Sampling methods
Biologging study
We use animal-borne data loggers to monitor behaviors of free-ranging carp.
Step 1
Firstly, we anaesthetize a fish and measure its body length and body mass. We also take a tiny tissue from its fin for DNA analysis.

Step 2
The fish is then tagged with a ribbon tag and a logger package. The package consists of four electronic devices (a video logger, an accelerometer, a VHF transmitter, a timed-release system) which are all molded in one float.

Step 3
After the tag attachment, the fish is released into the lake. The loggers record behavioral data (3–5 days) and underwater video images (~12 hours).

Step 4
The logger package pops off from the fish and floats to the water surface.

Step 5
We search for the package using a VHF receiver and antenna and retrieve the package.

Step 6
Download behavioral data and videos from the loggers.

Members
Makoto A. YOSHIDA

Makoto A. YOSHIDA (Ph.D.)
Research Associate
Lake Biwa Branch Office / Biodiversity Division, NIES
Kohji MABUCHI

Kohji MABUCHI (Ph.D.)
Senior Researcher
Lake Biwa Branch Office / Biodiversity Division, NIES
Katsufumi SATO

Katsufumi SATO (Ph.D.)
Professor
Atmosphere and Ocean Research Institute, The University of Tokyo