Common bottlenose dolphin

Pregnancy in Tursiops truncatus is usually confirmed by blood tests (progesteron) and ultrasound examination.In this way it is possible to follow the normal development of the fetus. Since 1992 , Alessandro Bortolotto has been committed to develop a behavioral non-intrusive method aimed at determining the delivery date. This method has proven its reliability and superiority over the above mentioned methods on numerous occasions : Aquarium of Cattolica (1992 , along with another colleague), Delphinursey Catholic (1993) , Aquarium of Genoa (1994) , Parc Asterix ( 1996) Delphinursey Catholic (1997) , Parc Asterix (1999) , Gardaland (2001) , Gardaland (2008 /9) and Oltremare (2010). It has also been used in a reduced/modified form by other facilities(Zoomarine Portugal, Duisburg Zoo, National Aquarium in Baltimore, Maryland, USA).

Over the years, technological improvements combined with an enhanced medical skills and management have greatly increased the odds of neonatal survival in captivity. Nonetheless it the support of a well-structured scientific/managerial project provides critical elements essential to ensure the proper management of pregnancy and the postpartum period.

During the study period the pregnant female is observed with standard behavioral methods ('focal animal sampling' and 'ad libitum sampling technique' with 'continuous recording' as sampling method). The observation period we examined is the one from 0:00 to 06:00 AM (solar time) .

The behavior that we normally study is the so-called ' flexion', as described in the 1950s.

Our studies have been presented at numerous conferences since 1993 :

  • 1993 IMATA (International Marine Animal Trainers Association) , Hawaii (USA) ;
  • 1995 EAAM (European Association for Aquatic Mammals ) Symposium, Nuremberg ( Germany) ;
  • 1997 EAAM Symposium, Duisburg (Germany) ;
  • 1997 Third National Meeting on Cetaceans, Napoli ;
  • 1998 EAAM Symposium, Tampere ( Finland ) ;
  • 2000 EAMM Symposium, Benidorm (Spain) ;
  • 2009 EAAM Symposium, Bahar ic Cagaq (Malta)


Lenzi, R. and Bortolotto, A., (1993)
Monitoring a pregnant bottlenose dolphin (Tursiops truncatus) 24 hours a day for a long time; there may be an easier way to do it!
Proc. of the 1993 I.M.A.T.A. Annual Conf., Hawaii

Bortolotto, A., Benoldi, C., Bonsignori, B., Gnone, G., (1995)
Observation of a bottlenose dolphin (Tursiops truncatus) during the pregnancy
Poster at 23rd EAAM Annual Symposium, Nuremberg, 1995

Bortolotto, A., Pastore, V., Sironi, A., Mercera, B., (1997)
Delivery determination by means of behavioural observations of three female bottlenose dolphins (Tursiops truncatus) during the pregnancy.
Poster presentation at 25th EAAM Annual Symposium, Duisburg, Germany

Bortolotto, A., (1997)
Flessioni: Un metodo potente e affidabile per la determinazione del parto in Tursiops truncatus in modo accurato.
Terzo Convegno Nazionale sui Cetacei, Napoli, 5-6 dicembre 1997

Bortolotto, A., (1998)
Flexions: a reliable tool for the delivery determination in the bottlenose dolphin (Tursiops truncatus) in an accurate way.
Video-presentation at 26th EAAM Annual Symposium, Tampere, Finland

Pastore, V., Mercera, B., Bortolotto, A. (2000)
The husbandry of pregnant bottlenose dolphins: a behavioural approach.
Presentation at the 28th EAAM Annual Symposium, Benidorm, Spain

Barros, D.G., Guglielmi, E., Saviano, P., Simoni, R., Redivo, V.T., Arzocco, M., Di Naro, O., Russo, W. and Bortolotto, A. (2009)
A multidisciplinary approach to the management of pregnancy, parturition and post-parturition in Tursiops truncatus.
Presentation at the 37th EAAM Annual Symposium, Malta

People who participated:

Martina Arzocco
Carla Benoldi
Barbara Bonsignori
Alessandro Bortolotto
Olimpia Di Naro
Guido Gnone
Roberto Induni
Renato Lenzi
Sara Mainardi
Valerio Manfrini

Mihaela Marceljak
Silvia Parasecoli
Valeria Pastore
Cristina Pilenga
Walter Russo
Arianna Sironi