Tatsuro Matsuoka

Kagoshima University, Kagosima, Kagoshima, Japan

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Publications (25)20.15 Total impact

  • NIPPON SUISAN GAKKAISHI 01/2013; 79(5):879-880. DOI:10.2331/suisan.79.879 · 0.15 Impact Factor
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    ABSTRACT: The fisheries structure, fishing gear, fishing vessels and their ownership, landing sites and markets, as well as fisheries management and fishers’ participation were surveyed in three tropical islands: Pohnpei (Micronesia), Mafia (Tanzania), and Guimaras (Philippines), covering 127 fishers. Labour-intensive gear, including purse seines and ring nets, characterised Mafia fisheries. Fibre-reinforced plastic (FRP) boats characterised Pohnpei fisheries, and canoes with nonmarine engines were characteristic of Guimaras fisheries. Wooden plank boats with large crews were only seen in Mafia. From a gear/vessel ownership perspective, the fisher categories present were gear fishers, gear-vessel fishers, employers, and casual labour fishers. Casual labour fishers and employers were only apparent in Mafia. The fisheries in Pohnpei had a relatively early age of entry, which was attributed to the urban markets available and family cohesion, while community organisation-based management of these fisheries was weak. Mafia and rural Guimaras fishers depended on middlemen, due to the distance of the market. Deteriorating subsistence-related fishery dependency means that the Guimaras fishers’ community is at risk. The high shared gear/vessel ownership rates and levels of affiliation to community organisations in Mafia reflect government’s timely community sustainability enhancement initiative. Based on our analyses, we propose the “fishers’ community sustainability” concept. The sustainability of a fisher’s community can be judged on (1) the age of entry to the fisheries, (2) the monetary profits made at fish markets and through marketing, (3) the cohesion among the fishers, and (4) the level of subsistence-related dependency on the fishery. The fishery is key to community sustainability, thus ensuring fishery-dependent life. It is essential to consider the above indicators of fishers’ community sustainability during fisheries development.
    Fisheries Science 07/2012; 78(4). DOI:10.1007/s12562-012-0500-x · 0.86 Impact Factor
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    ABSTRACT: Antennules have been reported to influence localization of distant food odors, sex discrimination, and agonistic and social behaviors of decapod crustaceans. Although olfaction by the antennules is largely recognized, information on the sensitivity of antennules to hydrodynamic stimuli has been scant. In red swamp crayfish Procambarus clarkii antennules, mechanosensory setae outnumber the chemosensory setae. We studied the mechanosensitivity of crayfish antennules by recording neural activities from isolated antennules in response to sinusoidal dipole stimuli. Both the lateral and the medial flagellum of the antennules responded to hydrodynamic stimuli, although the medial flagellum showed more sensitivity at frequencies higher than 60 Hz. The most dominant setae present on the stimulated site were the simple setal type. Although both lateral and medial flagella are capable of detecting chemical and hydrodynamic cues, results from neural responses, morphological observations and antennular behavior observations indicate that the lateral flagellum of P. clarkii functions as an olfactory organ whereas the medial flagellum complements as a hydrodynamic receptor. It appears that in crayfish antennular sensory processing, crayfish simultaneously use chemical and hydrodynamic information. We have compared our data with the threshold of fish lateral line to the same stimuli and we discuss probable similarities in response properties.
    Journal of Experimental Biology 11/2010; 213(Pt 21):3683-91. DOI:10.1242/jeb.046011 · 3.00 Impact Factor
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    ABSTRACT: Following the oil spill accident of the Solar I tanker in 2006 off the coast of Guimaras Island in the Philippines, polycyclic aromatic hydrocarbons (PAHs) and alkylated PAHs in some aquatic organisms were investigated at Luzaran in Guimaras and Taklong Islands, which were heavily polluted with spilled oil, immediately and 1 month after the accident. The concentrations of total PAHs were 11.9-52.3 ng/g dry weight in fish. Meanwhile, total PAH concentrations in shellfish were 38.0-3,102 ng/g dry weight in Luzaran and 128-236 ng/g dry weight in Taklong. Pyrene, phenanthrene, and fluoranthene were dominant in most fish and chrysene in all shellfish. Significantly higher concentrations of all alkylated homologs were detected in shellfish than in fish. These differences had two possible causes, that is, the differences between fish and shellfish could be attributed to the uptake routes and/or their metabolizing abilities.
    Environmental Monitoring and Assessment 06/2010; 165(1-4):501-15. DOI:10.1007/s10661-009-0962-1 · 1.68 Impact Factor
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    ABSTRACT: Pesticide residues in five freshwater areas that are directly affected by rice paddy effluents in southern Japan were measured to determine their maximum concentrations and temporal variations. Water samples were collected every week during the 2005 rice planting season in Kagoshima Prefecture and stations were established in Amori River, Sudo River, Nagaida River (that drains into the bigger Kotsuki River), rice paddy drainage canal, and wastewater reservoir (that collects effluents from rice paddy fields). Of the 14 target pesticides examined, a total of 11 were detected in all stations. Mefenacet, fenobucarb, and flutolanil were the three pesticides with the highest maximum concentrations and were also detected frequently. Analysis of temporal variations of pesticides showed that herbicides had relatively higher concentrations in the earlier stages of the rice planting season, while insecticides and fungicides had relatively higher concentrations at the later stages. There was no significant difference among stations with regards to the temporal patterns of the top three pesticides. The calculated toxic units were less than 1 in all stations, implying low or negligible environmental risk of pesticides detected to freshwater organisms.
    Environmental Monitoring and Assessment 01/2010; 160(1-4):371-83. DOI:10.1007/s10661-008-0701-z · 1.68 Impact Factor
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    ABSTRACT: The effects of pollution on fishing activities were evaluated. Using a prepared questionnaire, fishers, village heads and fishery officers in three study sites in Panay Island, Philippines were interviewed. Respondents identified sources of pollution in their area and described how these affected their fishing activities. Effects of pollution with reference to several indices in capture fisheries, e.g., catch volume, fishing frequency and duration, operation costs, and catch composition, were determined.
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    ABSTRACT: The food intake and prey composition of payao-associated Brama orcini were compared with individuals captured in open waters from February to May 2005 in Panay Gulf. An experimental multi-hooked handline was used to catch fish at the two sites. The food items of payao-associated and free-swimming fish in this fishing ground overlap; however, the total frequency of occurrence and abundance of all prey items were both higher in free-swimming fish than in payao-associated individuals. Invertebrates seemed to be preferred by this fish, and the ratio of prey weight to its body weight was significantly higher in unassociated fish than in fish caught near payaos. In open waters, B. orcini feeds predominantly on the sergestid shrimp Acetes sp., but it alters its diet by feeding on the small finfish that also aggregates near the payaos when the fish is associated with the floating structures. These results should be verified since they may be useful in managing the fishery resources aggregating near payao.
    Fisheries Research 01/2009; 95(1):132-137. DOI:10.1016/j.fishres.2008.07.011 · 1.84 Impact Factor
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    ABSTRACT: Sound generated by a payao, an anchored bamboo fish aggregating device, is believed to be attractive to fish; but until now, there is no available record of payao-generated sound. This study presents payao-generated sound recorded by a hydrophone at water depths of 5, 10 and 15 m from a fixed distance of 3 m relative to the payao, and compares the sound with the auditory sensitivity of jack mackerel Trachurus japonicus measured at discrete frequencies from 100 to 2000 Hz using the auditory brainstem response protocol. A consistent peak appeared in the sound spectrum at 49 Hz and showed an increasing sound pressure level with depth, which suggests that payao sound may come from the anchor rope. However, the contribution of the bamboo raft can not yet be discounted. The hearing threshold curve indicated that the most sensitive frequency range in jack mackerel is from 92.1 dB at 800 Hz to 111.0 dB at 200 Hz. These results show that the dominant frequency range of payao sound does not correspond with the high sensitivity frequency range of fish hearing.
    Fisheries Science 12/2008; 74(6):1207 - 1214. DOI:10.1111/j.1444-2906.2008.01644.x · 0.90 Impact Factor
  • Bioacoustics 01/2008; 17:54-57. DOI:10.1080/09524622.2008.9753762 · 0.73 Impact Factor
  • Kazuhiko Anraku, Tatsuro Matsuoka, Kenji Watanabe
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    ABSTRACT: Hydrodynamic static pressures on the body surface of fish generated by conspecifics parallely swimming were measured in a flume tank, and they were compared with those generated by changing the position of two individuals under different flow velocities. Two dead common carp (BL=20 cm), fixed in 20% of formalin, were used. Pressure was measured by a manometer connected to the ends of three aluminum pipes (inner diameter=3 mm), which were inserted perpendicularly to the body axis from right to left in the control fish. The openings of the pipes were located on head, trunk, and caudal regions, and each was on the infraorbital or trunk canal lateral lines. The target fish was moved on the horizontal XY plane using a traverse device. Although pressures changed depending on the regions measured, changes of pressure according to position and current velocity were relatively low in the caudal region. The absolute values of the pressure increased as flow velocity increased, and decreased with an increase in the distance between individuals. Relative positions when the maximum pressure changes were observed at each flow velocity did not change, indicating that pressures were largest when the maximum body width of the conspecific is closest.
    The Journal of the Acoustical Society of America 01/2006; 120(5):3105. DOI:10.1121/1.4787566 · 1.56 Impact Factor
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    Tatsuro MATSUOKA, Toshiko NAKASHIMA, Naoki NAGASAWA
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    ABSTRACT: Research on ghost fishing became active in the late 1980s. Ghost fishing has been confirmed for traps, gillnets, trammel-nets and small seine nets. Some lost traps are functional for a long period of time, even in shallow waters. Consequences for gillnets after loss depend on seabed conditions. The ghost fishing function of gillnets remaining on flat seabeds declines rapidly with decreasing heights and increasing visibility. Gillnets left tangled around an artificial reef, for example, three-dimensionally maintain the initial magnitude of ghost fishing for a long period of time, even after badly fouled. There are increasing numbers of researches working on the total number of mortality per gear after gear loss for gillnets and trammel-nets. It has become also possible to estimate the total number of mortality for a unit period of time in a certain fishing sector. This paper reviews research which has provided evidence and quantitative data on ghost fishing, and proposes five items important for future studies on ghost fishing.
    Fisheries Science 07/2005; 71(4):691 - 702. DOI:10.1111/j.1444-2906.2005.01019.x · 0.90 Impact Factor
  • TOSHIKO NAKASHIMA, TATSURO MATSUOKA
    NIPPON SUISAN GAKKAISHI 01/2005; 71(2):178-187. DOI:10.2331/suisan.71.178 · 0.15 Impact Factor
  • TOSHIKO NAKASHIMA, TATSURO MATSUOKA
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    ABSTRACT: The ghost-fishing ability descending over time and ghost-fishing mortality were quantitatively evaluated for a lost bottom-gillnet. Three experiments were conducted for a maximum period of 1,689 days since deployment of a net. The number of ghost-fishing mortalities per day per net was determined by underwater observation of enmeshed fish on two consecutive days. Mortalities were recorded continuously around the start of experiments and intermittently during the following period. The consistent faunal character around the net was confirmed and the number of mortalities was assumed to reflect the change in the ghost-fishing ability of the net. The decline in ghost-fishing ability over time was represented by a sum of two formulae, which reflect two ghost-fishing factors effective respectively for short and long periods of time. From this analysis, the effective ghost-fishing duration which was defined as the time elapsed to the day when the value of the equation declines to 5 percent of the original fishing ability of the net was 142 days during which the total number of ghost-fishing mortalities was 455 fish. Ghost fishing for red sea bream, Pagrus major and jack, Decapterus sp. occurred in the first short period and for filefish Stephanolepis cirrhifer, over a longer period.
    NIPPON SUISAN GAKKAISHI 09/2004; 70(5):728-737. DOI:10.2331/suisan.70.728 · 0.15 Impact Factor
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    ABSTRACT: Sinking motions of tuna longlines at the surface layer, 0-30 m depth, were studied at sea by using depth loggers attached to the bases (main lines) and tips (hooks) of branch lines. Characteristic sinking patterns and changes in sinking velocity were compared between main lines and hooks. Initially, main lines and hooks sank at different velocities; the main lines sank at 7.7 +/- 1.5 cm/s and hooks at 18.7 +/- 3.6 cm/s. There was no significant relationship between the velocities and the duration of the initial sinking. Deceleration for hooks started 36 to 112 s after shooting. Consequently, their sinking velocities became identical to those of the main lines. The sequence of sinking motions of a main line and a hook can be modeled as three stages: independent free fall at their own velocities where a hook sinks faster (initial motion), deceleration of a hook after the branch line is stretched (transitional motion) and simultaneous sinking of a main line and a hook which is suspended from the main line (final motion). The above model suggests that casting of stretched branch lines results in a prolonged sinking time to the critical depth for a hook.
    NIPPON SUISAN GAKKAISHI 01/2004; 70(1):48-53. DOI:10.2331/suisan.70.48 · 0.15 Impact Factor
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    ABSTRACT: Abstract The effects of exposing the taste receptors to two common aquaculture therapeutants, potassium permanganate (KMnO4) and formalin, on the gustatory responses in the Nile tilapia Oreochromis niloticus (Linnaeus) were studied using an electrophysiological approach. Electrical responses to the stimuli before and after perfusing the receptors with the toxicants were compared. Responses to 1.0 mM l-methionine (l-met) were significantly reduced when the receptors were perfused with 2.0 mg L−1 KMnO4 or 200.0 mg L−1 formalin. KMnO4 suppressed the responses to 56%, whereas formalin reduced them to 83%. Both toxicants reduced the responses to l-arginine to a similar extent to that of l-met, indicating that the action of the toxicants is not specific for the receptor sites for amino acids. On the other hand, the toxicants suppressed the responses to quinine significantly more than those to amino acids, which indicates that the transduction pathways for bitter substances are much more sensitive. The suppressions were reversible, suggesting that these toxicants do not cause any permanent damage to the physiological features of the taste receptors, but only interfere with their normal functioning. The possible mechanisms of suppression and their consequences on the feeding process are discussed.
    Aquaculture Research 05/2002; 33(6):445 - 453. DOI:10.1046/j.1365-2109.2002.00694.x · 1.42 Impact Factor
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    ABSTRACT: Abstract The gustatory sensitivity of the Nile tilapia, Oreochromis niloticus L., to different amino acids was studied using an electrophysiological approach. The electrical responses were recorded from a branch of the facial nerve innervating the external taste buds of the upper lip. The relative stimulatory effectiveness (RSE) of nine amino acids and betaine were determined at a concentration of 1 mmand all of them elicited neural responses. This species responded well to the neutral, basic and acidic amino acids. The most stimulatory amino acids were L-histidine, L-arginine, L-serine, L-methionine and L-glutamine; L-proline and betaine were the least stimulatory. The results of this study suggest that the Nile tilapia has high external gustatory sensitivity to some amino acids as a physiological adaptation to search effectively for their sources. The effect of the pH, ranging from 4.0 to 9.0, on the RSE of three neutral amino acids and artificial pond water (APW) was also studied. The RSE increased below pH 6.0 and was relatively unaffected from 7.0 to 9.0, indicating that acidified stimulants are highly stimulatory in this species. Nile tilapia did not discriminate the pH of APW as effectively as some of the species studied earlier.
    Aquaculture Research 03/2001; 32(3):217-222. DOI:10.1046/j.1365-2109.2001.00550.x · 1.32 Impact Factor
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    ABSTRACT: A four-month market survey revealed that at some mariculture centers in Japan, over 90% of red sea bream reared in captivity possess a deformed single nasal opening as compared with normal fish with anterior and posterior nasal openings at each olfactory organ. The deformity occurred at day 32-40 after hatching when the medial and lateral epidermal lips failed to form the septum that separates both olfactory nares. The authors also demonstrated that the fish reared in captivity have no problems feeding on pelleted diet but their wild counterparts do not accept non-living food even under a long period of starvation. Differences in olfactory system between wild and cultured fish are discussed especially in reference to the olfactory system and fish behavior
    OCEANS, 2001. MTS/IEEE Conference and Exhibition; 02/2001
  • Nihon-suisan-gakkai-shi 01/2000; 66(3):439-445. DOI:10.2331/suisan.66.439
  • Nihon-suisan-gakkai-shi 01/1997; 63(2):145-151. DOI:10.2331/suisan.63.145
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    ABSTRACT: To examine the attractiveness of coloured fish aggregation devices (FADs), six sets of four to six FADs of the kite type were deployed in coastal waters and dive observations were carried out for 15 months. The FADs had the same dimensions but different kite colours: white, black, blue, green, yellow and red. Fish abundance and aggregation patterns around the FADs were scored and statistically analysed. Fish tended to be most abundant near the blue and green FADs, least abundant near the black and white FADs, and intermediate near the yellow and red FADs. Aggregations stayed closer to green and blue FADs than to white, yellow, black or red FADs. The more attractive FADs were the less visible ones. Thus, fish were attracted to blue and green FADs on the basis of hue rather than contrast.
    Fisheries Research 08/1996; 28(1):99-108. DOI:10.1016/0165-7836(96)00478-X · 1.84 Impact Factor