Integument coloration signals reproductive success, heterozygosity, and antioxidant levels in chick-rearing black-legged kittiwakes

Abstract

Carotenoid pigments are important for immunity and as antioxidants, and carotenoid-based colors are believed to provide honest signals of individual quality. Other colorless but more efficient antioxidants such as vitamins A and E may protect carotenoids from bleaching. Carotenoid-based colors have thus recently been suggested to reflect the concentration of such colorless antioxidants, but this has rarely been tested. Furthermore, although evidence is accruing for multiple genetic criteria for mate choice, carotenoid-based colors have rarely been shown to reflect both phenotypic and genetic quality. In this study, we investigated whether gape, tongue, eye-ring, and bill coloration of chick-rearing black-legged kittiwakes Rissa tridactyla reflected circulating levels of carotenoids and vitamins A and E. We further investigated whether integument coloration reflected phenotypic (body condition and fledging success) and genetic quality (heterozygosity). We found that the coloration of fleshy integuments was correlated with carotenoid and vitamin A levels and fledging success but only in males. Furthermore, the coloration of tongue and eye-ring was correlated with heterozygosity in both males and females. Integument colors might therefore be reliable signals of individual quality used by birds to adjust their parental care during the chick-rearing period.

Integument colouration in relation to persistent organic pollutants and body condition in arctic breeding black-legged kittiwakes (Rissa tridactyla)

“…Secondly, body condition was positively related to hue and brightness for gapes and tongue implying that these colour parameters are sensitive to current nutritional conditions and health of individuals, as previously found in this species (Doutrelant et al, 2013 in press;Leclaire, 2010;Leclaire et al, 2011aLeclaire et al, , 2011b.…”

“…In addition, we also examined the correlates between body condition and integument colouration since body condition could reflect individual quality in this species. According to previous studies (Doutrelant et al, 2013 in press;Leclaire, 2010;Leclaire et al, 2011aLeclaire et al, , 2011b, we predicted that females with a better body condition would display the most colourful integuments.…”

“…However, this method has already been investigated on black-legged kittiwakes (Leclaire, 2010;Leclaire et al, 2011aLeclaire et al, , 2011b) and information obtained from digital pictures is still very useful as it reveals patterns and effects of biological meaning (Alonzo-Alvarez et al, 2004;Bortolotti et al, 2003;Kilner, 1997;Leclaire, 2010;Leclaire et al, 2011aLeclaire et al, , 2011bMassaro et al, 2003;Mougeot et al, 2007;Pérez-Rodríguez and Viñuela, 2008;Pérez et al, 2010b). Furthermore, using photography rather than spectrometry might be advantageous because digital photography is a much easier method for quantifying colouration of wet, hard to reach, and irregular surfaces such as gapes, irises and bills (Montgomerie, 2006).…”

“…Both sexes show intense carotenoid-based colouration during the breeding season (Doutrelant et al, 2013 in press;Leclaire et al, 2011a), including the red eyering, red/ orange gapes, orange tongue and yellow bill. Recent studies have shown that these integuments could reflect individual quality in both sexes (Doutrelant et al, 2013 in press; Leclaire, 2010; Leclaire et al, 2011aLeclaire et al, , 2011b. In the Arctic, black-legged kittiwakes are exposed to POPs which are known to act as endocrine disruptors and to have a negative impact on reproductive performances (Bustnes et al, 2003(Bustnes et al, , 2008Helberg et al, 2005;Nordstad et al, 2012).…”

Semiochemical compounds of preen secretion reflect genetic make-up in a seabird species

“…Kittiwakes are thus expected to choose their mate according to heterozygosity, as found in other birds such as wire-tailed manakins Pipra filicauda [36], blue tits Cyanistes caeruleus [37] and house sparrows Passer domesticus [34]. In kittiwakes, integument coloration reflects heterozygosity [42]. Odour may thus be one of the cues used by birds to assess the genetic quality of their potential partners.…”