Assessing the activity of deer and their influence on vegetation in a wetland using automatic cameras and low altitude remote sensing (LARS)

A Review of Unoccupied Aerial Vehicle Use in Wetland Applications: Emerging Opportunities in Approach, Technology, and Data

“…One study assessed a broader suite of coastal habitats with salt marshes and mudflats among those [104]. Among less directly habitat-focused studies, one paper from the wetland health category focused on a rare wetland plant species indicator of susceptible deer activity in a wetland with increasing deer population [108], while another application discussed an abiotic transformation of the landscape induced by American beaver (Castor canadensis) [127]. Most frequently, such analyses targeted: 1) animal populations or colonies [36,63,101,103]; 2) habitat components [99][100][101]; and 3) evidence of wildlife activity on the landscape [96,100,108,127].…”

“…UAV-induced disturbance becomes less concerning in studies focusing on detecting habitat elements [99,104] or impacts of wildlife activity on wetland landscapes [96,108], where flights can be conducted outside of the primary breeding and nesting seasons. Specific uses of UAV data in such habitat-oriented assessments are versatile, including both visual assessments of recognizable features, such as beaver dams [100] and classifications of UAV imagery into habitat features of specific relevance to species, such as tussocks in [99], or mudflats, oyster reefs, and salt marshes in [104].…”

“…Specific uses of UAV data in such habitat-oriented assessments are versatile, including both visual assessments of recognizable features, such as beaver dams [100] and classifications of UAV imagery into habitat features of specific relevance to species, such as tussocks in [99], or mudflats, oyster reefs, and salt marshes in [104]. Notably, modifications of the landscape by wildlife can be seen both as an indicators of conservation success, e.g., when signifying the outcome of reintroduction [100], and as a disturbance and ecosystem change drivers, e.g., in cases of grazing and trampling [96,108]. Given the indirect nature of such evidence, UAV surveys should ideally be accompanied or validated with other assessments, such as in situ camera traps, to provide local nuances on animal movement and habitat use for more robust and comprehensive conclusions about wildlife population status and activity [108].…”

“…Notably, modifications of the landscape by wildlife can be seen both as an indicators of conservation success, e.g., when signifying the outcome of reintroduction [100], and as a disturbance and ecosystem change drivers, e.g., in cases of grazing and trampling [96,108]. Given the indirect nature of such evidence, UAV surveys should ideally be accompanied or validated with other assessments, such as in situ camera traps, to provide local nuances on animal movement and habitat use for more robust and comprehensive conclusions about wildlife population status and activity [108].…”

“…Emerging applications of UAVs are extremely promising for informing cost-effective yet spatially comprehensive indicators of wetland health at the landscape scale and support long-term monitoring needs. Our pool of studies in this category included seven mapping, three modeling, three change analysis, and one novel method application that either targeted a particular aspect of wetland ecological health such as water quality (e.g., [105]) and vegetation indicators (e.g., [42,108,111]) or assessed the overall ecological status using different indicators (e.g., [7,34]). These studies employed RGB, Multispectral, Hyperspectral, and SAR sensors, as well as combinations of RGB and Multispectral and RGB and Thermal sensors (Figure 3).…”