Avian Ultraviolet Vision And Frequency-Dependent Seed Preferences

It is well established that ultraviolet sensitivity plays an important role in the visually guided behaviour of birds. From a foraging perspective, evidence now exists that ultraviolet wavelengths are used by birds when foraging for insects, berries, seeds and mammals. Here, we present the results of two laboratory experiments that test the effect of removing […]

Is the ultraviolet waveband a special communication channel in avian mate choice?

There is growing evidence that ultraviolet (UV) wavelengths play an important role in avian mate choice. One of the first experiments to support this idea showed that female zebra finches (Taeniopygia guttata) prefer UV-reflecting males to males whose ultraviolet reflection has been removed. The effect was very strong despite little or no UV reflection from […]

Ultraviolet colour perception in European starlings and Japanese quail

Whereas humans have three types of cone photoreceptor, birds have four types of single cones and, unlike humans, are sensitive to ultraviolet light (UV, 320-400 nm). Most birds are thought to have either a violet-sensitive single cone that has some sensitivity to UV wavelengths (for example, many non-passerine species) or a single cone that has […]

Ultraviolet Reflection of Berries Attracts Foraging Birds. A Laboratory Study with Redwings (Turdus iliacus) and Bilberries (Vaccinium myrtillus)

Unlike humans, birds perceive ultraviolet (UV) light (320 to 400 nm), a waveband which is known to play a role in avian mate choice. However, less attention has been paid to the role of UV light in avian foraging. Some blue, violet and black berries reflect UV light. The colour of berries might be an […]

True colours

It’s only when you begin to see the world as birds do — detecting light in the ultraviolet spectrum — that the full subtlety of their behaviour is revealed. Rex Dalton catches a glimpse.

Retinal Spectral Sensitivity, Fur Coloration, and Urine Reflectance in the Genus Octodon (Rodentia): Implications for Visual Ecology

Purpose: To determine the eye’s spectral sensitivity in three species of the genus Octodon (order Rodentia; infraorder Caviomorpha), O. degus, O. bridgesi, and O. lunatus, as well as the spectral properties of the animals’ fur and urine and of objects in their habitat. The genus is endemic in Chile and contains species with different habitats […]

Voluntary exposure of some western-hemisphere snake and lizard species to ultraviolet-B radiation in the field: how much ultraviolet-B should a lizard or snake receive in captivity?

Abstract 10.1002/zoo.20255.abs Studies of voluntary exposure to ultraviolet-B (UVB) radiation from the sun in the field were conducted in the southern US and Jamaica for 15 species of lizards and snakes occupying various habitats. Species were sorted into four zones of UVB exposure ranging from a median UV index of 0.35 for zone 1 to […]

Effect of supplementary ultraviolet lighting on the behaviour and corticosterone levels of Japanese quail chicks

Most birds have visual sensitivity to ultraviolet (UV) wavelengths, and this sensitivity appears to play a role in their colour vision. Artificial lighting is normally deficient in UV wavelengths. Hence, there may be welfare implications for captive birds kept under such lighting. We investigated whether the absence of UV wavelengths during rearing adversely affects Japanese […]

Geographic variation in beak colouration in gentoo penguins Pygoscelis papua

Ornamental colouration is often due to carot-enoid pigments and varies inter- and intra-specifically. This paper reports on variation in beak colour of the gentoo penguin, Pygoscelis papua, corresponding to different geographical locations along a latitudinal gradient in the Antarctic Peninsula (from King George Island (62815 0 S– 58837 0 W) to Ronge´Island (64840 0 S–62840 […]

Studies on UV reflection in feathers of some 1000 bird species: are UV peaks in feathers correlated with violet-sensitive and ultraviolet-sensitive cones?

Nine hundred and sixty-eight bird species, covering all orders, were studied in search of distinctive ultraviolet reflections. All species in the following orders were completely surveyed: Struthioniformes, Tinamiformes, Craciformes, Turniciformes, Galbuliformes, Upupiformes, Coliiformes, Apodiformes and Musophagiformes. The coloured plumage regions in particular exhibited high proportions of UV-reflecting feathers. Bird orders with species which are believed […]