Testing the potential of lightweight drones as a tool for monitoring the status of colonially breeding Saunders's gulls (Saundersilarus saundersi)

국문 초록 (Abstract)

무인항공기는 최근 물새류의 번식지를 포함한 다양한 야생 동물 현황을 조사하는데 사용되고 있으며, 비침습적인 방식으로 야생동물의 개체수와 분포에 대한 조사 데이터를 얻는데 용이하다. 검은머리갈매기(Saundersilarus saundersi)는 갯벌 주변 매립지에서 집단 번식하는 물새류로, 집단 방어행동으로 인해 둥지를 직접 조사 등 인위적인 방해 없이 번식현황을 파악하기 어려운 것으로 알려져 있다. 본 연구에서는 인천 매립지 서식 검은머리갈매기 집단 번식지에서 소형 드론을 사용하여 번식 현황을 조사하였다. 2018년, 선조사 방식의 Distance Sampling 방법으로 번식기 동안 반복 조사를 실시했다. 드론으로 녹화된 비디오 데이터는 조사 선에서 개체 또는 둥지까지의 거리로 변환하여 기록하였다. 결과적으로, 번식기 동안 집단 번식지의 밀도가 급격히 감소하였으며, 2018년 집단 번식은 둥지포식에 의해 완전한 실패하는 패턴을 보였다. 따라서, Distance Sampling 기반으로 비침습적이고 저비용의 무인항공기 조사방법은 데이터 수집과 추정에 불확실성이 존재하지만, 물새류 집단 번식지 모니터링에 유용하다고 추론된다.

다국어 초록 (Multilingual Abstract)

Unmanned aerial vehicles (UAV) are recently used to survey a diversity of wildlife status, including breeding colonies of seabirds, which provides empirical data of wildlife numbers and distributions with fewer disturbances. The Saunders’s gull (Saundersilarus saundersi) is a colonially breeding seabird species on reclaimed lands near mudflats. It is also known to be difficult to estimate the breeding status without disturbance such as directly checking nests due to their group defense behavior. In this study, we used a lightweight drone to survey the breeding status of Saunders’s gulls in a reclaimed area of Incheon, Republic of Korea. Then, we approached a distance sampling method with fixed line transects along multiple surveys during the breeding season of 2018. The video data recorded by UAV were transcribed into individual- or nest-based distances from each line transect. The results of our survey indicated that the relative size of breeding colony rapidly decreased throughout the breeding season, showing the complete failure pattern of the breeding colony in 2018. We suggest that this non-invasive, less expensive UAV method with distance sampling may be useful to estimate the breeding status of seabird colonies in spite of uncertainty of data collection and estimation.

목차 (Table of Contents)

• Abstract
• 요약
• Introduction
• Materials and Methods
• Results
• Discussion
• References

참고문헌 (Reference)

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