Use of blubber levels of progesterone to determine pregnancy in free-ranging live cetaceans
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We tested the possibility of measuring progesterone levels in bubbler samples collected from free-ranging live bottlenose dolphins (n = 11) and long-finned pilot whales (n = 2) as a tool to evaluate the pregnancy status of individuals. Samples were collected during January 2004 and September–October 2005 in the Strait of Gibraltar and Gulf of Cadiz and used for sex-determination by genetic methods (skin samples) and for quantification of progesterone levels by enzyme immunoassay. Photo-identification tracking of females after taking the biopsy was used to observe the presence of newborns and, in this way, to determine if the female was pregnant at the time of sampling. Mean progesterone levels from pregnant bottlenose dolphins (n = 2) were around 9 times higher than those from non-pregnant females (n = 9), with no overlap between concentration ranges demonstrating that this method could constitute an effective tool for determining pregnancy in wild populations of bottlenose dolphins and other cetacean species.
KeywordsProgesterone Level Bottlenose Dolphin Progesterone Concentration Minke Whale Gray Whale
Our study was made possible due to the financial support received during several cetacean campaigns in the Iberian Peninsula. We thank the Foundation Loro Parque, the Foundation Biodiversidad and CEPSA. This work would not have been possible without the help of different volunteers and researchers, especially to R. Esteban, N. Seller Fernandez, Z. Munilla, Y. Yaget, C. Corbella, C. Jiménez, D. Alarcon, M. Carbó, S. Villar, and N. Pérez.
- García-Tíscar S (2010) Interacciones entre delfines mulares (T. truncatus), orcas (Orcinus orca), y pesquerías en el mar de Alborán y Estrecho de Gibraltar. PhD thesis, Universidad Autónoma de Madrid. Available at www.circe.info
- Jiménez Torres C (2009) Tasa de supervivencia, abundancia y residencia del delfín mular en el estrecho de Gibraltar. Master’s thesis, Universidad de Barcelona. Available at www.circe.info
- Perryman WL, Lynn MS (2002) Evaluation of nutritive condition and reproductive status of migrating gray whales (Eschrichtius robustus) based on analysis of photogrammetric data. J Cetacean Res Manage 4(2):155–164Google Scholar
- Rolland RM, Hamilton PK, Kraus SD, Davenport B, Gillet RM, Wasser SK (2006) Faecal sampling using detection dogs to study reproduction and health in North American right whales (Eubalaena glacialis). J Cetacean Res Manage 8:121–125Google Scholar
- Smit AM (2003) Age determination and establishment of reproductive condition from marine mammal biopsy sampling. Department of Conservation Wellington, New ZealandGoogle Scholar