Variation in dispersal capacity and behaviour in the Natterjack toad (Bufo calamita)

Joke MaesHerpetology 22 March 2012

Promotor: Erik Matthysen Co-promotor: Raoul Van Damme

Dispersal

Dispersal

Individual and among-population variation in dispersal capacity

Selection in favour or against dispersal

Local adaptation in dispersal capacity

Dispersal capacity

Distance between habitat patches > thorax

Hesperia comma

(Hill et al. 1999)

Fragmentation

Geographical variation in habitat persistence

Macroptere/brachyptera Prokelisia marginata

(Denno et al. 1996)

Dispersal capacityHabitat 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

Connectivity through dispersal

Natterjack toad(Bufo calamita)

Protected Endemic European species

Mobile

Pioneer species

Temporary ponds

High extinction risk

→ Dispersal by juveniles (up to 2 km: Sinsch 1997)

Natterjack toad(Bufo calamita)

Research question

Research question

Local adaptation in dispersal capacity in the Natterjack toad?

Snout-vent length

Relative leg length

Body condition

Endurance

Sprint speed

Dispersal-related traits in frogs and toads

Material & methods

2008: eggs raised in a common environment (CE)2009: metamorphosed toadlets collected in their natural environment (NE)

Material & methods

Kalmthout ML1

Kikbeekbron ML2

Natterjack toad

Liereman SL1 LO MD1

Tielrode SH1

Den Diel SH2

83 cm

Material & methodsSnout-vent length Relative leg lengthBody conditionEnduranceSprint speed

Dispersal behaviour

(Dingemanse et al. 2003)Parus major

Gambusia affinis(Cote et al. 2010)

‘Behavioural syndrome’ (‘Personality’, ‘Temperament’)

Dispersal propensity

RepeatabilityBehavioural correlations

Lab studies on animal behaviour : shy/boldness, social behaviour, explorative behaviour, activity, aggression, …

Lacerta vivipara(Aragon et al. 2006)

Dispersal behaviour

(Dingemanse et al. 2003)Parus major

Gambusia affinis(Cote et al. 2010)

‘Behavioural syndrome’ (‘Personality’, ‘Temperament’)

Dispersal propensity

RepeatabilityBehavioural correlations

Lab studies on animal behaviour : shy/boldness, social behaviour, explorative behaviour, activity, aggression, …

Local adaptation in behavioural syndromes?

Lacerta vivipara(Aragon et al. 2006)

Dispersal behaviour

‘Behavioural syndrome’ in the Natterjack toad?

‘Bold’ ‘Shy’

Do natterjack toads have personality?

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?

‘Open field test’ (lab)

Behavioural variables

Material & methods

Test 64 (0A0114-met geur)Liereman

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Reeks1

Test 16 (0A0100-zonder geur)Liereman

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Test 18 (0A0115-met geur)Oasis

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Test 69 (0A0149-zonder geur)Tielrode

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Test 19 (0A0114-zonder geur)Liereman

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Reeks1

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

‘Open field test’ (lab)

Behavioural variables Dispersal tendency

Material & methods

‘Corridor’‘Release patch’

‘Open field test’ (lab) Outdoor

Behavioural variables Dispersal tendency

Material & methods

‘Corridor’‘Release patch’

Results

Repeatability dispersal behaviour

Repeatability > individual variation ecological relevant

Behavioural syndrome in toads?

After statistical correction for morphometry

Vbetween/(Vbetween + Vwithin)

  Common environment   Natural environment

6 weeks 6 weeks 1 year

           

Latency 0.27 0.47 0.30

Activity 0.28 0.35 0.19

Explorative tendency 0 0.35 0.20

Corridor use 0.24 0.23 0.13-0.08

Maximum speed 0.21 0.47 0.36

Average speed 0.10 0.48 0.30

           

Results

Repeatability dispersal behaviour

Behavioural syndrome in toads?

After statistical correction for morphometry

Vbetween/(Vbetween + Vwithin)

  Common environment   Natural environment

6 weeks 6 weeks 1 year

           

Latency 0.27 0.47 0.30

Activity 0.28 0.35 0.19

Explorative tendency 0 0.35 0.20

Corridor use 0.24 0.23 0.13-0.08

Maximum speed 0.21 0.47 0.36

Average speed 0.10 0.48 0.30

           

Repeatability > individual variation ecological relevant Repeatability NE bigger than CE

NECE

Results

Behavioural correlations?

Behavioural syndrome in toads?

CE NE

ResultsBehavioural syndrome in toads?

ResultsBehavioural syndrome in toads?

ResultsBehavioural 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.

ResultsLocal adaptation in dispersal capacity and/or behaviour?

Dispersal capacitySnout-vent length, relative leg length and body condition

ResultsLocal adaptation in dispersal capacity and/or behaviour?

Dispersal capacitySnout-vent length, relative leg length and body conditionEndurance and sprint speed

ResultsLocal adaptation in dispersal capacity and/or behaviour?

Dispersal capacitySnout-vent length, relative leg length and body conditionEndurance and sprint speed

?

?

ResultsLocal adaptation in dispersal capacity and/or behaviour?

Dispersal capacitySnout-vent length, relative leg length and body conditionEndurance and sprint speed

?

?

ResultsLocal adaptation in dispersal capacity and/or behaviour?

Dispersal capacitySnout-vent length, relative leg length and body conditionEndurance and sprint speed

Dispersal behaviour

Personality in terms of individual variation in behaviour

Among-population variation in dispersal capacity

No indications on local adaptation in behavioural syndrome

Conclusion

‘Bold’ ‘Shy’