Very little is known about sharks in Mozambique. Our Scientific Director, Calum Murie, is working to examine the movements, habitat use and feeding ecology of bull (Zambezi), hammerhead, and oceanic blacktip sharks. To date, we are tracking 22 sharks along Inhambane coastline and in the Bazaruto Archipelago National Park. These sharks will continue to transmit data on their movements for up to 10 years. It is our aim to build our knowledge and develop policies that promote their conservation.
Our shark tracking project is the first in southern Mozambique and it will provide the first information on predator sharks in the area. Acoustic telemetry simply refers to using sound (acoustics) to relay information across open space (telemetry). In our application, UWAF researchers attach acoustic transmitters (or “tags”) to the shark they study. Each tag emits unique sound pulses that are heard and understood by our underwater tracking stations (receivers). As sharks swim through our network of tracking stations, their movements are revealed! The study involves two different type of methodologies: capture sharks and surgically insert an acoustic tag under their skin, or externally tag free-swimming sharks using a modified railgun.
Part of this project is located in the Bazaruto Archipelago National Park (BANP). Here, our researchers investigate aspects of the ecology of endangered sharks through acoustic telemetry and Stable Isotope Analysis (SIA), to modify existing policies to further benefit endangered sharks in the park. Stable isotopes of Carbon and Nitrogen, extracted from shark tissues, will be compared with those obtained from prey items and the environment to estimate shark trophic niches, position in the food web, foraging strategies, and, integrated with the acoustic telemetry results, their movement patterns.
The other study area of the project is sited in Inhambane estuary and Tofo bay. Bull sharks (Carcharhinus leucas) are responsible of at least 12 human attacks over the last three years in the Inhambane Province. Investigating shark movements in the area will allow us to examine the degree of presence of sharks and the importance of mangroves and estuary habitat for these animals. The collected data will be examined along with an awareness project, to educate local communities on good practises to avoid sharks. Attacks happened mainly in the estuary and because fishermen use to clean their caught fish in deep waters, whose blood attracts curious and starving sharks. Since we taught fishermen to clean fish in ankle waters, no shark attack has been recorded.
If you’d like to join our researchers in this shark tracking project, dive deeper in our Volunteer Page, and discover what you can do to protect this amazing animals!
This work is done by boat, and if there is space, the volunteers who have been here the longest get priority spots on the boat; however we cannot guarantee everyone will get a trip out. Safely capturing these large and powerful animals is very challenging and requires a lot of knowledge to predict what these sharks will do.