iForest - Biogeosciences and Forestry


Modeling the risk of illegal forest activity and its distribution in the southeastern region of the Sierra Madre Mountain Range, Philippines

Jhun B Barit (1-2), Kwanghun Choi (2), Dongwook W Ko (2)   

iForest - Biogeosciences and Forestry, Volume 15, Issue 1, Pages 63-70 (2022)
doi: https://doi.org/10.3832/ifor3937-014
Published: Feb 21, 2022 - Copyright © 2022 SISEF

Research Articles

Illegal activity within protected forests, such as illegal logging, slash-and-burn farming, and agricultural expansion, has brought many plant and animal species to the brink of extinction and threatens various conservation efforts. The Philippine government has introduced a number of actions to combat environmental degradation, including the use of mobile platforms such as the SMART-Lawin system to collect patrol data from the field, which represents a remarkable step towards data-driven conservation management. However, it remains difficult to control illegal forest activity within protected landscapes due to limited patrol and law enforcement resources. A better understanding of the spatial distribution of illegal activity is crucial to strengthening and efficiently implementing forest protection practices. In the present study, we predicted the spatial distribution of illegal activity and identified the associated environmental factors using maximum entropy modeling (MaxEnt). Patrol data collected using the SMART-Lawin system from the Baliuag Conservation Area for the period 2017-2019 were used to train and validate the MaxEnt models. We tuned the MaxEnt parameter setting using the ENMeval package in R to overcome sampling bias, avoid overfitting, and balance model complexity. The resulting MaxEnt models provided a clear understanding of the overall risk of illegal activity and its spatial distribution within the conservation area. This study demonstrated the potential utility of data-driven models developed from patrol observation records. The output of this research is beneficial for conservation managers who are required to allocate limited resources and make informed management decisions.


Philippines, SMART, Ranger Patrol Data, Illegal Forest Activity, Protected Area Management

Authors’ address

Jhun B Barit
Department of Environment and Natural Resources - DENR (Philippines)
Jhun B Barit
Kwanghun Choi 0000-0003-0030-8876
Dongwook W Ko
Department of Forest Environment and Systems, Kookmin University (South Korea)

Corresponding author

Dongwook W Ko


Barit JB, Choi K, Ko DW (2022). Modeling the risk of illegal forest activity and its distribution in the southeastern region of the Sierra Madre Mountain Range, Philippines. iForest 15: 63-70. - doi: 10.3832/ifor3937-014

Academic Editor

Maurizio Marchi

Paper history

Received: Jul 28, 2021
Accepted: Dec 16, 2021

First online: Feb 21, 2022
Publication Date: Feb 28, 2022
Publication Time: 2.23 months

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