著者

Shibata Keishi

出版者

長崎大学水産学部

雑誌

長崎大学水産学部研究報告 (ISSN:05471427)

巻号頁・発行日

no.22, pp.105-108, 1967-03

著者

田村 修 高 良夫

出版者

長崎大学水産学部

雑誌

長崎大学水産学部研究報告 (ISSN:05471427)

巻号頁・発行日

no.3, 1955-06

---

The differences between the types of Pneumatophorus japonicus (HOUTTUYN) and P. tapeinocephalus (BLEEKER) were examined in the gill rakers, pectoral fin rays, some body proportions and interneural spines. The main materials were large- and middle-sized fishes. 1. In regard to the lower gill rakers of the first gill arch, the type of P. japonicus has more than 27, that of P. tapeinocephalus has less than 26. 2. In the former pectoral fin rays are generally less than 20, in the latter more than 20. 3. In body proportions, the differences between the both types are recognized in the distance from the distal end of snout to second dorsal fin origin and that from the distal end of snout to anal fin origin. 4. The interneural spine (reported by Dr. Murakami) is also discussed, it seemes to be more accurate than by gill raker to distinguish two types.1.佐世保近海産の小サバ(体長13~21cm)92尾,中サバ(19~26cm) 99尾,大サバ(28~38cm)50尾合計241尾につき,其の第一鰓弓の鰓耙数・胸鰭軟条数・体比例を計測した.2.第一鰓弓の鰓耙数は特に下肢上の鰓耙数に於てゴマサバとマサバを区別するに適し,24~26本がゴマサバ,27本以上がマサバで其の誤差は3~8%である.3.胸鰭軟条数に於ても差異あり,18・19はマサバ,21・22は殆んどゴマサバである.4.体比例では体高・体幅以外に吻端より第二背鰭・臀鰭迄の長さの頻度分布のモードに差異が現われ,又其他にも頭長等異なる処がある.5.尚村上・早野氏により発表された担鰭骨数をも検査し,我々の資料に於ても之が甚だ良い識別点となることを認め,之と斑紋及び鰓耙数との相互の関係を検討した.

著者

梶原 武

出版者

長崎大学水産学部

雑誌

長崎大学水産学部研究報告 (ISSN:05471427)

巻号頁・発行日

vol.11, pp.49-63, 1961-08-31

---

Investigations of attaching materials and animal fouling organisms on the test nets were carried out at the Stations in Sakibe Inlet of Sasebo Bay from 1958 to 1960. During this period, a series of test nets were installed monthly and replaced the exposed nets for one month, two and three. A test net was constructed by the seven pieces of cremona nets (20s/9, mesh length 50mm, 10×10 mesh) spread over the frame which eight bamboos (dia. 2cm, length 60cm) were joined with two hemp-palm ropes (dia. 5mm) at intervals of one meter. It was suspended from the surface to seven meter depth below, weighted with stones. The fouling animals on the nets were counted and weighted. About bamboos and ropes, the areas occupied with animals were measured. 1. The rich fouling fauna were found in early summer and autumn, i.e., Hydroides norvegica, Styela plicata, Bugula califoarnica, B. neritina, Costazia costazii, Mytilus edulis, Balanus amphitrite albicostatus, B. trigonus and Amphipoda were abundant from spring to summer and H. norvegica, Serpula vermicularis, S. plicata, B. neritina, B. amphitrite communis in autumn. But peaks of several species of compound ascidians and Ciona intestinalis occurred in cold season. There can be recognized an active and a resting period of fauna in a year, the former begins in May and continues to November, and the latter seems to extend from December to April. 2. Generally the beginning of settlement of fouling animals were found earlier on long exposed nets than fresh nets. This phenomena may be explained that the fine attaching materials which were formed on old nets provide suitaple conditions for settling. 3. The characters of suspended solids in the sea water appeared to play a major role in determining the variability of the fouling populations. Also the interrelationships among various species of fouling community give deep influences to the population density and attaching constructions. Therefore grouping member of community through by ecological factors as sessile form and food habit etc., may offer the positive view points to the fouling faunas. 4. Fouling animals of sessile type, as Balanus, we called the primary fouling animals, and the moving fouler on attachment surface, as Amphipoda, the secondary fouling animals. The former consists of groups which feed on the suspended matters by filter, but the latter mainly on the detritus.佐世保湾崎辺浦で1958年以降,試験網の浸漬による付着物の研究をおこなってきた.この資料に基いて,網竹綱の三つの基盤に付着した付着生物の季節消長の概要をのべた. 1 付着生物の付着と生育の旺盛な時期は5~7月,9~11月の年2回みられ,冬期は付着種類は少なくなる.夏期8~9月は付着種類はやや減少するが生育はかなり盛んである.2各季の主な種類は,5~7月ではカサネカンザシ,ナギサコケムシ,フサコケムシ,コブコケムシ,ムラサキイガイ,タテジマフジッボ,サンカクフジツボ,Amphipoda,シロボヤであり,秋期におおいのは,カサネカンサジ,シロボヤ,ヒトエカンザシ,サラサフジツボ,フサコケムシであった.また12~4月におおいのは,Amphipoda,群体ボヤ,ユウレイボヤである. 3 本水域の優占種は,カサネカンザシーシロボヤである.またここでの付着生物群集の性格は,カサネカンザシ(フサコケムシ)―シロボヤ(ムラサキイガイ)―サラサフジツボ(タテジマ)―Tube-buildingAmphipodsにより代表されるものと考える. 4 おおくの種類は,浸漬期間の長い基盤に新らしい基盤よりも早い時期から付着がはじまる.これは古い基盤の付着ヌタが生物の付着や生育に好条件となることによるのではないかと推測される.5 付着の状態や摂餌方法により,付着生物を第1次付着生物(固着,懸濁物を餌料とする),第2次付着生物(基盤上を動き,付着ヌタを餌料とする)の二に分けた. 6 付着生物の生態学的研究で,環境調査では餌となる懸濁物の性質の調査も必要である.また付着生物群集の性格を明らかにするために,各生物種を付着の仕方,形態,摂餌方法,死後の状態等で整理することが必要であると考える.

著者

山田 鉄雄

出版者

長崎大学水産学部

雑誌

長崎大学水産学部研究報告 (ISSN:05471427)

巻号頁・発行日

no.30, pp.31-34, 1970-12

---

On the night of 26 April 1970, the small purse seiner Fuji-Maru unexpectedly fished about 43 tons of ribbon fish Trichiurus lepturus LINNE at Tachibana Bay, but next night the catch was very poor probably because they dispersed widely throughout the bay. The records of fish-finder are displayed in Figs. 1-5. Special attention may be drawn to the concentrated gathering of ribbon fish in the middle layer of water under the light of fish lamp. The author also mentioned the topographical features of the bottom of the bay, and considered that they are related to fish migration.1970年4月26日夜,橘湾内で巾着網でタチウオの思わぬ大量漁獲があった。魚探像では集魚灯下の中層に濃く集っていた。この群は一夜限りで,翌日からはまとまった漁獲はなかった。 橘湾の漁場の特質を把握するために,適当な定点を定めて海洋観測を行なえば,タチウオのみならず多くの出入魚群の移動状況を知ることができるであろう。

著者

李 正根 平山 和次

出版者

長崎大学水産学部

雑誌

長崎大学水産学部研究報告 (ISSN:05471427)

巻号頁・発行日

no.71, pp.p163-168, 1992-03

被引用文献数

1

---

The population growth of Noctiluca scintillans was investigated, using Tetraselmis tetrathelle as food, at salinities ranging from 8.5-34‰, food levels from 1×10³-8×10⁵ cells/ml and temperatues from 5-32℃. Under every experimental condition, ten to twenty Noctiluca were grown individually in 1 or 3ml of food suspensions for three to four days. The specific growth rates were obtained from the linear regression analysis of the population growth. Salinity: The specific growth rate was maximal at approximately 22‰, and decreased differentially with increasing or decreasing salinities. The lowest salinity for the minimal and continual growth was 14‰, but the sudden drop from 34‰ to 14‰ was lethal. Food Level: There was little growth at the food levels lower than 3×10⁴ cells/ml. At food levels between 3×10⁴ and 3×10⁵ cells/ml, the specific growth rate increased proportionally with increasing food levels. With further increases in food level, the rate increased asymptotically. The values of the specific growth rates were 0.03 (S. D; 0.16) at 3×104 cells/ml, 0.74 (S. D; 0.16) at 3×10⁵ cells/ml and 0.81 (S. D; 0.12) at 8×10⁵ cells/ml. Temperature: The specific growth rate was maximal around 23℃, and decreased differentially with increasing or decreasing temperatures. All Noctiluca died at 32℃ within a day. It grew at 5℃ normally but slowly.

著者

小妻 勝 梅園 茂

出版者

長崎大学水産学部

雑誌

長崎大学水産学部研究報告 (ISSN:05471427)

巻号頁・発行日

no.47, pp.p75-81, 1979-08

---

The training vessels Kakuyo-maru and Nagasaki-maru of the Faculty of Fisheries, Nagasaki University make training trips mainly to the East China Sea and the equatorial waters of the Pacific and Indian Oceans. It often occurred that the vessel could not keep in communication by wireless with home or with other vessels for scores of minutes to several hours because of rain noises, radio interference caused by rain drops. Expecially in the equatorial waters, communication by wireless frequently became completely impossible whenever a squall passed over or near the vessel. The present authors carried out a joint-study on the methods of eliminating rain noises aboard Kakuyo-maru and Nagasaki-maru during the past three years starting from 1976, and almost succeded in it. Rain noises could be eliminated, or reduced to a level at which no incovenience was caused, by blanking the signal flow line at the anterior part of the narrow band pass filter of the intermediate frequency amplifier of the receiver for a short time while pulses of rain noises were being emitted. Heretofore, vessels sailing or operating in the equatorial waters suffered without fail from radio interference. From the results of the present experiments, it is suggested that the attachment of a noise blanker circuit to a commercial radio receiver will ensure a smooth communication and the safety of navigation.これまで赤道周辺を航行する船舶は,必ず雨雑により受信障害を受けた。この雨雑除去法については,まだ改善の余地は残されているものの,受信機の中間周波増幅段の狭帯域フィルターの前の部分で,雨雑パルスの出ている短い時間だけ信号経路をブランキングすることにより,実用通信に支障ないまでに軽減または除去された。すなわち,今回の実験により商用受信機にNoise Blanker Circuitを附加することで,充分雨雑を除去することができ,その結果,常時円滑な通信が可能となった。

著者

松宮 義晴

出版者

長崎大学水産学部

雑誌

長崎大学水産学部研究報告 (ISSN:05471427)

巻号頁・発行日

no.54, pp.p1-11, 1983-02

被引用文献数

1

---

In order to analyze the results of selective fishing on demersal fishes in the East China and Yellow Seas, the effectiveness of effort was calculated from the catch and effort statistics by species and boat sizes. The yearly variation in the effectiveness of effort from 1952 to 1975 showed that yellow croaker and cuttlefishes had a decreasing and increasing tendency respectively, after 1965. In 1977, the material for subsidiary articles of diet (flatfishes, korai prawn, cuttlefishes and yellow sea bream) had a high value in the effectiveness of effort. The raw material for fish paste products (yellow croaker, hairtail, white croaker and lizardfishes) had a low value. The former was chosen as the target for the selective fishing. The seasonal change in the effectiveness of effort for a large sized boat was greater than that of other size categories, and was quite variable by species. The differences in the effectiveness of effort by tides were examined. During a spring tide, white croaker, flatfishes and lizardfishes had a larger value. The value of korai prawn and yellow croaker was larger during a neap tide.数多くの生物資源を対象としている以西底曳網漁業では価格の高い魚種を狙い,細かな漁場位置の選択や網口の高さの調整などをする選択操業が行われている.近年では漁獲の主対象がつぶし物から総菜物に変化している.ここでは多くの期間別漁区別魚種生物種項目別船型別の漁獲量・努力量統計を用い,値が大きいほど対象魚種を狙って操業していることを意味する努力量の有効度εを計算し,以西底曳網漁業における選択操業の実態を分析した. (1)1952年~1975年の努力量の有効度の経年変化をみると,つぶし物であるキグチは1965年以降急激に低下し,総菜物のイカは逆に上昇している. (2)年ごとの努力量の有効度の季節変化は,1965年まではどの魚種もεの増大の山と盛漁期が一致している傾向がみられた. (3)1977年の船型別資料によると,総菜物であるヒラメ・カレイ,タイショウエビ,イカ,レンコダイの努力量の有効度の値は大きかった.つぶし物であるキグチ,タチウオ,シログチ,エソの値は小さく,特にキグチはどの船型でも最低値であった. (4)1977年の大型船における努力量の有効度の季節変化は大きく,魚種間の差異も顕著である.中型船と小型船は季節変化,魚種間の差異とも小さい. (5)潮の大きさ別の資料(1977年)によると,シログチ,ヒラメ・カレイ,エソは大潮時に,タイショウエビ,キグチは小潮時に選択操業の度合が高まる.レンコダイ,イカ,タチウオは潮の大きさと関係が薄い. (6)農林漁区ごとに計算した努力量の有効度と曳網回数の漁場分布を例示し,選択操業の実態を把握した.1977年1月中旬の大型船はタイショウエビ,中型船はイカを,7月下旬~8月上旬の大型船はキグチ,中型船はエソを狙った選択操業を行っていた.

著者

岡 正雄 白旗 総一郎

出版者

長崎大学水産学部

雑誌

長崎大学水産学部研究報告 (ISSN:05471427)

巻号頁・発行日

no.18, pp.30-40, 1965-02

被引用文献数

1

---

"Koraiebi" Penaeus orientalis KISHINOUYE, from the Yellow Sea was studied especially on the manifestation of maturity of its ovary by the examination of the preparing sections of the ovary. For this purpose, the ovarian eggs were first classified as follows from their morphological characteristics according to the degree in advancement toward ripeness: 1. Early nucleolus stage: The small nucleoli (plasmosomes) lie scattered in the nucleus. 2. Later nucleolus stage: The nucleoli are gathered into one or two bodies of a conspicuously large size. 3. Pre-yolk stage: The nucleoli grow long on the periphery of the nucleus. The ovarian egg is covered with a follicle layer. 4. Primary yolk globule stage: The redivided small nucleoli arrange themselves on the periphery of the nucleus. The cytoplasm is full of yolk globules. 5. Secondary yolk globule stage: The nucleoli are linked in a ring, which then reduces to a sphere. Neutral fat is found in the cytoplasm. 6. Tertiary yolk globule stage: No nucleolus can be found in the nucleus. The nucleus is reduced by the oppression of the yolk globules. 7. Pre-maturation stage: The nucleus disappears, while a water-soluble jelly-like substance appears on the circumference of the cytoplasm. 8. Maturation stage: No sample could be obtained, so the examination is left to a future study. The preparing sections were made of the anterior dorsal part of the ovary -where ovarian eggs developed most rapidly in the whole ovary- which was the part representative of the maturity of the whole ovary. Utilizing those sections, we obtained the average containing ratio of the ovarian eggs at every stage in one oviferous pouch of the ovary. Next, the maturing stages of the ovarian eggs were weighted 1, 2, 3, ……7, respectively and were expressed quantitatively. The weighted average, obtained from the calculation by multiplying these weights by the containing ratios of the respective stages, was represented as the maturity of the ovary. From this expression, the degrees of maturity of the ovary were obtained in order of dates of collection, and the tendency formed by them was extrapolated. The estimated date that the ovary attained to the ripe phase corresponded to the reported actual date of ripeness.1964年,黄海において漁獲されたコウライエビの卵巣切片の標本から卵巣熟度を表現することを試みた. 先づ卵巣卵をその特徴的形態からつぎのように分類した. (1)仁前期:卵径0.1-0.2mm,核内には小仁が散在する. (2)仁後期:卵径0.2-0.3mm,核内には大型仁がみられる. (3)前卵黄期:卵径0.3-0.5mm,仁は核壁にそって伸びる,部厚い卵上覆がみられる. (4)第1次卵黄球期:卵径1.8-2.5mm,小仁が核壁に並び,卵黄小球が細胞質内に充満する. (5)第2次卵黄球期:卵径の変化認められず,仁は環状につながり次第に縮少して球形となる.細胞質内には中性脂肪があらわれる. (6)3次卵黄球期:卵径はかわらない.仁はみられなくなる.核は圧縮され,中性脂肪は細胞質周辺にあつまって塊状となる. (7)前成熟期:卵径の変化は認められない.核は極端に縮少,あるいは消失,細胞質周辺にはゼリー状物質が充塡されている空胞がみられる. 成熟期卵(8)については標本の入手が出来なかった. 卵巣の各部分における成熟の違いをしらべたところ頭胸部に近い背部が一番速く成熟してゆくことがわかった.しかし,他との違いは卵巣卵で一階級程度の違いしかなく,他の部分はほとんど均一であるので平均的にみるといづれの場所を卵巣熟度として代表してもさしつかえないので背部の前の位置を代表的切片製作位置として定めた. 切片の熟度に関しては卵巣卵を分類順に1,2,………7,8,と重みをつけ切片標本内における卵巣内卵嚢あたりの階級別卵巣卵の含有率に対してそれぞれを加重しこれらの総平均を求めて総括的に表わした. この表現法を用いて経時的に卵巣成熟過程を追跡しそれを外挿すると排卵は5月上旬から中旬におこることが推定されたが実際の報告と一致したのでこの表現法は適切であったといえる.

著者

麻生 幸則 西ノ首 英之

出版者

長崎大学水産学部

雑誌

長崎大学水産学部研究報告 (ISSN:05471427)

巻号頁・発行日

no.28, pp.219-225, 1969-12

---

高度に機械化された荷役装備をもつ商船でも,荷役作業に75%の能力しか発揮出来ないと云われている.魚荷役中には色々な「もたつき」が存在していて,漁船の荷役能力は50%,甚しいのは20%程度になる場合があるそうである.本調査資料から,長崎魚市場における魚揚荷役の「もたつき」については,次のように云えると思う. (1) 艙内氷中の魚(魚箱)の堀出し,ウインチ操作,選別,秤量等によるもたつきがあったが,これらは,人為的で,ある程度の熟練により最少限に食いとめうるけれども,全く取除いてしまうことの出来ないものである。 (2) 平素の整備の不良による機関や荷役機器の故障によるもたつき,小型船に多いと思われるが,日常の心がけによって解決出来ると信ずる。 (3) 自然条件によるもたつき,大型船では左程問題とならないが,50屯以下程度の漁船運搬船第三魚舎岸壁で低潮時揚荷役は困難である。長崎魚市は長崎湾港の最奥地に位するため大潮時天象海象により,所謂アビキ現象を生じ,4米近い干満の差を見せるそうである。このもたつきは不可抗力である.尚,第一魚舎における手繰船揚荷役は7米のスラットコンベアを橋渡しにして接岸するが,傾斜によるスラットコンベアの速度に変化がみられないので,干満による荷役作業に大差はない.

著者

張 国勝 竹村 暘

出版者

長崎大学水産学部

雑誌

長崎大学水産学部研究報告 (ISSN:05471427)

巻号頁・発行日

no.66, pp.p21-30, 1989-10

---

The acoustical behavior of Brown Goby Bathygobius fuscus was studied. The calls consisted of a pulse or a series of pulse sounds and grunt sounds. Those calls were lower in frequency and weak in power, because they had not special sound productive mechanism and any amplifier like swimbladder. Then, the effective area of pulse sound was limited in less than several ten centimetres in diameter and that of grunt sound was still smaller. The frequency of pulse sound emitting became high about sunrise and sunset, however, any remarkable tendency in diurnal change was not observed in grunt sound. They usually used the pulse sound for threat and grunt sound for courtship. Then, the pulse sound were heard through the year laying stress on July and August. On the other hand, the grunt sounds were heard only in reproductive season (June through September).