NWT RESEARCH DATABASE

Tags: physical sciences, vegetation, caribou, fire ecology, forest regrowth

Objective(s): To collect data for predictive caribou habitat mapping within the forested areas of the Taiga Plains and Taiga Shield Ecoregions in NT.

Project Description: The main objective of this fieldwork is to support the collection of data for predictive caribou habitat mapping within the forested areas of the Taiga Plains and Taiga Shield Ecoregions in NWT, roughly south of Great Bear Lake. The research team will complete the establishment of a network of long-term study plots across a range of fire characteristics and vegetation types, where the team will measure the rate and direction of forest and caribou forage recovery following fire. The sample design will enable the team to model how these rates and directions vary with initial conditions, fire severity and other factors. The survey design and field protocols will facilitate future re-measurements. Site selection: As this is an extension of previous work, the research team will provide the full sample design with indication of parts of the sampling that are already completed. Based on the chronosequences sampling in the Taiga Plains, the team expect to establish 3-5 plots within each combination of time-since-fire class and vegetation type. This sampling rate many increase slightly if the number of vegetation types is lower than on the Taiga Plains. The team will also revisit previously sampled burn sites. Combined, these chronosequences and repeated measurements will allow the team to estimate rates of recovery of different habitat types as a function of time since fire. Plots will be geo-referenced at high precision and marked in the field. The research team will select sites based on: 1) Fire age using fire history maps (c1960-2014): new (2014), medium (30-50 years; tightly bracketing the time period at which the boreal caribou management strategy considers burned sites to have become useable), and old (> 60 years). Forest Inventory data is not available on the Taiga Shield; the team will use older aerial photography to identify accessible sites in older, where possible. 2) Vegetation or landcover class. Sampling will include all dominant forest types and land cover types used commonly by caribou, as determined from collar locations for the Shield, if available. 3) Proximity to communities, roads, and water to facilitate access. Ground sampling: In 2015, the team sampled the 2014 burns to capture immediate post-fire conditions. In 2016 and 2017 the team resampled 2014 burns including the establishment of seed addition experiments to evaluate the role of seed limitation in determining regeneration outcomes and sampled older burns on the Taiga Plains. The research team will undertake the following ground sampling: 1) Sample older stands (30-50 years and 60+ years) on the Taiga Shield to facilitate a full chronosequence. This sampling will occur in stands of different ages accessible by water from the communities of Gameti and Wekweeti and by road along the Ingraham Trail. 2) Resample permanent plots following fires near Tibbitt and Gordon Lakes in 1996 and 1998 and for which the research team have 10-years of continuous data on many aspects of post-fire recovery. Resampling during 2018 will provide the 20-year time post-fire time point and produce a truly unique post-fire time series. At all plots, the team will measure the following attributes: a) vegetation composition and abundance, soil characteristics, and depth to frost table; b) direction and rate of forest recovery: the team will establish forest inventory plots to relate ground data to remotely sensed products; and, c) caribou forage including the relative abundance and biomass of plants and lichens (arboreal and ground-dwelling) used by caribou and other ungulates such as moose. Through the previous work the research team have developed excellent relationships between lichen biomass and volume that support characterization of lichen biomass accumulation through time. The team have made great effort to engage communities in this research program including participation in community meetings, open house events to discuss the research casually, on-the-land events with youth and elders, community outreach initiatives in Territorial parks, and involvement of community members in the research. In this final year of the project the team will also work to develop plain language materials to help support communication of the results. The fieldwork for this study will be conducted from June 1, 2018 to October 31, 2018.