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Long-termsiteoccupancymonitoringoftheyellow-belliedtoad
(Bombinavariegata)inAlsace(France).Resultsofthethreefirstsessions.
Jean-Pierre Vacher1, Hugo Cayuela, Julie Reynaud, Julie Lambrey
1BUFO, 8 rue Adèle Riton, 67000 Strasbourg. [email protected]
Bern,2.12.2107
Introduc@on
International
• Loss of biodiversity
• Amphibian decline
National and regional
• Integration in the Natura 2000 network
• Integration in conservation schemes: green corridors, “ZNIEFF”…
Introduc2on Materials&Methods Results Discussion
VUVulnerable
LCLeast
Concern
Introduc@on
Introduc2on Materials&Methods Results Discussion
Introduc@on
Introduc2on Materials&Methods Results Discussion
©JPVacher
NTNearlythreatened
Introduc@on
Introduc2on Materials&Methods Results Discussion
Questions
• What is the population trend of the yellow-bellied toad in Alsace?
• What are the variables that influence detection and occupancy?
• 3 natural regions
• 150 plots
• Random selection of 4 subplots (n=600)
• Binary response (0/1)
• Biennial
Introduc2on Material&Methods Results Discussion
Sampledesign:Siteoccupancy
300m
300m
Introduc2on Material&Methods Results Discussion
Sampledesign:Siteoccupancy
Introduc2on Material&Methods Results Discussion
Occupancyanddetec@on
• Occupancy (each year and between years)
• Detection probability (each year and between years)
• Extinction rate (between years)
• Colonization rate (between years)
Package unmarked in R
2013 2015 2017 2019 …t
Introduc2on Material&Methods Results Discussion
Detec@onvariables
Cayuelaetal.2015(Pop.Ecol.)
Introduc2on Material&Methods Results Discussion
©JPVacher
©JPVacher
©JPVacher
• Air temperature
• Number of water collections per subplot
Detec@onvariables(fieldwork)
Occupancyvariables(GIS)
Introduc2on Material&Methods Results Discussion
• Agricultural area (sampling plot + 1500m buffer)
• Path density (sampling plot)
• Habitat fragmentation (1500 buffer)
1500m buffer Sampling plot
Occupancyvariables(GIS)
Introduc2on Material&Methods Results Discussion
Softwares: GIS (R or QGIS) + FRAGSTATS
Results:monitoring
Introduc2on Materials&Methods Results Discussion
Results:GISanalysis
Introduc2on Materials&Methods Results Discussion
Occurrence Extinction
Sampling plot
Introduc2on Materials&Methods Results Discussion
Results:GISanalysis
1500m buffer
Occurrence Extinction
Discussion
Introduc2on Materials&Methods Results Discussion
2015 2017
Nochangeinlandusebetweenyears
Discussion
Introduc2on Materials&Methods Results Discussion
20
30
40
50
60
70
80
90
Mean precipitations in Alsace - 2017
Month
Me
an
(m
m)
Jan.
Feb.
Mar.
Apr.
May
Jun.
Jul.
Aug.
Sep.
Oct.
Nov.
Dec.
Alsace 2017
Seasonal norms
Discussion
Introduc2on Materials&Methods Results Discussion
©JPVacher
2015 2017
Droughtin2017
Perspec@ves
Introduc2on Materials&Methods Results Discussion
Distribu2onofBombinavariegata
2000-2015
Perspec@ves
Introduc2on Materials&Methods Results Discussion
Adjustments to the protocol
• How many plots?
• Where to place the plots?
• Who will do the analyses?
Acknowledgements
For their help on the field in 2017:
• Sarah Baouch (BUFO)
• Aurélie Berna (BUFO)
• Léa Merckling (RNN Petite Camargue Alsacienne)
For providing permits to access the forests
• Office national des forêts
ThankyouforyouraNen@on!