Sountraps are autonomous recording systems, very useful for passive acoustic monitoring, and can also be used as regular hydrophones. If attachedd to a mooring it can record underwater sounds for days in a row, very useful to detect presence of animals in a certain area, obtaing data on vocal repertoire and the sound recordings can be used as a proxy for habitat use. In Mocajuba we set up three soundtraps at the market surroundings and offshore in the river main channel. We obtained lots of interesting data that we hope to share soon with the scientific community and the local people from Mocajuba.
As today was the last day of our fieldwork and also Ocean Conservancy's International Coastal Cleanup Day we took the chance to conduct a environmental education action in Mocajuba, we invited the local community to join us and clean up the munical market area and beach on the riverfront. We collected the about 350kg of trash! The idea is to start a change of attitude in the people of Mocajuba so they give proper treatment to their trash instead of throwing them in the river and risking the health of humans, botos and all the aquatic community. Today local children and adults joined our team! We are really thankful for the participation of Mocajuba's population in today's action and for their collaboration all along our fieldwork! It was amazing! We will be posting more from our research in the coming days! Stay tuned!
Botos are not the only dolphins inhabiting the Tocantins River, there one can also find tucuxis (Sotalia sp.). Therefore, to obtain behavioral and acoustic data on tucuxis and also of botos away from Mocajuba Market we have been conducting boat surveys every afternoon. This data will allow us to compare sounds produced by both species and how they use sounds to navigate in such complax environments as the Amazonian Rivers.
The market of Mocajuba not only presents a good opportunity for tagging, but also to collect a bunch of biological information. During the past days we have been collecting tissue samples using thimbles, blow samples using stockings attached to a plastic hoop and doing continuous sound recordings using soundtraps.
Even though the market of Mocajuba presents a unique opportunity to tag botos and it is really easy to deploy the tags to keep them attached is quite a challenge. With their incredibly flexible bodies botos are able to rub the off on the bottom of the river or against each other. Some times they use their pectoral fins to remove it. We are currently trying new protocols to increase the attachment time.
Let's hope thet we will have good news soon!
After a long trip on the 3rd of September yesterday we started our activities in the market of Mocajuba. We started by deploying one of the soundtraps (an autonomous recording system) to record dolphins sounds continuously while we observed botos and identified each individually. Later on we decided to test different types of temporary taggings to keep track of all individuals visiting the market on that day, we tried an zinc oxide oitment, lipstick and chopstick. The marks we made were visible, but as dolphins are frequently touching and rubbing against each oother they fade out easily. However we were able to begin a catalog of individuals based on their natural markings, and temporary tagging helps to identify when a new boto comes by.
Today we will try tag deploying for the first time, fieldwork looks promising.