Zembra and Zembretta

Zembra and Zembretta National Park protects two uninhabited Mediterranean islands situated in the Bay of Tunis, off the Cap Bon Peninsula in Nabeul Governorate. Zembra, the larger island, covers approximately 370 hectares and rises to 433 metres; Zembretta is a tiny islet of approximately 15 hectares. Together with their surrounding marine zone of approximately 4,000 hectares, the park was Tunisia's first marine park. The islands are designated an Important Bird Area and a Ramsar Wetland, representing the finest example of pristine Mediterranean island ecosystem in Tunisia.

The islands support the largest Audouin's gull colony in Tunisia and one of the most significant in the western Mediterranean. Cory's shearwater, Yelkouan shearwater, and European storm petrel breed in large numbers on the cliffs and rocky shores. Eleonora's falcon breeds and hunts migrating passerines during autumn. The marine zone is exceptionally rich, with posidonia seagrass meadows, rocky reef communities, and intact fish populations including grouper, sea bass, dentex, and octopus. Mediterranean monk seal has been historically recorded. The island's vegetation is completely free of introduced predators such as rats and cats.

The island vegetation is dominated by dense macchia (maquis) of lentisk, rockrose, Olea europaea, and Pistacia lentiscus, representing intact Mediterranean island scrubland in an extremely well-preserved state. The clifftops support specialist maritime flora including sea squill, sea campion, and various succulents. Rocky slopes have interesting assemblages of endemic Mediterranean island plants. The complete absence of herbivores allows natural vegetation succession to proceed undisturbed. The marine zone supports exceptional posidonia seagrass meadows that are among the healthiest remaining in Tunisia.

Zembra is composed of Miocene limestone forming a steeply inclined island with vertical sea cliffs on the northern and western faces and somewhat gentler slopes on the south. The island represents the exposed top of an underwater limestone ridge extending from the Cap Bon Peninsula. The geological structure is part of the Sicilian-Tunisian Platform, a relatively shallow carbonate shelf connecting North Africa to Sicily. The marine environment around the islands is characterised by rocky reefs and sandy bottoms with excellent water clarity.

The islands have a semi-arid Mediterranean insular climate, moderated by the sea. Annual precipitation is approximately 400-500 mm, mainly in winter. Summers are warm to hot (28-30°C) with frequent sea breezes. Winters are mild and rarely cold. The island's position in the Bay of Tunis exposes it to north and northeast winds that can be powerful. The marine climate supports the exceptional vegetation cover despite relatively limited precipitation.

Zembra was known to ancient navigators as Aethalia or Egitarsa. The island may have been used as an observation and signal post by Carthaginian sailors navigating between Carthage and Sicily. Archaeological evidence of ancient habitation has been found on Zembra. The islands were uninhabited during the medieval and Ottoman periods, used only for seasonal fishing. During the French Protectorate, Zembra was used briefly as a prison. The island has been uninhabited since its designation as a protected area.

Zembra and Zembretta were designated as Tunisia's first marine national park in 1977, recognizing the exceptional conservation value of the uninhabited islands and their surrounding waters. The uninhabited status of the islands has allowed their ecosystems to recover from any historical disturbance and to develop without the invasive species introductions that have devastated seabird colonies on many Mediterranean islands. Access to the islands is strictly controlled, with permits required, ensuring minimal disturbance to breeding seabirds.

The islands are primarily a scientific and birdwatching reserve, with restricted public access to protect the breeding seabirds. Permitted visitors can observe seabird colonies and the remarkable island vegetation. The surrounding marine zone offers exceptional snorkelling and scuba diving in exceptionally clear water with rich marine life. The journey by boat from La Goulette or Kelibia provides opportunities to observe shearwaters and dolphins at sea.

Access to the islands requires permits from the Direction Générale des Forêts. Boat trips operate from La Goulette (near Tunis) or Kelibia on Cap Bon. Day visits for birdwatching and snorkelling are permitted for authorised groups. The island has no permanent accommodation or infrastructure. Accommodation is available in Kelibia town on Cap Bon. The best season for seabird observation is May through August when breeding is underway.

The islands' pristine condition is their primary conservation asset. The main threats are marine pollution from shipping traffic in the Bay of Tunis, illegal fishing in the marine protected zone, and disturbance to nesting seabirds by unauthorised boat activity. Climate change and ocean warming may affect posidonia seagrass extent and seabird breeding success. The park cooperates with international ornithological organisations monitoring Audouin's gull and shearwater populations. Strict access control is the cornerstone of the conservation management strategy.