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Summary 1.Public information, i.e. local reproductive performance of conspecifics, is expected to be a highly valuable cue for breeding habitat selection. However, the access to this cue may be spatially and temporally constrained. When public information is unavailable, individuals may use other integrative cues, such as the local density of breeders. 2. Departure decisions of collared flycatchers ( Ficedula albicollis ) were shown previously to be related to both public information and breeding density, in a long-term correlative study of a fragmented population. Here, we tested whether flycatchers also use public information (number and condition of fledglings produced locally) and breeding density to make individual settlement decisions in the following year. 3. Immigration rates were computed to measure the degree of attractiveness of patches to new breeders. We investigated the relative influence of public information and breeding density on immigration rates of yearlings and older adults separately. The access to public information for settlement decisions may indeed be more limited for yearlings. 4. Immigration rate in a patch increased with mean fledgling number in the previous year for older adults but not for yearlings. Yearling immigration rate was correlated positively to mean fledgling condition when patch breeding density in the previous year was low, but negatively when density was high. 5. Immigration rates of both yearlings and older adults increased with breeding density in the previous year. Breeding density explained a larger part of the variance in immigration rate than patch reproductive success. 6. The proportion of yearlings among breeders decreased with increasing patch reproductive success and breeding density in the previous year, suggesting that local competition was high in attractive patches. 7. Our results thus suggest that public information is also used for immigration decisions. However, decisions of yearlings are more complex than those of older adults, due to their more limited access to public information and the higher impact of intraspecific competition. Conversely, all individuals seemed to cue on breeding density in a similar way. Density is correlated to patch reproductive success, and may be a more easily accessible cue. We discuss the potential advantages of using conspecific density over conspecific reproductive performance for future immigration decisions.

Summary 1.Many studies investigating fitness correlates of dispersal in vertebrates report dispersers to have lower fitness than philopatric individuals. However, if dispersers are more likely to produce dispersing young or are more likely to disperse again in the next year(s) than philopatric individuals, there is a risk that fitness estimates based on local adult survival and local recruitment will be underestimated for dispersers. 2. We review the available empirical evidence on parent-offspring resemblance and individual lifelong consistency in dispersal behaviour, and relate these studies to recent studies of fitness correlates of dispersal in vertebrates. 3. Of the 12 studies testing directly for parent-offspring resemblance in dispersal propensity, five report a significant resemblance. The average effect size ( r ) of parent-offspring resemblance in dispersal was 0·15 [95% confidence interval (CI) = 0·07-0·22], with no difference between the sexes (average weighted effect size of 0·12 (0·08-0·16) and 0·16 (0·11-0·20) for females and males, respectively). Only three studies report data on within-individual consistency in dispersal propensity, of which two suggest dispersers to be more likely to disperse again. 4. To assess the magnitude of fitness underestimation expected for dispersing individuals depending on the heritability of dispersal distance and study area size, we used a simulation approach. Even when study area size is 10 times the mean dispersal distance, local recruitment per breeding event may be underestimated by 4-10%, generating a potential difference of 4-60% in average lifetime production of recruits between dispersing and philopatric individuals, with larger differences in long-lived species. 5. Estimates of both fitness correlates of dispersal and parent-offspring resemblance or withinindividual consistency in dispersal behaviour have been reported for 11 species. Although some comparisons suggest genuine differences in fitness components between philopatric and dispersing individuals, others, based on adult and juvenile survival, are open to the alternative explanation of biased fitness estimates. 6. We list three potential ways of reducing the risk of making wrong inferences on biased fitness estimates due to such non-random dispersal behaviour between dispersing and philopatric individuals: (a) diagnosing effects of non-random dispersal, (b) reducing the effects of spatially limited study area and (c) performing controlled experiments.Key-words: dispersal behaviour, intrafamily resemblance, heritability and individual consistency, life-history traits, local apparent survival and recruitment rate, temporary or permanent emigration.