title: What enables size-selective trophy hunting of wildlife?
abstract: Although rarely considered predators, wildlife hunters can function as important ecological and evolutionary agents. In part, their influence relates to targeting of large reproductive adults within prey populations. Despite known impacts of size-selective harvests, however, we know little about what enables hunters to kill these older, rarer, and presumably more wary individuals. In other mammalian predators, predatory performance varies with knowledge and physical condition, which accumulates and declines, respectively, with age. Moreover, some species evolved camouflage as a physical trait to aid in predatory performance. In this work, we tested whether knowledge-based faculty (use of a hunting guide with accumulated experience in specific areas), physical traits (relative body mass [RBM] and camouflage clothing), and age can predict predatory performance. We measured performance as do many hunters: size of killed cervid prey, using the number of antler tines as a proxy. Examining ∼ 4300 online photographs of hunters posing with carcasses, we found that only the presence of guides increased the odds of killing larger prey. Accounting for this effect, modest evidence suggested that unguided hunters presumably handicapped with the highest RBM actually had greater odds of killing large prey. There was no association with hunter age, perhaps because of our coarse measure (presence of grey hair) and the performance trade-offs between knowledge accumulation and physical deterioration with age. Despite its prevalence among sampled hunters (80%), camouflage had no influence on size of killed prey. Should these patterns be representative of other areas and prey, and our interpretations correct, evolutionarily-enlightened harvest management might benefit from regulatory scrutiny on guided hunting. More broadly, we suggest that by being nutritionally and demographically de-coupled from prey and aided by efficient killing technology and road access, wildlife hunters in the developed world might have overcome many of the physical, but not knowledge-based, challenges of hunting.
authors.affiliation: Department of Geography, University of Victoria, Victoria, BC, Canada; Raincoast Conservation Foundation, Sidney, BC, Canada.
authors.forename: Chris T
authors.initials: CT
authors.lastname: Darimont
authors.affiliation: Department of Geography, University of Victoria, Victoria, BC, Canada; Raincoast Conservation Foundation, Sidney, BC, Canada.
authors.forename: K Rosie
authors.initials: KR
authors.lastname: Child
mesh_terms: D000328:Adult; D000818:Animals; D015992:Body Mass Index; D003020:Clothing; D003258:Consumer Behavior; D006801:Humans; D008297:Male; D010781:Photography
references.citation: Proc Biol Sci. 2012 Nov 7;279(1746):4407-16
references.pmid: 22951744
references.citation: Med Sci Sports Exerc. 2000 Sep;32(9 Suppl):S498-504
references.pmid: 10993420
references.citation: Philos Trans R Soc Lond B Biol Sci. 2009 Feb 27;364(1516):423-7
references.pmid: 18990674
references.citation: Ann N Y Acad Sci. 1987;499:29-46
references.pmid: 3300488
references.citation: J Hum Evol. 2006 Nov;51(5):454-70
references.pmid: 16797055
references.citation: Proc Biol Sci. 2013 Mar 13;280(1758):20130064
references.pmid: 23486439
references.citation: Nature. 2003 Dec 11;426(6967):655-8
references.pmid: 14668862
references.citation: Am J Clin Nutr. 2005 Feb;81(2):341-54
references.pmid: 15699220
references.citation: Demography. 2009 Feb;46(1):27-41
references.pmid: 19348107
references.citation: J Hum Evol. 2002 Jun;42(6):639-57
references.pmid: 12069505
references.citation: Ecol Appl. 2007 Sep;17(6):1607-18
references.pmid: 17913127
references.citation: Proc Natl Acad Sci U S A. 2009 Jun 16;106 Suppl 1:9987-94
references.pmid: 19528656
references.citation: Behav Processes. 2005 Feb 28;68(2):145-63
references.pmid: 15686825
references.citation: Ecol Lett. 2009 Dec;12(12):1347-56
references.pmid: 19780789
references.citation: Conserv Biol. 2007 Feb;21(1):36-47
references.pmid: 17298509
references.citation: Proc Natl Acad Sci U S A. 2010 Apr 6;107(14):6370-5
references.pmid: 20308547
references.citation: PLoS One. 2011 Jan 25;6(1):e16098
references.pmid: 21283573
references.citation: Proc Natl Acad Sci U S A. 2009 Jan 20;106(3):952-4
references.pmid: 19139415
references.citation: Epidemiol Rev. 2007;29:6-28
references.pmid: 17510091
references.citation: Proc Biol Sci. 2011 May 7;278(1710):1373-80
references.pmid: 20961899
references.citation: Acta Diabetol. 2003 Oct;40 Suppl 1:S130-3
references.pmid: 14618452
references.citation: Psychol Rev. 1976 Mar;83(2):157-71
references.pmid: 769017