Water metabolism in the Namib Desert Golden Mole, Eremitalpa granti namibensis (Chrysochloridae)

Energetics of burrowing, running, and free‐living in the Namib Desert golden mole ( Eremitalpa namibensis )

“…Our value of water turnover (2.27 ml d -1 ) falls between the means that Fielden et al (1990b) measured in the ®eld (1.73 ml d -1 ) and in the laboratory (3.15 ml d -1 ), and is only 59% of the expected ®eld water turnover of 3.87 ml d -1 for a 20.6 g mammal (Nagy & Peterson, 1988). Low rates of water loss are presumably associated with low ventilation rates required for low metabolic rates, a low body temperature, and high humidity underground.…”

“…Assuming that this mainly fat and protein diet yields 25 mg of metabolic water per kJ of energy metabolized (see Withers, 1992, supplement 4±1), the ®eld metabolic rate of 12.46 kJ d -1 would be associated with a metabolic water production of 312 mg d -1 . This ef®ciency is near that of Namib moles in the laboratory on a diet of meal worm larvae (Fielden et al, 1990b), and within the range of about 60±80% in other insectivorous mammals (Nagy et al, 1978) and birds (Krebs & Avery, 1984;Bryant & Bryant, 1988), but is more than the value of about 50% reported for an anteating lizard, Moloch horridus (Withers & Dickman, 1995). We collected 160 dune termites and found them to average 1.37 mg wet mass, 0.39 mg dry mass, 0.98 mg water, and 20.5 J mg -1 dry mass.…”

Energetics of burrowing, running, and free‐living in the Namib Desert golden mole ( Eremitalpa namibensis )

“…Our value of water turnover (2.27 ml d -1 ) falls between the means that Fielden et al (1990b) measured in the ®eld (1.73 ml d -1 ) and in the laboratory (3.15 ml d -1 ), and is only 59% of the expected ®eld water turnover of 3.87 ml d -1 for a 20.6 g mammal (Nagy & Peterson, 1988). Low rates of water loss are presumably associated with low ventilation rates required for low metabolic rates, a low body temperature, and high humidity underground.…”

“…Assuming that this mainly fat and protein diet yields 25 mg of metabolic water per kJ of energy metabolized (see Withers, 1992, supplement 4±1), the ®eld metabolic rate of 12.46 kJ d -1 would be associated with a metabolic water production of 312 mg d -1 . This ef®ciency is near that of Namib moles in the laboratory on a diet of meal worm larvae (Fielden et al, 1990b), and within the range of about 60±80% in other insectivorous mammals (Nagy et al, 1978) and birds (Krebs & Avery, 1984;Bryant & Bryant, 1988), but is more than the value of about 50% reported for an anteating lizard, Moloch horridus (Withers & Dickman, 1995). We collected 160 dune termites and found them to average 1.37 mg wet mass, 0.39 mg dry mass, 0.98 mg water, and 20.5 J mg -1 dry mass.…”

Energetics of burrowing, running, and free-living in the Namib Desert golden mole (Eremitalpa namibensis)

“…It follows that they ingested about 15.9 kJ d -1 , and their assimilation ef®ciency was 12.46/15.9 or 79%. This ef®ciency is near that of Namib moles in the laboratory on a diet of meal worm larvae (Fielden et al, 1990b), and within the range of about 60±80% in other insectivorous mammals (Nagy et al, 1978) and birds (Krebs & Avery, 1984;Bryant & Bryant, 1988), but is more than the value of about 50% reported for an anteating lizard, Moloch horridus (Withers & Dickman, 1995).…”

Movement seasonality in a desert-dwelling bat revealed by miniature GPS loggers

“…Although independence from open water sources in deserts has been found for species in various taxa including mammals, e.g. rodents [58, 59], reports of this behaviour for bats in the wild are limited to field observations [21] (but see [60] for tests in captivity), and further investigations are needed.…”

Energetics of burrowing, running, and free‐living in the Namib Desert golden mole ( Eremitalpa namibensis )

“…Our value of water turnover (2.27 ml d -1 ) falls between the means that Fielden et al (1990b) measured in the ®eld (1.73 ml d -1 ) and in the laboratory (3.15 ml d -1 ), and is only 59% of the expected ®eld water turnover of 3.87 ml d -1 for a 20.6 g mammal (Nagy & Peterson, 1988). Low rates of water loss are presumably associated with low ventilation rates required for low metabolic rates, a low body temperature, and high humidity underground.…”

“…Assuming that this mainly fat and protein diet yields 25 mg of metabolic water per kJ of energy metabolized (see Withers, 1992, supplement 4±1), the ®eld metabolic rate of 12.46 kJ d -1 would be associated with a metabolic water production of 312 mg d -1 . This ef®ciency is near that of Namib moles in the laboratory on a diet of meal worm larvae (Fielden et al, 1990b), and within the range of about 60±80% in other insectivorous mammals (Nagy et al, 1978) and birds (Krebs & Avery, 1984;Bryant & Bryant, 1988), but is more than the value of about 50% reported for an anteating lizard, Moloch horridus (Withers & Dickman, 1995). We collected 160 dune termites and found them to average 1.37 mg wet mass, 0.39 mg dry mass, 0.98 mg water, and 20.5 J mg -1 dry mass.…”

Energetics of burrowing, running, and free-living in the Namib Desert golden mole (Eremitalpa namibensis)

“…It follows that they ingested about 15.9 kJ d -1 , and their assimilation ef®ciency was 12.46/15.9 or 79%. This ef®ciency is near that of Namib moles in the laboratory on a diet of meal worm larvae (Fielden et al, 1990b), and within the range of about 60±80% in other insectivorous mammals (Nagy et al, 1978) and birds (Krebs & Avery, 1984;Bryant & Bryant, 1988), but is more than the value of about 50% reported for an anteating lizard, Moloch horridus (Withers & Dickman, 1995).…”

Movement seasonality in a desert-dwelling bat revealed by miniature GPS loggers

“…Although independence from open water sources in deserts has been found for species in various taxa including mammals, e.g. rodents [58, 59], reports of this behaviour for bats in the wild are limited to field observations [21] (but see [60] for tests in captivity), and further investigations are needed.…”

Energetics of burrowing, running, and free‐living in the Namib Desert golden mole ( Eremitalpa namibensis )

“…Our value of water turnover (2.27 ml d -1 ) falls between the means that Fielden et al (1990b) measured in the ®eld (1.73 ml d -1 ) and in the laboratory (3.15 ml d -1 ), and is only 59% of the expected ®eld water turnover of 3.87 ml d -1 for a 20.6 g mammal (Nagy & Peterson, 1988). Low rates of water loss are presumably associated with low ventilation rates required for low metabolic rates, a low body temperature, and high humidity underground.…”

“…Assuming that this mainly fat and protein diet yields 25 mg of metabolic water per kJ of energy metabolized (see Withers, 1992, supplement 4±1), the ®eld metabolic rate of 12.46 kJ d -1 would be associated with a metabolic water production of 312 mg d -1 . This ef®ciency is near that of Namib moles in the laboratory on a diet of meal worm larvae (Fielden et al, 1990b), and within the range of about 60±80% in other insectivorous mammals (Nagy et al, 1978) and birds (Krebs & Avery, 1984;Bryant & Bryant, 1988), but is more than the value of about 50% reported for an anteating lizard, Moloch horridus (Withers & Dickman, 1995). We collected 160 dune termites and found them to average 1.37 mg wet mass, 0.39 mg dry mass, 0.98 mg water, and 20.5 J mg -1 dry mass.…”

Energetics of burrowing, running, and free-living in the Namib Desert golden mole (Eremitalpa namibensis)

“…It follows that they ingested about 15.9 kJ d -1 , and their assimilation ef®ciency was 12.46/15.9 or 79%. This ef®ciency is near that of Namib moles in the laboratory on a diet of meal worm larvae (Fielden et al, 1990b), and within the range of about 60±80% in other insectivorous mammals (Nagy et al, 1978) and birds (Krebs & Avery, 1984;Bryant & Bryant, 1988), but is more than the value of about 50% reported for an anteating lizard, Moloch horridus (Withers & Dickman, 1995).…”

Movement seasonality in a desert-dwelling bat revealed by miniature GPS loggers

“…Although independence from open water sources in deserts has been found for species in various taxa including mammals, e.g. rodents [58, 59], reports of this behaviour for bats in the wild are limited to field observations [21] (but see [60] for tests in captivity), and further investigations are needed.…”