Salinity and temperature tolerance of the invasive freshwater gastropod <i>Tarebia granifera</i>

Abstract

Invasive aquatic species, such as the gastropod Tarebia granifera, can cause ecological disturbances and potentially reduce biodiversity by displacing indigenous invertebrates. In South Africa, T. granifera was first recorded in an estuarine environment in the St Lucia Estuary. Its tolerance to salinity and temperature was investigated through the experimental manipulation of these factors. T. granifera can tolerate temperatures between 0 ºC and 47.5 ºC, allowing it to survive high temperature extremes. The species may also survive cold snaps and invade higher altitude areas. More remarkably, this snail survives high salinity for a relatively long time, as LS 50 (lethal salinity for 50% of the population) was reached at 30 psu over 65-75 days. However, higher salinity adversely affected the T. granifera population. Snails acclimated to freshwater conditions and suddenly transferred to 30 psu experienced 100% mortality within 48 h. Snail activity also declined with increasing salinity. T. granifera's environmental tolerance and parthenogenetic characteristics are the keys to successful introduction and establishment. Therefore, the management of T. granifera may prove difficult in the short to medium term. The present findings constitute a contribution to the knowledge of biological invasions in Africa and to the understanding of estuarine invasions by T. granifera.

Gross mismatch between thermal tolerances and environmental temperatures in a tropical freshwater snail: Climate warming and evolutionary implications

“…In contrast to the findings that upper TSMs for equatorial lizards and insects vary in breadth from a few degrees to < 12ºC Kellerman et al, 2012;Logan et al, 2013), our assessment for the freshwater snail Clea nigricans suggests it possesses a TSM for heating of approximately 20ºC. A similar value was obtained for the lower TSM for cooling (around 20ºC) in this snail, in accordance with other gastropods from lowland warm temperate and subtropical regions and other tropical shallow marine molluscs, which have thermal tolerances distinctly unrelated to and well below habitat thermal minima (Davenport and Wong, 1992;Lai et al, 2011;Miranda et al, 2010). These contradictory circumstances for C. nigricans reflect the lack of information and poor current understanding of the evolution of thermal tolerance in land dwelling (freshwater and terrestrial) gastropods.…”

“…In the first instance, the family to which Clea belongs (Buccinidae) is among several present-day tropical marine neogastropod lineages which extend geographical distributions into cool temperate and polar regions (Cooke, 1895;Crame, 2013), and notably, some modern tropical and subtropical lowland taxa survive exposure to temperatures as low as, or below the freezing point (Miranda et al, 2010;Sinclair et al, 2004). On the other hand, although minimum temperatures in lowland tropical marine and terrestrial ecological systems have probably not fallen much below 20°C for vast geological timeframes (Araujo et al, 2013), the forested lotic systems that C. nigricans occupies potentially become much cooler at higher altitudes, presenting the opportunity for cold tolerance to evolve within its lotic environment.…”

Salinity adaptation of the invasive New Zealand mud snail (Potamopyrgus antipodarum) in the Columbia River estuary (Pacific Northwest, USA): physiological and molecular studies

“…There are very few reports of freshwater aquatic organisms adapting to and colonizing habitats with significantly higher salinities than their original habitat. P. antipodarum and Tarebia granifera (Thiaridae: Mollusca; a freshwater snail that has invaded estuarine systems in South Africa and by accounts has a similar history to P. antipodarum) are species capable of this transition (Jacobsen and Forbes 1997;Costil et al 2001;Alonso and Castro-Diéz 2008;Miranda et al 2010). Given the high degree of adaptability, the NZMS could provide an exceptional model for non-native invasion with regard to the geographic range and the scope of different aquatic habitats it encompasses.…”

Chemical Cues Released by an Alien Invasive Aquatic Gastropod Drive Its Invasion Success

“…T. granifera has however not yet been found at Charter’s Creek (average salinity 4.0) on the western shore of the South Lake, while the salinity (54.4) at Lister’s Point in False Bay is well beyond its physiological tolerance [32].…”

“…The non-native species, Tarebia granifera , despite being considered a freshwater caenogastropod, has a remarkable tolerance for moderately saline conditions of up to 30 [32] and has thus become successfully established in areas of the St Lucia Narrows (average salinity 13.8), as well as Catalina Bay (average salinity 3.6). T. granifera has however not yet been found at Charter’s Creek (average salinity 4.0) on the western shore of the South Lake, while the salinity (54.4) at Lister’s Point in False Bay is well beyond its physiological tolerance [32].…”