• 한국어류학회지
• /
• 제29권4호
• /
• pp.261-266
• /
• 2017

모래주사 Microphsygobio koreensis는 환경부에 의해 멸종 위기종으로 보호받고 있는 한국 고유종이다. 본 연구에서 모래주사의 산란시기와 특성에 대한 조사를 통해 종 보존을 위한 기초자료를 얻고자 하였다. 조사는 2011년 4월부터 2012년 10월까지 전북 임실군 신평면 덕암리에서 실시하였다. 자연 상태와 조직학적 관찰을 통해 산란시기는 4~5월로 산란 성기는 수온이 $20{\sim}23^{\circ}C$인 5월초로 확인되었다. 산란시기의 수컷은 몸 전체가 밝은 주황색을 띄고 아가미 뒷부분에서부터 미병부까지 이어지는 중앙 줄무늬와 가슴지느러미 그리고 배지느러미가 붉어지는 특징을 보였고 추성은 나타나지 않았다. 반면 암컷은 몸 전체가 어두운 갈색을 가졌다. 난소 내 포란수는 10,705~22,165 ($15,573{\pm}4,274$)개였고 성숙난의 수는 1,100~5,920 ($3,383{\pm}2,126$)개로 나타났으며 성숙난의 비율은 10.3~44.8 ($22.4{\pm}15.6$)%였다. 그리고 성숙난의 크기는 $0.74{\pm}0.06$ (0.60~1.00) mm였다.

• 한국어류학회지
• /
• 제28권2호
• /
• pp.93-99
• /
• 2016

본 연구는 2008년 11월부터 2009년 10월까지 경상남도 의령군 유곡면 세간교 일대 유곡천에서 수수미꾸리의 산란시기와 산란특성에 대해 조사하였다. 수수미꾸리의 연령을 분석한 결과 수컷은 1년생 전장 45~55 mm, 2년생 55~75 mm, 3년생 75 mm 이상, 암컷은 1년생 40~55 mm, 2년생 55~75 mm, 3년생 75~95 mm, 4년생 95 mm 이상으로 추정되었다 (2009년 1월 기준). 산란시기는 5~6월 사이로 추정되었고 (수온 $21.0{\sim}26.6^{\circ}C$) 성적으로 성숙하는 연령은 만 2년생 이상으로 판단되었으며 포란수는 202~747개 ($491{\pm}154.0$)로 나타났다.

• 환경생물
• /
• 제25권4호
• /
• pp.370-377
• /
• 2007

납자루아과의 어류들과 산란습성이 유사한 중고기 Sarcocheilichtys nigripinis morii의 산란생숙주 선택성과 초기 생활사에서 나타나는 배와 자어의 적응 형질을 조사하였다. 중고기의 수정난은 조사수역에 동소적으로 서식하는 담수산 이매패들 중에서도 엷은재첩과 재첩의 체내에서만 관찰되어 숙주 특이성을 보였다. 산란되는 부위는 이매패의 외투강으로 수정난의 난막이 2배 정도로 크게 팽창하며, 부화 전 기관 형성이 완성되어 운동이 자유로운 eleutheroembyo 상태로 발달하는 점 등은 납자루아과와 차이를 보이는 생식전략으로 사료되었다. 그러나 자어기 난황 표면의 호흡 혈관이 크게 발달하는 점은 체내 기생에 따른 보상 형질로 판단되었다. 흑색소포의 발달은 느린 편으로 하미축골 부위에 발생하는 흑색반점은 본 종의 자어를 구분하는 특징이 될 것으로 사료되었다.

• 한국환경과학회지
• /
• 제31권10호
• /
• pp.861-868
• /
• 2022

The Namdae stream in Gangneung-si is one of the rivers where salmon stock is mainly maintained by natural spawning rather than artificial seedlings. There are structures including weir, and fish distribution and movement characteristics can be different by these structures. In this study, we investigated the distribution and behavioral characteristics of salmon by sighting survey within 12 km immediately upstream of the river mouth between October 2021 and February 2022. As a result, salmon distributed within 9 km from rivermouth. There were more salmon in the lower reaches of Doosan weir than in the upper reaches of that. The main spawning ground for salmon was between 7-9 km from rivermouth and around the lower part of Doosan weir. Salmon behaved for spawning in the gravel-bed area and undercut slope of the mainstream, such as mating, digging the riverbed, and competition among males. Salmon moved more slowly in the gravel-bed area than sand-bed area. Doosan weir hinders the spawning migration of salmon by frequent flow changes and terraced fishway. This study provides primary information to understand the ecological changes of salmon by environmental changes in the Namdae stream.

• 한국수산과학회지
• /
• 제54권3호
• /
• pp.318-328
• /
• 2021

We investigated the maturity and spawning of the brown sole Pseudopleuronectes herzensteini, in the coastal waters of the East Sea off Gangwon and Gyeongbuk, South Korea, using samples collected by gill net and longline fishery from January 2018 to December 2019. We analyzed oocyte development, monthly maturity stage, gonadosomatic index (GSI) and total length at maturity. Histological analysis of ovarian development in P. herzensteini revealed that the development was group-synchronous. The spawning peak in Gangwon and Gyeongbuk occurred from April to May and from February to March, respectively. Thus, the spawning season in Gangwon was 1-2 months later than that in Gyeongbuk. The length at 50% maturity for females was estimated as 24.2 cm and 19.0 cm in Gangwon and Gyeongbuk, respectively. Similarly, the length at 50% maturity for males was estimated as 19.8 cm and 16.5 cm in Gangwon and Gyeongbuk, respectively.

• 한국발생생물학회지:발생과생식
• /
• 제23권4호
• /
• pp.323-331
• /
• 2019

In this study, an experiment was conducted to investigate the annual reproductive cycle of a Korean flat bittering, Acheilognathus rhombeus, from Ogok-myeon located in Seomjin River. The reproductive cycle was examined histologically regarding water temperature and day length of the habitat, the gonadosomatic index (GSI), and developmental characteristics of female and male gonads. The maximum GSI was found to be 3.50±0.53 and 1.36±0.14 for females and males, respectively, when the water temperature and day light was 16.9℃ and 11.3 hours, respectively in October 2018. On the other hand, the minimum GSI was found to be 0.16±0.09 and 0.69±0.15 for males and females in December 2018 and February 2019, respectively. The ovipositor of females appeared from August to November 2018. We compared and calculated the stages of germ cell developmental characteristics in the testis and ovaries to determine the reproductive cycle. According to the result, we classified the female A. rhombeus reproductive cycle into four phases, which are ripe and spawning phase (October), degenerative phase (November to December), growing phase (January to March) and mature phase (April to September). The annual reproductive cycle of male A. rhombeus was categorized into four phases: mature phase (June to October), degenerative phase (November to March), resting phase (April) and growing phase (May). The Korean flat bittering is an autumn-spawner as the main spawning season in October. In male, testicular spermatogonia appeared all year-round, and the ripe and releasing phase, which is characteristics of the spawning season in other fish, did not appear.

• 한국어류학회지
• /
• 제32권1호
• /
• pp.14-20
• /
• 2020

이번 연구는 산란기로 알려진 12월부터 2월까지 경남 진해만과 통영 연안에서 잠수조사를 통해 산란회유하는 청어의 산란기를 명확히 밝히는 데 목적이 있다. 경남 진해만에서 2017년 12월부터 2018년 1월까지 3개의 정점에서 총 18회, 통영 영운리 연안에서는 2017년 12월부터 2018년 2월까지 총 24회 잠수조사를 통해 결과를 분석하였다. 조사기간 중 확인된 청어 수정란은 진해만 저도 연안에서 평균 740,274개/㎡, 진해만 구산면 연안에서는 평균 671,718개/㎡였다. 통영 영운리 연안에서는 2017년 12월 30일에 388,444개/㎡개의 수정란이 1회 관찰되었고 그 이후 조사에서는 관찰되지 않았다. 이번 연구결과 경남 진해만과 통영 연안에서 청어 산란은 12월 말에 시작되고 이때의 수온은 평균 7.7℃였다.

• 한국수산과학회지
• /
• 제46권6호
• /
• pp.835-842
• /
• 2013

Flathead flounder Hippoglossoides dubius is a commercially important fish in the coastal waters of Gangwon Province, which is its spawning ground and breeding habitat. A total of 1,669 gonads were sampled monthly from February 2011 to May 2013 to investigate ecological characteristics, such as variations in maturation and spawning by gonad index, visual maturity stage, histological observations and oocyte diameter. Males were numerically dominant over females in the fishing grounds year round. The spawning season was from January to April, and the peak was from February to March. Oocyte number as a measure of fecundity was between 27,372 and 915,209 eggs with a length range of 26.0-48.7 cm TL, while the largest oocyte grew to 0.9-1.4mm in egg diameter during its spawning season. The relationship between fecundity and total length was $F=0.0016TL^{5.2539}$. The smallest mature lengths of the females and males were 28.4 and 22.6 cm respectively, and the 50% mature lengths of females and males were 32.9, 26.9 cm respectively.

• 한국패류학회지
• /
• 제31권2호
• /
• pp.113-121
• /
• 2015

Gametogenesis, mating behaviour and spawning of Octopus ocellatus were investigated by histological study. This species is dioecious, and showed a protandry phenomenon. Ooogenesis (in females) and spermatogenesis (in males) can be classified into 3 stages, respectively. O. ocellatus copulates in one of two ways: a male may leap upon a female, mounting her mantle, or a male may sit near the female and extend the hectocotylized third right arm toward her. Spawning occurred between April and June in females, and between March and May in males of O. ocellatus. The spawning period was once a year and the peak took place between May and June. A number of flatened follicle cells, which were attached to an oocyte, were involved in vitellogenesis in the cytoplasm of the vitellogenic oocyte (maturing oocyte), and formation of chorion membrane (secondary egg membrane) of the ovarian eggs. Fecundity per female closely related to GSI was 294-660 eggs (average, 429 eggs). The diameters of the ovarian eggs surrounded by chorion membrane were approximately in the range of 10.10-2.50 mm. Each ovarian egg laid by a female was connected to an egg string. Each egg string was 1-5.5 cm (average 3.6 cm). The total number of eggs laid by a female of this species ranged 218-314, the egg sizes were independent to the size of female adult. this species has a life mode showing some special reproductive characteristics of an annual semelparity as shown in Octopodidae species because we have never seen a female spawning a second time.

• 한국발생생물학회지:발생과생식
• /
• 제17권3호
• /
• pp.247-255
• /
• 2013

The gonadsomatic index (GSI) of mottled skate was the highest in April, GSI and HSI showed a reverse phase for its reproductive cycle. The fish had one pair of egg capsules, having 1 to 7 fertilized eggs, and spawned all the year round. When surveying the reproductive characteristics of females over 63 cm in disc width, we found the spawning peak was between April to June, and the appearance ratio of egg capsules was the highest in May (32.1%). The eggs were hatched at $8^{\circ}C$, $13^{\circ}C$, $18^{\circ}C$, water temperature (12.8 to $24.2^{\circ}C$), and the best hatching temperature was $18^{\circ}C$. The number of fish hatched was 4 to 5 fish/egg capsules, and the hatching rate was 100%. The sex ratios of hatching larvae were 45.5% female and 54.5% male. Therefore this study will provide fundamental data and information for artificial reproduction of the mottled skate.