Effects of interspecific coexistence on laying date and clutch size in two closely related species of hole-nesting birds

TY - JOUR

T1 - Effects of interspecific coexistence on laying date and clutch size in two closely related species of hole-nesting birds

AU - Møller, Anders Pape

AU - Balbontín, Javier

AU - Dhondt, André A

AU - Remeš, Vladimir

AU - Adriaensen, Frank

AU - Biard, Clotilde

AU - Camprodon, Jordi

AU - Cichoń, Mariusz

AU - Doligez, Blandine

AU - Dubiec, Anna

AU - Eens, Marcel

AU - Eeva, Tapio

AU - Goodenough, Anne E

AU - Gosler, Andrew G

AU - Gustafsson, Lars

AU - Heeb, Philipp

AU - Hinsley, Shelley A

AU - Jacob, Staffan

AU - Juškaitis, Rimvydas

AU - Laaksonen, Toni

AU - Leclercq, Bernard

AU - Massa, Bruno

AU - Mazgajski, Tomasz D

AU - Nager, Ruedi G

AU - Nilsson, Jan-Åke

AU - Nilsson, Sven G

AU - Norte, Ana C

AU - Pinxten, Rianne

AU - Robles, Hugo

AU - Solonen, Tapio

AU - Sorace, Alberto

AU - van Noordwijk, Arie J

AU - Lambrechts, Marcel M

N1 - 6635, AnE; Data Archiving: data archived at Dryad

PY - 2018/11

Y1 - 2018/11

N2 - Coexistence between great tits Parus major and blue tits Cyanistes caeruleus, but also other hole-nesting taxa, constitutes a classic example of species co-occurrence resulting in potential interference and exploitation competition for food and for breeding and roosting sites. However, the spatial and temporal variations in coexistence and its consequences for competition remain poorly understood. We used an extensive database on reproduction in nest boxes by great and blue tits based on 87 study plots across Europe and Northern Africa during 1957-2012 for a total of 19,075 great tit and 16,729 blue tit clutches to assess correlative evidence for a relationship between laying date and clutch size, respectively, and density consistent with effects of intraspecific and interspecific competition. In an initial set of analyses, we statistically controlled for a suite of site-specific variables. We found evidence for an effect of intraspecific competition on blue tit laying date (later laying at higher density) and clutch size (smaller clutch size at higher density), but no evidence of significant effects of intraspecific competition in great tits, nor effects of interspecific competition for either species. To further control for site-specific variation caused by a range of potentially confounding variables, we compared means and variances in laying date and clutch size of great and blue tits among three categories of difference in density between the two species. We exploited the fact that means and variances are generally positively correlated. If interspecific competition occurs, we predicted a reduction in mean and an increase in variance in clutch size in great tit and blue tit when density of heterospecifics is higher than the density of conspecifics, and for intraspecific competition, this reduction would occur when density of conspecifics is higher than the density of heterospecifics. Such comparisons of temporal patterns of means and variances revealed evidence, for both species, consistent with intraspecific competition and to a smaller extent with interspecific competition. These findings suggest that competition associated with reproductive behaviour between blue and great tits is widespread, but also varies across large spatial and temporal scales.

AB - Coexistence between great tits Parus major and blue tits Cyanistes caeruleus, but also other hole-nesting taxa, constitutes a classic example of species co-occurrence resulting in potential interference and exploitation competition for food and for breeding and roosting sites. However, the spatial and temporal variations in coexistence and its consequences for competition remain poorly understood. We used an extensive database on reproduction in nest boxes by great and blue tits based on 87 study plots across Europe and Northern Africa during 1957-2012 for a total of 19,075 great tit and 16,729 blue tit clutches to assess correlative evidence for a relationship between laying date and clutch size, respectively, and density consistent with effects of intraspecific and interspecific competition. In an initial set of analyses, we statistically controlled for a suite of site-specific variables. We found evidence for an effect of intraspecific competition on blue tit laying date (later laying at higher density) and clutch size (smaller clutch size at higher density), but no evidence of significant effects of intraspecific competition in great tits, nor effects of interspecific competition for either species. To further control for site-specific variation caused by a range of potentially confounding variables, we compared means and variances in laying date and clutch size of great and blue tits among three categories of difference in density between the two species. We exploited the fact that means and variances are generally positively correlated. If interspecific competition occurs, we predicted a reduction in mean and an increase in variance in clutch size in great tit and blue tit when density of heterospecifics is higher than the density of conspecifics, and for intraspecific competition, this reduction would occur when density of conspecifics is higher than the density of heterospecifics. Such comparisons of temporal patterns of means and variances revealed evidence, for both species, consistent with intraspecific competition and to a smaller extent with interspecific competition. These findings suggest that competition associated with reproductive behaviour between blue and great tits is widespread, but also varies across large spatial and temporal scales.

KW - international

UR - https://doi.org/10.5061/dryad.p763611

U2 - 10.1111/1365-2656.12896

DO - 10.1111/1365-2656.12896

M3 - Article

C2 - 30101503

SN - 0021-8790

VL - 87

SP - 1738

EP - 1748

JO - Journal of Animal Ecology

JF - Journal of Animal Ecology

IS - 6

ER -