Can biotic resistance be utilized to reduce establishment rates of non-indigenous species in constructed waters?

Abstract

Understanding the mechanisms that facilitate establishment of non-indigenous species is imperative for devising techniques to reduce invasion rates. Passively dispersing non-indigenous organisms, including zooplankton, seemingly invade constructed waters (e.g., ornamental ponds, dams and reservoirs) at faster rates than natural lakes. A common attribute of these invaded water bodies is their relatively young age, leading to the assertion that low biotic resistance may lead to their higher vulnerability. Our aim was to determine if seeding of young water bodies with sediments containing diapausing stages of native zooplankton could accelerate community development, leading to greater biotic resistance to the establishment of new species. Twenty outdoor tanks were filled with water (1,400 L) and nutrients added to attain eutrophic conditions. Ten treatment tanks had sediments added, sourced from local water bodies. In the remaining ten, sediments were autoclaved, and received zooplankton via natural dispersal only. In an initial 12 month monitoring period, species richness increased at a greater rate in the treatment tanks (at 12 months average standing richness per tank = 3.8, accumulated richness = 8.2) than control tanks (2.6 and 5.0, P \ 0.05). Treatment tanks developed assemblages with greater proportions of species adapted to pelagic conditions, such as planktonic cladocerans and copepods, while control tanks generally comprised of smaller, littoral dwelling, rotifers. Analysis of similarities indicated community composition differed between the control and treatment groups at 12 months (P \ 0.01). Two copepod, four rotifer and one cladoceran species were intentionally added to tanks at 12 months. In the 3 month post-introduction period, five of these species established populations in the control tanks, while only two species established in the treatment tanks. The calanoid copepod Skistodiaptomus pallidus, for example, a non-indigenous species confined to constructed waters in New Zealand, established exclusively in tanks where native calanoid copepod species were absent (primarily control tanks). Our study suggests that biotic resistance could play an important role in reducing the establishment rate of non-indigenous zooplankton. It also provides evidence that seeding constructed water bodies with sediments containing diapausing eggs of native species may provide an effective management tool to reduce establishment rates of non-indigenous zooplankton.

Aquatic invasive species: challenges for the future

“…A recent study in Mediterranean reservoirs demonstrated that richness of non-native fish was negatively related to richness of the native fish community, indicating the importance of biotic resistance, whereas native fish were mostly affected by the abiotic factors (Clavero et al, 2013). The role of biotic resistance on invasibility of constructed systems has also been demonstrated with zooplankton (Shurin, 2000;Taylor & Duggan, 2012). For instance, in a mesocosm experiment (viewed as a model of a reservoir in the its earlier phase), seeding newly constructed tanks with native species eggs decreased establishment success of invasive zooplankton one year later, relative to tanks without a native assemblage (Taylor & Duggan, 2012).…”

“…The role of biotic resistance on invasibility of constructed systems has also been demonstrated with zooplankton (Shurin, 2000;Taylor & Duggan, 2012). For instance, in a mesocosm experiment (viewed as a model of a reservoir in the its earlier phase), seeding newly constructed tanks with native species eggs decreased establishment success of invasive zooplankton one year later, relative to tanks without a native assemblage (Taylor & Duggan, 2012).…”

A review of potential methods for zooplankton control in wastewater treatment High Rate Algal Ponds and algal production raceways

“…HRAPs are usually in close proximity to other ponds (including maturation ponds), and birds visiting the ponds are the most likely vector of contamination. Man-made water bodies such as wastewater ponds are more readily invaded by zooplankton than natural water bodies, which already have established species capable of efficiently consuming available resources [119][120][121]. A greater understanding of the factors controlling the production and hatching of diapausing eggs is therefore important to design effective zooplankton control strategies.…”

Advancing impact prediction and hypothesis testing in invasion ecology using a comparative functional response approach

“…This may, in part, be due to a lack of rigour in defining these hypotheses (Heger et al 2013) and lack of focus on demographic processes. These two major challenges need to be simultaneously addressed to advance the fundamental science of invasion ecology and to provide practical methodologies that prioritize and mitigate invasion threats by, for example, refining risk assessment protocols (Ricciardi and Rasmussen 1998;Parker et al 1999;Byers et al 2002;Andersen et al 2004;Kumschick et al 2012;Leung et al 2012) and managing biological communities to provide maximum biotic resistance (Taylor and Duggan 2012).…”