Today at the ILMF event in Denver, Wesley Newton from the U.S. Geological Survey discussed the use of lidar for wildlife habitat modeling. The USGS works to assess the quality of habitat, population demographics, species survival, and why wildlife are found in specific habitats. The group works to model and explain the mix of wildlife in specific habitat types for management actions.
Different species require different vertical structure in grasslands and within forests. The presentation discussed different bird species with different forest structure types. Bird species diversity is often dependent on the amount of foliage, with more birds in areas that are denser.
A management dilemma that the USGS faces is the competing needs of different species. With different, the challenge is to simultaneously manage habitat across species. The USGS relies heavily on statistical models, with the use of study plots that are quantified for vegetation types and structure, that can then be extrapolated to larger forests. Other landscape metrics and land cover methods with imagery and other sources to understand the variation.
The measurement of wildlife include the presence of species, the count the survival rate, and the biomass. The general species model include stand level metrics, landscape metrics with imagery, features with GIS layers, and then the fieldwork. The goal is to develop a number of plausible models, that are continually updated, and then compared.
Lidar has been helping a great deal at the forest level, with data that can’t be quantified in other ways. The lidar point cloud is subtracted from the digital elevation model for a canopy height model, with removal of buildings and other vertical structures. The details on variability are then put into different height bins for canopy, with vertical profiles for different forests. There are fifty different explanatory variables for forests that are then used to predict the species abundance. Models are applied to the landscape, with adaptive models that monitor and model water flows and other variables, to understand the impact of change.
The USGS has flown lidar in Maine for woodcock habitat. In Nebraska the USGS is using lidar to quantify the habitat along the South Platte River, which is ideal habitat for Sandhill Cranes. Not only is the lidar used for habitat assessment, but it’s also being considered as a means to count the cranes. In Wyoming the USGS is using lidar for sagebrush habitat, where different species require different heights of brush. In Nevada, the USGS are mapping streams for spawning habitat of cutthroat trout, understanding good shading areas. The changes within all of these habitats are being closely monitored to understand ongoing impacts.