From: Physiological predictors of reproductive performance in the European Starling (Sturnus vulgaris)
Life-history stage | Outcome variable | Absolute physiological trait value (chick-rearing) | Change in physiological trait value (incubation-chick rearing) |
---|---|---|---|
Workload | Nest visit rate | Cort ↑ (F1,9 = 7841, p < 0.001, n = 43) | Mass ↓ (F1,12.4 = 6.5, p = 0.03, n = 51) |
Brood size at day 6 | – | – | |
Current productivity | BSF1 | dROMs ↓ (z = − 1.95, p = 0.047, n = 53)a | – |
Mean fledging mass, brood 1 | NEFA ↓ (F1,46.1 = 6.6, p = 0.01, n = 50) | Trig ↓ (F 1,45.1 = 5.9, p = 0.02, n = 48) | |
Year 1 total offspring | dROMs ↓ (z = − 2.17, p = 0.03, n = 52)a | Trig ↑ (z = 2.1, p = 0.04, n = 52)a | |
Future fecundity | Probability initiating 2nd brood | – | – |
BSF2 | – | OXY ↑ (z = 2.1, p = 0.04, n = 16)a | |
Mean fledging mass, brood 2 | – | – | |
BSF1 in year 2 | – | – | |
Survival | Local return rate, year 2 | – | – |
Cumulative productivity | No. fledglings over 2 years | – | Trig ↑ (z = 2.5, p = 0.01, n = 12)a |