Life history and population dynamics of the exotic snail Potamopyrgus antipodarum (Prosobranchia : Hydrobiidae) in Lake Purrumbete, Victoria, Australia

Abstract

The density, population size-structure, and fecundity of the exotic snail Potamopyrgus antipodarum are described, for a period of two years, on two shores subject to different levels of disturbance in Lake Purrumbete. The population dynamics of Potamopyrgus antipodarum showed the same seasonal pattern in the numbers of embryos carried per individual female in both years, but seasonal patterns in density and potential reproductive output of the population differed between shores. Densities of Potamopyrgus antipodarum were high, with a trend for highest densities to occur in spring and summer. The population consisted almost entirely of females, which is indicative of a parthenogenic mode of reproduction. Fecundity was high, with the number of embryos carried per female peaking in spring. In summer, the population was dominated by small individuals, but some small snails were present at all times of the year. Potamopyrgus antipodarum was found to be a very successful invader of Lake Purrumbete, with high densities, high fecundity, parthenogenesis and the presence of embryos throughout the year contributing to this success.

Long-term population fluctuations of the exotic New Zealand mudsnail Potamopyrgus antipodarum and its introduced aporocotylid trematode in northwestern France

“…The lack of sexual reproduction is consistent with what is seen for introduced P. antipodarum from Europe, Australia, and America, where males are rare or completely absent (e.g., Wallace, 1978Wallace, , 1985Hughes, 1996;Schreiber et al, 1998;Gaino et al, 2008;McKenzie et al, 2013;Collado, 2014). increased from March to May in each year, and also increased with snail size, as previously demonstrated (e.g., Winterbourn, 1970;Gérard & Poullain, 2005;Gaino et al, 2008;McKenzie et al, 2013).…”

“…Interestingly and unlike most other bivalves, they also remove bacteria and organic detritus from the sediment by filtering interstitial water and pedal deposit feeding (i.e., a form of deposit feeding using cilia on the foot to collect buried organic matter) (Vaughn & Hakenkamp, 2001 for review). P. antipodarum is a generalist feeder, simultaneously a deposit-feeder, grazer and detritivore, which uses periphytic algae (e.g., green algae, diatoms), bacteria, and detritus, and thus, the same resources as many other macroinvertebrates found in the French stream, including Sphaeriidae (Fenchel, 1975;Haynes & Taylor, 1984;Schreiber et al, 1998;Kerans et al, 2005). Because food limitation is shown to be a e.…”

“…), both adult and newly recruited, growing P. antipodarum were present throughout the year, but without obvious, constrained periods where most recruitment occurred. In general, parthenogenetic forms of P. antipodarum produce offspring throughout the year, with seasonal fluctuations in reproductive output depending on the clonal population considered and environmental conditions such as temperature, hardness (dissolved calcium), phosphorus level, food availability, and population density (e.g., Winterbourn, 1970;Dussart, 1977;Dahl & Winter, 1993;Schreiber et al, 1998;Neiman, 2006Neiman, , 2013Tibbets et al, 2010;McKenzie et al, 2013). Females in Le Petit Hermitage had a higher fecundity in 2013 when population densities were low (from 12 to 48 snails sampled per month) than in 2002 and 2004 when densities were very high (from 1,623 to 2,993 snails per month), although no significant correlation was found between monthly embryo number per adult female and snail abundance.…”

Response of bivalve populations to drying disturbance and life history traits of twoPisidiumspecies (Bivalvia: Sphaeriidae) in a reservoir of the French Upper Rhone river

“…The ability to produce young throughout the year has also been mentioned in Sphaerium and Musculium (Mackie, 1979) and in populations of the gastropod Potamopyrgus antipodarum (Gray), from New Zealand, Australia and Europe (Winterbourn, 1970;Fretter and Graham, 1978;Schreiber et al, 1998). However, in pisidiid bivalves this reproduction strategy is rather unusual.…”

Male offspring production by asexual Potamopyrgus antipodarum, a New Zealand snail

“…Observed population densities in populations of P. antipodarum range from several hundred through many thousands of individuals per square meter of suitable surface (Dorgelo, 1987;Schreiber et al, 1998). Although we cannot directly extrapolate these densities to actual census population sizes, they indicate that P. antipodarum populations number at least in the hundreds, and may approach or surpass one million.…”