Do metabolism and contour plumage insulation vary in response to seasonal energy bottlenecks in superb fairy-wrens?

2006 ◽  
Vol 54 (1) ◽  
pp. 23 ◽  
Author(s):  
Alan Lill ◽  
Jeffrey Box ◽  
John Baldwin
Keyword(s):  
Critical Temperature ◽  
Metabolic Rate ◽  
Thermal Conductance ◽  
Whole Body ◽  
Ambient Temperatures ◽  
The North ◽  
General Metabolism ◽  
Lower Critical Temperature ◽  
Heat Conservation ◽  
Low Altitude

Many small birds living at mid-to-high latitudes in the North Temperate Zone display seasonal increases in general metabolism and plumage insulation. We examined whether superb fairy-wrens at low altitude in temperate Australia, where winter is milder and the winter–spring transition less pronounced, exhibited similar adjustments. Their oxygen-consumption rate at ambient temperatures in and below their thermoneutral range was measured overnight in winter, spring and summer. Contour plumage mass was also compared in individuals caught in all seasons of the year. Resting-phase metabolic rate in the thermoneutral zone did not vary seasonally. The relationship between ambient temperature and whole-body metabolic rate below lower critical temperature differed in summer and winter, but the regression for spring did not differ from those for summer or winter. Plumage mass was greater (4.04% v. 2.64% of body mass) and calculated whole-bird wet thermal conductance lower (1.55 v. 2.24 mL O2 bird–1 h–1 °C–1) in winter than in summer. Enhanced plumage insulation could have improved heat conservation in autumn and winter. No increase in standard metabolism occurred in winter, perhaps because this season is relatively mild at low altitude in temperate Australia. However, superb fairy-wrens at 37°S operated below their predicted lower critical temperature for most of winter and the early breeding season, so they have presumably evolved as yet unidentified mechanisms for coping with the energy bottlenecks encountered then.

scholarly journals Laboratory Metabolism of Incubating Semipalmated Plovers

The Condor ◽  
2006 ◽  
Vol 108 (4) ◽  
pp. 966-970
Author(s):  
Mark Williamson ◽  
Joseph B. Williams ◽  
Erica Nol
Keyword(s):  
Critical Temperature ◽  
Metabolic Rate ◽  
Breeding Season ◽  
Basal Metabolic Rate ◽  
Low Temperatures ◽  
Thermal Conductance ◽  
Basal Metabolism ◽  
The Arctic ◽  
Lower Critical Temperature ◽  
Metabolic Data

Abstract Abstract The Semipalmated Plover (Charadriussemipalmatus), anarctic-nesting migratory shorebird, regularlyencounters low temperatures during the breedingseason. We measured the basal metabolism of adultsduring incubation at Churchill, Manitoba, Canada todetermine basal metabolic rate (BMR),lower critical temperature(Tlc), total evaporative waterloss (TEWL), and dry thermal conductance(Cm). BMR and Tlcwere 47.4 kJ day−1and 23.3°C, respectively, TEWL was2.5 mL H2O−d,and Cm was1.13 mW g−1 °C−1.Measured BMR and Tlc were consistentwith high values found for other shorebird speciesbreeding in the Arctic, while Cm was18% higher than predicted from allometricequations. These metabolic data suggest thatSemipalmated Plovers are adapted to balance therequirements of incubation against energetic andthermoregulatory demands in the Arctic, especiallyin harsh early breeding season conditions.

The heat production of oiled mallards and scaup

1973 ◽  
Vol 51 (1) ◽  
pp. 27-31 ◽  
Author(s):  
E. H. McEwan ◽  
A. F. C. Koelink
Keyword(s):  
Critical Temperature ◽  
Metabolic Rate ◽  
Ambient Temperature ◽  
Heat Loss ◽  
Heat Production ◽  
Normal Values ◽  
Thermal Conductance ◽  
Water Repellency ◽  
Regression Analyses ◽  
Lower Critical Temperature

A measure of the thermal conductance of the plumage of normal and oiled ducks was determined from regression analyses that related metabolic rate and ambient temperature. The heat loss of heavily oiled mallards and scaup was 1.7 and 2 times greater than their normal values, respectively. Oiling not only tended to increase the basal heat production, but also shifted the lower critical temperature from 12 to 25C. Attempts to rehabilitate the scaup after oiling and cleaning were rarely successful because of plumage deterioration and the loss of water repellency.

Thermoregulation in the only nocturnal simian: the night monkey Aotus trivirgatus

1981 ◽  
Vol 240 (3) ◽  
pp. R156-R165 ◽  
Author(s):  
Y. Le Maho ◽  
M. Goffart ◽  
A. Rochas ◽  
H. Felbabel ◽  
J. Chatonnet
Keyword(s):  
Critical Temperature ◽  
Metabolic Rate ◽  
Response Pattern ◽  
Thermal Environment ◽  
Resting Metabolic Rate ◽  
Thermal Conductance ◽  
Open Circuit ◽  
The Body ◽  
Thermoneutral Zone ◽  
Lower Critical Temperature

The night monkey, a tropical monkey, is the only nocturnal simian; its thermoregulation was studied for comparison with other nocturnal or diurnal primates and other tropical mammals. Resting metabolic rate was 2.6 W (closed-circuit method) and 2.8 W (open-circuit method), 24 and 18% below the value predicted from body mass. The thermoneutral zone was very narrow; the lower critical temperature (LCT) was 28 degrees C and the upper critical temperature (UCT) was 30 degrees C. The body temperature (Tb) was at its minimum (38 degrees C) at an ambient temperature (Ta) of 25 degrees C, thus below the LCT. At low Ta, the increase in metabolic rate (MR) was smaller than predicted by the Scholander model, since MR intersected to a Ta 13 degrees C above Tb when extrapolated to MR = 0; this was attributed to a decrease of body surface area by behavior. The thermal conductance at the LCT was low: 2.3 W . m-2 . degrees C-1. Above the UCT, panting was the major avenue of heat loss. The response pattern of nocturnal habits, low resting metabolic rate, low thermal conductance, and panting in the night monkey, unique among simians, is found in many other mammals of tropical and hot desert habitats; it may be considered as an alternative adaptation to the thermal environment.

Influence of wind speed on sage grouse metabolism

1995 ◽  
Vol 73 (4) ◽  
pp. 749-754 ◽  
Author(s):  
Mark H. Sherfy ◽  
Peter J. Pekins
Keyword(s):  
Critical Temperature ◽  
Wind Speed ◽  
Metabolic Rate ◽  
Centrocercus Urophasianus ◽  
Standard Metabolic Rate ◽  
Sage Grouse ◽  
Ambient Temperatures ◽  
Wind Speeds ◽  
Lower Critical Temperature ◽  
Wind Measurements

We measured the effect of wind speed on the metabolic rate of six adult sage grouse (Centrocercus urophasianus) with indirect respiration calorimetry at ambient temperatures above, near, and below the lower critical temperature. There was a significant effect (P < 0.05) of temperature on metabolic rate at all wind speeds, and a significant effect (P < 0.05) of wind speed on metabolic rate for temperatures ≤ 0 °C. Wind speed had a more pronounced effect on metabolism at temperatures below the lower critical temperature for sage grouse. Metabolic rates measured at wind speeds of ≥ 1.5 m/s were significantly higher than those measured at wind speeds < 1.5 m/s. Multiple regression analysis of wind speed (u; m/s) and temperature (Ta; °C) on metabolism (MR; mL O2∙g−1∙h−1) yielded the equation MR = 0.0837 (u) − 0.0248 (Ta) + 0.5444. The predicted cost of thermoregulation at conditions of −5 °C and u = 1.5 m/s was about 1.5× standard metabolic rate; half the increase was due to wind. Measurements of wind speed in sagebrush (Artemisia spp.) stands indicate that such habitat effectively reduces wind speed to < 1.5 m/s. Microhabitat value should be recognized in the management of sagebrush stands.

Regulation of metabolic rate in Svalbard and Norwegian reindeer

1984 ◽  
Vol 247 (5) ◽  
pp. R837-R841 ◽  
Author(s):  
K. J. Nilssen ◽  
J. A. Sundsfjord ◽  
A. S. Blix
Keyword(s):  
Body Weight ◽  
Critical Temperature ◽  
Food Intake ◽  
Metabolic Rate ◽  
Seasonal Changes ◽  
Serum Levels ◽  
Physiological Adaptation ◽  
Conservation Of Energy ◽  
Winter Food ◽  
Lower Critical Temperature

Food intake, body weight, serum levels of triiodothyronine (T3) and free thyroxine (FT4), and metabolic rate were measured at intervals in Svalbard (SR) and Norwegian (NR) reindeer. From summer to winter food intake decreased 57 (SR) and 55% (NR), while body weight decreased 8.6 (SR) and 3.8% (NR). In SR T3 and FT4 changed seasonally, whereas this was only evident for T3 in NR. Resting (standing) metabolic rate (RMR) in winter was 1.55 (SR) and 2.05 W X kg-1 (NR), lower critical temperature (TLC) being -50 (SR) and -30 degrees C (NR). RMR in summer was 2.15 (SR) and 2.95 W X kg-1 (NR), TLC being -15 (SR) and 0 degrees C (NR). Seasonal changes in T3 and FT4 did not coincide with changes in food intake or RMR in either SR or NR. RMR did, however, correlate with food intake. This indicates that seasonal changes in RMR are due to the thermic effects of feeding and represent no physiological adaptation aimed at conservation of energy during winter.

Energy expenditure for thermoregulation and locomotion in emperor penguins

1976 ◽  
Vol 231 (3) ◽  
pp. 903-912 ◽  
Author(s):  
B Pinshow ◽  
MA Fedak ◽  
DR Battles ◽  
K Schmidt-Nielsen
Keyword(s):  
Metabolic Rate ◽  
Energy Requirement ◽  
Thermal Conductance ◽  
Standard Metabolic Rate ◽  
High Energy ◽  
Breeding Cycle ◽  
Emperor Penguin ◽  
Energy Reserves ◽  
Ambient Temperatures ◽  
Emperor Penguins

During the antarctic winter emperor penguins (Aptenodytes forsteri) spend up to four mo fasting while they breed at rookeries 80 km or more from the sea, huddling close together in the cold. This breeding cycle makes exceptional demands on their energy reserves, and we therefore studied their thermoregulation and locomotion. Rates of metabolism were measured in five birds (mean body mass, 23.37 kg) at ambient temperatures ranging from 25 to -47 degrees C. Between 20 and -10 degrees C the metabolic rate (standard metabolic rate (SMR)) remained neraly constant, about 42.9 W. Below -10 degrees C metabolic rate increased lineraly with decreasing ambient temperature and at -47 degrees C it was 70% above the SMR. Mean thermal conductance below -10 degrees C was 1.57 W m-2 degrees C-1. Metabolic rate during treadmill walking increased linearly with increasing speed. Our data suggest that walking 200 km (from the sea to the rookery and back) requires less than 15% of the energy reserves of a breeding male emperor penguin initially weighing 35 kg. The high energy requirement for thermoregulation (about 85%) would, in the absence of huddling, probably exceed the total energy reserves.

The metabolic rate and thermal conductance of the eastern barred bandicoot (Perameles gunnii) at different ambient temperatures

2003 ◽  
Vol 51 (6) ◽  
pp. 603 ◽  
Author(s):  
M. P. Ikonomopoulou ◽  
R. W. Rose
Keyword(s):  
Oxygen Consumption ◽  
Body Temperature ◽  
Metabolic Rate ◽  
Thermal Conductance ◽  
The Body ◽  
High Metabolic Rate ◽  
Ambient Temperatures ◽  
Reduced Body ◽  
Thermoneutral Zone ◽  
Reproductive Females

We investigated the metabolic rate, thermoneutral zone and thermal conductance of the eastern barred bandicoot in Tasmania. Five adult eastern barred bandicoots (two males, three non-reproductive females) were tested at temperatures of 3, 10, 15, 20, 25, 30, 35 and 40°C. The thermoneutral zone was calculated from oxygen consumption and body temperature, measured during the daytime: their normal resting phase. It was found that the thermoneutral zone lies between 25°C and 30°C, with a minimum metabolic rate of 0.51 mL g–1 h–1 and body temperature of 35.8°C. At cooler ambient temperatures (3–20°C) the body temperature decreased to approximately 34.0°C while the metabolic rate increased from 0.7 to 1.3 mL g–1�h–1. At high temperatures (35°C and 40°C) both body temperature (36.9–38.7°C) and metabolic rate (1.0–1.5 mL g–1 h–1) rose. Thermal conductance was low below an ambient temperature of 30°C but increased significantly at higher temperatures. The low thermal conductance (due, in part, to good insulation, a reduced body temperature at lower ambient temperatures, combined with a relatively high metabolic rate) suggests that this species is well adapted to cooler environments but it could not thermoregulate easily at temperatures above 30°C.

The ontogeny of metabolic rate and thermoregulatory capabilities of northern fur seal, Callorhinus ursinus, pups in air and water

2000 ◽  
Vol 203 (6) ◽  
pp. 1003-1016 ◽  
Author(s):  
M.J. Donohue ◽  
D.P. Costa ◽  
M.E. Goebel ◽  
J.D. Baker
Keyword(s):  
Metabolic Rate ◽  
Developmental Stages ◽  
Resting Metabolic Rate ◽  
Thermal Conductance ◽  
Open Circuit ◽  
Whole Body ◽  
Callorhinus Ursinus ◽  
Metabolic Rates ◽  
Northern Fur Seal ◽  
Fur Seal

Young pinnipeds, born on land, must eventually enter the water to feed independently. The aim of this study was to examine developmental factors that might influence this transition. The ontogeny of metabolic rate and thermoregulation in northern fur seal, Callorhinus ursinus, pups was investigated at two developmental stages in air and water using open-circuit respirometry. Mean in-air resting metabolic rate (RMR) increased significantly from 113+/−5 ml O(2)min(−)(1) (N=18) pre-molt to 160+/−4 ml O(2)min(−)(1) (N=16; means +/− s.e.m.) post-molt. In-water, whole-body metabolic rates did not differ pre- and post-molt and were 2.6 and 1.6 times in-air RMRs respectively. Mass-specific metabolic rates of pre-molt pups in water were 2.8 times in-air rates. Mean mass-specific metabolic rates of post-molt pups at 20 degrees C in water and air did not differ (16.1+/−1.7 ml O(2)min(−)(1)kg(−)(1); N=10). In-air mass-specific metabolic rates of post-molt pups were significantly lower than in-water rates at 5 degrees C (18.2+/−1.1 ml O(2)min(−)(1)kg(−)(1); N=10) and 10 degrees C (19.4+/−1.7 ml O(2)min(−)(1)kg(−)(1); N=10; means +/− s.e.m.). Northern fur seal pups have metabolic rates comparable with those of terrestrial mammalian young of similar body size. Thermal conductance was independent of air temperature, but increased with water temperature. In-water thermal conductance of pre-molt pups was approximately twice that of post-molt pups. In-water pre-molt pups matched the energy expenditure of larger post-molt pups while still failing to maintain body temperature. Pre-molt pups experience greater relative costs when entering the water regardless of temperature than do larger post-molt pups. This study demonstrates that the development of thermoregulatory capabilities plays a significant role in determining when northern fur seal pups enter the water.

Further studies on the heat production and effective lower critical temperature of early-weaned pigs under commercial conditions of feeding and management

1984 ◽  
Vol 39 (2) ◽  
pp. 283-290 ◽  
Author(s):  
K. J. McCracken ◽  
R. Gray
Keyword(s):  
Critical Temperature ◽  
Heat Production ◽  
Thermal Conductance ◽  
Open Circuit ◽  
Weaned Pigs ◽  
Respiration Chamber ◽  
Lower Critical Temperature ◽  
The Mean ◽  
The Difference ◽  
Practical Implications

ABSTRACTIn two separate experiments pigs were weaned at 14 or 28 days and heat production was determined in an open-circuit respiration chamber at temperatures above and below the lower critical temperature (Tcl) at intervals during the post-weaning period.With 14-day weaned pigs the mean 24 h heat production above Tc1 averaged 267, 328, 474 and 554 kJ/h per m2 at 3, 9, 15 and 21 days post weaning respectively. The mean thermal conductance (H/AT, kJ/h per m2 per °ΔT, where H is total heat production, m2 is the surface area calculated as 0·097 M kg0·633 and °Δ is the difference between rectal temperature, taken at 39°, and air temperature) below TC1 was calculated as 20·5, 20·1, 23·1 and 24·2 at 17, 23, 29 and 35 days of age respectively and the corresponding values for Tc1 were 25·9, 23·0, 18·4 and 16·0°C.With 28-day weaned pigs the mean 24 h heat production above Tc1 averaged 280, 361 and 445 kJ/h per m2 at 3, 9 and 15 days post weaning. The calculated values for H/ΔT were 19·7, 20·8 and 21·6 and the corresponding values of Tcl were 24·8, 21·7, and 18·8°C at 31, 37 and 43 days of age respectively.The results are discussed in relation to previous studies on 10-day and 28-day weaned pigs and in relation to the practical implications for pigs weaned into controlled-environment accommodation.

Thermoregulatory, metabolic and ventilatory physiology of the eastern barred bandicoot (Perameles gunnii)

2006 ◽  
Vol 54 (1) ◽  
pp. 9 ◽  
Author(s):  
Alexander N. Larcombe ◽  
Philip C. Withers ◽  
Stewart C. Nicol
Keyword(s):  
Body Temperature ◽  
Metabolic Rate ◽  
Basal Metabolic Rate ◽  
Extraction Efficiency ◽  
Thermal Conductance ◽  
Minute Volume ◽  
Evaporative Water ◽  
Ambient Temperatures ◽  
Ventilatory Parameters ◽  
High Basal Metabolic Rate

Thermoregulatory, metabolic and ventilatory parameters measured for the Tasmanian eastern barred bandicoot (Perameles gunnii) in thermoneutrality (ambient temperature = 30°C) were: body temperature 35.1°C, basal metabolic rate 0.55 mL O2 g–1 h–1, wet thermal conductance 2.2 mL O2 g–1 h–1 °C–1, dry thermal conductance 1.4 J g–1 h–1 °C–1, ventilatory frequency 24.8 breaths min–1, tidal volume 9.9 mL, minute volume of 246 mL min–1, and oxygen extraction efficiency 22.2%. These physiological characteristics are consistent with a cool/wet distribution, e.g. high basal metabolic rate (3.33 mL O2 g–0.75 h–1) for thermogenesis, low thermal conductance (0.92 J g–1 h–1 °C–1 at 10°C) for heat retention and intolerance of high ambient temperatures (≥35°C) with panting, hyperthermia and high total evaporative water loss (16.9 mg H2O g–1 h–1).

Sign in / Sign up

Export Citation Format

Share Document