Epibiotic pressure contributes to biofouling invader success

Abstract

Reduced competition is a frequent explanation for the success of many introduced species. In benthic marine biofouling communities, space limitation leads to high rates of overgrowth competition. Some species can utilise other living organisms as substrate (epibiosis), proffering a competitive advantage for the epibiont. Additionally, some species can prevent or reduce epibiotic settlement on their surfaces and avoid being basibionts. To test whether epibiotic pressure differs between native and introduced species, we undertook ex situ experiments comparing bryozoan larval settlement to determine if introduced species demonstrate a greater propensity to settle as epibionts, and a reduced propensity to be basibionts, than native species. Here we report that introduced species opportunistically settle on any space (bare, native, or introduced), whereas native species exhibit a strong tendency to settle on and near other natives, but avoid settling on or near introduced basibionts. In addition, larvae of native species experience greater larval wastage (mortality) than introduced species, both in the presence and absence of living substrates. Introduced species’ ability to settle on natives as epibionts, and in turn avoid epibiosis as basibionts, combined with significantly enhanced native larval wastage, provides a comprehensive suite of competitive advantages contributing to the invasion success of these biofouling species.

Body condition and energy content of the shore crabCarcinus maenasL. in a temperate coastal system: the cost of barnacle epibiosis

“…Most epibiont species do not settle exclusively on one host species or exhibit obligate epibiosis (Wahl & Mark 1999;Leonard et al 2007;Fernandez-Leborans 2010). In the Wadden Sea, epibiosis by B. crenatus also occurs on the blue mussel Mytilus edulis, albeit to a lesser extent (10% of subtidal mussels, Buschbaum & Saier 2001), and on the periwinkle Littorina littorea, where it can affect 86% of the population (Buschbaum & Reise 1999).…”

“…Dealing with epibiosis generally involves trade-offs between tolerance and investment into defence, which utilises resources of the host (Aucker et al 2004;Leonard et al 2007). Often costs of epibionts outweigh their benefits for the basibiont (eg, Wahl 1989Wahl , 1997Becker et al 2000;Buschbaum & Saier 2001).…”

Marine Biosecurity Crisis Decision-Making: Two Tools to Aid “Go”/“No Go” Decision-Making

“…They are a diverse group with at least 131 recognized families in the world. Marine bryozoa were selected as test case taxa because: (1) they have a long fossil history, which provides a well-defined geographic record (e.g., McKinney, 1986;Smith, 1995;Gordon, 1999;Hageman et al, 2000;Amini et al, 2004); (2) both the fossil and recent bryozoan fauna are relatively well studied (e.g., Ryland, 1977;Bock, 1982;Gordon, 1999;Campbell et al, 2003;Barnes and Griffiths, 2008;Tilbrook, 2012); (3) they are fouling organisms that are associated with a number of different transport/dispersal vectors: biofouling, ballast water, and mariculture (Cariton and Geller, 1993;Gollasch, 2002;Godwin, 2003;Campbell et al, 2004Campbell et al, , 2017Hewitt et al, 2004;Levings et al, 2004;Piola et al, 2009); and (4) they have a demonstrable invasion history (e.g., Cohen and Carlton, 1995;Hewitt, 2002;Hewitt et al, 2004;Mackie et al, 2006Mackie et al, , 2012Leonard et al, 2017). We selected the target species for this analysis from the bryozoan species that were collected and identified from the Australian national port surveys that occurred from 1995 to 2001 (e.g., Hewitt et al, 1997aHewitt et al, ,b, 1999Hewitt et al, , 2000Hewitt et al, , 2004Hewitt and Campbell, 2001;Hewitt, 2002).…”

Epibionts in artificial collectors / Epibiontes en colectores artificiales

“…Epibiosis is a very common phenomenon in marine and estuarine environments, being observed in various substrates, culture structures, ship hulls, oil platforms, mangrove roots and different solid environments, which allow the fixation of organisms (Mol et al 2009;García 2010;Leonard et al 2017), with the use of artificial collectors being the most appropriate tool to study the colonization patterns of benthic communities (Kaufman et al 1992;Mendo et al 2011).Therefore, the identification and quantification of epibionts in a given area, provides important information on the abundance and reproductive behavior of the species and also allows to know the reproductive dynamics of organisms (Leonard et al 2017;Strain et al 2020). This information also helps to establish strategies for the conservation, management and repopulation of organisms, for the recovery of their populations; it also helps to identify species of commercial importance and with cultivation projections.…”