On the success rates of maritime piracy attacks

  • George Ad. PsarrosEmail author
  • Alexander F. Christiansen
  • Rolf Skjong
  • Gjermund Gravir


Today, modern pirates operate both in ports and on the open sea and use state-of-the-art equipment. Their crimes range from simple robbery to murder and hijacking of entire ships for ransom demand. It is the purpose of this paper to investigate the modern piracy trends and the effect of preventive actions taken by the crew of the attacked vessels. By analysing the available statistical material from the International Maritime Organization’s (IMO) monthly piracy reports during the period 2000–2009, it is shown that the attack rates on specific vessel segments and the recorded incidents for each geographical area develop their own trends. Incidents off and around the African continent have resulted to fewer deaths as compared to those in South China Sea and Malacca strait indicating that this area is dominated by more violent attacks against seafarers. However, the African attacks have bigger threatening potential in terms of the weapons used, whereas the inclusion of light weaponry in Asian attacks characterises them ancestors of historical piracy. Over the 10-year investigation period, a shift is observed from acts of robbery to acts of hostage taking and hijacking particularly around and off the East African coast. Estimates of the probability of an attack are provided through logistic regression modelling indicating that the success rate decreases with vessel size. It is also shown that the attacks are emphasised on specific vessel types for example chemical and oil tankers. The importance of a heightened vigilant crew in reducing the probability of a successful attack is pointed out by the analysis’ results. It is found that pirates are aiming at successful attacks regardless of their tactics and the success rate becomes higher as the pirates’ capability is improved. Additionally, the success probability of an attack is decreased as the act’s difficulty is increased, i.e. less success for hijacking rather than robbery.


Maritime security and piracy Merchant ships Attack probability Piracy success rate Piracy modus and capability Logistic regression 



The work reported in this paper has been carried out under the SECTRONIC project, 7th FP, CP-GA No. 218245, with partial funding from the European Commission as well as the DNV R&I strategic research programmes. The authors would like to thank Anna Ivinska, Ingar Bergh and Tore Longva (DNV) for the data support, Øyvind Endresen, Evangelos Boutsianis and Morten Bremer Mærli (DNV) for their valuable comments. The opinions expressed are those of the authors and should not be construed to represent the views of the SECTRONIC partnership or Det Norske Veritas A/S.


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Copyright information

© Springer Science + Business Media, LLC 2011

Authors and Affiliations

  • George Ad. Psarros
    • 1
    Email author
  • Alexander F. Christiansen
    • 1
  • Rolf Skjong
    • 1
  • Gjermund Gravir
    • 1
  1. 1.Det Norske Veritas ASHøvikNorway

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