Unusual predations by a Tawny Owl Strix aluco couple in Northern Italy
The WWF Refuge Le Foppe lies in the Po Plane (Lombardy, Northern Italy), nearly 25 kms
to the east of Milan. It is a small (5.5 ha) and level protected area,
characterized by the occurrence of important species. The word "Foppe"
(local dialect) means "holes". Several ponds (the "Foppe") are the most
typical character of the reserve, they used to be holes, whose origin is
related to the past quarrying of clay.
The area has been subjected to a process which transformed it in a natural environment. A wood
characterized by the presence of ponds has grown. The
Tawny Owl Strix aluco
is the prevailing predator.
Our group have been carrying out a study on the status, the ecology and the ethology
of this raptor in the area for two years. Six birdhouses have been placed in
the wood. One of them has been used by a breeding couple in 2000 and in
2001.
Work around the nest of Tawny Owl in the Foppe's reserve
Photo by Stefano Benini
The study on the Tawny Owl diet often gives interesting and curious details: Mikkola (1983) reported the
occurrence of diurnal and nocturnal raptors among the preys of this species
in the Palearctic: Goshawk Accipiter gentilis, Sparrowhawk
Accipiter nisus, Hobby Falco subbuteo, Kestrel
Falco tinnunculus, Merlin Falco colombarius, Long-eared Owl
Asio otus, Barn Owl Tyto alba, Little Owl Athene noctua,
Scops Owl Otus scops, Pygmy Owl Glaucidium passerinum,
Tengmalm's Owl Aegolius funereus.
In a recent review of the Tawny Owl diet in the Palearctic area, P. Galeotti (2001) has pointed out and
stressed a strong occurrence of birds.
Among the non-passerine species of larger size, the literature reported the predation of an adult of Mallard
Anas platyrinchos (Schnurre, 1934). In Italy the following ones have
been described: Quail Coturnix coturnix and Little Owl Athene
noctua (A.Manganaro et al., 1990), Nightjar Caprimulgus
europaeus (Fraticelli, 1983), Hoopoe Upupa epops (Sarà & Zanca,
1989) and Kestrel Falco tinnunculus (Sarà & Zanca, 1989). The Great
Spotterd Woodpecker Picoides major is more frequentely present in the
diet of this nocturnal raptor (A.Manganaro et al., 1990; A.Manganaro
et al. 1997; De Bernardi & Patriarca, 1988).
Some studies show that the Tawny Owl diet includes a higher percentage of birds in urban and sub-urban
areas, especially where parks and wooded portions occur (Galeotti, 2001;
Galeotti et al., 1991). In built-up areas, strongly anthropophile
species are present among the prey of this raptor: Collared Dove
Streptopelia decaocto, Rock Dove Columba livia, Swift Apus
apus (Galeotti et al., 1991; Ranazzi L. et al.,
2000). These birds are characterized by a high biomass.
During the two breeding seasons studied, the birdhouse was examined and two predations never recorded in
Italy have been discovered: a Moorhen (a claw was found in the nest box) and
a Grey Partridge Perdix perdix (several plumes turned out to be in
the nest box). Both birds were adult. The occurrence of the latter is to be
related to introductions for hunting purpose. The predation occurred in the
fields near the reserve and was probably favoured by the lack of experience
of a bird not used to living in natural environments.
Leg of Gallinula chloropus (Moorhen) into the nest of Strix aluco
The Moorhen is the commonest water bird in the reserve and it is likely to have been predated near the
Tawny Owl nest, where ponds frequented by Moorhens occur.
Further studies will be carried out and we hope to define better the diet of the Tawny Owl in this area.
We would thank for their help during our study: Alessandro Villa, Stefano Benini, Claudio Crespi,
and Alberto Confalonieri.
References:
De
Bernardi P., Patriarca E., 1988. Dati preliminari sulla predazione
dell'Allocco Strix aluco nel Parco regionale La Mandria
(Torino,Piemonte). Riv. Piem. St.Nat. 9:189-196
Fraticelli F., 1983. Un caso di ornitofagia nell'Allocco Strix aluco.
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Galeotti P., 2001. Tawny
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Galeotti P., Morimando F., Violani C., 1991.
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Sarà M.,Zanca L., 1989. Regime alimentare dell'Allocco Strix aluco in
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