Marine Biology

, Volume 150, Issue 1, pp 149–160 | Cite as

Abundance of small cetaceans in waters of the central Spanish Mediterranean

  • Amaia Gómez de SeguraEmail author
  • E. A. Crespo
  • S. N. Pedraza
  • P. S. Hammond
  • J. A. Raga
Research Article


Seasonal aerial surveys were conducted in the waters of the central Spanish Mediterranean from 2001 to 2003 using the line transect sampling methodology to estimate cetacean abundance. The density of the three most abundant species, striped dolphin (Stenella coeruleoalba), bottlenose dolphin (Tursiops truncatus) and Risso’s dolphins (Grampus griseus), was estimated. In the case of the first two species, the density was estimated accounting for the proportion of submerged animals, while for Risso’s dolphin only the surface density could be estimated. The striped dolphin was the most abundant species in the study area with a mean density of 0.489 dolphins km−2(95% CI = 0.339–0.705) and a mean abundance of 15,778 dolphins (95% CI = 10,940–22,756). This density is comparable to that obtained in the International Ligurian Sea Cetacean Sanctuary. Striped dolphins were observed throughout the whole year and no seasonal changes in the density were detected. The mean density of bottlenose dolphins was an order of magnitude lower than that of striped dolphins (0.041 dolphins km−2; 95% CI = 0.023–0.075) with a mean abundance of 1,333 dolphins (95% CI = 739–2,407). The Risso’s dolphin had a surface estimated density of 0.015 dolphins km−2 (95% CI = 0.005–0.046) and a mean abundance of 493 dolphins (95% CI = 162–1,498). These results provide valuable biological information useful to develop conservation plans and establish a baseline for future population trend studies.


Bottlenose Dolphin Detection Function Aerial Survey School Size Small School 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



This study was carried out thanks to the financial support of the Spanish Ministry of Environment. The support of the Conselleria de Territorio y Vivienda of the Generalitat Valenciana particularly of J. Jimenez and the ALNITAK ONG especially of A. Cañadas and J. A. Vazquez is greatly appreciated. Thanks are due to all the observers who assisted in data collection: J. Martínez, P. Gonzalez, J. Barona, K. Lehnert and D. Perdiguero. The help of Dr. G. Donovan in methodological questions is also appreciated. Special thanks are due to J. Tomás and C. Agustí for their valuable contribution and support in this study.


  1. Aguilar A (2000) Population biology, conservation threats and status of Mediterranean striped dolphins (Stenella cerueloalba). J Cetacean Res Manage 2:17–26Google Scholar
  2. Aguilar A, Borrell A (1994) Abnormally high polychlorinated biphenyl levels in striped dolphin (Stenella coeruleoalba) affected by the 1990–1992 Mediterranean epizootic. Sci Total Environ 154:237–247CrossRefGoogle Scholar
  3. Barlow J (1995) The abundance of cetaceans in California waters. Part I: Ship surveys in summer and fall of 1991. Fish Bull 93:1–14Google Scholar
  4. Barlow J (1999) Trackline detection probability for long-diving whales. In: Garner GW, Amstrup SC, Laake JL, Manly BFJ, McDonald LL, Robertson DG (eds) Marine mammal survey and assessment methods. Balkema Press, Rotterdam, pp 209–221Google Scholar
  5. Barlow J, Oliver W, Jackson TD, Taylor BL (1988) Harbor porpoise, Phocoena phocoena, abundance estimation for California, Oregon, and Washington: aerial surveys. Fish Bull 86:433–444Google Scholar
  6. Bearzi G, Reeves RR, Notarbartolo di Sciara G, Politi E, Cañadas A, Frantzis A, Mussi B (2003) Ecology, status and conservation of short-beaked common dolphin Delphinus delphis in the Mediterranean Sea. Mammal Rev 33:224–252CrossRefGoogle Scholar
  7. Blanco C, Aznar J, Raga JA (1995) Cephalopods in the diet of the striped dolphin Stenella coeruleoalba from the western Mediterranean during an epizootic in 1990. J Zool Lond 237:151–158CrossRefGoogle Scholar
  8. Buckland ST, Anderson DR, Burnham KP, Laake JL, Borchers DL, Thomas L (2001) Introduction to distance sampling: estimating abundance of biological populations. Oxford University Press, OxfordGoogle Scholar
  9. Buckland ST, Anderson DR, Burnham KP, Laake JL, Borchers DL, Thomas L (2004) Advanced distance sampling: estimating abundance of biological populations. Oxford University Press, OxfordGoogle Scholar
  10. Cañadas A, Hammond PS (2006) Model-based abundance estimates for bottlenose dolphin (Tursiops truncatus) off southern Spain. J Cetacean Res Manage (in press)Google Scholar
  11. Cañadas A, Sagarminaga R, Garcia-Tiscar S (2002) Cetacean distribution related with depth and slope in the Mediterranean waters off southern Spain. Deep Sea Res I 49(11):2053–2073CrossRefGoogle Scholar
  12. Carretta JV, Forney KA, Laake JL (1998) Abundance of South California coastal bottlenose dolphins estimated from tandem aerial surveys. Mar Mamm Sci 14:655–675CrossRefGoogle Scholar
  13. Dolar MLL (1999) Abundance, distribution and feeding ecology of small cetaceans in the eastern Sulu Sea and Tanon Strait, Philippines. PhD Dissertation, University of California, San DiegoGoogle Scholar
  14. Forcada J, Hammond PS (1998) Geographical variation in abundance of striped and common dolphins of the western Mediterranean. J Sea Res 39:313–325CrossRefGoogle Scholar
  15. Forcada J, Aguilar A, Hammond PS, Pastor X, Aguilar R (1994) Distribution and number of striped dolphins in the western Mediterranean Sea after the 1990 epizootic outbreak. Mar Mamm Sci 10:137–150CrossRefGoogle Scholar
  16. Forcada J, Notarbartolo di Sciara G, Fabbri F (1995) Abundance of fin whales and striped dolphins summering in the Corso-Ligurian basin. Mammalia 59:127–140CrossRefGoogle Scholar
  17. Forcada J, Gazo M, Aguilar A, Gonzalvo J, Fernandez-Contreras M (2004) Bottlenose dolphin abundance in the NW Mediterranean: addressing heterogeneity in distribution. Mar Ecol Prog Ser 275:275–287CrossRefGoogle Scholar
  18. Forney KA, Barlow J (1998) Seasonal patterns in the abundance and distribution of California cetaceans, 1991–1992. Mar Mamm Sci 14:460–489CrossRefGoogle Scholar
  19. Forney KA, Barlow J, Carretta JV (1995) The abundance of cetaceans in California waters. Part II: Aerial surveys in winter and spring of 1991 and 1992. Fish Bull 93:15–26Google Scholar
  20. Gannier A (1997) Estimation de l’abondance estivale du rorqual commun Balaenoptera physalus (Linné, 1758) dans le basin liguro-provençal (Méditerranée Occidentale). Rev Ecol 52:69–85Google Scholar
  21. Gannier A (1998a) Une estimation de l’abondance estivale du dauphin bleu et blanc Stenella coeruleoalba (Meyen, 1833) dans le future sanctuaire marin international de Méditerranée Nord-occidentale. Rev Ecol 53:255–271Google Scholar
  22. Gannier A (1998b) Variation saisonnière de l’affinité bathymétrique des cétacés dans le basin liguro-provençal (Méditerranée Occidentale). Vie Milieu 48:25–34Google Scholar
  23. Gannier A, Gannier O (1997) New results on the seasonal variation of the cetacean population in the liguro-provençal basin. Eur Res Cetaceans 11:91–94Google Scholar
  24. Gómez de Segura A, Hammond PS, Raga JA (2006) Influence of environmental factors on small cetacean distribution in the Spanish Mediterranean and its conservational applications. J Zool (in review)Google Scholar
  25. Guerra A (1992) Mollusca, Cephalopoda. In: Ramos MA (ed) Fauna Ibérica, vol 1. Museo Nacional de Ciencias Naturales, CSIC, Madrid, p 327Google Scholar
  26. Hoyt E (2005) Marine protected areas for whales, dolphins and porpoises: a world handbook for cetacean habitat conservation. Earthscan, LondonGoogle Scholar
  27. Laake JL, Calambokidis J, Osmek SD, Rugh DJ (1997) Probability of detecting harbour porpoise from aerial surveys: estimating g(0). J Wildl Manage 61:63–75CrossRefGoogle Scholar
  28. Meotti C, Podestà M (1997) Stomach contents of striped dolphin, Stenella coeruleoalba (Meyen, 1833), from the Western Ligurian Sea (Cetacea, Delphinidae). Atti Soc It Sci Nat Museo Civ Stor Nat Milano 137(I-II):5–15Google Scholar
  29. Mullin KD, Fulling GL (2003) Abundance of cetaceans in the southern U.S. North Atlantic Ocean during summer 1998. Fish Bull 101:603–613Google Scholar
  30. Notarbartolo di Sciara G (ed) (2002) Cetaceans of the Mediterranean and Black Seas: state of knowledge and conservation strategies. Report to the ACCOBAMS Secretariat, MonacoGoogle Scholar
  31. Notarbartolo di Sciara G, Zanardelli M, Jahoda M, Panigada S, Airoldi S (2003) The fin whale Balaenoptera physalus (L. 1758) in the Mediterranean Sea. Mammal Rev 33:105–150CrossRefGoogle Scholar
  32. Perrin WF, Wilson CE, Archer FI (1994) Striped dolphin—Stenella coeruleoalba (Meyen. 1833). In: Ridgway SH, Harrison SR (eds) Handbook of marine mammals. The first book of dolphins, vol 5. Academic Press, London, pp 129–160Google Scholar
  33. Raga JA, Pantoja J (eds) (2005) Proyecto Mediterráneo: Zonas de especial interés para la conservación de los cetáceos en el Mediterráneo español. Publicaciones del Ministerio de Medio Ambiente, MadridGoogle Scholar
  34. Reeves RR, Smith B, Crespo EA, Notarbartolo di Sciara G (eds) (2003) Dolphins, whales and porpoises: 2002–2010 conservation action plans for the world’s cetaceans. IUCN/SSC Cetacean Specialist Group. IUCN, Gland, Switzerland and Cambridge, UKGoogle Scholar
  35. Rice WR (1989) Analysing tables of statistical test. Evolution 43:223–225CrossRefGoogle Scholar
  36. Seber GAF (1982) The estimation of animal abundance and related parameters. Macmillan, New YorkGoogle Scholar
  37. Sheskin DJ (2000) Handbook of parametric and nonparametric statistical procedures, 2nd edn. Chapman & Hall/CRC Press, New YorkGoogle Scholar
  38. Silvani L, Gazo M, Aguilar A (1999) Spanish driftnet fishing and incidental caches in the western Mediterranean. Biol Conserv 90:79–85CrossRefGoogle Scholar
  39. Slooten E, Dawson SM, Rayment WJ (2004) Aerial surveys for coastal dolphins: abundance of Hector’s dolphins off the South Island West Coast, New Zealand. Mar Mamm Sci 20:477–490CrossRefGoogle Scholar
  40. Tudela S, Kai Kai A, Maynou F, El Andalossi M, Guglielmi P (2005) Driftnet fishing and biodiversity conservation: the case study of the large-scale Moroccan driftnet fleet operating in the Alboran Sea (SW Mediterranean). Biol Conserv 121:65–78CrossRefGoogle Scholar
  41. Thomas L, Laake JL, Strindberg S, Marques FFC, Buckland ST, Borchers DL, Anderson DR, Burnham KP, Hedley SL, Pollard JH, Bishop JRB (2004) Distance 4.1. Release 2. Research Unit for Wildlife Population Assessment, University of St. Andrews, UK.
  42. Valeiras J, Camiñas JA (2002) Captura accidental de mamíferos marinos en las pesquerías españolas de palangre de pez espada y túnidos en el Mediterráneo. In: Alonso JM, Lopez A (eds) Libro de resúmenes del II Simposium de la Sociedad Española de Cetáceos, Madrid, pp 30–33Google Scholar
  43. Wade PR, DeMaster DP (1999) Determining the optimum interval for abundance surveys. In: Garner GW, Amstrup SC, Laake JL, Manly BFJ, McDonald LL, Robertson DG (eds) Marine mammal survey and assessment methods. Balkema Press, Rotterdam, pp 53–66Google Scholar
  44. Wade PR, Gerrodette T (1993). Estimates of cetacean abundance and distribution in the eastern tropical Pacific. Rep Int Whal Comm 43:477–494Google Scholar
  45. Würtz M, Marrale D (1993) Food of striped dolphin, Stenella coeruleoalba, in the Ligurian Sea. J Mar Biol Assoc 73:571–578CrossRefGoogle Scholar

Copyright information

© Springer-Verlag 2006

Authors and Affiliations

  • Amaia Gómez de Segura
    • 1
    Email author
  • E. A. Crespo
    • 2
  • S. N. Pedraza
    • 2
  • P. S. Hammond
    • 3
  • J. A. Raga
    • 1
  1. 1.Departmento de Zoología Marina, Instituto Cavanilles de Biodiversidad y Biología EvolutivaUniversidad de ValenciaValenciaSpain
  2. 2.Centro Nacional Patagónico (CONICET) and Universidad Nacional de la PatagoniaPuerto MadrynArgentina
  3. 3.Sea Mammal Research Unit, Gatty Marine LaboratoryUniversity of St AndrewsSt AndrewsUK

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