES, a project funded by BiodivERsA-Belmont Forum for 2019–2021, will use data and models across scales, habitats and species to understand and anticipate the multi-faceted impacts of IAS and to provide tools for their management. Using Alien Species Narratives as reference, we will design future intervention scenarios focused on prevention, control and eradication of IAS in Europe and the United States, through a participatory process bringing together the expertise of scientists and stakeholders. We will also adapt current impact assessment protocols to assess both the detrimental and beneficial impacts of IAS on biodiversity and ecosystem services. This information will then be combined with maps of the potential distribution of Invasive Species of Interest in Europe under current and future climate-change scenarios. Likewise, we will anticipate areas under risk of invasion by range-shifting plants of concern in the US. Finally, focusing on three local-scale studies that cover a range of habitats (freshwater, terrestrial and marine), invasive species (plants and animals) and ecosystem services (supporting, provisioning, regulating and cultural), we will use empirical field data to quantify the real-world impacts of IAS on biodiversity and ecosystem services and calculate indicators of ecosystem recovery after the invader is removed. Spatial planning tools (InVEST) will be used to evaluate the costs and benefits of species-specific intervention scenarios at the regional scale. Data, models and maps, developed throughout the project, will serve to build scenarios and models of biodiversity and ecosystem services that are relevant to underpin management of IAS at multiple scales

Impacts of climate change on marine species invasions in northern hemisphere high-latitude ecosystems

High-latitude marine ecosystems have experienced fewer species invasions than temperate marine ecosystems, a discrepancy that may be attributed to barriers such as low propagule pressure, extreme and seasonal abiotic conditions, and biotic resistance of relatively intact communities. Each of these barriers is being affected by climate change and increasing human activity in high-latitude (>55º N) areas. We reviewed the evidence for each of these barriers limiting species invasion in high-latitude areas in the northern hemisphere. Based on records from government documents of high‐latitude countries, non-native species appear to be increasing in number (in Denmark and the United States) although there remains a paucity of data on invasive species establishment for high-latitude regions. Future study is needed to identify the drivers and impacts of invasions at high latitudes so that managers looking to prevent invasions can focus their efforts on bolstering barriers to invasion in these unique ecosystems

Effects of experimental warming and CO₂ addition on tide pools.

<p>(a) Effects of warming on tide pool temperatures depended on air temperature. Experimental warming increased pool temperatures on cooler days (≤ 15°C) but not when air temperatures were ≥ 15°C. Values are the 90^th percentiles of air temperatures (x-axis) and difference between 90^th percentile temperatures in warmed <i>vs</i>. ambient pools (y-axis) on each day. Statistical significance is indicated: p < 0.05 (*), p > 0.05 (NS). (b) Compared to pools at ambient CO₂ levels, experimental manipulations led to decreases in average pH (total hydrogen ion scale). Values are means ± SE.</p

Relative cover of sessile species in experimental tide pools.

<p>The red alga <i>Odonthalia floccosa</i> was the most abundant species, covering 48.27% (± 0.06 SE) of available space. 17.49% (± 0.04 SE) of space was bare. Values are mean percent cover across the n = 20 pools.</p

Seawater carbonate chemistry and net community production and net ecosystem calcification in tide pools

Predicting the impacts of ocean acidification in coastal habitats is complicated by bio-physical feedbacks between organisms and carbonate chemistry. Daily changes in pH and other carbonate parameters in coastal ecosystems, associated with processes such as photosynthesis and respiration, often greatly exceed global mean predicted changes over the next century. We assessed the strength of these feedbacks under projected elevated CO2 levels by conducting a field experiment in 10 macrophyte-dominated tide pools on the coast of California, USA. We evaluated changes in carbonate parameters over time and found that under ambient conditions, daytime changes in pH, pCO2, net ecosystem calcification (NEC), and O2 concentrations were strongly related to rates of net community production (NCP). CO2 was added to pools during daytime low tides, which should have reduced pH and enhanced pCO2. However, photosynthesis rapidly reduced pCO2 and increased pH, so effects of CO2 addition were not apparent unless we accounted for seaweed and surfgrass abundances. In the absence of macrophytes, CO2 addition caused pH to decline by ∼0.6 units and pCO2 to increase by ∼487 µatm over 6 hr during the daytime low tide. As macrophyte abundances increased, the impacts of CO2 addition declined because more CO2 was absorbed due to photosynthesis. Effects of CO2addition were, therefore, modified by feedbacks between NCP, pH, pCO2, and NEC. Our results underscore the potential importance of coastal macrophytes in ameliorating impacts of ocean acidification