Biogéographie et Ecologie des Vertébrés

Charlotte ROEMER

Charlotte.ROEMERCharlotte Roemer



Tel : 06 26 09 91 97

Cette adresse e-mail est protégée contre les robots spammeurs. Vous devez activer le JavaScript pour la visualiser.



PhD Project (2015-2018)

Ecologie du mouvement à l’échelle locale chez les chiroptères et risques anthropiques de collision

Bat movement ecology at the local scale and anthropogenic collision risks

Funded by Biotope and the ANRT

Supervisors: Aurélie Coulon (MNHN, CEFE Montpellier), Yves Bas (MNHN) & Thierry Disca (Biotope)


Bats use echolocation to operate during darkness, avoid obstacles and forage. Different species have different types of sonars, depending on the habitats they use. Aerial-hawkers use low quasi-constant frequencies which allow them to fly at heights, whereas gleaners use high-pitched modulated frequencies, better suited to fly close to the ground. Knowledge in bat movement has mainly been developed at large scales for the study of migration routes or at middle scales for the study of home ranges. Little is known about bat behaviour at a very small scale, where obstacle avoidance can be observed.

All European bats are under strict protection (Habitat Directive). It is therefore mandatory for project developers to assess and quantify the impact of their project on those species. Today, the lack of information in bat behaviour at a small scale is problematic when it comes to assessing anthropogenic collision risks with vehicles or wind turbines before construction.

It is commonly assumed that aerial hawkers are less prone to road collisions – but more susceptible to wind turbine collisions – because they prefer to fly at heights. However, mortality rates can greatly vary between study sites. Many assumptions are also formulated concerning the reaction of each species to landscape features and hence the role of these features in mortality. Gleaners are described as flying close to the ground and close to the vegetation whereas aerial-hawkers are supposedly more plastic. However, these elements rely mainly on bat experts’ experience and this flaw leads to hazardous impact assessment studies.

The aim of my PhD is to determine how several types of landscape features alter collision risks with vehicles and wind turbines. Behavioural observations will be performed with acoustic flight path tracking over road localisations or at wind masts. Eventually, the goal is to achieve two prediction models for collision risks – at road or at wind turbine projects – based on local landscape characteristics.


bat, behaviour, ecology, road collisions, landscape, prediction model, impact assessment studies.

Research experiences:

2013 – 2014 – Apprenticeship (1 year) at Biotope (Mèze, France). Research & Development in bat acoustic flight path tracking, field surveys and acoustic analyses for impact assessment studies.  Supervisors: Dr. Yves Bas & Alexandre Haquart.

2013 - Internship (2 months) at Biotope (Mèze, France). Research & Development in bat acoustic flight path tracking.  Supervisor: Dr. Yves Bas.

2011 - Master Thesis (6 months) at ECOMERS - FRE 3729 (CNRS Nice, France). Comparative behavioural study of the effect of temperature on two fish species: effect of climate changes on the vertical distribution of Gobius vittatus and Parablennius rouxi. Supervisor: Prof. Patrice Francour.

2009 - Internship (2 months) at Biotop (Valbonne, France). Research & Development in Trichogramma, parasitoids of the European corn borer.  Supervisor: Julien Séguret.

Voluntary work:

Since 2012 –  Bat inventories (Groupe Chiroptères de Provence, Groupe Chiroptères Languedoc-Roussillon, CEN PACA, Parc National du Mercantour)

International courses:

2011 – Course on tropical bats and research project (2 weeks) at La Selva biological station (Costa Rica). Study on distress calls acoustic parameters in 15 bat species. Professors and supervisors: Dr. Marc Holderied, Dr. Christian Voigt & Prof. Constance Scharff.

2010 – Course on the biology of desert-dwelling bats and research project (2 weeks) at Jacob Blaustein Institutes for Desert Research (Israel). Study on the attraction effect of distress calls in Pipistrellus kuhlii. Professors and supervisors: Dr. Marc Holderied, Dr. Christian Voigt, Dr. Carmi Korine & Prof. Berry Pinshow.


Roemer C., Disca T. & Bas Y. (2016) Corrélation entre nombre de cadavres récoltés en France et proportion de temps passé en altitude. [Talk]. 16èmes Rencontres nationales chauves-souris de la SFEPM (Bourges, France).

Roemer C. & Connes D. (2015) Acoustical flight path tracking for bat conservation: assessment of road collision risks before construction, and mitigation measures propositions. [Talk]. 4th International Berlin Bat Meeting (Berlin, Germany).

Roemer C., Bas Y. & Devos S. (2014) Assessment of bat mortality risks around human activities using unattended recordings for flight path reconstruction, an affordable method for bat behavioural and conservation studies. [Talk]. 13th European Bat Research Symposium (Sibenik, Croatia).

Roemer C., Desbas J.-B. & Bas Y. (2014).  Modelling bat mortality risk on a railway using acoustic flight path reconstruction. [Talk]. 10th Ecology & Behaviour (Montpellier, France).

Roemer C., Desbas J.-B. & Bas Y. (2014).  Modélisation du risque de mortalité des chiroptères sur une voie de chemin de fer par trajectographie acoustique. [Talk]. 15èmes Rencontres nationales chauves-souris de la SFEPM (Bourges, France).

Main disciplines / approaches / study systems: