Shrub thickets are most threatened by development , sea level rise , king tides , extreme weather events , grey infrastructure , and invasive species , such as Chinese tallow trees ( Gramling , 2012 ; Kiawah Conservancy , forthcoming 2023 ). In addition , shrub thickets serve as a barrier to protect vegetation in the interior maritime forests from exposure to salt spray and to decrease wave action from tidal surge . Shrubby vegetation and trees with stunted growth are characteristic of these habitats , brought about by the exposure to extreme environmental conditions ( e . g ., aerosol salts , inundation , high soil salinity ). Analyzing their vegetative productivity over time can provide information about the impact of stressors on these habitats .
Vegetative productivity trends were analyzed using aerial imagery from 2017 and 2021 . Ideally , neutral or increasing trends are desirable in these areas as they indicate stable habitats or more vegetative growth , respectively . A majority of the areas with shrub thickets show ideal conditions , with some variation in productivity across the island . The best conditions were noted around the upstream areas of Bass and Cinder Creeks on the eastern portion of the island . The data suggest there were declines in shrub thicket productivity in the region near Little Bear Island . The reduction in vegetative cover which provides stop-over habitat for fall migrating birds was also noted by Town Wildlife Biologists during recent banding seasons .
One particular concern is the prevalence of tidal inundation and the resulting impacts on shrub thicket vegetation . Analyzing tide levels and surface elevations across the watershed provides a glimpse into potential areas impacted by inundation for long-term vegetation monitoring . According to data from the Charleston Harbor Tide Gauge for 2022 , Charleston County experienced 114 days of king tide flooding . Compared to tidal data from recent years , the frequency of these events are higher than normal . There is high confidence among the majority of scientists that the frequency of tidal flooding will increase in the long-term due to rising sea levels ( IPCC , 2021 ). Sustained flooding from tidal inundation events places environmental stress on woody growth in these areas and leads to declines in vegetative productivity . This is shown through a decrease in average values from the vegetation index datasets over time .
Shrub Thickets