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Reproduction:
Like the other local freshwater pulmonary snails (Basommatophora), the fountain bladder snail is dioecious. HOLTZFUSS (1914) was able to prove that the species is self-fertilizing by five generations of snails, each raised on their own in the laboratory.
According to HEITKAMP (1982; in: GLÖER 2002), their reproductive period in Lower Saxony in nature runs from May to autumn. GRABOW (2000) gives April to September for this time span. DUNCAN (1959) observed the main activity of English snails in nature in April and May. NEKRASSOW (1928) mainly found these activities in July until the first half of August in the Russian populations.
The very transparent, gelatinous egg clutches are attached to aquatic plants and other substrates. DUNCAN (1959) observed in the laboratory that the clutches are laid mostly at night, between midnight and 8 a.m. They are relatively high-convex, roundish when laid by younger snails, short and oval by older ones (GRABOW 2000). According to HAZAY (1881; in NEKRASSOW 1928), each of the about 10 mm long clutches contains 10 to 20 eggs, to NEKRASSOW about 10, more rarely 16 to 20, to MERMOD (1930; in: GLOER 2002) 5 to 22, respectively to GRABOW (2000) 10 to 20 eggs. The short, oval, nearly round eggs are, according to measurements by NEKRASSOW 0.92-0.97mm long and 0.7-0.78mm wide. Their inner membrane is impressed on one or both poles. The outer membrane has several layers, whereas the outer layers are slightly detatched from the inner membrane on the poles or are slightly thicker. The outermost membrane layer is often bent up and open at the edge.
Depending on the water temperature, the young snails gnaw through the clutches after two to four weeks after laying.
Life Cycle, Life Span:
According to examinations of different authors in Northern and Central Europe, a life cycle with one generation/a is most common, whereas the adult snails soon die after the reproductive period in spring (in: CAQUET 1993). According to HEITKAMP (1982; in: GLÖER 2002) the snails reach a maximum age of 11 to 14 months in southern Lower Saxony, to CAQUET (1993) 13 to 14 months near Paris/France.
However, a population in nature in Loch Lomond/Scotland was observed to bring forth two generations/a. The snails hatched in spring reproduced in summer and died consequently. This spring generation reaches thus only a maximum age of 3 to 4 months (RUSSEL-HUNTER 1961; in: GLÖER 2002).
Furtherly, populations were observed whose spring generation already reproduces in summer, hibernates and only dies after reproducing for the second time the next spring (DUNCAN 1959 & RUSSEL-HUNTER 1961; both cited in CAQUET 1993).
Food:
According to GRABOW (2000), the fountain bladder snail mostly feeds on dead plants and surface film in nature. RAEVELL (1980; in: GLÖER 2002) found 85% detritus, 10% diatoms and 5% green algae in their intestinal content.
Behavior:
The relatively high speed bladder snails in general crawl on the most different substrates at is typical. Furtherly they can often be observed hanging on the water surface, eating the biofilm, and they are able to move freely in the water, hanging from a cord of mucus.
They can also quite often be observed sitting several centimeters above the waterline. It is assumed that they do thus not only reach food unavailable to other water snails, but also actively get away from predators, as ALEXANDER & COVICH (1991) were able to prove for the bladder snail Physella virgata, among others.
When disturbed, bladder snails often move their shell back and forth in a strikingly jerky fashion. Diverse authors agree that this is primarily a defensive behavior. When these defensive movements are not sufficient (or spontaneously), the fountain bladder snail lets go of its substrate and floats up to the water surface (HEROLD 1974) or falls down to the ground. This behavior is also displayed towards conspecifics, however, to a lesser degree than towards snail leeches, whereby according to TOWNSEND & MCCARTHY (1980) the smaller population densities can be explained.
According to my own observance from short-time keeping in an aquarium the snails are always active and can be seen on various substrates, all tank decoration, on the water surface as well as on aquatic plants
Keeping and Socialization in the Aquarium:
In contrast to the well-known bladder snails of the genus Physella the editor does not have any reports about keeping Physa fontinalis in the aquarium. However, we may safely assume that the fountain bladder snail reacts more sensitive to high water temperatures and less than optimal water parameters. In any case, a gapless cover is recommendable in order to avoid losses of adventurous snails ready for shore.
Parasites, Commensals:
NEKRASSOW (1928) observed that the clutches are often infested by the predating rotifer Proales gigantea. From time to time also beetles of the genus Haliplidae lay their eggs into the clutches of the fountain bladder snail.
Besides other water snails, also the local bladder snails are infested by different species of trematods (liver flukes) as intermediary host. The proper final host of the cercaria (a larvae stage of the flukes) leaving the snails are water fowl in general, fish, amphibians or mammals. Most cercaria get into their final host by getting eaten together with the infested snail. There they bore through the intestinal wall and infest the inner organs.
In fountain bladder snails FUCHS (2002, s. Weblinks) et.al. found various trematode species, whose final hosts are brids or flukes in the area Westfalen-Lippe.
On Physidae (also Radix, Lymnaea, Planorbidae and species of further families) from nature, especially on the head region, up to 3 mm long white worms can be found, attached to the snail‘s body with their rear end and performing searching movements with their fore end. Often these are identified as the oligochaete Chaetogaster limnaei limnaei (BAER 1827), which sucks in unspecific tiny particles as food immediately in front of the snail as well as food rests. In contrast to the subspecies C. l. vaghini (GRUFFYDD 1965) living parasitically in water snails the aforementioned subspecies does not affect the snail‘s vitality nor its behavior (s. weblinks: WÄGELE et.al. as well as Wikipedia).
Endangerment:
Due to declining populations in many locations, the fountain bladder snail has been taken up into the nationwide Red List for Germany as vulnerable (1998) and in the Czech Republic it is assumed to be potentially endangered ("NT"). In Slovenia (2001) and Switzerland (1994) they have endangered species status, in Austria (1994) they are assumed to be critically endangered. On the International Red List (IUCN, as of 2008) as well as those of Norway (2006), Sweden (2001), Estonia (year?), Lithuania (2003), The Netherlands (2004) and Poland (2004) it is not listed.
Additional information:
No more species of the genus Physa or subspecies of the fountain bladder snail Physa fontinalis are listed in the collation section of FaunaEuropaea (s. weblinks).
Literature:
CAQUET, T. (1993): Comparative life-cycle, biomass and secondary production of three sympatric freshwater gastropod species. Journal of Molluscan Studies 59: 43-50.[Lebenszyklus und Produktivität von Lymnaea palustris, Physa fontinalis und Anisus rotundatus in einem Graben bei Paris/F]
GLÖER, P. (2002): Süßwassermollusken Nord und Mitteleuropas. Bestimmungsschlüssel, Lebensweise, Verbreitung. In: Die Tierwelt Deutschlands. Conchbooks, Hackenheim. ISBN 3-925919-60-0.
[Angaben zu Merkmalen, Verbreitung, Biologie, Ökologie usw.]
GLÖER, P & MEIER-BROOK, C. (2003): Süßwassermollusken. Ein Bestimmungsschlüssel für die Bundesrepublik Deutschland. Deutscher Jugendbund für Naturbeobachtung, Hamburg. ISBN 3-923376-02-2.
[kurze Artbeschreibung, Verbreitungskarte für Deutschland]
GRABOW, K. (2000): Farbatlas Süßwasserfauna – Wirbellose. Eugen Ulmer GmbH & Co., Stuttgart. ISBN 3-8001-3145-5.
[kurze Artbeschreibung u.a. auch mit Angaben Biologie und Ölologie]
NEKRASSOW, A.D. (1928): Vergleichende Morphologie der Laiche von Süßwassergastropoden. Z. f. Morphol. u. Ökol. d. Tiere, Bd. 18, pp. 1-35.
[Exakte Beschreibungen der Gelege verschiedener Arten aus dem Fluß Kljasma und Tümpeln bei Bolschewo/Rußland]
TOWNSEND, C.R. & MCCARTHY, T.K. (1980): On the defence strategy of Physa fontinalis (L.), a freshwater pulmonate snail. Oecologia 46: 15-79.[zum Verhalten des Abschüttelns von Schneckenegeln, aber auch Artgenossen]
WIESE, V: (1991): Atlas der Land- und Süßwassermollusken in Schleswig-Holstein. Landesamt für Naturschutz und Landschaftspflege, Kiel. ISBN 3-923339-40-2.
[Verbreitungskarte von Schleswig-Holstein, Zeichnung und kurze Angaben zu Vorkommen]
weblinks:
Aquarienschnecken-Forum.de: [Beschreibung eines gemeinsamen Habitates mit Theodoxus fluviatilis, Fotos]
Rote Listen Süßwassermollusken [Linksammlung]
ALEXANDER, J.E. & COVICH, A.P. (1991): Predation Risk and Avoidance Behavior in Two Freshwater Snails. Bid. Bull. 180: 387-393.
[Reaction to predators of Physella virgata and Planorbella trivolvis in the presence of Procambarus simulans]
Atlasproject Nederlandse Mollusken (ANM): Physa fontinalis (LINNAEUS, 1758) Bron-blaashoren.
[Range map of The Netherlands]
BERG, K. & OCKELMANN, K.W. (1959): The Respiration of Freshwater Snails. J. Exp. Biol. Vol. 36 No. 4 pp. 690-708.
[Examination of the oxygen needs of diverse freshwater snail species]
CARLSSON, R. (2006): Freshwater snail assemblages of semi-isolated brackish water bays on the Åland Islands, SW Finland. Boreal Environment Research ISSN 1239-6095, 11: 371-382.
CIOBOIU, O. (2003): Diversity of Gastropoda in the Romanian sector of the Danube lower hydrographic basin.
[Species locations in Romania on river area levels]
DALFREDDO, C. & MAIOLINI, B. (2004): Il popolamento malacologico di alcuni laghi trentini a confronto 70 anni dopo. Studi Trent. Sci. Nat., Acta Biol., 80 (2003): 175-177. ISSN 0392-0542
[First findings of P. fontinalis in Lake Caldonazzo/Trentin/Italien, among others]
Deutsche Malakozoologische Gesellschaft (Red.: WIESE, V., Stand: 07/2008): Molluscs of Central Europe – Nomenklaturliste.
[Systematics of European molluscs – with trivial names]
FUCHS, C. (2002): Cercarien aus Physa fontinalis. Webseite der Universität Bielefeld, Fakultät für Biologie, Parasitologie/Gewässerökologie, Arbeitsgruppe Mannesmann.
[Trematode fauna found in Physa fontinalis in the area Westfalen/Lippe]
Fauna Europaea
[European systematics, information about the range of Physa fontinalis
HEROLD, H. (1974): Zum Abwehrreflex bei Physa fontinalis (LINNAEUS) und Radix auricularia (LINNAEUS). Mitt. Zool. Ges. Braunau Bd. 2, Nr. 1/2, pp. 33-36.
[Overservations regarding the defensive reflex]
National Biodiversity Network: Grid map of records on the Gateway for Common Bladder Snail Physa fontinalis
[Data base range maps of the British Isles]
USTAOĞLU, M. R. & BALIK, S. & ÖZBEK, M. (2001): Işıklı Gölü (Çivril-Denizli)’nün Mollusca Faunası. - Ege University Press, Volume 18, Issue (1-2): 135-139. ISSN 1300 – 1590.
[Malakozoological examination, also with water parameters given, in Turkish]
WÄGELE, H. & SCHÄFER, F.W. & SCHÄFER, A. & STANJEK, G.H. (Stand: 08.06.2008): Bauchborstenwürmchen, Chaetogaster limnaei. Ein auf Schnecken lebender Gliederwurm.
[Website with a short portrait and microscopical photos of Chaetogaster limnaei]
: Family Physidae. A supplement to the workbook accompanying the FMCS Freshwater Identification Workshop, University of Alabama, Tuscaloosa.
[Overview over the genus Physidae, tutorial for genital preparation]
WETHINGTON, A.R. & LYDEARD, C. (2007): A Molecular Phylogeny of Physidae (Gastropoda: Basommatophora) based on Mitochondrial DNA Sequences. Journal of Molluscan Studies pp. 1 of 17. Published by Oxford University Press on behalf of The Malacological Society of London.
[molekulargenetical examination of Physidae ]
WIESE, V: (1991): Atlas der Land- und Süßwassermollusken in Schleswig-Holstein. Landesamt für Naturschutz und Landschaftspflege Schleswig-Holstein. ISBN 3-923339-40-2.
[Range map of Schleswig-Holstein, drawing and short information to the locations]
Wikipedia (Stand: 10.05.2008): Chaetogaster.
[Species with special focus on the life strategies of the subspecies of Chaetogaster limnaei]
YILDIRIM, M. Z. & GÜMÜŞ, B. A. & KEBAPÇI, Ü. & KOCA, S. B. (2006): The Basommatophoran Pulmonate Species (Mollusca: Gastropoda) of Turkey. Turk J Zool 30: 445-458.
[Information about the range of Pulmonata in Turkey]
ZETTLER, M. L. (2000): Bewertung des ökologischen Zustandes von Fließgewässern in Mecklenburg-Vorpommern über die Malakofauna als Indikatororganismen. Natur und Naturschutz in Mecklenburg-Vorpommern. 35: 3-36.
[Information about habitats and range of the species, on page 16]
ZETTLER, M. L., ZETTLER, A. & DAUNYS, D. (2005): Bemerkenswerte Süßwassermollusken aus Litauen. Aufsammlungen vom September 2004. Malak. Abh. 23: 27-40.
[Species locations for Lithuania]
This page was actualized on December 8, 2008
Author: schneckli
Translator: Ulrike Bauer
internationale Trivialnamen für die Suchmaschinen:
englisch: Common Bladder Snail
französisch: Physe des fontaines
holländisch: Bron-blaashoren
lettisch: burbuļu kreiļgliemezis
polnisch: rozdętka pospolita
schwedisch: Allmän blåssnäcka
slovakisch: fyza pririečna
tschechisch: levatka říční
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