The Global Decline of Nonmarine Mollusks

Abstract Invertebrate species represent more than 99% of animal diversity; however, they receive much less publicity and attract disproportionately minor research effort relative to vertebrates. Nonmarine mollusks (i.e., terrestrial and freshwater) are one of the most diverse and imperiled groups of animals, although not many people other than a few specialists who study the group seem to be aware of their plight. Nonmarine mollusks include a number of phylogenetically disparate lineages and species-rich assemblages that represent two molluscan classes, Bivalvia (clams and mussels) and Gastropoda (snails, slugs, and limpets). In this article we provide an overview of global nonmarine molluscan biodiversity and conservation status, including several case studies documenting the diversity and global decline of nonmarine mollusks. We conclude with a discussion of the roles that mollusks and malacologists should play in conservation, including research, conservation management strategies, and education and outreach.

[1]  C. Lydeard,et al.  A Diverse and Endangered Aquatic Ecosystem of the Southeast United States , 1995 .

[2]  R. May,et al.  Taxonomic Bias in Conservation Research , 2002, Science.

[3]  David J. Rapport,et al.  What is ecosystem health , 1997 .

[4]  Brian D. Richter,et al.  Threats to Imperiled Freshwater Fauna , 1997 .

[5]  D. White,et al.  Rare Species and the Use of Indicator Groups for Conservation Planning , 2003 .

[6]  J. Garner,et al.  A molecular phylogeny of Mobile River drainage basin pleurocerid snails (Caenogastropoda: Cerithioidea). , 1997, Molecular phylogenetics and evolution.

[7]  G. Vermeij,et al.  Molecular Systematics and Phylogeography of Mollusks , 2003 .

[8]  P. Bouchet,et al.  Assessing the magnitude of species richness in tropical marine environments: exceptionally high numbers of molluscs at a New Caledonia site , 2002 .

[9]  R. Cowie.  Can snails ever be effective and safe biocontrol agents? , 2001 .

[10]  R. Cowie,et al.  The decline of native Pacific island faunas: changes in status of the land snails of Samoa through the 20th century , 2003 .

[11]  M. Haase,et al.  Radiation of crenobiontic gastropods on an ancient continental island: the Hemistomia-clade in New Caledonia (Gastropoda: Hydrobiidae) , 1998, Hydrobiologia.

[12]  S. Walsh,et al.  Status and restoration of the Etowah River, an imperiled Southern Appalachian Ecosystem , 1997 .

[13]  Michael S. Johnson,et al.  The extinction of Partula on Moorea. , 1988 .

[14]  B. Richter,et al.  Biodiversity Conservation at Multiple Scales: Functional Sites, Landscapes, and Networks , 2000 .

[15]  R. Hershler.  A systematic review of the hydrobiid snails (Gastropoda: Rissooidea) of the Great Basin, western United States. Part 1. Genus Pyrgulopsis , 1998 .

[16]  G. Ruiz,et al.  Pathways of introduction of nonindigenous land and freshwater snails and slugs. , 2003 .

[17]  G. Barker.  Naturalised terrestrial Stylommatophora (Mollusca: Gastropoda) , 1999 .

[18]  N. Stork.  Estimating the number of species on Earth , 1999 .

[19]  N. Poff,et al.  A Special Section on Dam Removal and River Restoration , 2002 .

[20]  Fred Wells,et al.  Marine Biodiversity Hotspots and Conservation Priorities for Tropical Reefs , 2002, Science.

[21]  M. Hadfield.  Extinction in Hawaiian achatinelline snails , 1986 .

[22]  M. Nowak,et al.  Habitat destruction and the extinction debt , 1994, Nature.

[23]  M. Freeman,et al.  Regional Effects of Hydrologic Alterations on Riverine Macrobiota in the New World: Tropical–Temperate Comparisons , 2000 .

[24]  T. Pearce,et al.  High diversity and regional endemism in land snails of eastern Tanzania , 1997, Biodiversity & Conservation.

[25]  S. Ferrier,et al.  Biogeographical concordance and efficiency of taxon indicators for establishing conservation priority in a tropical rainforest biota , 2001, Proceedings of the Royal Society of London. Series B: Biological Sciences.

[26]  R. P. Cook,et al.  Extinction or survival: partulid tree snails in American Samoa , 2001, Biodiversity & Conservation.

[27]  R. Cowie.  Invertebrate Invasions on Pacific Islands and the Replacement of Unique Native Faunas: A Synthesis of the Land and Freshwater Snails*Contribution no. 2001-001 of Bishop Museum's Pacific Biological Survey. , 2001, Biological Invasions.

[28]  Jonathan S. Adams,et al.  Precious heritage : the status of biodiversity in the United States , 2000 .

[29]  A. Solem.  New Caledonian land and fresh-water snails; an annotated check list. , 1961 .

[30]  W. Ponder,et al.  From Mound Springs to Mighty Rivers: The conservation Status of Freshwater Molluscs in Australia , 2003 .

[31]  A. Kohn,et al.  Endodontoid Land Snails from Pacific Islands (Mollusca: Pulmonata: Sigmurethra). Part II. Families Punctidae and Charopidae, Zoogeography. , 1983 .

[32]  S. Bauman.  Diversity and Decline of Land Snails on Rota, Mariana Islands , 1996 .

[33]  W. Ponder.  Conservation status, threats and habitat requirements of Australian terrestrial and freshwater molluscs , 1997 .

[34]  R. Bieler,et al.  Marine bivalves of the Florida Keys: discovered biodiversity , 2000, Geological Society, London, Special Publications.

[35]  From 61 species to five: endemic tree snails of the Society Islands fall prey to an ill-judged biological control programme , 2003, Oryx.

[36]  M. Norman.  Biodiversity Hotspots Revisited , 2003 .

[37]  R. Cowie,et al.  The Land Snails of a Small Tropical Pacific Island, Aunu'u, American Samoa , 2002 .

[38]  A. Solem,et al.  Endodontoid land snails from Pacific Islands (Mollusca : Pulmonata : Sigmurethra). , 1976 .

[39]  W. Ponder,et al.  The Other 99%: The Conservation and Biodiversity of Invertebrates , 1999 .

[40]  J. Rodman,et al.  The taxonomic impediment overcome: NSF's Partnerships for Enhancing Expertise in Taxonomy (PEET) as a model. , 2003, Systematic biology.

[41]  Barry D. Smith,et al.  Status of Tree Snails (Gastropoda: Partulidae) on Guam, with a Resurvey of Sites Studied by H. E. Campton in 1920 , 1992 .

[42]  B. Richardson,et al.  Spatial analysis of genetic variation as a rapid assessment tool in the conservation management of narrow-range endemics , 2002 .

[43]  J. Bay-Petersen.  The use of natural enemies to control agricultural pests. , 1990 .

[44]  Kevin J. Gaston,et al.  Taxonomy of taxonomists , 1992, Nature.

[45]  C. Nilsson,et al.  Fragmentation and Flow Regulation of River Systems in the Northern Third of the World , 1994, Science.

[46]  S. Tillier,et al.  PSEUDO-OPERCULATE PULMONATE LAND SNAILS FROM NEW CALEDONIA , 1984 .

[47]  W. Ponder.  Mound Springs of the Great Artesian Basin , 1986 .

[48]  Pierre Horwitz,et al.  Biodiversity, Endemism, Sense of Place, and Public Health: Inter‐relationships for Australian Inland Aquatic Systems , 2001 .

[49]  W. Ponder,et al.  Evaluation of Museum Collection Data for Use in Biodiversity Assessment , 2001 .

[50]  R. Cowie.  Decline and homogenization of Pacific faunas: the land snails of American Samoa ? ? Contribution num , 2001 .

[51]  R. C. Preece.  Impact of early Polynesian occupation on the land snail fauna of Henderson Island, Pitcairn group (South Pacific) , 1998 .

[52]  M. Hadfield,et al.  The Decimation of Endemic Hawai'ian Tree Snails by Alien Predators , 1993 .

[53]  R. Cowie,et al.  Growth and reproduction in Hawaiian succineid land snails , 2003 .

[54]  A. Guiller,et al.  Extreme divergence of mitochondrial DNA within species of pulmonate land snails , 1996, Proceedings of the Royal Society of London. Series B: Biological Sciences.

[55]  N. Myers.  LIFE FROM THEN UNTIL NOW , 2003 .