Marine Biology

, 163:21 | Cite as

Sea turtle strandings along the Portuguese mainland coast: spatio-temporal occurrence and main threats

  • Lídia Nicolau
  • Marisa Ferreira
  • Jorge Santos
  • Hélder Araújo
  • Marina Sequeira
  • José Vingada
  • Catarina Eira
  • Ana Marçalo
Original paper


The present study is a detailed analysis of sea turtle strandings over a 36-year period (1978–2013) along the Portuguese mainland coast. Out of the 806 stranded individuals, the loggerhead turtle Caretta caretta was the most frequent species (57.1 %) followed by the leatherback turtle Dermochelys coriacea (41.8 %), while green turtles Chelonia mydas and Kemp’s Ridley turtles Lepidochelys kempii were rare (respectively 1.0 and 0.1 %). Relative stranding densities of loggerheads showed an increase through time, whereas two leatherback stranding peaks were detected during the years 1994–1998 and 2009–2013. The highest loggerhead stranding density was observed on the southern coast during spring and summer when they are more susceptible to anthropogenic threats. The highest number of leatherback strandings was observed in the North-Central and Central-South western sectors during autumn and in the southern sector during summer, which may relate to seasonal food availability and water temperature considering those stranded animals that were subject to a post-mortem evaluation interaction with fisheries as the primary cause of stranding. Results show for the first time that waters off the Portuguese mainland coast is an important pathway for loggerheads and leatherbacks in the North Atlantic region. The present study serves as important baseline to the development of future sea turtle conservation efforts in the Portuguese mainland coast.


Green Turtle Loggerhead Turtle Portuguese Coast Significant Seasonal Difference Leatherback Turtle 
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 work was partly funded by the Portuguese Wildlife Society and projects SafeSea EEA-Grants and European Commission’s Life Programme (MarPro NAT/PT/00038). This study was also partly supported by the Portuguese Foundation for Science and Technology (FCT) with grants SFRH/BD/51416/2011 to L. Nicolau, SFRH/BPD/64889/2009 to A. Marçalo and SFRH/BD/30240/2006 to M. Ferreira. C. Eira is supported by MARES (CENTRO-07-ST24-FEDER-002033), QREN, Mais Centro—PORC and EU/ERDF. The authors thank all volunteers, technicians, maritime authority officers and fishermen who contributed to this work. The authors would like to thank all the suggestions made by Dr. Fred Wrona and by two anonymous referees.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2016

Authors and Affiliations

  • Lídia Nicolau
    • 1
    • 2
  • Marisa Ferreira
    • 2
    • 3
  • Jorge Santos
    • 1
    • 2
  • Hélder Araújo
    • 1
    • 2
  • Marina Sequeira
    • 4
  • José Vingada
    • 2
    • 5
  • Catarina Eira
    • 1
    • 2
  • Ana Marçalo
    • 1
    • 2
  1. 1.Departamento de Biologia e Centro de Estudos do Ambiente e do Mar (CESAM)Universidade de AveiroAveiroPortugal
  2. 2.Sociedade Portuguesa de Vida Selvagem (SPVS), Departamento BiologiaUniversidade do MinhoBragaPortugal
  3. 3.Departamento Biologia, Centro de Biologia Molecular e Ambiental (CBMA)Universidade do MinhoBragaPortugal
  4. 4.Instituto da Conservação da Natureza e das Florestas (ICNF)LisbonPortugal
  5. 5.Departamento de Biologia e Centro de Estudos do Ambiente e do Mar (CESAM)Universidade do MinhoBragaPortugal

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