• Journal of Ecology and Environment
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• 제32권3호
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• pp.137-143
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• 2009

Pre-dispersal seed predation by a granivorous bird, the masked grosbeak (Eophona personata, Fringillidae), was investigated in two bird-dispersed trees, Celtis sinensis and Aphananthe aspera (Ulmaceae). The objectives of this study were to 1) measure direct damage of predation by grosbeaks on plant crops, 2) reveal the temporal pattern of predation within each tree species and its causal factors, and 3) test whether foraging grosbeaks hinder foraging of frugivorous birds, thereby indirectly impacting the reproduction of both tree species. A substantial amount of fruit and seed crop was consumed by grosbeaks (24.3% in Celtis; 55.5% in Aphananthe), and only 17.7% (Celtis) and 16.7% (Aphananthe) were removed by frugivorous birds. At the study site, the grosbeak population size fluctuated greatly during the fruiting seasons of both plant species. As for Celtis, predated seed density also fluctuated temporally, and the local population size of grosbeaks was responsible for predated seed density. In Aphananthe, predation was not fully explained by grosbeak populations or plant phenology, but its peak coincided with that of grosbeak population. These results suggest that predispersal seed predation by granivorous birds can have large negative impacts on the bird-dispersed plants. Changes in local population size of granivorous birds can influence predatation and can affect reproductive success of the bird-dispersed plants available to the birds.

• 한국산림과학회지
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• 제96권6호
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• pp.633-638
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• 2007

보리밥나무(Elaeagnus macrophylla)는 해안 인접지의 척박한 토양에서 생육하는 상록성 질소고정 식물로서, 열매의 결실기는 조류의 봄철 이동시기와 일치한다. 보리밥나무의 열매를 이용하는 조류를 파악하고 이들이 보리밥나무의 종자 산포와 발아에 미치는 영향을 밝히기 위하여 2007년 3월부터 4월까지 이동성 조류의 중간 기착지인 전남 선안군 홍도에서 조류 조사 및 종자 발아실험을 실시하였다. 그 결과 찌르레기(Sturnus cineraceus), 직박구리(Hypsipetes amaurotis), 개똥지빠귀(Turdus naumanni) 등 8종의 조류가 보리밥나무 열매를 섭식하였으며, 조류에 의해 소화된 종자는 자연 상태로 파종된 열매에 비해 발아시기가 단축되고 발아율도 높아진 것으로 나타났다. 또 열매를 주로 이용한 찌르레기류의 행동권 분석을 통해 보리밥나무 종자의 잠재적인 산포 범위는 6.9 ha에 이를 수 있는 것으로 예측되었다. 따라서 보리밥나무는 이동시기의 조류에게 중요한 먹이자원을 제공하고, 조류는 보리밥나무 종자의 산포자로서 새로운 지역으로 정착할 수 있는 기회를 주는 것으로 판단된다. 이와 같은 개척자 식물과 종자 산포자간의 상호작용은 척박한 해안 및 도서지역의 훼손된 상록활엽수림과 난대림 생태계의 자연 복원에 활용될 수 있을 것으로 기대된다.

• 한국환경과학회지
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• 제25권5호
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• pp.635-644
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• 2016

Birds play a main role in the formation and change of forest structures as they are seed-dispersal agents. This study aims to identify birds consuming fruits and seeds of the tree and their associated fruits and seeds on Jeju Island in the context on the forest restoration in Korea. We conducted field surveys twice a month from 2013 to 2015 at nine study sites located across Jeju Island and collected available photographic and observation records. A total of 50 species of birds consuming fruits and seeds of the tree were identified and birds belonging to Bombycillidae, Pycnonotidae, Zosteropidae, Sturnidae and Fringillidae were confirmed as major birds consuming fruits and seeds of the tree. Gulping was the dominant type of feeding as well as crushing, but relationship between the size of a bird and the number of fruit and seed species used by the bird was not significant. We also documented that 118 fruit and seed species were consumed by birds and that shrubby fruits and seeds were more consumed by birds than those of other plant types. The relative consumption rate of fruits and seeds ranged from 0.02 to 0.44, but five species were the most important fruits and seeds for birds. Our finding suggest that avian frugivorous gulpers will benefit the seed dispersal, especially of five fruiting plants, providing useful baseline data for forest restoration and urban park design.