Bats of Bou Hedma National Park: Habitat use and conservation, 2010-2011

This project was conducted by Société Française pour l'Etude et la Protection des Mammifères (SFEPM) between April 2010 and November 2011, and was funded by German Federal Ministry for the Environment, Nature Conservation and Nuclear Safety.

The Bou Hedma national park is a typical pseudo savanna of North Africa, with the only forest of Acacia tortilis raddiana in Tunisia. According to the bibliography, 8 species have been recorded in the area: Rhinopoma hardwickii, Rhinolophus mehelyi, Tadarida teniotis, Miniopterus schreibersii, Eptesicus serotinus, Pipistrellus kuhlii, Plecotus teneriffae and Myotis punicus (COPA-DGF 2005).

The objectives of this study were to:

-        record bat species living in the park (contribution to the biodiversity inventory),

-        survey monthly bat activity in the different habitats for improving the most suitable foraging areas,

-        study the diet of some species for identifying relevant preys for conservation,

-        locate the main roosts used by bats along the year in order to enforce their protection.

In order to fulfill part of these objectives the activity of bats has been recorded monthly in the main habitats of the park for :more than an annual cycle. Due to field constraints, six foraging sites were selected in the plain of the integral protection zone 1 of this park: Bou Hedma’s Bordj, Bou Hedma’s valley, Spring of Nouh, House of Brik, Acacia (Acacia raddiana) area, Pistachio (Pistacia atlantica) wood. Each field session started 15 min after sunset and lasted during 3 hours. Two techniques have been used:

a - Mistnetting. Bats were trapped using a mistnet (2.5 m * 12 m, 16 mm * 16 mm). All the captured specimens were identified by using the guides of Dietz (2005), Dietz et al. (2007) and Aulagnier et al (2008), and measured. The first ten individuals of each species were placed in polyester bags in the presence of an insecticide to collect droppings and ectoparasites. Identifications will be conducted thereafter. Seven species were captured: Eptesicus isabellinus, Pipistrellus kuhlii, Miniopterus schreibersii, Plecotus gaisleri, Myotis punicus, Otonycteris hemprichii and Tadarida teniotis, and the monthly activity was recorded for the two first species.

b - Bat detection. Echolocation calls were detected and recorded temporarily using a bat detector Pettersson D 240x, and stored using a recorder EDIROL R-09RH. These signals were analyzed using the software Bat Sound 3.10 (edition 1996-2000 by Pettersson Elektronik AB). The recording of echolocation calls started only in April 2010 due to some difficulties to import the bat detector.

Until now, it was possible to identify eleven species in the park, including Rhinopoma cystops, Rhinolophus ferrrumequinum and two other rhinolophids. Bats were active during all the year, the basin of Bordj and the basin of Nouh were the main hunting habitats. P. kuhlii and E. isabellinus were again the most abundant species.

 

                   Habitats

Species

Bou Hedma’s Bordj

Bou Hedma’s valley

Spring of Nouh

House of Brik

Acacia

Pistachio

E. isabellinus

+

+

+

+

+

+

P. kuhlii

+

+

+

+

+

+

M. schreibersii

+

+

+

 

+

+

T. teniotis

+

+

+

+

+

+

O. hemprichii

+

+

+

+

+

+

M.  punicus

+

+

+

 

+

+

R. cystops

+

+

+

+

+

+

R. ferrumequinum

 

 

+

 

 

 

Rhinolophus sp1

(FC à ≈ 105 kHz)

+

 

+

 

 

 

Rhinolophus sp2

 (FC à ≈ 112 kHz)

+

 

+

 

 

 

Chiroptera sp1

(QFC à ≈ 23 kHz)

+

+

+

+

+

+

Frequency

10/11

8/11

11/11

6/11

8/11

8/11

 

c - Study of the diet. This part of the study hass been delayed and will start soon thanks to a caollaboration with Karima Brahmi (Université de Tizi-Ouzou).

d- Roost search. The search for bat roosts was carried out in summer and winter times in the different zones of the park. Cracks of the valley cliffs and cracks of the Bou Hedma Hedma mountain were prospected but no roost was recorded. However some likely droppings of Eptesicus isabellinus and Pipistrellus kuhlii were observed, in summer, in a crack located near the spring of Nouh. Outside the park an interesting roost for Rhinolophus euryale has been discovered.

Conclusion. The aim was fully achieved with the training of a native batworker to the main techniques used for studying bats, and particularly to bat detection, thanks to the help in the firld and by mail of several foreign batworkers: Frédéric Leblanc, Dino Scaravelli and Benjamin Allegrini.

II - International collaboration

This project envolved batworkers from two Mediterranean countries of the Eurobats Agreement:

- Dino Scaravelli (Italy), who visited the park and teached me the mistnetting and abt handling techniques,

- Frédéric Leblanc (France), who teached me the recording and analysis of echolocation calls during a two-weeks period in France and a visit in Bou Hedma National Park,

- Benjamin Allegrini (France), who analysed some difficult echolocation calls,

- Karima Brahmi (Algeria), who will teach me the techniques for studying the diet of bats from faeces analyses.

III - Scientific production

One paper, a synthesis on present knowledge on Tunisian bats, was completed and published during the period study (Dalhoumi et al. 2011) and one poster presented the first results of an annual mistnetting monitoring in a franco-tunisian congress of mammalogy.

Dalhoumi R., Aissa P. & Aulagnier S., 2011. Taxonomie et répartition des Chiroptères de Tunisie. Rev. suisse Zool., 118(2) : 265-292.

Dalhoumi R., Aulagnier S. & Aissa P., 2010. Ecologie des Chiroptères du parc national de Bou-Hedma. 2ème Congrès franco-maghrébin de Zoologie & 4èmes Journées franco-tunisiennes de Zoologie, Zarzis (Tunisie) 4-11.11.10.

IV - Conservation issues

The scheduled management plan and booklet will be prepared later, after the end of the field study and subsequent analyses. However a first conservation issue is linked to the discovery of the roost of a colony of Mediterranean horseshoe bat. The annual monitoring of the cave evidenced some major disturbance by local young people. With the help of a new local conservation NGO, the entrance of the cave will be fenced in order to protect the colony. Some extra-funding is needed to buy furnitures.

V - Public awareness

A leaflet was produced during the year 2010. Due to political issues it is still not printed and some extra-funding is requested for this purpose.