Lindeman and the Ecological Efficiency of Wolves

Lindeman introduced three themes into ecology. (i) He explained the Eltonian pyramid by his paradigm of energy flow. (ii) He introduced the hypothesis that succession proceeds in directions that would be energetically efficient. (iii) He suggested that characteristic efficiencies of energy transfer would be found between trophic levels. The theme of trophic level transfer efficiency (Lindeman efficiency) has been little followed except in studies of the producer trophic level. The vegetation of even mesic sites converts fuel of sunlight to potential fuel of primary consumers at less than 2% efficiency. This suggests that the stability of most ecosystems is set by physical processes that dissipate the remaining 98% of incident energy. No estimates of Lindeman efficiencies of natural animal trophic levels appear to have been made except those, like Lindeman's own, that are flawed by the use of turnover times. Laboratory studies of small animals in systems where a single species occupies a trophic level are responsible for the general belief that animal trophic levels may be approximately 10% efficient. The Isle Royale wolf-moose system may be compared to a laboratory microcosm in which a single-species population of small animals is maintained at an approximate steady-state. Energy fluxes into the moose and wolf populations are calculated from caloric yields of corpses added to respiration. The ecological (Lindeman) efficiency of the wolf trophic level is found to approximate 1.3%. This Lindeman efficiency compares with the production efficiency of the moose herd of 11.9%, showing that wolves capture only a small portion of the energy theoretically available to them. It is argued that Lindeman efficiencies of these low orders may be typical of large carnivores and possibly of the "hunting" type of herbivore. Home range may be an indirect measure of Lindeman efficiency.