The SLOSS debate can only be resolved by considering the optimal spatial configuration of a nature‐reserve system. Only when target species have been identified by such considerations can the size of the constituent reserves be determined. We explored two null models for a spatial configuration of reserves in the Cape Floristic Region, South Africa, based on the distribution of species in the family Proteaceae (Angiospermae: Rosidae). In the first model, reserves (12 × 13 km grid squares) were assigned at random for comparison with existing, proposed, and theoretically ideal configurations. In the second model, the theoretically ideal reserve configuration was constructed using the first model as a preassigned configuration. Two methods were used to iteratively select a reserve from the grid system: richness of unprotected species (species‐richness algorithm), and the sum of the rarity indexes for each unprotected species (rarity algorithm). Both algorithms yielded configurations requiring fewer reserves than those contained in proposed or existing configurations, although neither algorithm was perfect. The existing reserve configuration performed no better than the random model, assuming that the principal goal is protection of all species. We confirm that the best approach to designing a reserve configuration that maximizes the protection of species richness is to identify areas of high endemism and richness within particular biogeographical regions.

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Rates of C02 production by breeding Jackass Penguins (mean mass, 3170 g) were measured by using doubly labeled water. Time budgets were estimated from behavioral observations, and energy budgets were calculated for a typical 2-d period of 24 h sitting on a nest and 24 hoff the nest (which includes 9 h foraging at sea). Distances traveled at sea were determined by using speed/ time meters harnessed to five birds containing doubly labeled water, and these measurements were used to calculate the energetic costs of swimming.Field metabolic rates (as C02 production) averaged 0.991 mL· g·L h-1 , or (in energy units) 3890 kJ·penguin-1.2 d-1 • Energy expenditures were 1.7 times the standard metabolic rate (SMR) while brooding, 6.6 x SMR while foraging, 9.8 x SMR while swimming underwater, and 2.6 x SMR integrated over a 2-d period. Penguins spent :::::48% of their energy budget and 19% of their time budget to obtain food. Foraging efficiency (the metabolizable energy gained while foraging + the energy used during foraging) was 2.

The indigenous angiosperm tree flora (1,340 species) of southern Africa was analysed for type, size and colour of fruits and class of biotic dispersal agent (consumer). Species producing fleshy (drupes and berries) and dry (pods, capsules and nuts) fruits account for 52% and 47%, respectively, of the flora. The flora contains about 2.5 times as many berry-producing as drupe-producing species. Based on a log-linear model, fruit type, consumer and fruit size are dependent statistically on each other, whereas fruit colour depends on both fruit size and consumer type acting independently of each other. Drupes and berries are consumed by birds and mammals, with berries being favoured by both birds and mammals. At least 23% (307 species) of the flora apparently depends predominantly on birds for seed dispersal. Drupes and berries favoured by birds tend to be small and brightly coloured (red or black), whereas those eaten mainly by mammals tend to be large and dull (yellow or green). Relatively few fleshy fruits are brown. Pods, capsules and nuts tend to be brown or green. Birds apparently tend to avoid eating green fruits. The notion that green coloration has evolved to enhance crypsis and/or to signal unpalatability in unripe fruit to reduce premature exploitation is questioned. Green as a cryptic colour is incompatible with the demonstrated mammalian selection of this colour, while to function aposematically a stronger contrast colour may be required.

We measured the field metabolic rate (FMR) and water influx rate (WIR) of the largest species of bird, the Ostrich (Struthio camelus), which lives in the Namib desert, one of the driest regions on earth. Along with doubly—labeled water (DLW) measurements of FMR and WIR, we examined the availability of plants in various habitats, the plants selected by Ostriches, and the daily activity patterns of these birds. During 6—8 d periods, adult Ostriches (88.25 kg) had an FMR of 18 040 kJ/d, while subadult birds (50.75 kg) metabolized energy at a rate of 15 428 kJ/d. Adult energy expenditure was 26% lower than predicted, but subadults had a FMR nearly equivalent to expectation, suggesting that adults may be more efficient at acquiring resources. Conclusions remain tentative because data for the Ostrich exceed previous data used for allometric equations by almost an order of magnitude. Gravel and stoney plains together accounted for 84% of the study area, whereas washes occupied °1%. Vegetation cover was sparse in all habitats, varying between 7 and 19% in most areas, but comprising °15% along drainage lines. Ostriches foraged on gravel plains nearly 65% of their daytime hours and 25.5% of their day in washes. They consumed a narrow range of green plants with Monechma arenicola, Schmidita kalahariensis, Blepharis spp., Trianthema triquetra, and Dicoma capensis representing the principal items in the diet. From a time—activity budget, Ostriches spent 7.5 h of their 24—h day walking, and roosted at night for 11.5 h. Transport between food patches accounted for 62.2% of FMR while nighttime rest was 19.0%. Preening and other maintenance behaviors were responsible for <1% of the Ostriches' energy budget. Ostriches had a frugal water economy when compared to other nonpasserine birds, with both subadults and adults having lower WIRs than predicted. Values for WIR were higher than allometric predictions based on four other desert birds previously studied, but because Ostriches are two orders of magnitude larger in body mass, firm conclusions await further data. Calculations of the water economy index (WEI), the ration of water influx to FMR (in millilitres of water kilojoule), showed that Ostriches conserved water like smaller desert birds. Four species of desert birds had WEI values averaging 0.16 mL/kJ; values of the Ostrich averaged 0.17 mL/kJ. An itemized water budget suggested that adults did not drink during the periods of observation, while water intake by subadults averaged 729 ml/d. This suggests that adults may have lower minimum water requirements than subadults. Combining available data for FMR and WIR with data for the Ostrich, we constructed new allometric equations that nearly span the entire range of bird size and include 62 species of birds.