Assessment of bioinvasion impacts on a regional scale: a comparative approach

Abstract

This paper presents an overall bioinvasion impact assessment on the scale of a large marine region-the Baltic Sea, as defined by the Helsinki Commission. The methodology is based on a classification of the abundance and distribution range of alien species and the magnitude of their impacts on native communities, habitats and ecosystem functioning aggregated in a ''Biopollution Level'' index (BPL) which ranges from 'no impact' (BPL = 0) to 'massive impact' (BPL = 4). The assessment performed for nine Baltic sub-regions revealed that documented ecological impact is only known for 43 alien species out of 119 registered in the Sea. The highest biopollution (BPL = 3, strong impact) occurs in coastal lagoons, inlets and gulfs, and the moderate biopollution (BPL = 2)-in the open sea areas. The methodology was also used to classify species into alien (BPL = 0) versus 'impacting' species (BPL [ 0), which can be divided into 'potentially invasive' (BPL = 1) and 'invasive' (BPL [ 1) ones. No clear correlation between the number of established alien and impacting species was found in the sub-regions of the Baltic Sea. The methodology, although requiring a substantial research effort, proved to be useful for interregional comparisons and evaluating the bioinvasion effects of individual alien species.

Metabarcoding approach for nonindigenous species surveillance in marine coastal waters

“…1) to 5 non-indigenous species considered as invasive in the Baltic Sea with reported impacts on biodiversity and ecosystem functioning (Zaiko et al 2011). Despite higher LNM sampling effort in KS and PA (Table 1), most of NIS in the samples were identified exclusively by the HTS, except for Ponto-Caspian water flea Cercopagis pengoi which was also morphologically detected from the LNM samples (Table 2).…”

Spatial distribution and population characteristics of the invasive cladoceran Cercopagis pengoi in the Polish coastal zone seven years after the first record

“…This phenomenon has been most frequently observed in coastal areas, bays and estuaries (Leppäkoski & Mihnea 1996, Leppäkoski et al 2002, Zaiko et al 2011. It is only in the last decade that some new non-indigenous species (NIS) have been reported in the Southern Baltic.…”

Invasive ecosystem engineers and biotic indices: Giving a wrong impression of water quality improvement?

“…As it was previously reported, zebra mussels are generally associated with increased benthic macrofauna abundance, species richness and decreased community evenness (Ricciardi et al 1997, Zaiko et al 2009, Atalah et al 2010. Being one of the most abundant and widely distributed IAS in the oligohaline regions of the Baltic Sea (Zaiko et al 2011, Fenske et al 2013) zebra mussels produce dense colonies and beds of empty shells forming patches of high biodiversity and facilitating establishment of native and non-indigenous species (Zaiko et al 2007(Zaiko et al , 2009. It has been shown recently that some eutrophication-related metrics (e.g.…”

“…However an impact of invasive alien species (IAS) present in the considered ecosystem has been largely overlooked by researchers so far. IAS may induce multiple important alterations in the recipient ecosystem including changes in structure and distribution of native species assemblages, habitat properties, food web structure and biogeochemical processes (Elliott 2003, Reise et al 2006, Zaiko et al 2011. Therefore, it is likely that impacts of other stressors may be surpassed and the correspondent ecosystem responses masked ).…”