Alpine Parnassius Butterfly Dispersal: Effects of Landscape and Population Size

Abstract

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Causes and consequences of animal dispersal strategies: relating individual behaviour to spatial dynamics

“…This has been reported in populations of the Glanville fritillary Melitaea cinxia (Kuussaari, Nieminen & Hanski, 1996) and the alpine butterfly, Parnassius smintheus (Roland, Keyghobadi & Fownes, 2000). When the benefits of living in a group exceed the costs of competition, a negative density-dependent emigration may be adaptive, where such benefits include diluted predation risk or foraging facilitation.…”

Connectivity rescues genetic diversity after a demographic bottleneck in a butterfly population network

“…Mark-recapture studies of P. smintheus have been conducted in the population network since 1995 and are described extensively elsewhere (12,13). Adults are individually marked, and spatial locations of captures and recaptures are recorded.…”

“…A network of populations of the Rocky Mountain Apollo butterfly, Parnassius smintheus, occupying patches of alpine meadow habitat in Alberta, Canada, has been monitored and studied continuously since 1995, and effects of both landscape structure and climate variation on population dynamics and dispersal have been described (12,13) (Fig. 1).…”

Isolated trees with high crown coverage and densities increase pasture seed rain

“…Forest fragmentation and habitat loss, especially due to pasture establishment (Fahrig 2003;Fearnside 2005), results in the isolation of plant and animal populations by reducing forest habitats and promoting fragment isolation (Forman & Godron 1986, Damschen et al 2008. Additionally, the isolation of populations in forest fragments creates diffi culties for the movement of pollination and dispersal agents (Tischendorf & Fahrig 2001), restricting functional landscape connectivity (Roland et al 2000;Ricketts 2001;Baum et al 2004) and seed dispersal (Laurance et al 2002).…”