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The hierarchical order of garden birds is determined by their size and weight, according to a new study.
In a study at feeders, researchers at the University of Exeter and the British Trust for Ornithology (BTO) found that larger species such as house sparrows and greenfinches
Meanwhile, small birds such as blue tits and coal breasts had to feed quickly and end up with lower quality foods.
The researchers say the findings have "significant implications" for the use of bird feeders as a method of preservation.
"Bird feeding has become increasingly popular in the United Kingdom and around the world in recent decades," said Professor Jon Blount, lead author of the Center for Ecology and Development.
Retention on the Penryn campus of the Exeter University in Cornwall.
"However, its impacts are still poorly understood." Bird feeders create a concentrated food source that can cause more quarrels between individuals of different species, which we expect would lead to the formation of a hierarchy of dominance.
"Our results show that larger and heavier species have better access to food – so if the goal of bird feeders is to benefit all species, we need to explore ways to improve the quality of life." to achieve it.
Researchers observed birds at the feeders at the edge of forests and hedgerows on the Penryn campus.
They discovered that heavier bird species monopolized access to sunflower hearts – a food whose processing time was relatively short.
Lighter species have been left with sunflower seeds with the shell intact – a food that takes longer to open and eat.
Heavier birds also spawn at a slower rate, while smaller ones spike quickly to make the most of their limited time at the feeders.
The first joint author, Dr. Kate Plummer of the BTO, said: "With more and more people feeding birds in their gardens, it is more important than ever that we understand the implications this could have for the birds themselves. same.
"We know that in harsh weather, food produced by homeowners can offer a lifeline, but beyond that, the benefits could be more subtle.Therefore it is worth noting that our discoveries are less than simple eating."
Dominance ranks of each species were measured by recording any interactions between two individuals, resulting in withdrawal from the food source.
In these cases, the bird that remained was classified as the "winner" (the most dominant) and the other was classified as the "loser".
Although the results do not show the ten species in the exact order of weight, there is a strong correlation between weight and dominance.
The two heaviest birds (based on average weight) were ranked the most dominant – house sparrow (27.3 g) and greenfinch (27.7 g) – while the two lighter – blue tit (10, 9 g) and black tit (9.1 g) – – were at the bottom of the list.
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Material provided by University of Exeter. Note: Content can be changed for style and length.
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