Charles Krebs

Charles Joseph Krebs FRSC FAA FRZS (born 17 September 1936) is a professor emeritus of population ecology in the University of British Columbia Department of Zoology.[1] He is also Thinker-in-residence at the Institute for Applied Ecology at the University of Canberra, Australia. He is renowned for his work on the fence effect, as well as his widely used ecology textbook Ecology: The Experimental Analysis of Distribution and Abundance.[2]

Charles Krebs
Charles Krebs and Dawn Bazely at Judy Myers' retirement celebration in 2007 (cropped).jpg
Charles Krebs (left) with Dawn Bazely, in 2007
Charles Joseph Krebs

(1936-09-17) 17 September 1936 (age 84)
Alma mater
Known forEcology: The Experimental Analysis of Distribution and Abundance
Scientific career
FieldsPopulation ecology
ThesisThe lemming cycle at Baker Lake, N.W.T., during 1959-61 (1962)
Doctoral advisorDennis Chitty
Other academic advisorsIan McTaggart-Cowan
InfluencedStan Boutin


Krebs was interested mostly in smaller mammal ecology and in 1965 conducted an experiment on voles.[3] He fenced in an area of grassland in an Indiana pasture about the size of a soccer field and observed what happened to the population of voles living inside the fenced area.[3] This was when he founded the widely known "Fence Effect".[3] Within a year of living in the fenced area the voles had increased by about five times, which is much more than they would in an unfenced area.[3] He then observed that the population experienced a crash, just like the unfenced populations do.[3] Krebs believed this was due to social behaviour among the voles and could be applied to other animals like them.[3] The voles had no place to migrate therefore the final crash seemed to stem from an increase of competition, aggressive behaviour, and decreased resources.[3]

Krebs also worked in British Columbia and Northern Canada for over 40 years to look at cyclic populations of mammals.[4] during this time he was able to transform the field of ecology from a descriptive science to an experimental discipline.[4] For 20 years he studied the 10-year population cycle of snowshoe hares and their predators in the Yukon.[3] He found that the population size of the snowshoe hares is regulated by predators such as the lynx, coyote, great horned owls and goshawks.[3] 90% of their deaths were found to be due to these predators and almost none because of starvation and disease.[3]

During his career, Krebs made the case for basic research.

If someone asks me if my work has economic benefit I say absolutely none. And then they ask 'well why are you doing it' and I say that we need to understand the world we live in. It enriches our lives.

— Charles Krebs, Q&A: Dr. Charles Krebs on a lifetime of science, Canadian Geographic[5]

Select awards and recognitionEdit


  1. ^
  2. ^ a b
  3. ^ a b c d e f g h i j GCS Research Society. 2015.
  4. ^ a b 1. Ecological Society of America. 2002. Eminent Ecologist Award.
  5. ^ Doyle, Sabrina (27 July 2015). "Q&A: Dr. Charles Krebs on a lifetime of science". Canadian Geographic. Retrieved 10 May 2020.
  6. ^ "Royal Zoological Society of New South Wales". Royal Zoological Society of New South Wales. Archived from the original on 15 March 2017. Retrieved 15 March 2017.

External linksEdit