A growth cost of experimentally induced conspicuous coloration in first-year collared lizard males

Abstract

I used painted first-year collared lizard males in the field to test the hypothesis that conspicuous coloration imposes a growth cost, either because it makes lizards less cryptic to their prey or because conspicuous color attracts predators forcing increased refuging by lizards. To make males more conspicuous, I painted them green and yellow to match hues of older territorial males, made another group inconspicuous by painting males brown like females, and painted a control group with water. I then compared rates of travel, the frequency, and the percentage of strikes on prey that were successful. I recaptured males periodically to record cloacal and substrate temperatures, to measure growth rate, and to retouch paint. Time spent refuging, travel rate, and both cloacal and substrate temperatures were similar in the 3 groups. Males painted conspicuously had slower growth than males in the other treatment groups. Inconspicuous males initiated strikes on prey more than 4 times more frequently than conspicuous males, and the number of strikes that resulted in prey capture was higher in inconspicuous males, suggesting that conspicuous coloration reduces foraging opportunities because it makes first-year males more visible to their prey. Rapid growth during the first season is necessary for collared lizard males to become large enough to compete for breeding territories as 2 year olds. Therefore, conspicuous coloration may develop gradually in first-year collared lizard males to maintain crypsis, which promotes food intake sufficient for rapid growth to large size that has important consequences for future reproductive success.

Conspicuousness of Dickerson's collared lizard (Crotaphytus dickersonae) through the eyes of conspecifics and predators

“…Recently, Baird (2008) demonstrated that femalecoloured yearling male C. collaris, painted to resemble more conspicuous adult males, grew significantly more slowly than did control yearling males (painted brown or painted with water). The results showed that the more conspicuously painted young males made fewer attempts to attack prey and that, when they did attack, they were less successful than control males.…”

“…The results showed that the more conspicuously painted young males made fewer attempts to attack prey and that, when they did attack, they were less successful than control males. Baird (2008) attributed the slower growth rates in the experimental males to a reduction in 'aggressive crypsis ' (Endler, 1981); that is, being more conspicuous resulted in early detection by prey (Grether & Grey, 1996). Thus, conspicuous ornamental coloration should be particularly costly for collared lizards, which are predators as well as prey.…”

“…Yet, with the exception of aposematism (Mappes, Marples & Endler, 2005) conspicuous coloration typically appears disadvantageous for avoiding detection by predators (Endler, 1978;Slagsvold, Dale & Kruszewicz, 1995;Johannesson & Ekendahl, 2002;Godin & McDonough, 2003;Sherratt & Beatty, 2003;Stuart-Fox et al, 2003Merilaita & Lind, 2005;Husak et al, 2006;Stuart-Fox, Whiting & Moussalli, 2006;Stuart-Fox, Moussalli & Whiting, 2008; but see also Götmark, 1996) and prey (Grether & Grey, 1996;Baird, 2008). Most animal colour patterns therefore appear to represent a local balance between the social and reproductive advantages of sexually-selected ornamental coloration and the cost of increased visibility to unintended audiences (Endler, 1992;Stuart-Fox & Ord, 2004;.…”

Phenotypic plasticity of life history traits in relation to reproductive strategies in Boa constrictor occidentalis

“…Therefore, as Bonnet et al (2000) suggest for Vipera aspis, an intermediate body size would balance ecological and reproductive advantages, maximizing the reproductive output. Body size has a strong influence on reproductive output but also on the ecological consequences for an organism, since overall energy balance is strongly affected by body size (Baird 2008). High maintenance requirements of larger individuals may increase their vulnerability in low-resource habitats.…”

“…Energy allocation to growth and reproduction determines life history structure (Stearns 1992;Baird 2008). Body size is a key life-history trait because it determines many aspects of the biology of organisms and their interaction with the environment (Naganuma and Roughgarden 1990).…”