Biotelemetry / BiologgingRemote measurements of biological information

using transmitters and recordersOur Biosphere Informatics course sets the challenge to clarify the ecology of

aquatic animals which are not readily visible by using Biotelemetry. Biotelemetry is a new method to monitor, record, and measure a living organism's basicphysiological functions making the best use of information technology. We place small transmitters or recorders on target spices and obtain ecological information of aquatic animals. This is exactly a method to see “what is unseen”. Many fruitful results have been obtained, which have contributed to the research on aquatic animals, being the last remaining frontier on this earth.

Acquisition and analysis of ecological information for coexistence of human beings and species to extinction

We, human beings, being a part of the biosphere need to sustainably utilize biological resources without destroying the ecology. Whilst there still are mysterious things in aquatic ecology, expectations for the possibility of providing the necessary biological resources exist. However, in recent years, the number of aquatic spices has decreased and extinction of spices which will not be utilized as resources is an issue of concern as well. Conservation of these species is becoming a major social problem.

Un-clarified aquatic ecology and aquatic resources

Dr. Hiromichi Mitamura（PD）Research fellow, JSPS

Research on behavioral ecology of fish (rock fish, Mekong giant catfish and others)(Currently researching in Norway

Dr. Tohya Yasuda（PD）Research fellow, JSPS

Breeding ecology of adults green sea turtles

Dr. Junichi Okuyama（PD）

Behavioral ecology and research on conservation biology of hawksbill turtle

Kotaro Ichikawa（D3）Research fellow, JSPS

Acoustic monitoring of dugong by using an automatic sound monitoring system

Yuki Kawabata （M2）

Clarification of blackspottuskfish’s ecology and establishing a releasing technique

Dr. Nobuaki Arai(Associate professor)

Analysis of aquatic animal resource information by Biotelemetry

Takashi Yokota（D2）Research fellow, JSPS

Clarification of Japanese tilefish’s behavioral ecology and establishing a releasing technique

Researchers：

Dugong Sea turtles

Mekong Giant Catfish

Biosphere InformaticsDepartment of Social Informatics

Kyoto University Bioresource Informaticshttp://bre.soc.i.kyoto-u.ac.jp/

Kengo Kataoka（M2）

Research on ecology and re-migration behavior of wild hawksbill turtle

Kouki Nakamura（M2）

Research on behevioralecology of serranidae in mangrove creeks

Nanako Amamoto（M1）

Clarification of feeding behavior by using dugong calls

Satoko Kimura（M1）

Analysis of migration behavior of finless porpoise using an acoustic data logger

Kozue Shiomi（M1）

3D behavior analysis of penguins

Hideaki Nishizawa（M1）

Research on moving ecology of sea turtle juveniles

As of May 2007

Rika Shiraki（M1）

Acoustic analysis of dugong calls

Shoichi Machino（B4）

Sea contamination and behaviors of sea mammals

Takuji Noda（B4）

Development of loggers for behavioral ecology analysis of deep-sea fish

Adelie Penguin

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Passive acoustic observation of rare marine mammals

Dugong (Dugong dugon) (Figure 1) belongs to the genus Dugong of the family Dugongidae, order Sirenia. Its original species was a crying herbivorous marine mammal, which ranged in coastal waters of tropical and subtropical regions. Remaining populations of dugong are reduced in most habitats. In 2000, the IUCN listed the dugong as a species vulnerable to extinction (VU) in the red list.

Coexistence between human activities in coastal areas and rare marine mammal preservation is a key to the sustainable use of the marine biomass. To discover a way which is friendly to both local residents and marine mammals, the data ofmarine mammals’ behavioral tendencies should be collected. In the Biosphere Informatics course, we have observed thebehavior of dugongs and finless porpoises.

Finless porpoise (Neophocaenaphocaenoides) (Figure 2) belongs to the genus Neophocaena, family phocoenidaeof the suborder Odontoceti, order Cetacea, which is less than 2 m in length. The finless porpoise is endangered due to the decline of its population. It is one of the CITES-listed and IUCN red listed species in Annex I of 1973 Washington Treaty. The above picture shows the parent-child finless porpoise living in the Yangtze River in China.

Recently, sea pollution has become more serious, and has had an adverse affect on different marine lives. The situation is most crucial for marine mammals, as higher-predators, in which large amount of hazardous substances are stored up due to bioaccumulation. We need to understand the ecology of marine mammals as well as the accumulative concentration of chemicals in them for their comprehensive preservation. (Machino)

This study intends to find solutions to friction/conflict between humans and animals in coastal areas from the aspect of the animals’ ecology. the Biosphere Informatics course seeks to solve problems in fishing which are closely related to human society through a comprehensive approach based on the science of fisheries, science of information and biology.

Figure 2. Parent-child finless porpoises swimming in a water tank

Figure 1. Dugong feeding in a shallow sea

It is a method to identify the location of dugong or finless porpoises by acoustic analysis of their voices recorded under water (Figure 3, 4). In practice, the intersection of arrival directions of a stereo recorded voice is used to identify the location. The impact on the behavior and ecology of dugong or finless porpoise can be minimized using this method.

What is “passive acoustic observation”?

AUSOMS-D

Figure 3. Concept of passive acoustic observation of dugong

Figure 4. Gates for passive acoustic observation of finless porpoise

W20-ASII

Figure 5. Sonogram of dugong voiceIt indicates a little bird-like cheep voice.

Figure 6. Activities of dugong

It is observed that dugong become active (produce cries) in the night-time, especially 3:00 to 6:00. (Ichikawa)

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0Figure 7. Sound pressure of sonar sound of finless porpoise (Pa) (Upper) and time series of change of arrival directions of sound (Lower)

This indicates that onefinless porpoise swamfrom upstream todownstream. (Kimura)

Figure 8. Feeding sound of dugong

The sound of dugong’s eatingseagrass (F) was recorded. It isobserved that it manducates at a regular interval.

It is also observed that the dugong feeds in mudland in the night-time. The reason why it looks for foods in mudland, which is dangerous for itself, is now studied. (Amamoto) Figure 9. Acoustic logger for dugong

耐圧容器 ICレコーダー

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耐圧容器 ICレコーダー

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ハイドロホンIt is attached to thedugong directly to recordits voice, and is underdevelopment (Figure 9).It is expected that thistechnology will help todetermine the relationshipbetween mother and child.(Shiraki)

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Swimming mode and distribution process of young turtles.

Habitat of subadult turtles

Breeding of adult turtles

Left: Adult green sea turtle laying eggs on the beachLower: Swimming route of green sea turtles in(a) Gulf of Thailand and (b) Andaman Sea

Adult sea turtles move from their feeding location to their hatching location (beach) every 3 years. The distance between these two locations can be several thousand kilometers. Adult female sea turtles lay eggs every 2 weeks during the breeding season, and can take place a maximum of 10 times. Incubation generally occurs in the warmest season.

In the Biosphere Informatics course, werecord the swimming/ diving behavior ofadult green sea turtles (swimmingdistance/ diving depth) by electronic tag inorder to study its relationship withincubation season/ number of eggs. (Yasuda,Okuyama)

To release farm-raised sea turtles, it is necessary to consider whether they can successfully reach the open ocean and whether they can adjust themselves in the ocean environment. For this purpose, the swimming performance of sea turtles is observed based on moving speed, moving direction, and frequency of strokes, covering different stages of growth. The purpose of this observation is to find the best way of release to ensure their preservation. (Nishizawa)

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Upper-left: Wave profile of strokes obtained by acceleration data loggerUpper-right: Change of frequency of strokes based on stages of growthLower: Moving route of juvenile turtles based on stages of growth

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Subadult Hawksbill turtles, which are well-known by the Japanese as the material of tortoiseshell, are found in Yaeyama Islands of Okinawa. We are nowtrying to understand the ecology of the subadultHawksbill turtles by using a device to record watertemperature and diving depth, which is to beattached to their shell. It was previously considereddifficult to collect a recorder attached to free-swimming marine animals. However, this device solvessuch problems, as it will be automatically releasedfrom turtles by a timer and come up to the surface.(Kataoka)

Left: Hawksbill turtle attached with recorder with automatic release timerLower: Diving data of Hawksbill turtleobtained fromrecorderDepth

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Sea turtlesSea turtles have an extraordinary sense of location. Their habitant varies from hatching to breeding, including beach, open ocean and coastal areas. In the Biosphere Informaticscourse, we conduct comprehensive surveys on sea turtles, from hatchlings to adults, in orderto understand their life history, especially their change of behavior and habitant based onthe phases of their life, by behavior patterns to be obtained from electronic signals anddata of the surrounding environment. The Yaeyama Islands of Okinawa (subtropical region)and southern Thailand (tropical region) are selected as survey areas. Our survey mainlycovers Hawksbill turtle (Eretmochelys imbricata) and green sea turtle (Chelonia mydas).

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The red tilefish is the premium fish used for a Kyoto specialty, called “guji” in Japanese. Since its remaining source has decreased, it is covered by the “farming fishery” program. Meanwhile, the ecology of its original species living in the muddy seabed in the offing is not known. Since 2002, we have conducted the tracking observation of red tilefish (both natural and farm-raised ones) by ultrasonic telemetry. Most of the signals from each individual are received in the daytime, whilst only a few in the night-time (Graph (a) in the left). We assume that the original species has the diel motion that it digs a hole in the seabed as a nest, gets out of the nest in the daytime, and stays in the nest in the night-time. On the other hand, the reversed cycle (stay in the nest in the daytime and get out of the nest in the night-time) was found in some of farm-raised individuals (Graph (b) in the left). (Yokota)

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Upper: Red tilefish just after releaseRight: Number of signals received for one hour ((a) natural fish (b) farm-raised fish)

Black-spot tusk-fish (Choerodon shoenleinii) (local name: Makboo), is a very valuable fish, one of the three most premium fish of Okinawa. Due to the decrease in fish catch, farm-raised ones have been released to recover the source. In the Biosphere Informatics course, we have surveyed “what”, “when” and “where”such farm-raised black-spot tusk-fish do under the natural environment by using ultrasonic telemetry. According to our survey, half of released black-spot tusk-fish stayed near the release point for more than half a year after release and then expanded their scope of activities gradually. Also, the obvious diel motion is observed, i.e. they stay at the seabed in the night-time, whilst swimming 10-20 m below the surface of the sea in the daytime. (Kawabata)

Upper: Adult female black-spot tusk-fishLeft: Typical vertical and horizontal movements of black-spot tusk-fish released in October 2006 (Grey area indicates the nighttime.)

船による追跡

設置（待ち受け）型受信機双曲線位置決定用の

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The Mekong giant catfish (Pangasianodon gigas) is the largest freshwater fish in the world, found only in the Mekong river. It grows to nearly 3 m in length and 300 kg in weight. In 2001, based on the request of the Thai government, we implemented the Mekong giant catfish tracking project by the bio-telemetry method in the Mekong river and an artificial lake (Mepung Lake) in order to understandits ecology. Through the project, it wasobserved that the Mekong giant catfishis active in vertical movement in thedaytime, while such activity is hardlyfound in the night-time. (Mitamua)

We have surveyed the behavior of valuable fish by using ultrasonic bio-telemetry. The approach methods used vary, including pursuit by ship inresponse to movement of fish, to setting a fish-finder under water.Recently, a data logger, which is attached to fish and automaticallyreleased for collection, has been developed.

Species covered in the previous survey using a transmitter:Mekong giant catfish, red tilefish,black-spot tusk-fish, rockfish,marbled rockfish, bass, red seabream, black sea bream, moonjelly, yellowtail snapper, bluefintuna, sea eel, Atlantic codfish,lumpsucker, saithe, European eel,etc.Ultrasonic transmitter

(V16, V8, Vemco)Stand-type receiver

(VR2, Vemco)

Fish behavior tracking~for sustainable catch of valuable species~

Mekong giant catfish

Right: Mekong giant catfishUpper: Diurnal vertical movement of the Mekong giant catfish

Red tilefish

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