El febrer de 1996 es va observar una fotja a l'embassament de Vrbje (vall de la Baixa Savinja, Eslovènia) menjant excrements d'aus aquàtiques, probablement de cigne mut o oques. Aquest comportament alimentari inusual podria estar relacionat amb la duresa de l'hivern i la dificultat de trobar menjar que els ocells haurien tingut durant aquest any en aquesta zona

Vogrin, Milan

Revistes Catalanes amb Accés Obert

Butll. GCA 14: 63-64.1997 
I A Coot Fulica atra eating waterfowl droppings 
M. VOGRIN 
In February 1996 a Coot Fulica atra was observed on Vrbje pond 
(lower Savinja Valley, Slovenia) feeding on waterfowl droppings, 
probably of Mute Swans Cygnus olor or geese Anser sp. This 
unusual feeding behaviour rnay have occurred because of the hard 
winter and the difficulty in finding food that the birds rnay have 
experienced in that year and in that urea. 
Key words: Coot, Fulica atra, waterfowl droppings, feeding, 
Slovenia. 
Milan Vogrin. Hotinjska cesta 108, SI-231 2 Orehova vas, Slovenia 
E-mail: milan.vogrin@guest.arnes.si 
Rebut: 12.02.98; Acceptat: 02.04.98 
Vrbje pond is situated in the Lower 
Savinja valley near the Savinja River in 
Central Slovenia. The 13.5 ha pond 
supports emergent (e.g. Typha latifolia, T. 
angustifolis) and floating vegetation 
(Potarnogeton crispus, F? natans, P spicaturn, 
Myriophyllurn spicaturn, Elodea canoden- 
sis). Detailed descriptions of the study areas 
are given elsewhere (Vogrin 1996, Vogrin 
& Vogrin 1997). Vrbje pond has been one 
of the focal areas of the Slovenian wintering 
population of Coots Fulica atra in recent 
years. In winter, it supports un average of 
up to 34.6 Coots/ha feeding on algae and 
floating vegetation (Vogrin 1996, 1997). 
On 3rd February 1996, a Coot was 
observed feeding on waterbird droppings, 
whilst walking on the ice and picking up 
seeds, probably of Potarnogeton sp. After 
feeding on the seeds the Coot moved 
towards the dropping, probably of a Mute 
Swan Cygnus olor or a goose Anser sp. and 
started to pick it up. When the Coot finished 
with this dropping it moved towards another 
one and started to feed on it. From a 
distance of about 30 m, I observed the birds 
through 7x50 binoculars. During this time 
I observed two other Coots that were also 
eating waterfowl droppings. On Vrbje pond 
I have observed waterbirds for the past five 
years but this was the first time that I 
recorded such behaviour. 
The day on which the observations were 
made was a cold day with un average 
daytime temperature of -5°C. About 90% 
of the water surface was completely frozen. 
On this day about 600 aquatic birds were 
foraging on the pond, on un available sur- 
Butll. GCA 14, 1997 
face urea of c. 1.4 ha, which means more 
than 400 birds/ha. 
Coots are omnivorous, feeding mainly 
on submerged macrophytes, but also on 
invertebrates and molluscs (Cramp & 
Simmons 1980, Deli¿ 1991, Glutz von 
Blotzheim et al. 1973). The only previous 
report that I found of a Coot feeding on 
droppings was that of Phillips (1991). It 
seems likely that this phenomenon most 
probably occurs only during hard winters 
and possibly also when access to food is 
difficult. We must also take into account the 
nutritional content of faeces which could 
have similar digestibility and nitrogen 
content to those of grass (see Summers & 
Grieve 1982): 
ACKNOWLEDGEMENTS 
I wish to thank community lalec for 
financial support during research work. 
Comments by an anonymous referee and 
by Dr. J. C. Senar improved the manuscript. 
RESUM 
Fotja Fulica atra menjant excrements 
d'aus aquatiques 
El febrer de 1996 una Fotja Fulica atra 
fou observada a I'embassament de Vrbje 
(vall de la Baixa Savinja, Eslovenia) menjant 
excrements d'aus aquatiques, probablement 
de Cigne Mut Cygnus olor o oques Anser 
sp. Aquest comportament alimentari inusual 
podria estar relacionat amb la duresa de 
I'hivern i la dificultat de trobar menjar que 
els ocells haurien tingut durant aquest any 
en aquesta zona. 
REFERENCES 
CRAMF: S. & SIMMONS, K.E.L. (eds.) 
1980. The Birds of the Western Palearctic. 
Vol. 2. Oxford: Oxford University Press. 
DELIC, A. 1991. The food of Coot 
(Fulica atra, L, 1758) on the fish ponds in 
Middle Croatia. Larus 43: 59-80. (In 
Croatian with English summary). 
GLUTZVON BLOTZHEIM, U.N., BAUER, 
K.M. & BEZZEL, E. 1973. Handbuch der 
Vogel Mitteleuropas. Band 5. Galliformes 
und Gruiformes. Wiesbaden: Akademische 
Verlagsgesselschaft. 
PHILLIPS, H.A. 1991. Eurasian Coot 
Fulica atra eating waterbird faeces. Austra- 
lian Birdwatcher 14: 150. 
SUMMERS, W.R. & GRIEVE, A. 1982. Diet, 
feeding behaviour and food intake of the 
Upland Goose (Chloephaga picta) and Ruddy- 
headed Goose (C. rubidiceps) in the Falkland 
Islands. J. of Applied Ecology 19: 783-804. 
VOGRIN, M. 1996. Birds of Vrbje pond 
in the Lower Savinja valley, and a look ut its 
conservationist complexity. Acrocephalus 1 7: 
7-24. (In Slovenian with English Summary). 
VOGRIN, M. 1997. Wintering of Coot 
Fulica atra and Moorhen Gallinula 
chloropus on Vrbje pond in Lower Savinja 
valley (Slovenia). Riv. Ital. Om. 67: 183- 
188. 
VOGRIN, M. & VOGRIN, N. 1997. 
RibnikVrbje z okolico. pp. 17-46. In: VOVK- 
PETROVSKI, G. (ed.). Ribnik Vrbje zokolico. 
Vodnik: lalec. (In Slovenian with English 
summary). 


A Coot (Fulica atra) eating waterfowl droppings

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