Sentence examples for beak colour from inspiring English sources
In females, beak colour, body size, fat deposition and choice chamber behaviour showed significant inbreeding depression.
In males, we found strong negative effects of inbreeding on song rate, beak colour, body size and choice chamber attractiveness, whereas body condition, fat deposition, song structure and plumage ornaments were unaffected.
The beak colour of all subjects was assessed during fall.
Male and female beak colour was scored subjectively on a scale ranging from 0 (light orange) to 6 (dark red) using Munsell colour chips.
However, neither differences in song rate (t = −1.0, P = 0.34) nor in beak colour (t = 0.9, P = 0.40) explained the occurrence of extra-pair copulations.
This is also when song learning [28], moult into secondary adult plumage and the transition of beak colour from the black in juveniles to orange in adults occurs [20].
In parts of Spain, studies have shown that the pigment is based on astaxanthin obtained from an introduced species of crayfish (Procambarus clarkii) and the bright red beak colours show up even in nestlings, in contrast to the duller beaks of young white storks elsewhere.
We also quantified the extension of carotenoid and melanic coloration in various body parts, and categorized the patterns of pigmentation and the colour of beak and legs.
Eye rings and beaks won't change colour on Continental birds until they return home.
The single-known male specimen may have been immature, judged on the colour of its beak, and this may also explain the absence of the red patch.
Add some orange-reddish colour to the beak.
