Have you ever wondered how scientists count whales and how accurate their population estimates are?
The June issue of ‘Significance’ a journal focused on statistics has an article by Philip Hammond, a former Chairman of the Scientific Committee of the International Whaling Committee (IWC), explaining some of the techniques for estimating population numbers and it includes comment that:
“The minke whale is the most abundant species of baleen whale, with a world population of hundreds of thousands, maybe as much as a million. In recent years most whales killed for commercial purposes have been minkes. In the North Atlantic about 600 a year have been taken by Norway under objection to the moratorium and about 30 to 40 by Iceland under special permit. Japan annually takes about 450 minke whales in the Southern Ocean and about 150 in the North Pacific under special permit. These catches are small relative to the estimated numbers of whales and are unlikely to have an adverse impact on populations.
The number of blue whales in the world, however, is only a few thousand. In the Southern Ocean an estimated 400 to 1400 remain from a population that probably once numbered about 750 000. Blue whales have been protected since the 1960s but they have very low rates of increase and it will be a long time before we know whether or not they will recover from the devastating exploitation of the 20th century.”
So what is limiting the recovery of blue whale numbers?
I’ve been told that minke whales compete with blue whales and that high minke whale population numbers could be impacting on the recovery of blue whales? If this is the case, could harvesting of minke whales by the Japanese in the Antarctic help recovery of the depressed blue whale population?
After posting this note, I received an email from a reader with comment that: If blue whales are failing to recover it may be because of the various problems associated with small population size. …The contention that Blue Whale recovery in the Antarctic is being inhibited by prey competition from Minke Whales has little basis in existing data. …although the Blue Whale’s dependence upon a single food source (krill) is somewhat offset by the latter’s great abundance, this stenophagy would make the species more vulnerable in the event of a major decline in prey. 
Ann Novek recently sent me a note explaining that: “There are no direct actions against Norwegian whaling anymore from Greenpeace’s side, the new tactic is dialogue. Norwegian whaling has silenced a lot since the turbulent 90’s.”
According to Norwegian Greenpeace activist Truls Gulowsen speaking three years ago,
last year’s a quota of 600 minke whales posed no threat to minke whales in the north east Atlantic. He has also suggested that campaigns against whaling can distract from the real threats to the coast, including overfishing and the risk of oil industry pollution.
What are the most significant threats to the world’s whales? Which whale species really need ‘saving’ and how can they be best ‘saved’?
 I’ve not seen the supporting studies/literature. If you have links/references please post as a comment or send to email@example.com
 From Clapham, P.J., Young, S.B. & Brownell, R.L. Jr. 1999. Baleen whales: conservation issues and the status of the most endangered populations. Mammal Review 29: 35-60. http://whale.wheelock.edu/archives/ask01/att-0020/01-blue.rtf
 Thanks to Ann for sending the note with information and links including: ‘Norway’s Disputed Whaling Season Opens’ Monday April 18, 2005, By DOUG MELLGREN, Associated Press Writer, OSLO, Norway, &
‘Redde verdenshavene’ (Save the Oceans) and ‘Hvalfangst’ ( Whaling) at http://www.greenpeace.org/norway/campaigns/hav/hvalfangst (Only in Norwegian), & Truls Gulowsen’s statement “that a quota of 600 minke whales poses no threat to the minke whale population” from the magasine Folkevett at
http://www.folkevett.no/index.php?back=1&artikkelid=1079 ( only in Norwegian).