Whales may be host to blood sucking fish

A study in the northern part of the Atlantic Ocean has suggested that the blood-sucking sea lampreys, Petromyzon marinus, may be feeding on whales in the region.


Blood sucking lampreys possibly feeding on whales’ blood

This parasitic species was photographed by observers in the region to be leeching onto specific areas on the whale’s body, using their mouths which function like a suction funnel.  Prior to initial results in 2004, the lamprey was suggested to only cling onto these whales for transport purposes. However, further research in 2011 led to the release of photographs that have shown clear indication of whales having bloody wounds where the lamprey had just detached itself.

Adding onto this, scrape marks left by the lamprey were present along the whale’s body, in opposite direction of the forward swimming whale and flow of water. This suggests that the lamprey was intentionally moving along the whale’s body, giving more reason to believe that it was feeding on the whale, as this activity would require extensive energy.

It is not yet discovered if these lampreys have a preferred spot on the whales for feeding, but observation results have suggested that certain areas on the whales may provide better access to blood, in comparison to other parts of the body. Perhaps the lampreys may well be on their way to discovering where these areas may be, before scientists do.



Nichols, O. C., & Hamilton, P. K. (2004). Occurrence of the parasitic sea lampreyPetromyzon marinus on western North Atlantic right whales Eubalaena glacialis. Environmental biology of fishes, 71(4), 413-417.

Nichols, O. C. and Tscherter, U. T. (2011), Feeding of sea lampreys Petromyzon marinus on minke whales Balaenoptera acutorostrata in the St Lawrence Estuary, Canada. Journal of Fish Biology, 78: 338–343.


“Blood sucking fish feed on whales” by Ella Davies. BBC Earth News, (03 Jan 2011). URL: http://news.bbc.co.uk/earth/hi/earth_news/newsid_9281000/9281424.stm (accessed on 09 Apr 2013)