1 Tr - Chioglossa

COMPORTAMENTO FRUxíVORO DO TORDO REAL 85
TÁBÜA 3. Estatísticos descriptivos da taxa de intentos e da eficacia de dispersión. A diferencia entre especies foi
significativa nos dous casos (taxa de intentos: D M1 =0,53, p < 0,001; eficacia de dispersión: D M1 =0,33, p < 0,05).
[Descriptive statisticsfor attempt rate and dispersa/ efficiency. The differences between the species were statistical/y
significant in both cases.]
S. aucuparia C. monogyna
Media n D.!. Media n D.!.
Mean S. d. Mean S. d.
Taxa de intentos (Attempt rate) 3,70 29 2,72 10,93 32 7,45
Eficacia de dispersión (Dispersal efficiency) 0.87 30 0,17 0,95 33 0,11
SUMMARY
Fruit-eating behaviour of Fie/dfare (Turdus pilaris):
differences between two p/ant species
1 compared the behaviour of fieldfares (Turdus
pi/aris) when eating fruits of two plant species, Crataegus
monog}'lw and Sorbus aucuparia. The two
species differ as regards fruit characteristics and geographical
range. Data were recorded during 63.5 h of
direct observation with the aid of binoculars and
telescope in four sites in Scotland. Sorbus aucuparia
fruits appear to have been more difficult to access,
but were eaten more successfully and more rapidly.
Dispersal efficiency was higher for S. aucuparia
fruits. These results illustrate the strong intluence of
plant characteristics on the behaviour of the animals
that interact with them.
Key words: Crataegus monogyna, feeding ecology,
Fieldfare, frugivory, Hawthorn, Rowantree, Sorbus
aueL/paria, Turdus pi/aris.
BIBLIOGRAFÍA
Debussche, M., Lepart, J. e Molina, J. (1985) La dissémination
des plantes a fruits charnus par les
oiseaux: role de la structure de la végétation et
impact sur la succession en région méditerranéenne.
Acta Oecol. Oeco/ Gen., 6: 65-80.
Foster, M. S. (1987). Feeding methods and efficiencies
of selected frugivorous birds. The Condor,
89: 566-580.
Godschalk, S. K. B. (1985) Feeding behaviour of
avian dispersers of mistletoe fruit in the Loskop
Dam Nature Reserve, South Africa. S. Afr. 1.
200/.,20(3): 136-146.
Greenberg, R.; Niven, D. K.; Hopp, S. e Boone, C.
(1993). Frugivory and coexistence in a resident
and a migratory vireo on the Yucatan peninsula.
The Condor, 95: 990-999.
Guitián, J. (1989). Consumo de frutos de acebo (l/ex
aquifo/ium L.) y movilización de semillas por passeriformes
en las montañas cantábricas occidentales,
noroeste de España. Ardeo/a, 36(1): 73-82.
Herrera, C. M. (1985). Habitat-consumer interactions
in frugivorous birds. En M. L. Cody (Ed.): Habitat
Se/ection in Birds, págs. 341-365. Academic
Press. New York.
Herrera, C. M. (1987) Vertebrate-dispersed plants of
the Iberian Peninsula: a study of fruit characteristics.
Ec%gica/ Monographs, 57(4): 305-331.
Herrera, C. (1995). Plant-vertebrate seed dispersa]
systems in the Mediterranean: ecological, evolutionary,
and historical determinants. AnnL/. Rev.
Eeo/. Syst. 26: 705-727.
Herrera, C. M. e Jordano, P. (1981). Prunus mahaleb
and birds: the high-efficiency seed dispersal system
of attemperate fruiting tree. Ec%gical
Monographs, 51(2): 203-2]8.
Jordano, P. (1992). Fruits and Frugivory. En M. Fenner
(Ed.): Seeds: the ecology of regeneration in
plant communities, págs. 105-152 C.A.B.
lnternational, London.
Levey, D. J.; Moermond, T. C. e Denslow, J. S.
(1984) Fruit choice in neotropical birds: the
effect of distance between fruits on preference
patterns. Ecology, 65(3): 844-850.
McPherson, J. M. (1988). Preferences of cedar wax-