SOCIAL INTERACTIONS IN TWO SYMPATRIC SALAMANDERS: EFFECTIVENESS OF A HIGHLY AGGRESSIVE STRATEGY

摘要: In terrestrial plethodontid salamanders, aggressive behaviour is thought to function in the spacing of territorial residents among contested cover objects on forest floor. Such behaviour, when exhibited toward heterospecifics, plays an important role competitive interactions between species. We compared levels intra- and interspecific contexts two species sympatric salamanders (Plethodon ouachitae P. albagula) that have similar ecological requirements but differ adult size. also tested effectiveness such holding (territorial foci) laboratory predicted if one were more than other, then would greater success obtaining objects. trials, (the smaller species) extremely both contexts. Individuals P delivered bites at a rate 14 times previously studied Plethodon significantly likely escalate biting as (in trials) intruders trials). albagula lower level aggression, other Plethodon. which competed for differing quality, effective expelling conspecific intruders, they marginally intruding albagula. Residents less did not expel ouachitae. conclude extreme aggression by enabled it from artificial invade held larger heterospecific residents. Field data supported intraspecific defence ouachitae, results inconclusive. These are consistent with geographic distributions these (P. typically outnumbers Ouachita Mountains) provide example behavioural mechanism overcoming size-related disadvantage.