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2025 Vol.12, Issue 3

Original Article

Minimum Population Estimation Algorithm for Wildlife Using Camera Trap Data : Habitat-Based Cost-Path and Graph Structure Analysis

카메라 트랩 데이터를 활용한 야생동물 최소 개체군 추정 알고리즘 : 서식지 기반 비용경로와 그래프 구조분석을 중심으로

Minkyu Park1*
박 민규1*
1CTO, R&D Division, SeeNature Corp., Daegu 42614, Korea
1주식회사 씨네이처 연구개발본부 CTO
*Corresponding Author
30 September 2025. pp. 127-140
PDF XML Citation
Abstract

A novel algorithm for estimating the minimum population size (MPS) of wildlife using camera trap data was developed and empirically applied to the long-tailed goral (Naemorhedus caudatus) in Seoraksan National Park. The proposed algorithm spatiotemporally classifies detection events that cannot represent the same individual based on the physical movement potential between camera trap detection events and determines the dependency of events. To validate the effectiveness of the algorithm, we applied it to 1,185 goral detection events collected over 420 days in the Osaek area of Seoraksan. The results estimated the minimum number of gorals at 28 individuals, which showed no statistically significant difference from the estimate based on fecal DNA analysis in the same area (25 individuals, 95% confidence interval 21–29). This study demonstrates that reliable minimum population estimation is feasible even when individual identification within the same species is impossible, indicating potential applications in various wildlife conservation and population management studies.

Keywords
Connected components
Conservative estimation
Event etection
Movement resistance surface
Spatiotemporal independence

본 연구는 카메라 트랩 데이터를 활용하여 야생동물의 최소 개체군 크기(MPS)를 추정할 수 있는 새로운 알고리즘을 제안하고, 설악산국립공원에서 산양(Naemorhedus caudatus)을 대상으로 실증 적용하였다. 제안된 알고리즘은 카메라 트랩 탐지 이벤트 간의 물리적 이동 가능성에 근거하여 동일 개체가 될 수 없는 이벤트들을 시공간적으로 분류하고 이벤트의 종속 여부를 판단한다. 본 알고리즘의 실효성을 검증하기 위해 설악산 오색 지역에서 420일간 수집한 1,185건의 산양 탐지 이벤트를 알고리즘에 적용하였고, 그 결과 산양의 최소 개체수는 28개체로 추정되었으며, 이는 동일 지역의 산양 분변 DNA 분석 기반 추정치(25개체, 95% 신뢰구간 21–29)와 통계적으로 유의한 차이를 보이지 않았다. 이 연구는 동일 종의 개체별 식별이 불가능한 상황에서도 신뢰성 있는 최소 개체군 추정이 가능함을 입증하며, 향후 다양한 야생동물 보전 및 개체군 관리 연구에 활용될 가능성을 보였다.

키워드
연결성분
보수적 추정
탐지 이벤트
이동 저항 표면
시공간 독립성
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Information
  • Publisher :Korean Society of Ecology and Infrastructure Engineering
  • Publisher(Ko) :응용생태공학회
  • Journal Title :Ecology and Resilient Infrastructure
  • Journal Title(Ko) :응용생태공학회 논문집
  • Volume : 12
  • No :3
  • Pages :127-140
  • Received Date : 2025-07-24
  • Revised Date : 2025-08-14
  • Accepted Date : 2025-08-25
  • DOI :https://doi.org/10.17820/eri.2025.12.3.127
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