History of Fire

Over the past decade, Hawai'i has experienced an average of >1,000 ignitions burning >20,000 acres (8,000 ha) each year across the main inhabited islands.  Fire response agencies are able to contain 90% of wildfire ignitions to less than one acre in size, but large fires (>1000 acres) have occurred on all islands, and happen multiple times each year across the state.

Hawai‘i Fire History and Agricultural Decline (Credit: Trauernicht & HWMO)
Hawaii 1999 - 2023 fires

Large Fire Perimeter Data for Hawai'i

This data set contains polygons of wildland fire perimeters for the main Hawaiian Islands from 1999 to 2022. It compiles prior mapping efforts by different organizations with fires mapped from 2012 onwards by Dr. Clay Trauernicht ([email protected]) in the Department of Natural Resources and Environmental Management (NREM) at the University of Hawai'i at Mānoa.  The data tracks and maps all fires greater than or equal to 20 hectares (50 acres), but some smaller fires are be included.

NOTE ON DATA USE AND DISTRIBUTION: We actively encourage use of this data set for scientific purposes and planning by communities, natural resource managers, and emergency response agencies. Users are prohibited from any commercial, non-free resale, or redistribution without explicit written permission from Clay Trauernicht. Download Fire Perimeters HERE

Wildfire Threats and Impacts

Nearly all fires in Hawai'i are human-caused and they often pose threats to communities and natural and cultural resources.  Having evolved in the absence of frequent fires, Hawai'i's native ecosystems are particularly vulnerable to fire disturbance, which is often associated with the spread and establishment of nonnative grass and shrub species.

Wildfire Drivers

The primary drivers of fire occurrence are: frequent, mostly human-caused ignitions; expansion of nonnative, fire-prone grasslands and shrublands over c. 25% of state land area; and strong rain shadow effects and episodic drought create which create year-round fire weather.

Statewide Wildfire Ignitions (2016)
Palehua, O`ahu, Aug 2014 (Credit: Clay Trauernicht)

Recent Resources For Hawai‘i

Webinar: Changing Climate and Wildfire in Hawaiʻi

April 18, 2023

In this joint webinar hosted by the Pacific Fire Exchange and the Pacific Regional Invasive Species Climate Change, we tackle the climate crisis in Hawai`i and how this affects the risk of wildfire as well as the impacts to people and the archipelago’s unique resources.

Talk Story Tuesdays: Informing Contemporary Wildfire Science from Historical Hawaiian Language Newspapers

March 21, 2023

In this Pacific Fire Exchange talk story Q&A session, we speak with Dr. Clay Trauernicht and Dr. Alyssa Anderson, University of Hawai`i at Mānoa about wildfire in Hawai`i in the context of Hawaiian language newspapers as well as the historical landscape changes of the 20th century.

Talk Story Tuesdays: Grazing to Reduce Blazing Part II

February 21, 2023

In this Pacific Fire Exchange talk story Q&A session, we round up the latest research, past and present for managers and landowners wanting to understand more about how our four-legged friends (goats, sheep, cows, etc.) if managed properly can help reduce blazing and wildland fire. This month’s science share out and conversation was with Dr. Clay Trauernicht, University of Hawai`i at Mānoa Ecosystems and Fire Specialist; Raia Olsen of O‘ahu Grazers and Dr. Elliott Parsons, formerly with the Department of Land and Natural Resources. They presented the how-tos on hiring island professional grazers and lessons learned for contract grazing.