Insect Community Response Following Wildfire in an Eastern North American Pine Barrens

Abstract

Ecosystem recovery following wildfire is heavily dependent upon fire severity and frequency, as well as factors such as regional topography and connectivity to unburned patches. Insects are an often-overlooked group of organisms impacted by fire and play crucial roles in many ecosystem services. Flying insects are particularly capable of avoiding fire, returning to burned patches following the initial disturbance, making them an important group to study when assessing wildfire impacts. Following a wildfire in July of 2018 at the Altona Flat Rock jack pine barrens in northeastern New York, insects were collected from an unburned reference site and a post-fire site using malaise traps. Samples were collected in the 2018, 2019, and 2020 field seasons. Insect groups were found to have three main responses to the disturbance event: increased abundance post-fire, unchanged abundance post-fire, or reduced abundance post-fire. Several dipteran families and some non-dipteran groups were present in greater abundance in the post-fire study site, such as Diptera Polleniidae, which increased in abundance immediately following the disturbance in 2018. Other fire-adapted taxa exhibited a more delayed positive response in 2019 and 2020. Diversity, particularly among Diptera, increased with time since the disturbance at the post-fire site. Many taxa declined in response to fire disturbance, including Lepidoptera and several Diptera families, most likely due to habitat, moisture, and organic matter requirements. Future studies could prove beneficial in understanding the recovery of this community and informing land management practices.

Keywords

• insect community structure
• habitat resilience
• wildfire
• pine barrens