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Table 1 Summary of relationships between chick-rearing physiology, workload, current productivity, future fecundity and survival

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

  1. Direction of associations is indicated by arrows: up arrow for positive associations and down arrows for negative ones
  2. a Not significant (p > 0.05) when n = 3 females with BSF = 0 are excluded