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Nest site tenacity and mate fidelity in the Black-headed Gull(Chroicocephalus ridibundus)
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作者 Simon Piro Angela Schmitz Ornés 《Avian Research》 SCIE CSCD 2021年第4期664-670,共7页
Breeding philopatry is well known in the Black-headed Gull(Chroicocephalus ridibundus).Using a capture-markrecapture method,we studied if Black-headed Gulls show nest site tenacity and mate fidelity as well,and invest... Breeding philopatry is well known in the Black-headed Gull(Chroicocephalus ridibundus).Using a capture-markrecapture method,we studied if Black-headed Gulls show nest site tenacity and mate fidelity as well,and investigated if there are differences between a stable,and a newly established and fast-growing colony,as well as for differences between the center and edges of these colonies located in north-eastern Germany.We found a high level of nest site tenacity in the center of the stable colony on B?hmke Island,and lower degrees of nest site tenacity at the edge of the same colony and in the newly established and fast-growing colony on Riether Werder.Mate fidelity was very strong in all individuals which returned to their previous breeding place,regardless of the nest site location. 展开更多
关键词 black-headed Gull Croicocephalus ridibundus Mate fidelity Nest site tenacity PHILOPATRY
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Study on Breeding Practices and Reproductive Performance of Black-Head Somali Sheep under Traditional Management System: The Case of Awbarre District, Eastern Ethiopia
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作者 Abdi Abdilahi Kawnin Abdimahad +1 位作者 Abdulahi Mahamed Abdimawlid Ali 《Open Journal of Animal Sciences》 CAS 2023年第1期20-33,共14页
The study was conducted in the Awbarre district of the Fafen zone of the Somali regional state of Ethiopia. The objective of the study was to assess the breeding practices and reproductive performance of Black-head So... The study was conducted in the Awbarre district of the Fafen zone of the Somali regional state of Ethiopia. The objective of the study was to assess the breeding practices and reproductive performance of Black-head Somali sheep under a traditional management system. Purposive and simple random sampling techniques were used to select targeted kebeles and households, respectively. A total of 120 households were selected from four kebeles, each of 30 households, based on the production system and sheep population. Semi-structured questionnaires, group discussions, key informants interviews and field observations were used to generate the required data. The primary purpose of keeping sheep was for income generation, followed by saving as a future asset. The majority (89.2%) of the respondents separated male and female animals during herding. The selection criteria for breeding rams were appearance, growth, pedigree, and color while for breeding ewes were appearance, adaptability, pedigree, color, and lamb growth. The overall weaning age of Black-head Somali sheep in the study area was 3.7 months for both males & females. The castration of male sheep was common for the purpose of fattening, fattening with breeding control and breeding control as well. The castration is mainly performed during the summer and autumn and the methods of castration were both traditional and modern methods, the traditional castration method being the most important one in pastoral areas. The age of sexual maturity was 7.64 months for rams and 8.97 months for ewe’s male and female lambs in the pastoral area and 8.42 & 8.38 for rams & ewes in agro-pastoral and overall lambing interval was 11 months. On average, the ewe of Black-head Somali sheep in pastoral & agro-pastoral could produce 9.49 & 9.57 lambs, respectively in their lifetime. As the pastoralists and agro-pastoralists indicated the source of the breeding ram was their own, so the exchange of breeding ram is recommended to minimize the risk of inbreeding and further studies of on-farm performance investigation would be necessary to be carried out so as to understand the uniqueness of the breed better. 展开更多
关键词 black-head Somali Sheep Breeding Practice Reproductive Performance Selection Criteria
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Distribution and Status of the Pallas’s Gull Ichthyaetus ichthyaetus(Pallas,1773)in the Reservoirs of the Palearctic:Review
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作者 Sergey Vladimirovich Golubev 《Research in Ecology》 2023年第1期23-34,共12页
The Pallas’s Gull Ichthyaetus ichthyaetus is a piscivorous gull,some local populations of which are rare and vulnerable.The review presents data on the status and distribution of the Pallas’s Gull in the reservoirs ... The Pallas’s Gull Ichthyaetus ichthyaetus is a piscivorous gull,some local populations of which are rare and vulnerable.The review presents data on the status and distribution of the Pallas’s Gull in the reservoirs of the Palearctic-water bodies in which the water level is controlled by humans.The aim of the study was to assess the current state of the species in the reservoirs of the Palearctic.The review was based on 1080 publications found in the search engines Yandex,Google,Google Scholar,eLybrary.During the last 35 years,the Pallas’s Gull has been found in 63 reservoirs of the Palearctic.Breeding has been established in 11 reservoirs,breeding has not been established in 43 reservoirs,and birds were present in 9 reservoirs,but the status was not specified.Two-thirds of the reservoirs where the gull was recorded or bred were located in the European part and only 1/3 in Asia.It is assumed that up to 5000 adults(0.45%-4.0%of the global population of the species)breed annually in the reservoirs of the Palearctic,and the reservoirs are not the main habitats for maintaining and reproducing the population of the species.The majority of the breeding population reproduces in natural water bodies,and the reservoirs of the Palearctic are important for the maintenance of non-breeding individuals.Detection of presumed breeding and new breeding colonies in reservoirs north of the historical range of the species has been established on the Russian Plain,in the Urals and Trans-Urals.The reservoirs of Russia play a leading role in providing breeding sites for the species in water bodies of this type.An analysis of the data allows us to state the important and increased role of reservoirs in the modern distribution and expansion of the range of the Pallas’s Gull in the Palearctic. 展开更多
关键词 Great black-headed Gull Damming
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Production protocol for and storage efficacy of an anthocorid predator Cardiastethus exiguus Poppius 被引量:1
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作者 BALLAL Chandish R. 《环境昆虫学报》 CSCD 北大核心 2012年第1期50-56,共7页
Cardiastethus exiguus Poppius is an indigenous anthocorid predator of eggs and neonates of the notorious pest,coconut black-headed caterpillar Opisina arenosella Walker in India.At the National Bureau of Agriculturall... Cardiastethus exiguus Poppius is an indigenous anthocorid predator of eggs and neonates of the notorious pest,coconut black-headed caterpillar Opisina arenosella Walker in India.At the National Bureau of Agriculturally Important Insects(Indian Council of Agricultural Research),Bangalore,India,a simple mass production protocol was developed for multiplying C.exiguus using UV-irradiated eggs of alternate laboratory host Corcyra cephalonica Stainton.Field evaluation of the predator in the states of Kerala and Karnataka indicated that this predator could bring about a significant reduction in the pest population.Subsequently,the need was felt to investigate the storage efficacy of the eggs and adults of C.exiguus so that sufficient numbers could be accumulated and transportation of the predator could be planned for field releases.Low temperature storage studies indicated that C.exiguus eggs can be safely stored for up to 5 days at 10℃ and 10 days at 15℃ and incubation period could be staggered for up to 10 and 13 days,respectively.The longevity of the C.exiguus adults was significantly reduced due to low temperature storage.However,for adult females,a storage temperature of 15℃ for 15 days could be recommended as they could live for a more than a month after removal from storage and their progeny production was comparable to that of the control adults. 展开更多
关键词 ANTHOCORIDAE Cardiastethus exiguus coconut black-headed caterpillar Opisina arenosella production protocol STORAGE
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