Summer Resource Selection and Identification of Important Habitat Prior to Industrial Development for the Teshekpuk Caribou Herd in Northern Alaska

Abstract

Many caribou (Rangifer tarandus) populations are declining worldwide in part due to disturbance from human development. Prior to human development, important areas of habitat should be identified to help managers minimize adverse effects. Resource selection functions can help identify these areas by providing a link between space use and landscape attributes. We estimated resource selection during five summer periods at two spatial scales for the Teshekpuk Caribou Herd in northern Alaska prior to industrial development to identify areas of high predicted use for the herd. Additionally, given the strong influence parturition and insect harassment have on space use, we determined how selection differed between parturient and non-parturient females, and between periods with and without insect harassment. We used location data acquired between 2004–2010 for 41 female caribou to estimate resource selection functions. Patterns of selection varied through summer but caribou consistently avoided patches of flooded vegetation and selected areas with a high density of sedge-grass meadow. Predicted use by parturient females during calving was almost entirely restricted to the area surrounding Teshekpuk Lake presumably due to high concentration of sedge-grass meadows, whereas selection for this area by non-parturient females was less strong. When insect harassment was low, caribou primarily selected the areas around Teshekpuk Lake but when it was high, caribou used areas having climates where insect abundance would be lower (i.e., coastal margins, gravel bars). Areas with a high probability of use were predominately restricted to the area surrounding Teshekpuk Lake except during late summer when high use areas were less aggregated because of more general patterns of resource selection. Planning is currently underway for establishing where oil and gas development can occur in the herd’s range, so our results provide land managers with information that can help predict and minimize impacts of development on the herd.

NDVI exhibits mixed success in predicting spatiotemporal variation in caribou summer forage quality and quantity

“…As the summer progresses, however, caribou forage biomass continues to increase as forage quality declines (Fig. For example, NDVI in June has been useful for predicting early summer caribou habitat use and nutritional condition (Griffith , Couturier et al 2009), while NDVI metrics taken across the growing season have generally been weak predictors of caribou behavior (Parrett 2007, Wilson et al 2012) and even yielded negative relationships with caribou abundance (Fauchald et al 2017). This pattern was reflected in our results, as DE and biomass had much stronger associations with NDVI across the summer than N or DN.…”

“…For example, June NDVI was both positively (Griffith et al 2002) and negatively (Parrett 2007) correlated with caribou habitat use on Arctic calving grounds, while NDVI measures of plant phenology had relatively little influence on caribou summer resource selection (Parrett 2007, Wilson et al 2012. For example, June NDVI was both positively (Griffith et al 2002) and negatively (Parrett 2007) correlated with caribou habitat use on Arctic calving grounds, while NDVI measures of plant phenology had relatively little influence on caribou summer resource selection (Parrett 2007, Wilson et al 2012.…”

Winter Resource Selection by Mule Deer on the Wyoming–Colorado Border Prior to Wind Energy Development

“…Last, and most importantly, these results can be used as baseline data for which future studies of this population of mule deer can be assessed in response to development and long-term persistence of infrastructure. When development occurs, wildlife may lose habitat directly when native vegetation is converted to sites for infrastructure, or indirectly through avoidance behaviors (Sawyer et al 2006Wilson et al 2012). At this time, if development occurs in preferred areas, it is unknown how deer will respond to direct loss of habitat and indirect changes in behavior (Wilson et al 2012), and whether this will have any long-term implications on population demographics (Dzialak et al 2011b).…”

Caribou Use of Habitat Near Energy Development in Arctic Alaska

“…S1, available online in Supporting Information), well within the distance they would be expected to exhibit any responses to development based on past research (Dau and Cameron ; Cameron et al , ). Additionally, this time frame encapsulated 3 different periods recognized by management agencies where caribou exhibit distinct behavioral patterns: calving (1–15 Jun), post‐calving (16–24 Jun), and mosquito harassment (25 Jun–15 Jul; Person et al , Wilson et al ). All collared individuals in our analysis appeared to be exposed to energy infrastructure during early summer; the 100% minimum convex polygons (MCP) for each collared female each year (1 Jun–15 Jul) overlapped infrastructure.…”