CONSHARKVATION.ORG

Unmaned Aerial Vehicle Shark Survey

The present project seeks to implement a non-invasive approach to the study of the spatial ecology of a population of smooth hammerhead sharks (Sphyrna zygaena) on Faial island, using an unmanned aircraft (UAV), also known as drone.
It is known the presence of S. zygaena in the Azores archipelago, especially due to its coastal habits during its juvenile phase, highlighting the importance of the ecological services that coastal habitats of the archipelago provide to this species, specially during this phase of the species early development.
To quantify the abundance, the density of individuals in different areas of the coast and their seasonal variation, we intend to evaluate the potential of aerial sampling using UAVs as cost-effective alternative to other conventional sampling methods such as fishing with hooks or the use of baited cameras (BRUVs), which due to their invasive nature imply stress effects or alteration of the natural behavior of the animals.

It is intended to perform an annual sampling, distributed in several stations to assess both the abundance seasonal variations and the areas where there are peak densities, which have the potential to be regarded as a nursery area.

The task is being performed using airborne high-resolution photography and video techniques that allow subsequent analysis in the laboratory. The image processing should allow the collection of data such as counting the number of individuals, assessing the swimming direction, evaluating the density of individuals per area unit throughout the year and identify which are the total length (TL) classes present in the sample.

Fig. 1 : Distribution of the aeral survey sampling stations around the island of Faial with the purpose to study the seasonal abundance and densities of smooth hammerhead (S. zygaena).