Car traffic along hedgerows affects breeding success of Great Tits Parus major

Figures & data

Figure 1. The average number of eggs laid per nest and the average number of fledglings per nest from nests in hedgerows alongside roads with three different disturbance grades. Zero values, i.e. complete brood failures, are included in the fledgling average. 95% confidence limits are shown.

Figure 2. Percentage of dead broods and fledging success from nests in hedgerows alongside roads with three different disturbance grades. 95% confidence limits are shown for fledging success.

Table 1. Great Tit nest breeding variables and number of nests that reached clutch, brood and fledging stages, classified according to hedgerow disturbance grade.

	Undisturbed	Slow traffic	Fast traffic
Laying date of first egg	26 April + 1.79 days	29 April ± 3.49 days	25 April + 1.95 days
Weight (15 days old)	15.78 ± 0.40 g	14.97± 0.65 g	15.43 ± 0.56 g
Fledgling age	17.97 ± 0.27 days	17.85 ± 0.35 days	18.0 ± 0.0 days
Number of clutches	35	30	28
Number of broods	34	29	28
Number of nests with fledglings	31	26	14