O. Martucci et al., FISH OTOLITHS AS INDICATORS OF THE CORMORANT PHALACROCORAX-CARBO DIET(AVES, PELECANIFORMES), Bollettino di zoologia, 60(4), 1993, pp. 393-396
The form and structure of fish otoliths are species specific. The vali
dity of using ololiths found in pellets to determine the number, size
and weight of fish consumed was tested on cormorants. They were fed wi
th fishes of known number, size and weight; pellets were recovered aft
er 24 hours. Sandsmelt (Atherina boyeri), striped mullet (Mugil cephal
us), sole (solea vulgaris) and eel (Anguilla anguilla) were used. It w
as found that it is possible to estimate the size and weight of prey c
onsumed by birds from size or weight of the otoliths recovered from pe
llets.