CONTEXT : Wetlands are highly dynamic and productive ecosystems of high socioeconomical values due to ecosystemic services they provide. Yet wetlands are threathened by increasing human activities and climatic change. Restoration of these hydrosystems typically occurs on small scales, both in time and space. Thus, the relevance and the efficiency of such conservation actions are difficult to assess. The European program « Restoring Rhine wetlands and preserving the biodiversity in the vicinity of the Lauter River », initiated in 2009 by the local council (CD67), has re-created trans-bordering water connectivity between France and Germany in order to enhance the establishment and/or the reinforcement of emblematic species of Rhine wetlands, such as the European pond turtle Emys orbicularis. Beyond its emblematic value, this small-sized freshwater turtle fills an original ecological niche: Emys is widely distributed throughout Europe, it is an opportunistic consumer feeding from scavenging to predation (mostly on aquatic macro-invertebrates), and as an ectotherm, it is directly impacted by ambient temperature (and thus by climate change) to thermoregulate (e.g. though sun-basking events). Since 2011, our laboratories IPHC & LIVE cooperate to assess (1) the efficiency of habitat restoration on local biodiversity and (2) the functional contribution of Emys on ecosystem functioning, in order to (3) provide a scientific-based frame for sustainable management of landscapes and wildlife.
OBJECTIVES/HYPOTHESES : We will investigate the ecophysiology of Emys from different populations facing contrasted environmental and climatic conditions throughout its pan-European distribution. We will test the following two hypotheses :_H1_ Due to its physiology, Emys is supposed to adjust its thermoregulatory behaviour throughout a latitudinal gradient over its natural distribution. Using an eco-physiological approach developped at IPHC, based on animal-borne micro-electronics in the wild, IR thermography and respirometry in controlled conditions, we will study seasonal time-budgets and thermal/energetic balances of individuals living under favourable (Aquitaine, PACA), average (Alsace) et extrem (Latvia) climatic conditions. _H2_ Due to its opportunistic behaviour, Emys’ diet is supposed to show seasonality related to the phenology of its main prey species. Using an ecological approach developped at LIVE, the candidate will implement a seasonal monitoring of biological diversity and biomass of aquatic macro-invertebrates in natural and restored ponds, in order to define new indexes of ponds’ quality, food resources availability and quality for Emys, and ultimately indexes of efficiency of restoration actions devoted to Emys. These results will be merged with data on Emys’ individual diet and growth to estimate the predatory pressure of Emys on natural resources, but also the effects of habitat quality on individual health.
In fine, this study aims at identifying the environmental and individual determinants of survival in Emys, and Emys functional ecology in contrasted ecosystems so that we may predict future population dynamics in the context of global change. Expected results will be shared with similar conservation programmes currently led in France (Emys-Actions National Plan) and Europe.
All proposed approaches have already been validated by our teams and have provided a first dataset that can be considered as the reference baseline. This new project benefits recurrent fundings from CD67 and CNRS through the label of Site d’Etude en Ecologie Globale.
KEY WORDS : climate, hydrosystems, ecophysiology, monitoring, vertebrates, conservation, sustainable management
SKILLS REQUIRED : Real knowledge in ecology, animal physiology and behaviour, individual and population biology ; entomology and herpetology ; basic knowledge in signal analysis (MatLab) ; reak skills in data analysis and statistics (ANOVA, GLMM, PCA, non parametric stats) and mastering in stat softwares ; mastering English (reading, writing, speaking) ; a personal experience in the field is welcome, with capacities in performing field protocols, by yourself and within a team.
ACHIEVED COMPEENCES : Ecology : hydrosystems monitoring (abiotic and biological quality, macro-invertebrates taxonomy) ; animal population monitoring (zootechny, biometry, demography) ; foodweb modelling. Ecophysiology : Wildlife behavioural monitoring (animal-borne electronics, tracking) ; animal physiology (plasmatic biochemistry, IR thermography, respirometry). General Skills: project management, time management ; database management, data analysis, scientific publication ; consolidating an international network, grant application.
The subject has been proposed for the forthcoming application 2017 at the Doctoral School 414 of the Université de Strasbourg.
Candidates can contact JYGeorges, by email, with updated cv and motivation letter.
Jean-Yves Georges, [email protected], 0388106950
Institut Pluridisciplinaire Hubert Curien, IPHC (Université de Strasbourg, CNRS, UMR7178), Département Ecologie, Physiologie et Ethologie, 23 rue du Loess, Strasbourg.
CITATIONS REFERENCE :
Enstipp MR, Ballorain K, Ciccione S, Narazaki T, Sato K, Georges JY (2016) Energy expenditure of adult green turtles (Chelonia mydas) at their foraging grounds and during oceanic migration. Functional Ecology 30(11) : 1810–1825, doi : 10.1111/1365-2435.12667
Enstipp MR, Ciccione S, Gineste B, Milbergue M, Ballorain K, Ropert-Coudert Y, Kato A, Plot V, Georges JY (2011) Energy expenditure of freely swimming adult green turtles (Chelonia mydas) and its link with body acceleration. Journal of Experimental Biology 214 : 4010-4020, doi:10.1242/jeb.062943
Plot V, Jenkins T, Robin JP, Fossette S, Georges JY (2013) Leatherback turtles are capital breeders: morphometric and physiological evidence from longitudinal monitoring. Physiological and Biochemical Zoology 86(4) : 385-397, doi: 10.1086/671127