Wild dogs and kleptoparasitism

Some misunderstandings

John R. Speakman*, Martyn L. Gorman, Michael G L Mills, Jacobus P. Raath

*Corresponding author for this work

Research output: Contribution to journalComment/debate

5 Citations (Scopus)

Abstract

Seventeen years ago, we published a landmark paper on the energy expenditure of the African Wild dog (Lycaon pictus) (Gorman et al., 1998) using isotope elimination methods that enable quantification of free-living energy demands (Speakman, 1997). Using these data, we mathematically modelled the energy budgets of wild dogs to show that losses of food to kleptoparasites (lions and hyaenas), while apparently small, lead to an exponential increase in both the required hunting time, and daily energy demands. An increase in kleptoparasitism to 25% of kills would require more than 12 h of hunting per day, and would therefore be unsustainable. This showed why wild dogs are particularly vulnerable to local extinction in areas where their main kleptoparasites are abundant. Jongeling & Koetsier (2014) present a critique of our paper, coming to the contrary conclusion that wild dogs are not vulnerable to kleptoparasitism. Their argument is that we made an error in our calculations because we assumed that without kleptoparasitism wild dogs are in energy balance. From this assumption, we calculated the impact of kleptoparasitism using a simple mathematical model. Jongeling & Koetsier (2014) replicated and validated this calculation in their paper, and hence do not dispute that the model is correct. Their criticism instead lies in our parameterization. A critical value in the model is the energy return from hunting. Because dogs expend 15.3 MJ day−1 and are active for on average 3.45 h day−1, then the average return is 4.43 MJ h−1 hunting. In contrast, Jongeling & Koetsier (2014) suggest that wild dogs catch substantially more than this because they also need to feed attendant pups and that wild dogs routinely eat substantially more than their energy requirements. We will consider each of these arguments in turn
Original languageEnglish
Pages (from-to)125-127
Number of pages3
JournalAfrican Journal of Ecology
Volume54
Issue number1
Early online date24 Nov 2015
DOIs
Publication statusPublished - 1 Mar 2016

Fingerprint

kleptoparasitism
dogs
hunting
Lycaon pictus
energy
food loss
Hyaenidae
Panthera leo
energy costs
dog
local extinction
energy requirements
pups
energy balance
energy budget
isotopes
mathematical models
extinction
expenditure
parameterization

ASJC Scopus subject areas

  • Ecology, Evolution, Behavior and Systematics

Cite this

Wild dogs and kleptoparasitism : Some misunderstandings. / Speakman, John R.; Gorman, Martyn L.; Mills, Michael G L; Raath, Jacobus P.

In: African Journal of Ecology, Vol. 54, No. 1, 01.03.2016, p. 125-127.

Research output: Contribution to journalComment/debate

Speakman, John R. ; Gorman, Martyn L. ; Mills, Michael G L ; Raath, Jacobus P. / Wild dogs and kleptoparasitism : Some misunderstandings. In: African Journal of Ecology. 2016 ; Vol. 54, No. 1. pp. 125-127.
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