A continuation of the good news for the Southern Right Whale, from Dr. Peter Best:
The Southern Right Whale population off the Southern Cape coast is responding "optimally" to protection measures, researcher Pete Best said on Monday.
In a statement announcing the start on Tuesday of the latest of a series of annual aerial surveys of the migrant whales, he said this year's survey would be the 28th.
"During this period, 900 individual adult females have been identified, and the birth of some 2 700 calves has been recorded, and estimates of survival rate, age at maturity and calving interval obtained.
"It has also been possible to show that the population has been increasing steadily at seven percent a year throughout," he said.
This figure was based not only on direct census results but also on a population model independent of possible changes in the efficiency of the aerial survey.
"It has been demonstrated that this rate of increase is the maximum possible biologically, indicating that the population is responding optimally to protection," he said.
Best is attached to the Mammal Research Institute of the University of Pretoria, which will carry out the survey.
He said the survey covered a stretch of coast from Nature's Valley near Plettenberg Bay, to Cape Town.
Scientists would use the survey to photograph all the cow-calf pairs seen.
"As Southern Right Whales are individually recognisable from the pattern of wart-like callosities on their head, the photographs taken enable scientists to follow the reproductive history and survival of individual whales over many years," he said.
He said that though there was doubt about exactly how many Right Whales there were in the late eighteenth century when exploitation started, the best available evidence suggested that current numbers were about one sixth of their initial level.
He said the whales started to arrive off the Southern Cape coast in mid-winter, and were normally gone by the end of each year.
Some headed to feeding grounds in the South Atlantic between 40 and 55 degrees of latitude, while others went up the West Coast.
Best said it was possible some headed for the Indian Ocean.
Apparently individual Southern Right Whales calve once every three years.
June 2004 July 2004 August 2004 September 2004 October 2004 November 2004 December 2004 January 2005 March 2005 April 2005 May 2005 June 2005 July 2005 August 2005 September 2005 October 2005 November 2005 December 2005 January 2006 February 2006 March 2006 April 2006 May 2006 June 2006 July 2006 August 2006 September 2006 October 2006 November 2006 December 2006 January 2007 February 2007 March 2007 April 2007 May 2007 June 2007 July 2007 August 2007 September 2007 October 2007 November 2007 December 2007 January 2008 February 2008 April 2008 May 2008 June 2008 July 2008 August 2008 September 2008 October 2008 November 2008 December 2008 January 2009 February 2009 March 2009 April 2009 May 2009 June 2009 July 2009 August 2009 September 2009 October 2009 November 2009 January 2010 February 2010 April 2010 May 2010 June 2010 July 2010 August 2010 September 2010 February 2011 March 2011 May 2013 June 2013