Potamotrygon Leopoldi, Xingu River Ray
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The IUCN Red List of Threatened Species™ ISSN 2307-8235 (online) IUCN 2008: T39403A10226180 Potamotrygon leopoldi, Xingu River Ray Assessment by: Charvet-Almeida, P., Rosa, R.S. & Pinto de Almeida, M. View on www.iucnredlist.org Citation: Charvet-Almeida, P., Rosa, R.S. & Pinto de Almeida, M. 2009. Potamotrygon leopoldi. The IUCN Red List of Threatened Species 2009: e.T39403A10226180. http://dx.doi.org/10.2305/IUCN.UK.2009-2.RLTS.T39403A10226180.en Copyright: © 2015 International Union for Conservation of Nature and Natural Resources Reproduction of this publication for educational or other non-commercial purposes is authorized without prior written permission from the copyright holder provided the source is fully acknowledged. Reproduction of this publication for resale, reposting or other commercial purposes is prohibited without prior written permission from the copyright holder. For further details see Terms of Use. The IUCN Red List of Threatened Species™ is produced and managed by the IUCN Global Species Programme, the IUCN Species Survival Commission (SSC) and The IUCN Red List Partnership. The IUCN Red List Partners are: BirdLife International; Botanic Gardens Conservation International; Conservation International; Microsoft; NatureServe; Royal Botanic Gardens, Kew; Sapienza University of Rome; Texas A&M University; Wildscreen; and Zoological Society of London. If you see any errors or have any questions or suggestions on what is shown in this document, please provide us with feedback so that we can correct or extend the information provided. THE IUCN RED LIST OF THREATENED SPECIES™ Taxonomy Kingdom Phylum Class Order Family Animalia Chordata Chondrichthyes Rajiformes Potamotrygonidae Taxon Name: Potamotrygon leopoldi Castex & Castello, 1970 Common Name(s): • English: Xingu River Ray Taxonomic Notes: This freshwater stingray presents a moderate chromatic variation. It could be mistaken for Potamotrygon henlei, which has very similar colour patterns (authors´ pers. obs.). Assessment Information Red List Category & Criteria: Data Deficient ver 3.1 Year Published: 2009 Date Assessed: June 24, 2003 Annotations: Needs Updating Justification: Potamotrygon leopoldi is an endemic freshwater stingray restricted to the Xingu River Basin in Brazil. It is seldom taken for food but juveniles enter the ornamental fish trade due to the attractive colour pattern and the species faces persecution in some areas due to fear of sting injuries. Its relatively limited distribution renders it vulnerable to habitat degradation. The lack of life history and population data for this species preclude an accurate assessment of its conservation status, although studies are currently underway and a revised assessment is recommended in the near future. Previously Published Red List Assessments 2000 – Data Deficient (DD) Geographic Range Range Description: South America inland waters: Northern Brazil. Possibly endemic to the Xingu River Basin (Brazil) (Rosa 1985). Incorrectly indicated as being restricted to a single river (Carvalho et al. 2003), this species has been observed and photographed in the Xingu River and at least two of its tributaries (Curuá and Iriri Rivers) (Charvet-Almeida and Almeida pers. obs.). Country Occurrence: Native: Brazil © The IUCN Red List of Threatened Species: Potamotrygon leopoldi – published in 2009. 1 http://dx.doi.org/10.2305/IUCN.UK.2009-2.RLTS.T39403A10226180.en Distribution Map © The IUCN Red List of Threatened Species: Potamotrygon leopoldi – published in 2009. 2 http://dx.doi.org/10.2305/IUCN.UK.2009-2.RLTS.T39403A10226180.en Population Population trends and dynamics have never been estimated for this species but are currently under study. Current Population Trend: Unknown Habitat and Ecology (see Appendix for additional information) This species seems to prefer rocky river bottoms where it probably more easily finds freshwater snails and crabs that are among its main food items (Charvet-Almeida and Almeida pers. obs.). The available unpublished data indicates that this species has a relatively high fecundity compared with other potamotrygonids, ranging from 4 to 12 pups per litter (average of 7-8) (Charvet-Almeida and Almeida unpublished data). Further information regarding habitat and ecology aspects of P. leopoldi are currently under study. Systems: Freshwater Threats (see Appendix for additional information) Despite occurring in a large river basin, this species has a relatively restricted range (limited to the Xingu River Basin), and serious impacts in this region may result in population declines. Habitat loss/degradation involving the development and expansion of agriculture, livestock, ongoing gold mining, fisheries and logging are a threat to this species. Water contaminants originating mainly from agricultural, domestic, sediment, sewage and solid wastes, as a consequence of this development, are also considered threats for P. leopoldi. Inadequate land management and deforestation, mainly in the Xingu River headwaters and some of its tributaries, are significantly increasing and could bring serious impacts to the entire basin. Geological characteristics of the Xingu River favour the building of dams throughout the basin and potentially represent a threat to this species; however, it is uncertain how P. leopoldi populations will be affected by this impact. Genetic isolation is likely to take place if the proposed dams of the Belo Monte Hydroelectric Complex are built in the near future. Human settlement, tourism and recreation often lead to persecution (killing freshwater stingrays due to fear of sting injuries). This species is seldom used as a food source but is captured as bycatch (mainly by hooking, netting, entanglement and occasionally by poisoning) in other target species fisheries. Juveniles are captured for the international ornamental fish trade and at present this activity is regulated by an export quota system that must be correctly enforced by the environmental and export related national agencies. It is important to note that captures for ornamental purposes represents an important socio-economic activity for riparian residents in this region. © The IUCN Red List of Threatened Species: Potamotrygon leopoldi – published in 2009. 3 http://dx.doi.org/10.2305/IUCN.UK.2009-2.RLTS.T39403A10226180.en Historically, severe droughts (associated with the El-Niño phenomenon) in some small tributaries of the Xingu river have caused high mortality (Charvet-Almeida, pers. obs.). Conservation Actions (see Appendix for additional information) Further management plans and legislation improvement are required conservation measures for P. leopoldi. Local residents and communities should be involved in the management of this species and it is essential to develop public awareness through education and capacity building programmes. Public awareness could also help reduce persecution (due to fear of injury) associated with tourism, recreation and human settlement. Sustainable yield limits for ornamental purposes must be monitored to ensure the survival of this species. Preliminary data (Charvet-Almeida unpublished data) indicate that illegal captures have reduced significantly after the establishment of an export quota system but further study is needed to ensure this is maintained. Adequate law enforcement is an essential conservation measure when it comes to the ornamental fish trade. Habitat maintenance and conservation are also fundamental aspects to be included in management plans and need to be enforced by existing and new legislation. Headwaters are certainly among a priority. Further studies about life history and population dynamics are already underway. Credits Assessor(s): Charvet-Almeida, P., Rosa, R.S. & Pinto de Almeida, M. Reviewer(s): Kyne, P.M., Cavanagh, R.D. & Fowler, S.L. (Shark Red List Authority) © The IUCN Red List of Threatened Species: Potamotrygon leopoldi – published in 2009. 4 http://dx.doi.org/10.2305/IUCN.UK.2009-2.RLTS.T39403A10226180.en Bibliography Carvalho, M.R. de, Lovejoy, N.R. and Rosa, R.S. 2003. Family Potamotrygonidae (river stingrays). In: R.E. Reis, S.O. Kullander and C.J. Ferraris Jr. (eds), Check List of the Freshwater Fishes of South and Central America, pp. 22-28. Porto Alegre, Edipucrs. Charvet-Almeida, P., Araújo, M.L.G., Rosa, R.S. and Rincon, G. 2002. Neotropical Freshwater Stingrays: diversity and conservation status. Shark News 14: 1-2. Compagno, L.J.V. 2005. Checklist of living Chondrichthyes. In: S.L. Fowler, M. Camhi, G.H. Burgess, G.M. Cailliet, S.V. Fordham, R.D. Cavanagh, C.A. Simpfendorfer and J.A. Musick (eds), Sharks, Rays and Chimaeras: The Status of the Chondrichthyan Fishes. Status Survey, pp. 461. IUCN SSC Shark Specialist Group, IUCN, Gland, Switzerland and Cambridge, UK. IUCN. 2009. IUCN Red List of Threatened Species (ver. 2009.2). Available at: www.iucnredlist.org. (Accessed: 3 November 2009). Rosa, R.S. 1985. A Systematic Revision of the South American Freshwater Stingrays (Chondrichthyes: Potamotrygonidae). School of Marine Science, College of William and Mary. Rosa, R.S. and Araújo, M.L.G. 2005. Potamotrygon leopoldi. In: S.L. Fowler, R.D. Cavanagh, M. Camhi, G.H. Burgess, G.M. Cailliet, S. V. Fordham, C.A. Simpfendorfer and J.A. Musick (eds), Sharks, Rays and Chimaeras: The Status of the Chondrichthyan Fishes. Status Survey, IUCN SSC Shark Specialist Group, IUCN, Gland, Switzerland and Cambridge, UK. Ross, R.A. and Schafer, F. 2000. Freshwater Rays. Mörfelden-Walldorf, Aqualog. Citation Charvet-Almeida, P., Rosa, R.S. & Pinto de Almeida,