01212nas a2200133   4500008004100000245008600041210006900127260001600196300001200212490000600224520078100230100001901011856004801030       2009                        eng d00aHitchhiking behaviour in the obligatory upstream migration of amphidromous snails0 aHitchhiking behaviour in the obligatory upstream migration of am  c2009 Aug 23  a465-4680 v53 aMigratory animals endure high stress during long-distance travel in order to benefit from spatio-temporally fluctuating resources, including food and shelter or from colonization of unoccupied habitats. Along with some fishes and shrimps, nerite snails in tropical to temperate freshwater systems are examples of amphidromous animals that migrate upstream for growth and reproduction after a marine larval phase. Here I report, to my knowledge, the first example of 'hitchhiking' behaviour in the obligatory migration of animals: the nerite snail Neritina asperulata appears to travel several kilometres as minute juveniles by firmly attaching to the shells of congeneric, subadult snails in streams of Melanesian Islands, presumably to increase the success rate of migration.1 aKano, Yasunori  uhttps://neritopsine.myspecies.info/node/230