380 likes | 553 Views
Variation in dispersal capacity and behaviour in the Natterjack toad ( Bufo calamita ). Joke Maes Herpetology 22 March 2012. Promotor: Erik Matthysen Co-promotor: Raoul Van Damme. Dispersal. Dispersal. Individual and among-population variation in dispersal capacity
E N D
Variation in dispersal capacity and behaviour in the Natterjack toad (Bufo calamita) Joke Maes Herpetology 22 March 2012 Promotor: Erik Matthysen Co-promotor: Raoul Van Damme
Dispersal Individual and among-population variation in dispersal capacity Selection in favour or against dispersal Local adaptation in dispersal capacity
Dispersal capacity Fragmentation Distance between habitat patches > thorax Hesperia comma (Hill et al. 1999)
Geographical variation in habitat persistence Macroptere/brachyptera Prokelisia marginata (Denno et al. 1996) Dispersal capacity Habitat persistence Turn over rate > proportion of high dispersal genotype Caenorhabditis elegans (Friedenberg 2003)
Dispersal capacity Selection for faster toads with longer legs and better endurance in Cane toad (Bufo marinus) (Phillips et al. 2006; Llewelyn et al. 2010) Bufo marinus
Natterjack toad (Bufo calamita) • Protected Endemic European species • Mobile • Pioneer species • Temporary ponds • High extinction risk Connectivity through dispersal
Natterjack toad (Bufo calamita) → Dispersal by juveniles (up to 2 km: Sinsch 1997)
Research question Local adaptation in dispersal capacity in the Natterjack toad?
Material & methods Dispersal-related traits in frogs and toads • Snout-vent length • Relative leg length • Body condition • Endurance • Sprint speed
Material & methods 2008: eggs raised in a common environment (CE) 2009: metamorphosed toadlets collected in their natural environment (NE)
Natterjack toad Kalmthout ML1 Tielrode SH1 Den Diel SH2 Kikbeekbron ML2 LO MD1 Liereman SL1
Material & methods Snout-vent length Relative leg length Body condition Endurance Sprint speed 83 cm
Dispersal behaviour Lab studies on animal behaviour : shy/boldness, social behaviour, explorative behaviour, activity, aggression, … Repeatability Behavioural correlations ‘Behavioural syndrome’(‘Personality’, ‘Temperament’) Gambusia affinis (Cote et al. 2010) Dispersal propensity Parus major (Dingemanse et al. 2003) Lacerta vivipara (Aragon et al. 2006)
Dispersal behaviour Lab studies on animal behaviour : shy/boldness, social behaviour, explorative behaviour, activity, aggression, … Repeatability Behavioural correlations ‘Behavioural syndrome’(‘Personality’, ‘Temperament’) Gambusia affinis (Cote et al. 2010) Dispersal propensity Parus major (Dingemanse et al. 2003) Lacerta vivipara (Aragon et al. 2006) Local adaptation in behavioural syndromes?
Dispersal behaviour Do natterjack toads have personality? ‘Bold’ ‘Shy’ ‘Behavioural syndrome’ in the Natterjack toad?
Research question Local adaptation in dispersal capacity? Behavioural syndrome in the Natterjack toad? Behavioural syndrome linked to dispersal tendency? Local adaptation in behaviour? • Repeatability? • Correlation?
Material & methods Behavioural variables ‘Open field test’ (lab)
Material & methods • Shyness: latency • Locomotor activity (Percentage of time active after the first movement) • Explorative tendency (surface explored • after the first movement) • Corridor use • Maximum speed • Average speed • > Repeated after six weeks and after one year
Material & methods ‘Release patch’ ‘Corridor’ Behavioural variables Dispersal tendency ‘Open field test’ (lab)
Material & methods ‘Release patch’ ‘Corridor’ Behavioural variables Dispersal tendency Outdoor ‘Open field test’ (lab)
Results Behavioural syndrome in toads? Repeatability dispersal behaviour Vbetween/(Vbetween + Vwithin) After statistical correction for morphometry • Repeatability > individual variation ecological relevant
Results Behavioural syndrome in toads? Repeatability dispersal behaviour Vbetween/(Vbetween + Vwithin) After statistical correction for morphometry CE NE • Repeatability > individual variation ecological relevant • Repeatability NE bigger than CE
Results Behavioural syndrome in toads? Behavioural correlations?
Results Behavioural syndrome in toads? CE NE
Results Behavioural syndrome in toads?
Results Behavioural syndrome in toads? No correlations between behaviour and capacity parameters
Results Behavioural variables: • Repeatable? • Correlation? • Correlations with dispersal tendency? Behavioural syndrome possibly linked to dispersal
Results • Correlations between behavioural variables (2009) and dispersal • tendency (2010)? • Toadlets that reached the end of the corridor in the open field test had • a higher dispersal tendency in the outdoor experiment (p = 0.034) • Time to reach the end of the outdoor corridor correlated with • personality traits. Correlation r = - 0.22 P = 0.035
Results • Correlations between behavioural variables (2009) and dispersal • tendency (2010)? • Toadlets that reached the end of the corridor in the ourdoor experiment, were more social.
Results Local adaptation in dispersal capacity and/or behaviour? Dispersal capacity • Snout-vent length, relative leg length and body condition
Results Local adaptation in dispersal capacity and/or behaviour? Dispersal capacity • Snout-vent length, relative leg length and body condition • Endurance and sprint speed
Results Local adaptation in dispersal capacity and/or behaviour? Dispersal capacity • Snout-vent length, relative leg length and body condition • Endurance and sprint speed ? ?
Results Local adaptation in dispersal capacity and/or behaviour? Dispersal capacity • Snout-vent length, relative leg length and body condition • Endurance and sprint speed ? ?
Results Local adaptation in dispersal capacity and/or behaviour? Dispersal capacity • Snout-vent length, relative leg length and body condition • Endurance and sprint speed Dispersal behaviour
Conclusion ‘Bold’ ‘Shy’ • Personality in terms of individual variation in behaviour • Among-population variation in dispersal capacity • No indications on local adaptation in behavioural syndrome