Biological control with unexpected benefits in Tafilalet

The Tafilalet farm is located in the south of the Atlas Mountains, in the historical cradle of Medjool, situated at the border of the Draa Tafilalet and Oriental regions of Morocco. The region is known for its rich cultural heritage and unique biodiversity, concentrated in the regions’ various natural, as well as artificial, oases. The entire region, but especially these oases, represent an important wintering site for migratory birds [1].

Access to clean water is the key element for practicing agriculture in this region. This is secured through renewable groundwater that is continuously recharged with precipitation as well as snow melt from the Atlas Mountains. The Tafilalet farm has constructed two water basins that distribute water throughout the farm. While essential for irrigation, these open water basins are prone to algae blooms that can block filter systems and significantly reduce water quality. Conventional farming approaches would dictate controlling this problem with the application of chemicals. Tafilalet, however, chose an alternative biological control method: the introduction of cyprinid fishes, known in the region as carpe chinoise. The fish feed on the algae and thereby keep their population in check. In June 2020, an initial 2,000 fish were introduced and have flourished - coexisting happily in symbiosis with the algae in the water basins.

The introduction of the fish has moreover brought an unexpected side benefit to the farm. As the fish repopulate, they attract local birds all year-round and migratory birds during winter season, which feed on the fish and use the farm as a resting place and feeding station. Prominent representatives of migratory birds like sparrows as well as two endangered waterbird species, Tadorna ferruginea and Marmaronetta angustirostris, have been spotted on the farm.

To accelerate the desired effects on the local biodiversity and make the farm a more desirable location for local biodiversity, 8,000 additional fish are expected to be introduced in the coming years.

[1] Ramsar (2005): Oasis du Tafilalet. Available at: https://rsis.ramsar.org/ris/1483


This article is an extract of the 2023 12Tree Sustainability Update Report. Download the report to learn more about our progress and key impact areas.