Bill Morphology of Ibises Suggests a Remote-Tactile Sensory System for Prey Detection

Microanatomy of passerine hard‐cornified tissues: Beak and claw structure of the black‐capped chickadee (Poecile atricapillus)

“…As expected, we observed Herbst corpuscles throughout the dermis of the chickadee beak and claw, but only singly or in small clusters. These mechanoreceptors were less densely packed than those observed in other species reported to have a bill tip organ, including various shorebirds, ducks, geese, and parrots (Krogis,1931; Zweers and Wouterlood, 1973; Berkhoudt,1976; Gentle and Breward,1986; Piersma et al,1998; Lunam,2005; Cunningham et al,2007, 2010). In accordance with reports from other seed‐eating passerine species, chickadees do not display features of a bill tip organ (Ziswiler and Trnka,1972; Krulis,1978).…”

“…The infrequent occurrence of Grandry corpuscles, movement‐sensitive mechanoreceptors (Gottschaldt,1985), in the chickadee beak may be similarly related to the rarity of tactile foraging in this species. Our study was not intended to serve as a comprehensive assessment of mechanoreceptors in the chickadee beak and claw and more detailed future investigation of these structures could be aided by specific techniques, such as the use of a silver stain (Piersma et al,1998; Cunningham et al,2007, 2010).…”

“…For example, both beaks and claws contain mechanoreceptors that perceive sensory information such as vibrations, pressure, and temperature, all of which confer information about foraging substrates and potential prey (Heppleston,1970; Lucas and Stettenheim,1972; Gottschaldt,1985; Gentle and Breward,1986). These structures, which may be densely packed in bony pits near the tip of the beak in what has been described as a bill tip organ, have attracted considerable research interest for wading birds that feed by probing in soft substrates (e.g., Zelená et al,1997; Piersma et al,1998; Cunningham et al,2007, 2010) and other species that use the beak extensively for food manipulation (Ziswiler and Trnka,1972; Krulis,1978 and references therein). Magnetoreceptors located in the beak assist in orientation and migration in a variety of species (Fleissner et al,2007; Falkenberg et al,2010).…”

“…In a seminal publication on beak growth and anatomy, Lüdicke (1933) examined the histological structure of the beak in a taxonomically diverse selection of birds, which was followed by Menzel and Lüdicke's (1974) investigation of several psittacine species. Other research on free‐ranging species, including shorebirds (Scolopaci and families within Charadrii), waterfowl (Anatidae), and finches (Fringillidae) has typically focused on the identification of specific sensory structures and their importance in detecting, procuring, and manipulating food items (Krogis,1931; Ziswiler and Trnka,1972; Gottschaldt,1974; Berkhoudt,1976; Krulis,1978; Piersma et al,1998; Cunningham et al,2007, 2010). Several recent publications have also described notably unusual or exotic beaks and accessories (Homberger,2001; Seki et al,2005, 2006, 2010; Chen et al,2008; Tattersall et al,2009).…”

Wild urban companions: living with everyday native animals in Brisbane

“…The Australian white ibis belongs to the avian family Threshkiornithidae, a family which sensory tissues that allow them to feel for invertebrate food such as yabbies, worms, and insect larvae, unseen beneath the surface (Cunningham et al 2010). Not confined to the aquatic realm, they can readily move into areas adjacent to saturated zones, such as riparian grasslands and paddocks, where they use their beaks to jab and peck at grasshoppers and other insects.…”