Since 2015 the MHI Group has provided support to the "Tanegashima Loggerhead Sea Turtle Survey" program sponsored by the authorized NPO EarthWatch Japan. In this, the third year of the program, a total of six sessions were planned for the period between June and August to tag first the turtles coming to the beach to lay eggs, and later the newly spawned turtles. Regrettably, two sessions in August for the latter purpose had to be canceled due to the effects of a typhoon.
Because loggerhead sea turtles are sensitive to light, marking them with identification tags for research purposes and measurement of their shells, length and width, using a caliper must be performed in the dark. In preparation to do so, the volunteers were given prior instruction on how to conduct the survey, along with points needing special care and attention, by an academic expert and members of Turtle Crew, a local NPO. Then, between 10 p.m. and around 2 a.m. on the designated nights, the volunteers set out on Nagahama Beach, which is on Tanegashima's western side, and elsewhere in search of the arriving sea turtles. When, by following tracks in the sand, they located a turtle, they immediately marked it with an identification tag and measured its shell, all the while making every effort not to disturb its spawning behavior.
The survey program is targeted at protecting loggerhead sea turtles, currently under threat of extinction, by clarifying the survival rate of mature females and their homing rate back to earlier spawning sites. It also seeks to shed light on the incidence of shell mutations involving scute alignment, which have been suggested to have a relationship to these turtles' deformities and rising mortality rate in recent years. The program has also been officially recognized and backed by the Japan Committee of the United Nations Decade of Biodiversity (UNDB-J).
During the four survey sessions most recently conducted, a total of 52 loggerhead sea turtles were encountered, of which 47 were tagged for identification and 34 were confirmed as having spawned. Since MHI first began supporting these surveys, to date 100 turtles have now been tagged, and some turtles tagged two years ago have reappeared, an indication that the program is gradually beginning to produce results. In view of this progress, we are more eager than ever to maintain our support of the survey program in the years ahead.
Going forward, in accordance with our CSR Action Guidelines, the MHI Group will continue to take a variety of initiatives to protect the environment and biodiversity.
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Related news on the surveys conducted in 2016:
Receiving instructions before starting the survey
Practicing how to measure turtle shells
Making a preliminary inspection of the beach
A loggerhead sea turtle spawning
The spawned eggs
Maenohama Beach, one of the survey locations
Participants of the June 30–July 2 survey