Thresher sharks (Alopias spp.) have just recently been added to the Convention on International Trade in Endangered species (CITES, Appendix II) (CoP17 Prop.43). Their family is among the most vulnerable of all pelagic species and it is estimated that the population has declined around 83% due to bycatch and target fisheries.
Our project aims to initiate the conservation of Alopias pelagicus at the local scale by providing information on population-risk status and habitat. The information is needed to support both the local government and the national government in implementing the Indian Ocean Tuna Commission (IOTC) resolution for TS conservation and management.
Our project, Thresher Shark Indonesia, is the first thresher shark conservation effort in Indonesia. Last year during our first year of operation, we were able to complete the following objectives in the Alor regency, where our project has been based.
-Use fisheries surveys, satellite tags, and citizen science to find out the habitat-use and species abundance in the main fishing and diving ground.
-Use socio-economic surveys to assess the fisheries dependency of thresher sharks to fishing communities as the information to identify future alternative livelihoods
-Develop education materials and programs to raise community awareness and stakeholders about the importance of thresher shark conservation for long-term sustainability
In total, there are 18 fishermen in the two main towns with medium-sized boats that go out and target Thresher sharks. Tuna and snapper are the most valuable catch for them, but at times when it’s not possible to catch these fish, the fisherman target thresher sharks as they are considered a valuable catch. Thresher shark is not valued for specific traditions or cultures. They target them when they cant catch other things. The meat is more valuable than the fins. Catching thresher sharks is a form of subsistence fishing for these villages.
Throughout our time in the field, we documented 50 Thresher sharks landed. Out of the 50, 26 individuals were female and 12 were pregnant. April was the month with the highest amount of Thresher sharks caught in Alor.
We collaborated with dive centers/resorts around Alor by providing them the thresher shark sighting logsheet. The log sheet was used to identify the main thresher shark dive sites where thresher sharks frequently visit. Dive centers were voluntarily asked to fill the daily sighting logsheet and regularly submit the data to our team.
We are the first group tag Thresher sharks in Indonesian waters.
MiniPAT satellite tag was used to identify the movement and home range of the thresher shark. Our satellite tag data revealed that the sharks moved north toward the Banda Sea, then south toward the East Nusa Tenggara Waters (Savu Sea). This data has provided vital information about the Thresher shark movement in the Savu Sea, one of the largest Marine Sanctuary and one of the most productive fishing areas in Indonesia. We invited local shark fishermen to aid us in the shark tagging process. Collaborating with the local shark fishermen in this has allowed us to build trust amongst the local fishing community. We were also able to learn about and incorporate the local knowledge of these experienced shark fishermen to better understand the process of how to find, attract, and catch Thresher sharks. Based on local knowledge, we learned that Thresher sharks are usually more abundant during the upwelling season, therefore increasing fishing activities focused on thresher shark.
Socio-economic data was collected quantitatively and qualitatively through questionnaires and focus group discussions. We conducted meetings with stakeholders in order to assess community perspective on thresher shark fishing and identify possible future alternative livelihoods to substitute thresher shark fishing. The goal of this activity is to inform stakeholders about project findings as well as obtain input and develop a plan for Thresher Shark Protection in the Alor region.
Our surveys found that the fisherman generally does not understand the importance of marine conservation, specifically, they did not understand why it is important to protect the Thresher sharks of Alor. They originally thought that increased protection towards Thresher sharks in the area would livelihood. However, the fisherman agreed that they would contribute towards the conservation of thresher sharks as long as their livelihoods are protected via alternative sources.
We conducted conservation outreach activities at two main thresher shark fishing villages and two Universities. We also created a Thresher shark storybook for younger students to learn about Thresher shark biology, threats, and conservation efforts.
Thresher shark fishing in Alor was previously unknown to local government institutions. Our project opened the possibility for the continuous data collection on fisheries and habitat data of this species in the eastern region, in which there was a severe lack of.
Our socio-economic research activities have successfully engaged the community and relevant stakeholders about thresher shark issues in the Alor region. The outreach activities successfully delivered to 141 local students in elementary schools in both shark-fishing villages, 113 university students from two Universities, and 17 youth community and local organizations. We also extended the outreach to local Radio, Newspaper, and Alor Expo Event which raised awareness about thresher shark ecology and habitat within the Alor region to the general public.
It is important to note that the project has brought the attention of the Alor Regent Government, as a result of extensive promotions from Radio, expo and word of mouth. Regent Government, Bapak Amon Djobo, as the current regent of the Alor region directly invited project team members to present research findings in his office. Regent Government expressed his commitment to support thresher shark conservation in the Alor region. Listing thresher shark conservation within Rencana Pembangunan Jangka Menengah Daerah (Regional development plan for five years period) is proposed in the discussion, in which the species would potentially be protected locally under Regent’s Regulation as a flagship species in Alor. This special attention has opened the possibility to create a much larger impact on our future project.