Nest Site Selection and Factors Affecting Hatching Success of Common Moorhens (Gallinula chloropus) at Yu-gu stream, South Korea

Jin-Woo Jung,Jin-Hee Yi,Kwang-Seok Youm,Chung-Yeol Baek,Sam-Rae Cho 한국조류학회II 2015 한국조류학회지 Vol.22 No.1

The purpose of this study was to examine the factors affecting common moorhens’ nest site selection and hatching success in Yugu stream, Gongju-si, South Korea. Common moorhens’ nests were found in colonies of Phragmites japonica, Iris pseudoacorus, and Typha angustata; of these, Typha angustata colony turned out to be the most preferred (82.1%). The hatching failure factors of common moorhens were found to be predation (55.6%), flooding (38.9%), and destruction by fishermen (5.6%). The factors affecting common moorhens’ nest site selection turned out to be water depth, vegetation height, distance to open water, and vegetation density. It was found that, with the decrease of water depth and vegetation height, the possibility of nest creation increased; furthermore, with the increase of distance to open water and vegetation density, the possibility of nest creation increased. Except for the nest height, there was no significant difference in the nest site characteristics between breeding nests and trial nests. Nest height of the breeding nest sites was significantly higher than that of the trial nest sites. With the increase of vegetation height, distance to the bank, and nest height, the possibility of breeding nests increased. Successful hatching nests had a significantly higher vegetation density and nest height than failed hatching nests. Vegetation density turned out to affect common moorhens’ hatching success. It seems that, with the increase of vegetation density, common moorhens can more easily hide from predators and thus stay safe.

Egg Production Rate of the Copepod Calanus sinicus off the Korean Coast of the Yellow Sea during Spring

강형구,이창래,최근형 한국해양과학기술원 2011 Ocean science journal Vol.46 No.3

The egg production rate (EPR) of Calanus sinicus was measured from March 2007 to April 2010 at three stations along the Korean coast of the Yellow Sea (in coastal waters off Saemangum, Yeongheungdo, and Asan Bay) to estimate in situ maximum egg production rate (MEPR) and to understand whether the females were limited in their growth or fecundity in the field. The mean EPR of C. sinicus at each sampling date ranged from 10.3-34.9 eggs female^(-1) d^(-1) (mean 23.4 eggs female^(-1) d^(-1)), and the EPR of individual copepods ranged from 0-81 eggs female^(-1) d^(-1). The mean EPR was positively correlated with the body weight of female copepods. The MEPR at each sampling date ranged from 40-81 eggs female^(-1) d^(-1) (mean 50.4eggs female^(-1) d^(-1)). Over 84% of eggs spawned hatched successfully. The weight-specific growth rate (WSGR) ranged from 0.038-0.111 d^(-1) (mean 0.082 d^(-1)), indicating that 3.8-11.1% of the carbon in an adult female was produced daily as female growth. The WSGR was negatively correlated with water temperature. The ratio of mean EPR to observed mean MEPR ranged from 20-70% (mean 46%), indicating that ~54% of a female’s growth might be limited in the field. We suggest that the ratio of observed EPR to mean MEPR of copepod can be applied to understand how the copepod responds to environmental changes, as well as EPR and hatching success.

Nesting Site Preference and Hatching Success of the Kentish Plover (Charadrius alexandrinus) in the Nakdong Estuary, Busan, Republic of Korea

홍순복,Seigo Higashi 한국생태학회 2008 Journal of Ecology and Environment Vol.31 No.3

This study was conducted to determine clutch size and habitat usage of Kentish plovers (Charadrius alexandrinus) breeding on Sinja-do Islet in the Nakdong Estuary from 22 April to 12 July in 1995 and from 21 April to 20 June in 1996. The Kentish plover preferred grasslands and damp sands to dry dunes as nesting sites. The difference in hatching success among these microhabitats was attributed to high tides, which washed away many nests on damp sands, and strong winds, which frequently shifted the sand to bury eggs on dry dunes. The main mortality factor in grasslands was predation by magpies Pica pica. Each clutch contained one to four eggs, with a mode of three eggs. Hatching success was highest in two-egg clutches and lowest in one- and four-egg clutches. The mean interval for egg laying was 1.8 days between the first and second eggs and 2.1 days between the second and third eggs. The average incubation period was about 24.2 days. This study was conducted to determine clutch size and habitat usage of Kentish plovers (Charadrius alexandrinus) breeding on Sinja-do Islet in the Nakdong Estuary from 22 April to 12 July in 1995 and from 21 April to 20 June in 1996. The Kentish plover preferred grasslands and damp sands to dry dunes as nesting sites. The difference in hatching success among these microhabitats was attributed to high tides, which washed away many nests on damp sands, and strong winds, which frequently shifted the sand to bury eggs on dry dunes. The main mortality factor in grasslands was predation by magpies Pica pica. Each clutch contained one to four eggs, with a mode of three eggs. Hatching success was highest in two-egg clutches and lowest in one- and four-egg clutches. The mean interval for egg laying was 1.8 days between the first and second eggs and 2.1 days between the second and third eggs. The average incubation period was about 24.2 days.

Effects of Acute Acid Stress on Hatching and Mortality of Hermaphroditic Teleost, Rivulus marmoratus(Cyprinodontiformes; Rivulidae)

Kim, Ae-Ri,Lee, Meoung-Sook,Park, Eun-Ho The Korean Society for Integrative Biology 2003 Korean journal of biological sciences Vol.7 No.4

The effects of acute acid stress on hatching success and hatching period of laboratory-reared hermaphroditic fish Rivulus marmoratus were examined. The effects of acute acid toxicity on mortality was also determined in three life stages of this fish. There was a significant negative effect of acid stress on hatching performance in the R. marmoratus embryos. The hatching success was only 5% at pH 3.5 compared to over 78% at pH higher than 4.0. The hatching period was also delayed by low pH treatments. The larval and juvenile stages were more sensitive to acid toxicity on mortality than the adult stage, but larvae and juveniles showed similar sensitivity. The 96-h LC50 value was pH 3.8 in larval and juvenile stages and pH 3.3 in adult stage.

낙동강하구에서 쇠제비갈매기의 번식 상황의 변화

이인섭(In-Sup Lee),홍순복(Soon-Bok Hong) 한국생명과학회 2009 생명과학회지 Vol.19 No.11

본 연구는 1990년대 중?후반기(1995년, 1996년, 1998년)와 2000년대 중반기(2004년, 2005년)에 조사한 쇠제비갈매기의 번식에 관한 자료를 분석하여 낙동강 하구의 최남단에 위치하고 있는 신자도와 도요등에서의 쇠제비갈매기(Little Tern Sterna albifrons)의 번식 상황의 변화를 알아보고자 수행하였다. 신자도에서는 1995년에 쇠제비갈매기의 둥지 638개를 조사하였는데, 한배 산란 수는 평균 2.48개이었고, 1996년에는 총 106 둥지를 조사하였는데, 한배 산란 수는 2.35개이었으며, 2004년에는 총 94 둥지를 조사하였는데 한배 산란 수는 평균 2.16개이었다. 2005년에는 총 456 둥지를 조사하였는데 한배산란 수는 평균 2.53개 이었고, 4년간의 한배 산란 수에는 통계적으로 유의한 차이가 있었다(p<0.001). 도요등에서는 1998년에 총 263 둥지를 조사하였고 한배 산란 수는 평균 2.18개이 었고, 2004년에는 총 1,023 둥지를 조사하였는데 한배 산란수는 평균 2.33개이었으며, 2005년에는 총 1,123 둥지를 조사하였는데 한배 산란 수는 평균 2.52개 이었다. 3년간의 한배 산란수에는 통계적으로 유의한 차이가 있었다(p<0.001). 신자도에서의 쇠제비갈매기의 부화 성공률은 54.5%이었으며, D형 둥지와 A형 둥지에서 높았고 C형 둥지에서 낮았다. 부화 실패 요인으로서는 범람이 가장 큰 요인이었으며 특히 C형 둥지에서 그러하였다. 도요등에서의 부화 성공률은 73.2%이었으며, D형 둥지와 A형 둥지에서 높았고 C형 둥지에서 낮았다. 부화 실패요인으로서는 범람이 가장 큰 요인이었으며 특히 C형 둥지에서의 영향이 컸다. 낙동강 하구의 사주는 앞으로도 많은 변화가 예상되지만, 쇠제비갈매기 등의 번식지로서의 기능을 다하기 위해서는 포식자의 퇴치와 사주의 육화 방지와 모래가 있는 나대지를 유지하기 위하여 갈대제거 등 지속적인 관리가 절실히 요구된다. This study was conducted to determine the characteristics in breeding of the little tern Sterna albifrons in Shinja-do and Doyo-Deung in Nakdong estuary. The data was obtained in the middle and late 1990‘s and in the mid 2000's, which were analysed for the breeding information of the little tern. In Shinja-Do, a total of 638 nests were observed in 1995, and the average numbers of eggs laid per nest were 2.48. In 2004 and 2005, 94 and 456 nests were observed, and the average number of eggs laid per nest was 2.16 and 2.53, respectively. There was a significant difference between the average numbers of eggs laid per nest for the 3 respective years. In Doyo-Deung, a total of 269 nests were observed in 1998, and the average number of eggs laid per nest was 2.16. In 2004 and 2005, 1,023 and 1,123 nests were observed, and the average numbers of eggs laid per nest were 2.33 and 2.52, respectively. There was a significant difference (p<0.001) between the average number of eggs laid per nest as well. Hatching success rate by nesting site in Shinja-Do was calculated in 1995. Type A nest (nest located on dry sand land) showed a 56.8% success rate, and type B nest (nest located on the land with dwarf grass), type C nest (nest located on moist land) and type D nest (nest located on the land with shells) showed 55.3%, 36.6% and 59.3% success rates, respectively. The average hatching success rate in Shinja-Do was 54.5%. The most crucial factor for hatching failure was flood, especially, for the type C nests. The hatching success rate by the nesting site in Doyo-Deung showed an average of 73.2%. It was high in type D nest (83.8%) and type A nest (75.9%), and low in type C nest (59.7%). Again, the most crucial factor for hatching failure was flood, especially, for the type C nests. Nakdong estuary has been through many changes over time, particularly in recent. Therefore, continuous efforts to keep it a breeding place for the little tern are urgently required, including overall management of land, protection of reef and sand, etc.

Low breeding success of the little egret (Egretta garzetta) near residential areas and in colonies exposed to gales: a comparison of colony in Sichuan, Southwest China, with literature

Rui Hua Pang,Tong Lei Yu,Michael Busam 한국통합생물학회 2019 Animal cells and systems Vol.23 No.3

The breeding biology of the little egret (Egretta garzetta) was studied in 20 nests within the mixed-species breeding colonies at Nanchong, Sichuan, Southwest China, in 2006. By measuring a set of physical characteristics of vegetation at the nests and at a set of 20 randomly chosen sites we showed that birds preferentially used taller trees in areas with fewer shrubs of higher species diversity. Nests at lower locations in trees had marginally lower hatching success due to their destruction by humans; this destruction contributed marginally significantly to lowering of the total nesting success in all studied nests. Although gale winds also had a negative effect on breeding success, the anthropogenic influences were a greater factor in reproductive failure. We found similar effects in our review of literature on breeding success of the little egret from various geographical areas. Our results may be of use by conservation organizations in their actions to protect colonies of the little egret.

Effect of Temperature on the Hatching Success of Asian Gpysy Moth, Lymantria dispar (Linne) (Lepidoptera: Lymantriidae)

Kwang-Su Lee,Dong-Pyo Lyu,Chang-Ki Hong,Chuleui Jung,Ki-Jeong Hong,Young-Ju Park,Heung-Sik Lee 한국응용곤충학회 2012 한국응용곤충학회 학술대회논문집 Vol.2012 No.10

This study was conducted to estimate temperature effect on the hatching success of Asian Gypsy Moth (AGM), Lymantria dispar (Linne) in different temperature conditions (15, 20, 25, 30, and 35℃). The egg masses were collected during winter season and stored in cold room (4℃). The hatching rate was evaluated from the number of hatched caterpillar for period of 50 days. As a result, hatching rates were 89.80, 92.94, 95.51, 62.02, and 18.35% at 15, 20, 25, 30, and 35℃, respectively. The optimal temperature on the hatching success of AGM egg might be 20~25℃.

긴꼬리딱새 Terpsiphone atrocaudata의 번식생태에 대한 연구

김영호(Young-Ho Kim),김완병(Wan-Byung Kim),오홍식(Hong-Shik Oh) 한국조류학회II 2011 한국조류학회지 Vol.18 No.4

제주도에서 번식하는 긴꼬리딱새의 번식생태를 밝히기 위하여 2008년부터 2010년 번식기간 중 고정조사구 5곳을 선정하여 조사하였다. 연구결과, 한배 산란수는 2-4개였고, 평균 3.3개의 알을 낳는 것으로 나타났다. 부화성공률은 알이 4개인 둥지는 29%, 3개인 둥지는 67% 그리고 2개인 둥지는 100%인 것으로 나타났다. 이소성공률은 4개의 알이 100%, 3개의 알 50% 그리고 2개의 알이 100%로 나타나 2개의 알이 이소성공률이 높은 것으로 나타났다. 번식성공률은 4개의 알이 29%, 3개의 알 33% 그리고 2개의 알이 100%로 나타나 2개의 알이 이소성공률이 높은 것으로 나타났다. 알의 평균 크기는 장경 20.56±0.11mm, 단경 15.61±0.86mm 그리고 무게는 2.80±0.40g이었다. 유조의 부리, 부척, 체중은 비교적 고른 성장곡선을 나타내었으나, 날개와 꼬리는 급속한 성장 곡선을 보였다. 포란은 암컷이 수컷보다 많은 시간을 투자한다는 것이 확인되었다. Breeding ecology of Black Paradise Flycatcher (Terpsiphone atrocaudata) was studied at five areas on Jeju, Korea from 2008 to 2010. The Black Paradise Flycatcher laid 2 to 4 eggs with an average of 3.3 eggs per clutch. The hatching success rate was 29% for a clutch of 4 eggs, 67% for a clutch of 3 eggs, and 100% for a clutch of 2 eggs. The fledgling success rate was 100% for a clutch of 4 eggs, 50% for a clutch of 3 eggs, and 100% for a clutch of 2 eggs. The breeding success rate was 29% for a clutch of 4 eggs, 33% for a clutch of 3 eggs, and 100% for a clutch of 2 eggs. The average size of eggs was as follows: major axis 20.56±0.11mm, minor axis 15.61±0.86mm, and weight 2.80±0.40g. The bill, tarsus, and weight of chicks grew relatively slowly, but the wings and tail grew fast. The time spent for incubating by female was longer than that by male.

수리부엉이의 교미행동에 관한 연구

신동만,백운기 한국환경생태학회 2008 한국환경생태학회지 Vol.22 No.1

본 연구는 2005년부터 2007년까지 파주, 강화도, 이천, 시화호, 충주 등 5개 지역에 서식하는 수리부엉이 9개 쌍의 둥지를 정기적으로 촬영, 관찰하여 번식생태와 교미행동을 연구하였다. 한배산란수는 1~4개로 평균 2.77개(n=15)였으며, 부화성공률은 약 71%(n=34)였고, 이소성공률은 약 83%(n=23)였다. 수리부엉이는 산란이 끝난 후에도 암수간의 교미행동이 지속되며, 새끼들이 둥지를 떠나는 시기인 부화 후 7~8주까지 교미행동을 계속한다는 것을 확인하였다. 이러한 수정 목적 이외의 교미 행동은 암컷과 수컷 모두의 필요에 의해서 이루어지는 것으로써 ‘부부관계(pair-bond)’의 확인, 유지, 강화를 통해 새끼를 안정적으로 키우기 위한 것으로 해석된다. This study is mainly focused on the mating of 9 couples of Eagle Owl Bubo bubo habitating in Paju, Ganghwa Island, Icheon, Sihwa Lake, Chungju. For this study, from 2005 to 2007, regular filming and mornitoring for the breeding ecology and copulation behavior of 9 couples of Eagle Owl in the nest and near area had been done. Clutches ranged in size from one to four eggs but averaged 2.27 eggs(n=15), hatching success rate was 71%(n=34) and fledgling success rate was 83%(n=23). Through the filming and mornitoring, it was found that Eagle Owl continued to copulate each other even after hatching and kept its copulation until the chicks left their nest(7~8 weeks after hatching). This copulation behaviour without fertilization seems to be done for confirming, maintaining and strengthening of pair-bond by the necessity of both male and female, and to aim at stable breeding of their chicks.

Effects of temperature and salinity on egg development and larval settlement of an invasive ascidian species, Herdmania momus (Savigny, 1816)

Park, Juun,Lee, Yun-Sik,Kim, Donghyun,Shin, Sook Korean Society of Environmental Biology 2020 환경생물 : 환경생물학회지 Vol.38 No.4

The effects of temperature and salinity on egg development and settlement of the ascidian Herdmania momus were investigated. Adult specimens were collected from the Dodu Yacht facility in Jeju Island, Korea(33°30'30.54"N, 126°27'55.46"E) in August 2018. Egg development and larval settlement were observed and recorded at 8 h intervals using a stereomicroscope, under nine temperature (10, 13, 16, 19, 22, 25, 28, 31, and 34℃), and four salinity regimens (28, 30, 32, and 34 psu). The highest hatching rate (82.8±7%) was observed at 32 psu and 25℃ and the lowest hatching rate (1.0±2%) was at 34 psu and 13℃. The developmental rate (0.222±0.0994) was highest at 28 psu and 28℃, and lowest (0.016±0.008) at 30 psu and 13℃. The highest settlement success rate (77.1±5%) was at 32psu and 25℃ and the lowest(0.1±1.0%) was at 30psu, and 13℃. The rate of settlement(0.080±0.000) was highest at 28psu and 28℃, and lowest(0.013±0.000) at 30psu and 13℃. Both hatching and settlement success rates increased as temperature increased and tended to decrease beyond an optimal temperature range. Herdmania momus preferred 30-34 psu salinity and 22-25℃ temperature. This study provides baseline information about the life history of H. momus, and important data to control the damage caused by the increase in number and distribution of this invasive ascidian.