Woodland caribou is a species at risk because of northward expansion of resource development activity. Some herds are in dire condition and well below self-sustainability, while others are only moderately below self-sustaining levels. Given limited conservation dollars, what are the most effective conservation actions, and how much money needs to be spent? Which herds should be a priority for conservation efforts? The purpose of this model to provide insight into these difficult conservation questions.
This model was developed by Rob Rempel and Jen Shuter at the Centre for Northern Forest Ecosystem Research, and was based in part on input from attendees of a modelling workshop ("Modelling the Caribou Questions") held at the 16th North American Caribou Workshop in Thunder Bay, Ontario, May 2016.
This model simulates critical components of the predator-prey systems for caribou, and keeps tracks of rates and costs for conservation actions that are currently being used in different jurisdictions in North America. The purpose of the model is to provide insight into critical conservation questions.
There are 7 principal model components or sub-models that lead into the Caribou Dynamics Model. We will expand and briefly discuss a few of these sub-models in the next few slides.
The wolf sub-model simulates the number of wolves in the population. Wolf birth rate is affected by available prey (deer and moose), while death rate is affected by trapping and hunting. Conservation actions can decrease wolf populations indirectly by degrading prey habitat or increasing hunting pressure on prey, but also directly by paying hunters to kill or trap wolves. The costs to kill or trap a wolf are estimated and tracked.
In the deer simulation model, population recruitment is affected principally by winter severity. Both wolf predation and hunting will decrease deer populations directly, while additional deaths occur from density independent factors (e.g., old age). Hunting regulations can be changed to increase harvest levels.
In the moose simulation model recruitment is affected by habitat suitability and winter severity, while death rate is affected by wolf predation, hunting and density independent death (e.g., old age, parasites, accidents). Hunting regulations can be changed to increase harvest levels.
The linear features sub-submodel simulates the accumulation and removal of roads. The effect of roads on wolf predatation rates, the rate of new road construction and decommissioning, and the cost of decommissioning are model components that allow us to explore the cost-effectiveness of roads management for caribou conservation.
The caribou dynamics model brings all the model components together. Output from sub-models (e.g., number of wolves), are imported (by ghosting) into the caribou dynamics model. All models run simultaneously so feedbacks and interactions operate as expected. Key conservation parameters (e.g., road construction and decommissioning rates and costs) can be adjusted in the control panel. The gaming objective is to maintain a viable population of caribou for the lowest cost possible, and to gain insights as to how, when and where limited conservation dollars should be directed.
The Total Cost sub-model is the main accounting model that keeps track of costs used to sustain a caribou herd or population. These values are imported from appropriate sub-models, and their contribution to total cost will depend upon options and parameters selected by the model user.