Patterns of natal and breeding dispersal in birds

Abstract

Summary 0[ Dispersal is of critical ecological and evolutionary importance for several issues of population biology\ particularly population synchrony\ colonization and range expansion\ metapopulation and sourceÐsink dynamics\ and population genetic struc! ture\ but it has not previously been possible to compare dispersal patterns across a wide range of species or to study movement outside the con_nes of local study areas[ 1[ Using resampling methods\ we veri_ed that statistically unbiased estimates of average dispersal distance and of intraspeci_c variance in dispersal distance could be extracted from the bird ringing data of the British Trust for Ornithology[ 2[ Using data on 64 terrestrial bird species\ we tested whether natal and breeding dispersal were in~uenced by a species| habitat requirements\ diet\ geographical range\ abundance\ morphology\ social system\ life history or migratory status[ We used allometric techniques to ascertain whether these relationships were independent of body size\ and used the method of phylogenetically independent contrasts to ascertain whether they were independent of phylogeny[ 3[ Both natal and breeding dispersal distances were lower among abundant species and among species with large geographical ranges[ Dispersal distances and life!history variables were correlated independent of phylogeny\ but these relationships did not persist after controlling for body size[ All morphometrical variables "wing length\ tarsus length and bill length# were not signi_cantly correlated with dispersal distances after correcting for body size or phylogenetic relatedness[ 4[ Migrant species disperse further than resident ones\ this relation was independent of body size but not of phylogeny[ A signi_cant positive relation was observed between breeding dispersal distance and long!term population decline among migrants\ but not among residents[ 5[ The species living in wet habitats disperse further than those living in dry habitats\ which could be explained by the greater patchiness of wet habitats in space and:or time[ This relationship was observed only for breeding dispersal\ suggesting that this habitat variable does not impose the same constraint on natal dispersal[ Key!words] body size\ comparative analyses\ dispersal distances\ phylogeny\ ring recoveries[ Journal of Animal Ecology "0887# 56\ 407Ð425

Matrix mediates avian movements in tropical forested landscapes: Inference from experimental translocations

“…Our findings build upon emerging empirical evidence that support long-standing hypotheses that certain species may be more susceptible to extirpation in fragmented systems due to dispersal limitation. In particular, specialists appear more at risk than generalists (Gobeil and Villard, 2002;Haddad, 1999;Lees and Peres, 2009), tropical species appear more at risk than temperate species (Moore et al, 2008), and residents appear more at risk than migrants (Bélisle and St. Clair, 2002;Paradis et al, 1998). This study reveals that whether or not these groups of species ultimately decline in fragmented landscapes may depend in large part on the suitability of the intervening matrix.…”

“…We expected bird movement to be enhanced in peri-urban landscapes compared to bauxite mining landscapes because matrix areas contained greater vegetation cover that could act as stepping stones to aid movement while bauxite matrices lacked this vegetation structure (see Section 2.1). Tropical non-migratory specialists, particularly understory insectivores, are expected to be more dispersal-inhibited than temperate generalist birds (e.g., Harris and Reed, 2002;Paradis et al, 1998;Stratford and Robinson, 2005); thus, we predicted that the American Redstart would have greater return success and quicker return time than the Jamaican Tody across all landscape types.…”

“…Even for well-studied taxa like birds, little is known about movement responses to forest fragmentation, with information on bird dispersal capabilities lacking, particularly in the tropics (Paradis et al, 1998;Walters, 2000). The majority of research on bird movement has been conducted in landscapes of varying amounts of forest cover (e.g., Bélisle et al, 2001) or landscapes solely dominated by an agricultural matrix (e.g., Bayne and Hobson, 2001;Castellon and Sieving, 2006;Gillies and St. Clair, 2008;Hadley and Betts, 2009).…”

Antioxidants in eggs of great tits Parus major from Chernobyl and hatching success

“…This diVerence may be due to radioactive contamination. The Wndings reported here occurred despite extensive dispersal in great tits (Paradis et al 1998), potentially causing Chernobyl populations to be sinks with a net immigration to maintain breeding populations . Several bird species including the great tit with reduced breeding population density due to radioactivity in the most contaminated areas near Chernobyl are more often long-distance dispersers than expected by chance, suggesting that long-distance dispersal may exacerbate the negative eVects of radiation on population density, and that immigration cannot compensate for the negative eVects of radiation on local population density (Møller and Mousseau 2007b).…”

Insights into the migration of the European Roller from ring recoveries

“…Although quantitative data on Roller natal philopatry are limited, we have numerous anecdotal records from populations across Europe of ringed Rollers breeding\1 km from their natal site, and only a handful of records of Rollers dispersing to breed further afield [the record is 334 km from France to Hungary (Vincent-Martin et al 2013)]. As in other species (Paradis et al 1998), breeding dispersal is believed to be substantially lower than natal dispersal, with Rollers often nesting in the same cavity in subsequent years. The potential for natal dispersal to affect our results (by causing us to misidentify true breeding sites) is unavoidable.…”