Likelihood of occurrence of bark beetle attacks on conifer forests in Honduras under normal and climate change scenarios

Abstract

Conifer forests cover approximately 27% of Honduras (∼3 million ha), and have been traditionally affected by bark beetle (Dendroctonus frontalis) outbreaks. These outbreaks impact ecosystem health and predispose more attacks. We developed a logistic model to assess the forests’ susceptibility to a beetle attack. Models were fitted using climatic, topographic and remote sensing variables. We show a method to generate pseudo-absences based on a multi-temporal wetness index. Our optimized threshold to convert the continuum of probabilities into 0 and 1 value was 0.65. Our overall accuracy was 68.7%. We also developed models that integrate climate change scenarios. Our predictions signal an increase in the overall susceptibility for an attack when including climate change scenarios. To the best of our knowledge this is the first effort to develop a spatially explicit model of the probability of beetle outbreaks in a Central American country.

Keywords:

• Honduras
• logistic regression
• bark beetle outbreaks
• climate change
• remote sensing

Acknowledgements

We would like to acknowledge the Sistema de Informacion Forestal (SIFOR) at AFE-COHDEFOR in Tegucigalpa, Honduras for sharing field datasets and for sharing professional advice about the quality of data. We also want to recognize the logistic support received from the Tropical Forest and Climate Change Adaptation TROFCCA project. Without the help of SIFOR and TROFCCA we would have never been able to conduct our research. We also want to thank two anonymous reviewers whose observations and comments greatly contributed to this article.