Biological Invasions

, Volume 10, Issue 5, pp 641–648 | Cite as

Eurasian otter (Lutra lutra) diet and prey selection in Mediterranean streams invaded by centrarchid fishes

  • Francisco Blanco-Garrido
  • José PrendaEmail author
  • Marta Narvaez
Original Paper


The diet of the Iberian otter (Lutra lutra) was determined by analysing 547 spraints collected at 28 sites within a wide area invaded by centrarchid fishes (pumpkinseed sunfish, Lepomis gibbosus and largemouth bass, Micropterus salmoides): the middle Guadiana basin (South-west Iberian Peninsula). Fish was the otters’ main prey, representing more than 60% of total individuals and more than 80% of total biomass. Otters preyed on most of the fish species captured in the field; however, the consumption of centrarchids was low compared to their abundance in the streams, and Jacobs’ index of preference showed a clear rejection of both species by the otter. Consumption of native fish genera (Squalius, Barbus and Chondrostoma) by otters increased in relation to their increase in the environment. In contrast, increasing numbers of L. gibbosus in the field was not reflected in otter consumption. The general decline of native freshwater fishes in Iberian rivers, the preferred prey of otters, together with the spread of exotic fish species (centrarchids and others) could put otter populations at risk.


Otter Iberian freshwater fishes Predation Invasive species Mediterranean streams Guadiana basin Biological conservation 



We greatly acknowledge Miguel Clavero, Antonia Rebollo and Jerónimo Valle for field and lab assistance. Professor Peter B. Moyle provided very useful comments and suggestions on the edition of the manuscript. Dr. Drake and two anonymous referees made very valuable suggestions to early versions of the manuscript. This study was financially supported by the SECEM (Sociedad Española para la Conservación y Estudio de los Mamíferos) and the Spanish Government projects REN2002-03513/HID (Ministerio de Ciencia y Tecnología) and CGL2005-02699/HID (Ministerio de Educación y Ciencia).


  1. Adrián MI, Delibes M (1987) Food habits of the otter (Lutra lutra) in two habitats of the Doñana National Park, SW Spain. J Zool Lond 212:399–406CrossRefGoogle Scholar
  2. Almaça C (1965) Contribution à la connaisance des poissons d’eaux interieures du Portugal. Arquiv Mus. Bocage 1:9–39Google Scholar
  3. Almaça C (1995) Fish species and varieties introduced into Portuguese inland waters. Lisboa: Publ. Avuls Mus. BocageGoogle Scholar
  4. Aparicio E, Vargas MJ, Olmo JM, de Sostoa A (2000) Decline of native freshwater fishes in a Mediterranean watershed on the Iberian Peninsula: a quantitative assessment. Environ Biol Fishes 59:11–19CrossRefGoogle Scholar
  5. Beja PR (1996) An analysis of otter Lutra lutra predation on introduced American crayfish Procambarus clarkii in Iberian streams. J Appl Ecol 33:1156–1170CrossRefGoogle Scholar
  6. Beja PR (1997) Predation by marine-feeding otters (Lutra lutra) in South-west Portugal in relation to fluctuating food resources. J Zool Lond 242:503–518CrossRefGoogle Scholar
  7. Bernardo JM, Ilhéu M, Matono P, Costa AM (2003) Interannual variation of fish assemblage structure in a Mediterranean river: implications of stream flow on the dominance of native or exotic species. Riv Res Appl 19:521–532CrossRefGoogle Scholar
  8. Blanco-Garrido F (2006) Ecología, distribución y conservación de peces continentales en el cuadrante suroccidental ibérico. Ph D Thesis. Universidad de HuelvaGoogle Scholar
  9. Clavero M, Garcia-Berthou E (2006) Homogenization dynamics and introduction routes of invasive freshwater fish in the Iberian Peninsula. Ecol Appl 16:2313–2324PubMedCrossRefGoogle Scholar
  10. Clavero M, Blanco-Garrido F, Prenda J (2004) Fish fauna in Iberian Mediterranean river basins: biodiversity, introduced species and damming impacts. Aquat Conserv Mar Freshw Ecosyst 14:575–585CrossRefGoogle Scholar
  11. Clavero M, Prenda J, Delibes M (2003) Trophic diversity of the otter (Lutra lutra L) in temperate and Mediterranean freshwater habitats. J Biog 30:761–769CrossRefGoogle Scholar
  12. Collares-Pereira MJ, Cowx IG, Ribeiro F, Rodrigues JA, Rogado L (2000) Threats imposed by water resource development schemes on the conservation of endangered fish species in the Guadiana river Basin in Portugal. Fish Manag Ecol 7:167–178CrossRefGoogle Scholar
  13. Correia AM (2001) Seasonal and interspecific evaluation of predation by mammals and birds on the introduced red swamp crayfish Procambarus clarkii (Crustacea, Cambaridae) in a freshwater marsh (Portugal). J Zool Lond 255:533–541CrossRefGoogle Scholar
  14. Delibes M, Adrián MI (1987) Effects of crayfish introduction on otter Lutra lutra food in the Doñana National Park, SW Spain. Biol Conserv 42:153–159CrossRefGoogle Scholar
  15. Doadrio I (ed) (2002) Atlas y libro rojo de los peces continentales de España. Dirección General de Conservación de la Naturaleza. 2nd ednGoogle Scholar
  16. Eklöv P, Hamrin SF (1989) Predatory efficiency and prey selection: interactions between pike Esox lucius, perch Perca fluviatilis and rudd Scardinius erythrophthalmus. Oikos 56:149–156CrossRefGoogle Scholar
  17. Erlinge S (1968) Food studies on captive otters (Lutra lutra L.). Oikos 19:259–270CrossRefGoogle Scholar
  18. Filipe AF, Cowx IG, Collares-Pereira MJ (2002) Spatial modelling of freshwater fish in semi-arid river systems: a tool for conservation. River Res Appl 18:123–136CrossRefGoogle Scholar
  19. Godinho FN, Ferreira MT (2000) Composition of endemic fish assemblages in relation to exotic species and river regulation in a temperate stream. Biol Invasions 2:231–244CrossRefGoogle Scholar
  20. Hasburgo-Lorena AS (1983) The status of the Procambarus clarkii population in Spain. Freshw Crayfish 6:131–133Google Scholar
  21. Heggberget TM, Moised KE (1994) Prey selection in coastal Eurasian otters Lutra lutra. Ecography 17:331–338CrossRefGoogle Scholar
  22. Holling CS (1959) Some characteristics of simple types of predation and parasitism. Can Entomol 91:385–398CrossRefGoogle Scholar
  23. Jacobs J (1974) Quantitative measurement of food selection. A modification of the forage ratio and Ivlevs electivity index. Oecologia 14:413–417CrossRefGoogle Scholar
  24. Jacobsen L (2005) Otter (Lutra lutra) predation on stocked brown trout (Salmo trutta) in two Danish lowland rivers. Ecol Fresh Fish 14:59–68CrossRefGoogle Scholar
  25. Kruuk H, Goudswaard PC (1990) Effects of changes in fish populations in Lake Victoria on the food of otters (Lutra maculicollis Schinz and Aonyx capensis Lichtenstein). African J Ecol 28:322–329CrossRefGoogle Scholar
  26. Lanski J, Molnar T (2003) Diet of otters living in three different habitats in Hungary. Folia Zool 52:378–388Google Scholar
  27. de López F, de la Cruz C (1985) Lepomis gibbous L. (Perciformes, Centrarchidae) nueva especie en la ictiofauna del Guadiana. Doñana Acta Vertebrata 12(1):165–166Google Scholar
  28. López-Nieves P, Casal H (1984) Food habits of the otter in central Sierra Morena (Córdoba, Spain). Acta Theriol 29:383–401Google Scholar
  29. Mason CF and Macdonald SM (1986) Otters: ecology and conservation. Cambridge University PressGoogle Scholar
  30. Morales JJ, Lizana M, Acera F (2004) Ecología trófica de la nutria paleártica (Lutra lutra) en el río Francia (cuenca del Tajo, Salamanca). Galemys 16:57–77Google Scholar
  31. Pedroso NM, Santos-Reis M (2006) Summer diet of Eurasian otters in large dams of south Portugal. Hystrix 17:117–128Google Scholar
  32. Peris SJ, Briz FJ, Campos F (1995) Shifts in the diet of the grey heron (Ardea cinerea) in the Duero basin, central-west Spain, following the introduction of exotic fish species. Folia Zool 44:97–102Google Scholar
  33. Prenda J, Granado-Lorencio C (1996) The relative influence of riparian habitat structure and fish availability on otter Lutra lutra L. sprainting activity in a small Mediterranean catchment. Biol Conserv 76:9–15CrossRefGoogle Scholar
  34. Prenda J, Arenas MP, Freitas D, Santos-Reis M, Collares-Pereira MJ (2002) Bone length of Iberian freshwater fish, as predictor of length and biomass of prey consumed by piscivorous. Limnética 21:15–24Google Scholar
  35. Revilla E, Palomares F (2002) Does local feeding specialization exist in Eurasian badgers? Can J Zool 80:83–93CrossRefGoogle Scholar
  36. Revilla E, Palomares F, Delibes M (2000) Defining key habitats for low density populations of Eurasian badgers in Mediterranean environments. Biol Conserv 95:269–277CrossRefGoogle Scholar
  37. Roselló E (1986) Atlas osteológico de los teleósteos ibéricos. I. Mandíbula inferior (dentario y articular). Tesis de Licenciatura. UAM, MadridGoogle Scholar
  38. Ruiz-Olmo J and Delibes M (1998) La nutria en España ante el horizonte del año 2000. SECEMGoogle Scholar
  39. Ruiz-Olmo J, López-Martín JM, Palazón S (2001) The influence of fish abundance on the otter (Lutra lutra) populations in Iberian Mediterranean habitats. J Zool Lond 254:325–336CrossRefGoogle Scholar
  40. Sheldon WG, Toll WG (1964) Feeding habits of the river otter in a reservoir in central Massachusetts. J Mammal 45:449–455CrossRefGoogle Scholar
  41. Taastrøm HM, Jacobsen L (1999) The diet of otters (Lutra lutra L.) in Danish freshwater habitats: comparisons of prey fish populations. J Zool Lond 248:1–13Google Scholar
  42. Webb JB (1980) Otter spraint analysis. Occasional Publication, Mammal Society, LondonGoogle Scholar

Copyright information

© Springer Science+Business Media B.V. 2007

Authors and Affiliations

  • Francisco Blanco-Garrido
    • 1
  • José Prenda
    • 1
    Email author
  • Marta Narvaez
    • 2
  1. 1.Departamento de Biología Ambiental y Salud PúblicaUniversidad de HuelvaHuelvaSpain
  2. 2.Departamento de Biología AplicadaEstación Biológica de Doñana (CSIC)SevillaSpain

Personalised recommendations