Reindeer Husbandry: A Practical Decision-Tool for Adaption of Herds to Rangelands

In this report focus is on the adaptation of reindeer herds to available food resources in a district, i.e. to the availability and quality of winter and summer ranges. Previous laboratory experiments and field experiences suggest that practical management is complicated by the dynamics involved and by a lack of precise information. Furthermore, formal analyses to find optimal herd sizes, to find optimal learning strategies, are both complicated to carry out and difficult to explain to decision-makers. Hence one is faced with a pedagogical problem. The purpose of the report is to provide a decision-tool which can capture the essence of earlier normative studies, and be sufficiently simple that it can be used in practice. In short, the decision-tool helps organise time-series information such that it becomes directly useful for decision-making. The derivation of the decision-tool with its equations is not easy to popularise. However, to foster active and correct use, a training simulator goes along with the decision-tool. Hopefully, the simulator and a separate user’s guide will help build the intuition needed, without the explicit knowledge of underlying mathematics. In earlier studies it has been found that decision-maker involvement in model building is important for the implementation of policy recommendations, so-called “group model-building”. Using the tool, decision-makers are not directly involved in the modelling, however they do provide data and they draw their own policy conclusions. In this connection an important function of the decision-tool is to transform the raw data to a form that help decision-makers improve their mental models and choose appropriate heuristics. In the report, the tool is used to study several cases from the Nordic countries. Concerning winter lichen ranges, it is found that the tool can provide considerable guidance based on prior data even when fielt data are scarce and speculative. In cases where good data are available, acceptable fits are found between the proposed model for lichen growth and the data. The case of Snøhetta indicates that heavy grazing by reindeer can lead to a more or less permanent reduction in the lichen growth potential. For both winter and summer ranges estimates of near-optimal herd sizes are obtained that are consistent with results from more expensive types of studies. Most of the investigated ranges show tendencies towards excessively large herd sizes and overgrazing. This is the same tendency towards overutilisation that is seen for many renewable resources, even those that are regulated by public agencies. Hence, there seems to be a need for the type of tool that has been developed. The project has been financed by “Nordisk ministerråd” under the program “Nordiska miljöstrategin för jord- och skogsbruk 1996-1999”. It was initiated and administered by “Nordisk organ for reinforskning”, NOR.