Spatial and Temporal Patterns of Fire on Saipan, CNMI

How people, rainfall and vegetation shape tropical island fire regimes across Micronesia

“…Our use of simplified land cover (i.e. savanna vs. forest) drew on established interdependencies between savannas and fire demonstrated globally (Murphy & Bowman, 2012; Staver et al., 2011) as well as prior island studies (Bubb & Williams, 2022; Dendy, Mesubed, Colin, et al., 2022; Goel et al., 2020; Ibanez et al., 2013; Phelps et al., 2022; Trauernicht, Pickett, et al., 2015). Briefly, the positive feedback between fire and open, grassy, shrub‐ or fern‐dominated vegetation allows savannas to establish and persist in regions climatically suited for tropical forest, creating heterogenous landscape mosaics at multiple spatial scales.…”

“…The extent of fire in the region and its clear relationship with people indicate that local knowledge of burning has potential lessons for contemporary land care in Micronesia (Bubb & Williams, 2022; Dendy, Mesubed, Colin, et al., 2022; Minton, 2006; Povak et al., 2020). For example, “farm fires” were the most common cause cited by Palauans as ignition sources on Babeldaob, while “hunting and gathering fires” accounted for most of the area burned, followed by “arson fires” (Dendy, Mesubed, Colin, et al., 2022).…”

“…Studies also highlight the need for novel risk assessment methods given unique vegetation and highly variable climates on islands (Trauernicht, 2019; Van Beusekom et al., 2018). Fewer studies engage social dimensions or patterns in the frequency, intensity and extent of burning at island or regional scales (Bubb & Williams, 2022; Dendy, Mesubed, Colin, et al., 2022; Ibanez et al., 2013; Phelps et al., 2022; Trauernicht, Pickett, et al., 2015).…”

“…Our objectives were to: (1) Describe the relationships among contemporary fire activity, vegetation, rainfall, and island geography and population across the region; (2) examine the spatial associations of forest and savanna vegetation with fire and soil types; and (3) use regional rainfall variability to examine the extent to which fire and savanna distribution are climate‐limited in terms of both annual and seasonal rainfall variability. Our approach is largely descriptive, yet quantifying the frequency and extent of fire and examining the influence of multiple factors on fire and vegetation is a critical need for the region (Bubb & Williams, 2022; Dendy, Mesubed, Colin, et al., 2022; Trauernicht, Pickett, et al., 2018). This work directly contributes to community and agency efforts to better integrate fire risk and planning into ecosystem and community protection in Pacific island landscapes.…”

Dynamics of Anthropogenic Wildfire on Babeldaob Island (Palau) as Revealed by Fire History

“…More recently, remote sensing techniques incorporating satellite or aerial imagery have been widely applied to estimate burned area and other wildfire metrics, with high-to-moderate-resolution imagery being most appropriately used at local scales [19]. Various burned area products and spectral indices have been developed and used to map burned areas independently of active fire products, and the Normalized Burn Ratio (NBR) has demonstrated utility in grassland habitats including on small tropical islands [19,20]. Unfortunately, although these current methods are suitable for most research purposes, they are prone to high rates of commission and omission errors; thus, research into methods that increase burned area accuracy is still needed [20,21].…”