Introduction

As I have already shown in Chapters 2–4, burrowing serves a diversity of functions, including denning and rearing of young, socialization, shelter from predators and protection from climatic stress, caching of food (Chapter 5), access to below–ground food sources, and sites for seasonal hibernation/estivation (Collias and Collias 1976; Von Frisch 1983; Hansell 1984, 1993; Andersen 1987; A. Meadows 1991; P.S. Meadows 1991; Meadows and Meadows 1991b). In the broadest sense, burrowing encompasses features ranging from shallow daybeds to extensive tunnel complexes. The process of burrowing directly affects geomorphic processes because it bioturbates surface and subsurface sediment, leads to sediment deposition in the form of surface spoil heaps, and may create distinctive landforms. Indirectly, burrowing produces profound geomorphic results in fashions similar to those already examined for other animals: through its influence on soil texture and structure, fertility, and infiltration capacity (cf. Abaturov 1972; Hirsch, Stubbendieck, and Case 1984; Tadzhiyev and Odinoshoyev 1987; Dmitriyev 1989; Dmitriyev, Khudyakov, and Galsan 1989), and the resulting changes both in production of vegetation cover (Del Moral 1984; Gessaman and MacMahon 1984; Huntly 1987; Moorhead, Fisher, and Whitford 1988; Minta and Clark 1989; Peart 1989; Mun and Whitford 1990), and surface runoff and erosion (Turcek 1963; Ursic and Esher 1988; Bykov and Sapanov 1989; Laundre 1993). This chapter examines the direct and indirect geomorphic effects brought about by burrowing. Special emphasis is placed on describing the landforms created by burrowing, and on quantifying the amounts of sediment displaced and entered into hillslope debris cascades.