12 research outputs found
Interspecific variation in the relationship between clutch size, laying date and intensity of urbanization in four species of hole-nesting birds
The increase in size of human populations in urban and agricultural areas has resulted in considerable habitat conversion globally. Such anthropogenic areas have specific environmental characteristics, which influence the physiology, life history, and population dynamics of plants and animals. For example, the date of bud burst is advanced in urban compared to nearby natural areas. In some birds, breeding success is determined by synchrony between timing of breeding and peak food abundance. Pertinently, caterpillars are an important food source for the nestlings of many bird species, and their abundance is influenced by environmental factors such as temperature and date of bud burst. Higher temperatures and advanced date of bud burst in urban areas could advance peak caterpillar abundance and thus affect breeding phenology of birds. In order to test whether laying date advance and clutch sizes decrease with the intensity of urbanization, we analyzed the timing of breeding and clutch size in relation to intensity of urbanization as a measure of human impact in 199 nest box plots across Europe, North Africa, and the Middle East (i.e., the Western Palearctic) for four species of hole-nesters: blue tits (Cyanistes caeruleus), great tits (Parus major), collared flycatchers (Ficedula albicollis), and pied flycatchers (Ficedula hypoleuca). Meanwhile, we estimated the intensity of urbanization as the density of buildings surrounding study plots measured on orthophotographs. For the four study species, the intensity of urbanization was not correlated with laying date. Clutch size in blue and great tits does not seem affected by the intensity of urbanization, while in collared and pied flycatchers it decreased with increasing intensity of urbanization. This is the first large-scale study showing a species-specific major correlation between intensity of urbanization and the ecology of breeding. The underlying mechanisms for the relationships between life history and urbanization remain to be determined. We propose that effects of food abundance or quality, temperature, noise, pollution, or disturbance by humans may on their own or in combination affect laying date and/or clutch size
Interspecific variation in the relationship between clutch size, laying date and intensity of urbanization in four species of hole-nesting birds
The increase in size of human populations in urban and agricultural areas has
resulted in considerable habitat conversion globally. Such anthropogenic areas
have specific environmental characteristics, which influence the physiology, life
history, and population dynamics of plants and animals. For example, the date
of bud burst is advanced in urban compared to nearby natural areas. In some
birds, breeding success is determined by synchrony between timing of breeding
and peak food abundance. Pertinently, caterpillars are an important food source
for the nestlings of many bird species, and their abundance is influenced by
environmental factors such as temperature and date of bud burst. Higher temperatures
and advanced date of bud burst in urban areas could advance peak
caterpillar abundance and thus affect breeding phenology of birds. In order to
test whether laying date advance and clutch sizes decrease with the intensity of
urbanization, we analyzed the timing of breeding and clutch size in relation to
intensity of urbanization as a measure of human impact in 199 nest box plots
across Europe, North Africa, and the Middle East (i.e., the Western Palearctic)
for four species of hole-nesters: blue tits (Cyanistes caeruleus), great tits (Parus
major), collared flycatchers (Ficedula albicollis), and pied flycatchers (Ficedula
hypoleuca). Meanwhile, we estimated the intensity of urbanization as the density
of buildings surrounding study plots measured on orthophotographs. For the
four study species, the intensity of urbanization was not correlated with laying
date. Clutch size in blue and great tits does not seem affected by the intensity
of urbanization, while in collared and pied flycatchers it decreased with increasing
intensity of urbanization. This is the first large-scale study showing a species-
specific major correlation between intensity of urbanization and the
ecology of breeding. The underlying mechanisms for the relationships between
life history and urbanization remain to be determined. We propose that effects
of food abundance or quality, temperature, noise, pollution, or disturbance by
humans may on their own or in combination affect laying date and/or clutch
size
Interspecific variation in the relationship between clutch size, laying date and intensity of urbanization in four species of hole-nesting birds
The increase in size of human populations in urban and agricultural areas has
resulted in considerable habitat conversion globally. Such anthropogenic areas
have specific environmental characteristics, which influence the physiology, life
history, and population dynamics of plants and animals. For example, the date
of bud burst is advanced in urban compared to nearby natural areas. In some
birds, breeding success is determined by synchrony between timing of breeding
and peak food abundance. Pertinently, caterpillars are an important food source
for the nestlings of many bird species, and their abundance is influenced by
environmental factors such as temperature and date of bud burst. Higher temperatures
and advanced date of bud burst in urban areas could advance peak
caterpillar abundance and thus affect breeding phenology of birds. In order to
test whether laying date advance and clutch sizes decrease with the intensity of
urbanization, we analyzed the timing of breeding and clutch size in relation to
intensity of urbanization as a measure of human impact in 199 nest box plots
across Europe, North Africa, and the Middle East (i.e., the Western Palearctic)
for four species of hole-nesters: blue tits (Cyanistes caeruleus), great tits (Parus
major), collared flycatchers (Ficedula albicollis), and pied flycatchers (Ficedula
hypoleuca). Meanwhile, we estimated the intensity of urbanization as the density
of buildings surrounding study plots measured on orthophotographs. For the
four study species, the intensity of urbanization was not correlated with laying
date. Clutch size in blue and great tits does not seem affected by the intensity
of urbanization, while in collared and pied flycatchers it decreased with increasing
intensity of urbanization. This is the first large-scale study showing a species-
specific major correlation between intensity of urbanization and the
ecology of breeding. The underlying mechanisms for the relationships between
life history and urbanization remain to be determined. We propose that effects
of food abundance or quality, temperature, noise, pollution, or disturbance by
humans may on their own or in combination affect laying date and/or clutch
size
Interspecific variation in the relationship between clutch size, laying date and intensity of urbanization in four species of hole-nesting birds
The increase in size of human populations in urban and agricultural areas has resulted in considerable habitat conversion globally. Such anthropogenic areas have specific environmental characteristics, which influence the physiology, life history, and population dynamics of plants and animals. For example, the date of bud burst is advanced in urban compared to nearby natural areas. In some birds, breeding success is determined by synchrony between timing of breeding and peak food abundance. Pertinently, caterpillars are an important food source for the nestlings of many bird species, and their abundance is influenced by environmental factors such as temperature and date of bud burst. Higher temperatures and advanced date of bud burst in urban areas could advance peak caterpillar abundance and thus affect breeding phenology of birds. In order to test whether laying date advance and clutch sizes decrease with the intensity of urbanization, we analyzed the timing of breeding and clutch size in relation to intensity of urbanization as a measure of human impact in 199 nest box plots across Europe, North Africa, and the Middle East (i.e., the Western Palearctic) for four species of hole-nesters: blue tits (Cyanistes caeruleus), great tits (Parus major), collared flycatchers (Ficedula albicollis), and pied flycatchers (Ficedula hypoleuca). Meanwhile, we estimated the intensity of urbanization as the density of buildings surrounding study plots measured on orthophotographs. For the four study species, the intensity of urbanization was not correlated with laying date. Clutch size in blue and great tits does not seem affected by the intensity of urbanization, while in collared and pied flycatchers it decreased with increasing intensity of urbanization. This is the first large-scale study showing a species-specific major correlation between intensity of urbanization and the ecology of breeding. The underlying mechanisms for the relationships between life history and urbanization remain to be determined. We propose that effects of food abundance or quality, temperature, noise, pollution, or disturbance by humans may on their own or in combination affect laying date and/or clutch size
Variation in clutch size in relation to nest size in birds
Parent birds should be selected to choose nest sites and to build optimally sized nests, yet our current understanding of clutch size-nest size relationships is limited to small-scale studies performed over short time periods. Here, we quantified the relationship between clutch size and nest size, using an exhaustive
database of 116 slope estimates based on 17,472 nests of 21 species of hole and non-hole-nesting birds. There was a significant, positive relationship between clutch size and the base area of the nest box or the nest, and this relationship did not differ significantly between open nesting and hole-nesting species. The slope of the relationship showed significant intraspecific and interspecific heterogeneity among four species of secondary hole-nesting species, but also among all 116 slope estimates. The estimated relationship between clutch size and nest box base area in study sites with more than a single size of nest box was not significantly different from the relationship using studies with only a single size of nest box. The slope of the relationship between clutch size and nest base area in different species of birds was significantly negatively related to minimum base area, and less so to maximum base area in a given study. These findings are consistent with the hypothesis that bird species have a general reaction norm reflecting the relationship between nest size and clutch size. Further, they
suggest that scientists may influence the clutch size decisions of hole-nesting birds through the provisioning of nest boxes of varying sizes