The stoichiometric approach in determining total evaporative water loss and the relationship between evaporative and non-evaporative heat loss in two resting bird species: passerine and non-passerine

Table 2 Energetic equivivalent of loss body mass at rest, percent heat loss with evaporation, evaporative heat loss, nonevaporative heat loss, and total evaporative water loss, at different ambient temperatures T _A in Budgerigar and European Greenfinch in summer (S) and in winter (W)

Species	T _A = 0°					T _A = T _lc					T _A = T _uc
Species	Q (kJ/g)	H _e (%)	H _e (kJ/day)	H _s (kJ/day)	TEWL (gH₂O/day)	Q (kJ/g)	H _e (%)	H _e (kJ/day)	H _s (kJ/day)	TEWL (gH₂O/day)	Q (kJ/g)	H _e (%)	H _e (kJ/day)	H _s (kJ/day)	TEWL (gH₂O/day)
Melopsittacus undulatus, Summer	30.5	7.1	6.0	74.0	2.4	12.9	18.2	4.7	21.3	1.9	5.1	45.2	11.7	14.3	4.8
Melopsittacus undulatus, Winter	30.0	7.2	5.3	70.9	2.2	12.1	18.7	5.3	23.2	2.2	3.5	63.2	18.0	10.5	7.4
Chloris chloris, Summer	28.2	10.6	8.6	72.8	3.53	12.9	18.8	7.8	33.3	3.18	4.7	50.0	20.5	20.5	8.45
Chloris chloris, Winter	29.0	10.4	8.4	72.0	3.5	15.5	15.8	7.7	40.4	3.2	4.6	57.3	27.6	20.5	11.6

Abbreviations: q energetic equivalent of loss body mass (kJ/g), H _e, %, percentage evaporative heat loss, H _e evaporative heat loss (kJ/day), H _s nonevaporative heat loss (kJ/day), TEWL total evaporative water loss (gH₂O/day), T _A ambient temperatures, T _lc lower critical temperature, T _uc upper critical temperature. Average body mass and number of measured bird as in Table 1
Differences are significant (p < 0.05) between the S and W values in Chloris chloris and are not significant between S and W values in Melopsittacus undulatus

ISSN: 2053-7166