Black Swan and Western Tiger Snake; a conflict avoidance encounter.
Australina Bird Study Association
Computing, Health and Science
Snakes are known to be predators of bird nests (Skutch 1966; Thompson et al. 1999) and adult birds (Rodda 1997; Stake 2001), with adults sometimes killed during nest defense (King I999). Birds may respond in different ways to different snakes. Quinn (1985), reported that colonial nesting Caspian Terns Sterna caspia hovered two metres over a venomous rattlesnake to avoid contact and Blem (1979) described group mobbing of non-venomous rat Snakes by colonial nesting Bank Swallows Riparia riparia. Tiger snakes Notechis spp., are responsible for a significant proportion of snake-bite deaths recorded in Australia (Cogger 1996). They have a reputation for aggressiveness, Although this may be a misinterpretation of their defensive posture. They may sometimes stand their ground with forebody raised and neck flattened but this is considered a defensive behavior, an intimidation or bluff. They are unlikely to bite unless touched (Bush er n1, 1995). Most recorded human snake-bite deaths are the result of contact. Generally from accidentally stepping on them. The Western Tiger Snake has been documented a s a significant predator of the chicks of Silver Gulls Larus novaehollandiae on Carnac Island, near Perth (Bonnett et al. 1999; Bonnett et al. 2002) and dead adults have also been detected at nests on the island (D. Pearson and M. Ladyman, pers. comm.).