Field Metabolic Rate and Food Requirement Scaling in Mammals and Birds

Abstract

Abstra~t. Field m~tabolic rates (FMRs or HF), all measured using doubly labeled water, o~ 23 species of eut_henan mammals, 13 species of marsupial mammals, and 25 species of birds were sumi?anzed and ana_lyzed allometrically (log 10 -log, 0 regressions). FMR is strongly correlated with body mass m each of these groups. FMR scales differently than does basal or standard met~bol~c rate in eutherians (FMR slope= 0.81) and marsupials (FMR ~lope= 0.58J, but not m birds (FMR slope= 0.64 overall, but 0.75 in passerines and 0.75 mall other birds). Medium-sized (240-550 g) eutherians, marsupials, and birds have similar FMRs, and these are ~ 1 7 times as high as FMRs of like-sized ectothermic vertebrates ~uch as iguanid lizards. Fo~ endothermic vertebrates, the energy cost of surviving in nature Is. enormous compar.ed With that for ectotherms. Within the eutherians, marsupials, or b~rds, FMR sca!es differently for the following subgroups: rodents, passerine birds, her-bivor~us euther~ans, herbivorous marsupials, desert eutherians, desert birds, and seabirds. Equat~ons are give~ for use in predicting daily and annual FMR and food requirement of a species of terrestnal vertebrate, given its body mass.

The digestive morphophysiology of wild, free-living, giraffes

“…The minimum amount of browse that must be consumed by giraffes to meet FMR can be calculated by dividing the calculated FMR (kj/day) for each giraffe by the metabolizable energy content of browse (Nagy, 1987). Two analyses of metabolizable energy (ME) content of browse eaten by wild giraffe have been made, one in the Serengeti by Pellew (1984A) and the other in the Timbavati Nature Reserve by Hall-Martin & Basson (1975 Home range (HR) size (km 2 ).…”

Effects of predation by sea ducks on clam abundance in soft-bottom intertidal habitats

“…The amount of energy consumed over the winter period by scoters in our sample plots was independently estimated as follows: energy consumed = (field metabolic rate/ energy assimilation rate) × number of bird days (Larsen & Guillemette 2000). Field metabolic rate (FMR) was calculated using allometric estimates for seabirds (Nagy 1987), where log FMR (kJ d -1 ) = 0.904 + 0.704 × log body mass (g).…”

“…The amount of energy consumed over the winter period by scoters, based on independent allometric estimates (Nagy 1987), was approximately 37 × 10 6 kJ for all 6 sample plots combined. Using a clam length of 31 mm, which is the average length of all Manila, varnish, and Pacific littleneck clams sampled, our estimate of number of clams consumed by scoters (3.67 × 10 6 clams) converts to approximately 26 × 10 6 kJ.…”

Body size, energy consumption and allometric scaling: a new dimension in the diversity?stability debate

“…(14) suggests either a constant biomass B ∝ M 0 (if α = 2/3, as is the case in birds, for example (Nagy, 1987;Dodds et al, 2001)) or a decrease of biomass at a rate of B ∝ M 1−(1/3+α) (if α > 2/3).…”

“…Damuth (1981Damuth ( , 1987 pointed out that in mammals and several other higher taxa D decreases proportionally to M −0.75 , where M is body mass. Assuming that metabolic rate R increases as M 0.75 (Kleiber, 1932;Hemmingsen, 1960;Nagy, 1987), Damuth put forward the idea of energetic equivalence of species, i.e., that every species consumes the same amount of energy per unit time per unit area irrespective of its body size. This result has been widely discussed and tested against different types of data (Peters and Wassenberg, 1983;Brown and Maurer, 1986;Robinson and Redford, 1986;Lawton, 1990;Marquet et al, 1990;Nee et al, 1991;Blackburn et al, 1993;Damuth, 1993;Greenwood et al, 1996;Navarrete and Menge, 1997;Knouft, 2002).…”