Chicks of the great spotted cuckoo may turn brood parasitism into mutualism by producing a foul-smelling secretion that repels predators.
The great spotted cuckoo (Clamator glandarius) is an important brood parasite of carrion crows (Corvus corone corone) in northern Spain. We recently found that, unlike what is commonly known for cuckoo-host interactions, the great spotted cuckoo has no negative impact on average crow fitness in this region. The explanation for this surprising effect is a repulsive secretion that the cuckoo chicks produce when they are harassed and that may protect the brood against predation. Here, we provide details on the chemical composition of the cuckoo secretion, as well as conclusive evidence that the dominating volatile chemicals in the secretion are highly repellent to model species representative of common predators of the crows. These results support the notion that, in this particular system, the production of a repulsive secretion by the cuckoo chicks has turned a normally parasitic interaction into a mutualistic one.
Laboratory of Fundamental and Applied Research in Chemical Ecology (FARCE), Institute of Biology, University of Neuchâtel, Rue Emile-Argand 11, 2000, Neuchâtel, Switzerland.
Gregory
G
Röder
Daniela
D
Canestrari
Diana
D
Bolopo
José M
JM
Marcos
Neil
N
Villard
Vittorio
V
Baglione
Ted C J
TC
Turlings
D000819:Animal Communication; D000818:Animals; D001717:Birds / Q000502:physiology*; D002415:Cats; D046368:Crows / Q000469:parasitology* / Q000502:physiology; D046093:Falconiformes / Q000502:physiology; D020387:Food Chain; D008401:Gas Chromatography-Mass Spectrometry; D007302:Insect Repellents; D052617:Solid Phase Microextraction; D013030:Spain; D013559:Symbiosis; D055549:Volatile Organic Compounds / Q000378:metabolism*
D007302:Insect Repellents; D055549:Volatile Organic Compounds