TY - JOUR
T1 - Density-dependent recruitment rates in great tits: the importance of being heavier
AU - Both, C.
AU - Visser, M.E.
AU - Verboven, N.
N1 - Reporting year: 1999
Metis note: 2494; CTE; PVD ; AnE; file:///L:\EndnoteDatabases\NIOOPUB\pdfs\Pdfs1999\Both_ea_2494.pdf
PY - 1999
Y1 - 1999
N2 - In birds, individuals with a higher mass at fledging have a higher probability of recruiting into the breeding population. This can be because mass is an indicator of general condition and thereby of the ability to survive adverse circumstances, and/or because fledging mass is positively related to competitive strength in interactions with other fledglings. This latter explanation leads to two testable predictions: (i) there is stronger selection for fledging mass when there is more severe competition (i.e. at higher densities); and (ii) that besides absolute hedging mass, relative mass of fledglings within a cohort is important. We test these two predictions in two great tit (Parus major) populations. The first prediction was met for one of the populations, showing that competition affects the importance of mass-dependent recruitment. The second prediction, that fledglings recruit relatively well if they are heavy compared to the other fledglings, is met for both populations. The consequence of the importance of relative rather than absolute fledging mass is that the fitness consequences of reproductive decisions affecting fledging mass, such as clutch size, depend on the decisions of other individuals in the population. [KEYWORDS: Parus major; density dependence; selection; body mass; fledging mass; recruitment Parus-major; clutch size; juvenile survival; nestling weight; song sparrows; population; dominance; selection]
AB - In birds, individuals with a higher mass at fledging have a higher probability of recruiting into the breeding population. This can be because mass is an indicator of general condition and thereby of the ability to survive adverse circumstances, and/or because fledging mass is positively related to competitive strength in interactions with other fledglings. This latter explanation leads to two testable predictions: (i) there is stronger selection for fledging mass when there is more severe competition (i.e. at higher densities); and (ii) that besides absolute hedging mass, relative mass of fledglings within a cohort is important. We test these two predictions in two great tit (Parus major) populations. The first prediction was met for one of the populations, showing that competition affects the importance of mass-dependent recruitment. The second prediction, that fledglings recruit relatively well if they are heavy compared to the other fledglings, is met for both populations. The consequence of the importance of relative rather than absolute fledging mass is that the fitness consequences of reproductive decisions affecting fledging mass, such as clutch size, depend on the decisions of other individuals in the population. [KEYWORDS: Parus major; density dependence; selection; body mass; fledging mass; recruitment Parus-major; clutch size; juvenile survival; nestling weight; song sparrows; population; dominance; selection]
U2 - 10.1098/rspb.1999.0660
DO - 10.1098/rspb.1999.0660
M3 - Article
SN - 0962-8452
VL - 266
SP - 465
EP - 469
JO - Proceedings of the Royal Society B-Biological Sciences
JF - Proceedings of the Royal Society B-Biological Sciences
IS - 1418
ER -