Impact of three aquatic invasive species on native plants and macroinvertebrates in temperate ponds

Abstract

Biological plant invasions pose a serious threat to native biodiversity and have received much attention, especially in terrestrial habitats. In freshwater ecosystems impacts of invasive plant species are less studied. We hypothesized an impact on organisms from the water column and from the sediment. We then assessed the impact of three aquatic invasive species on the plants and macroinvertebrates: Hydrocotyle ranunculoides, Ludwigia grandiflora and Myriophyllum aquaticum. Our research on 32 ponds in Belgium indicated that the reduction in the native plant species richness was a common pattern to invasion. However, the magnitude of impacts were species specific. A strong negative relationship to invasive species cover was found, with submerged vegetation the most vulnerable to the invasion. Invertebrate richness, diversity and abundance were measured in sediments of invaded and uninvaded ponds along a gradient of H. ranunculoides, L. grandiflora, and M. aquaticum species cover. We found a strong negative relationship between invasive species cover and invertebrate abundance, probably due to unsuitable conditions of the detritus for invertebrate colonization. Taxonomic compositions of aquatic invertebrate assemblages in invaded ponds differed from uninvaded ponds. Sensitive benthos, such as mayflies were completely absent in invaded ponds. The introduction of H. ranunculoides, L. grandiflora, and M. aquaticum in Belgian ponds has caused significant ecological alterations in the aquatic vegetation and the detritus community of ponds.

Restoring macrophyte diversity in shallow temperate lakes: biotic versus abiotic constraints

“…This is for instance observed in restoration projects in shallow eutrophic lakes, where upon the increase of water transparency, fast-growing eutrophic species such as Elodea nuttallii or C. demersum may initially become dominant, leading to a large coverage of macrophytes, but low species diversity . Similarly, the spread of invasive macrophytes can lead to high coverage and large macrophyte biomass, but a low species diversity, as native species may become outcompeted due to shading (Stiers et al, 2011). Nutrient levels in shallow water bodies do affect macrophyte diversity indirectly through changing light conditions, but also directly through the accumulation of toxic substances.…”

Exploring the efficacy of an aquatic invasive species prevention campaign among water recreationists

“…The establishment of aquatic invasive species (AIS) in waterways compromises the biological health (e.g., competition with native species, Stiers et al 2011) and the economic vitality (e.g., loss of valued fisheries; Hinterthuer 2012) of aquatic ecosystems. Given that AIS prevention is less expensive than response (Lovell et al 2006), outreach campaigns, such as the Stop Aquatic Hitchhikers!…”

Native submerged macrophyte distribution in seasonally-flowing, south-western Australian streams in relation to stream condition

“…damselfly nymphs hatching from endophytic eggs). Because plants in this study did not grow in dense beds, the potential negative impacts of dense growth on macroinvertebrates (Suren and Riis 2010;Stiers et al 2011) did not occur, so native submerged macrophyte presence in degraded reaches supported abundant and taxa-rich invertebrate communities.…”

“…In some cases this may cause excessive (prolific, spreading, high density) growth, with potential to impact aquatic fauna through altered assemblage structure (Schultz and Dibble 2012) and increased risk of anoxia (Stiers et al 2011). However, growth response is constrained by flow and substratum characteristics (Riis and Biggs 2001) (Figure 3.1) and will therefore vary between systems.…”