Spacing as Affected by Territorial Behavior, Habitat and Nutrition in Red Grouse (Lagopus I. Scoticus)

Abstract

This essay reviews studies of how red grouse (Lagopus lagopus scoticus) behave so that they space themselves out, and considers how this social behavior is related to the regulation of populations. Ecologists are becoming increasingly aware that changes in social behavior and population numbers are often associated, and that food shortage, predation, disease and bad weather are often not sufficient to give a full explanation of changes in numbers. Some workers consider that changes in food supply are needed to cause fluctuations in numbers, but others that they are not necessary. One of the difficulties is that food quality in biochemical or nutrient terms, as distinct from mere quantity of material, has been greatly neglected in ecology, despite its well-established importance for the survival, weight, physiology, reproduction and behavior of domestic animals and man. Furthermore, the different views of Andrewartha & Birch (1), Wynne-Edwards (20), Lack (6) and Chitty (3), show that theoretical views on the mechanics of population control are widely different. Anyone surveying the literature will rapidly conclude that remarkably few studies have been done on the inter-relationships between behavior, population, and food or other features in the environment. There are plenty of studies on any one of these aspects, and quite a number on population-food relations, but few on population-behavior relations, very few on food-behavior relations, and hardly any on all three aspects together.

We thank D. Jenkins and A.N. Lance for helpful comments on the manuscript, and acknowledge the encouragement and support given to our work by Professor V.C. Wynne-Edwards.