CINNAMAMIDE PREVENTS CAPTIVE CHESTNUT-CAPPED BLACKBIRDS (AGELAIUS-RUFICAPILLUS) FROM EATING RICE

Chestnut-capped Blackbirds (Icteridae: Agelaius ruficapillus) are beli eved to cause significant damage to maturing rice grown in reclaimed m arshland bordering the River Parana in north-east Argentina. Efforts t o reduce this damage have involved spraying the birds with avicides, s uch as parathion, and spraying the vegetation in which they breed and roost with herbicides, such as paraquat. This has potentially damaging consequences for local non-target flora and fauna and to the river it self. Non-toxic chemical repellents derived from plant secondary compo unds may provide an alternative means of preventing damage. One such r epellent is cinnamamide. Two choice and 'short-term no choice' tests c arried out with cinnamamide-treated mature rice grains (0.8% (w/w)) sh owed clearly that cinnamamide significantly reduced food consumption b y captive Chestnut-capped Blackbirds. Those birds which sampled the tr eated rice also showed symptoms of distaste, such as head-shaking and gaping, and postingestional malaise.