How many beluga whales are there?

Counting belugas is not an easy task! That said, in order to closely monitor the situation, it is essential that we keep track of the size and the rate of change of this endangered population.

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  • Pod of beluga whales
  • Photo credit: © GREMM

To go through the looking glass

DSince 1973, scientists with Fisheries and Oceans Canada and independent researchers have been conducting regular aerial surveys of the beluga population in the St. Lawrence.

In short

Surveys taken between 1973 and 1985 estimated the number of belugas in the St. Lawrence to be approximately 500 individuals, or barely 10 % of the population of the end of the 1800s. Surveys conducted between 1988 and 2000 estimated the population to be somewhere between 500 and 700. Unfortunately, these results cannot be compared because different methodologies were used. It is therefore impossible to verify whether the population has increased or is stable. However, it appears unlikely that the population is in decline.

Good news

Up until now, the correction factor used to obtain estimates, which would include submerged belugas invisible during the aerial surveys, was 15 %. This correction factor was re-evaluated upwards. By applying a correction factor of 109 %, data from the most recent surveys set estimates at about 1100 belugas. Of course, this revision does not mean that the population has grown. It simply means that we underestimated the number of belugas in the St. Lawrence in the past, which is good news!


Scientific papers

Bailey, R. et N. Zinger. 1995. Plan de rétablissement de la population des bélugas du Saint-Laurent. Fonds mondial pour la nature et Pêches et Océans Canada, Mont-Joli, Québec.

Béland, P., R. Michaud et D. Martineau. 1987. Recensements de la population de bélugas (Delphinapterus leucas) du Saint-Laurent par embarcations en 1985. Rapport présenté au ministère des Pêches et des Océans du Canada.

Comité sur le rétablissement du béluga du Saint-Laurent. 1998. Mise en oeuvre du plan de rétablissement du béluga du Saint-Laurent : 1996-1997. Fons mondial pour la nature et Pêches et Océans Canada, Mont-Joli, Québec.

Gosselin, J.-F., V. Lesage et A. Robillard. 2001. Population index estimate for the beluga of the St Lawrence River Estuary in 2000. Document de recherche 2001/049 du secrétariat canadien de consultation scientifique du Ministère des Pêches et Océans Canada. 21 p.

Kingsley, M. C. S. 1993. Census, trend, and status of the St. Lawrence beluga population in 1992. Canadian Technical Report of Fisheries and Aquatic Sciences 1938.

Kingsley, M. C. S. 1996. Estimation d’un indice d’abondance de la population de bélugas du Saint-Laurent en 1995. Rapport Technique Canadien des Sciences Halieutiques et Aquatiques 2117.

Kingsley, M. C. S. 1998. Population index estimates for the St. Lawrence belugas, 1973-1995. Marine Mammal Science 14(3) : 508-530.

Kingsley, M.C.S. 1999. Population indices and estimates for the belugas of the St. Lawrence Estuary. Canadian Technical Report of Fisheries and Aquatic Sciences 2266 : vii + 27pp.

Kingsley, M. C. S. et I. Gauthier. 2002. Status of the belugas of the St Lawrence estuary, Canada. NAMMCO Scientific Publications 4:239-258.

Kingsley, M. C. S. et M. O. Hammil. 1991. Photographic census surveys of the St. Lawrence beluga population, 1988 and 1990. Canadian Technical Report of Fisheries and Aquatic Sciences 1776.

Lesage, V. et M. C. S. Kingsley. 1998. Updated status of the St. Lawrence River population of the beluga, Delphinapterus leucas. Canadian Field-Naturalist 112(1) : 98-114.

Lynas, E. M. 1988. Transect estimators of cetacean abundance: theory and practice. Scientific Commitee Meeting of the International Whaling Commission, San Diego.

Michaud, R et P. Béland. 1999. Looking for Trends in the Endangered St. Lawrence Beluga Population. Manuscript soumis pour publication.

Pippard, L. 1985. Status of the St. Lawrence River population of beluga, Delphinapterus leucas. Canadian Field-Naturalist 99(3) : 438-450.

Reeves, R. R. et E. Mitchell. 1984. Catch history and initial population of white whales (Delphinapterus leucas) in the River and Gulf of St. Lawrence, Eastern Canada. Le naturaliste Canadien 111: 63-121.

Sergeant, D. E. et W. Hoek. 1988. An update of the status of white whales Delphinapterus leucas in the Saint Lawrence Estuary, Canada. Biological Conservation 45: 287-302.