1. Why the Bird Drinking Plum Nectar Is Probably a Japanese White-eye, Not a Bush Warbler
In early spring, it is thought that the Japanese white-eye, not the bush warbler, is the bird that visits plum flowers to drink nectar. The Japanese white-eye has a distinctive white ring around its eye and a bright yellow-green back. [4]
In contrast, the main food of the bush warbler is insects and spiders. Dictionaries state that their diet consists primarily of insects and spiders throughout the year. [1] [2]
There is a theory that the famous pairing of "plum and bush warbler" spread because people confused the two birds. However, this is presented as a popular belief or legend, and clear evidence has not been proven. [4] So, how does the bush warbler find its insects and spiders?
2. How the Bush Warbler Hunts Insects by Looking Up at the Underside of Leaves
The bush warbler looks for prey by hopping between low trees and bamboo grass. They search the undersides of branches and leaves. They find insects by looking up from below, then stretch their bodies upward or make small jumps to catch them. [2]
Nature observation materials from Shimane Prefecture also explain that they eat insects and other creatures while moving actively through the bushes. Because they live in bamboo thickets, their appearance is rarely seen. [3]
It is thought that this is why, even though their song can be heard in gardens, it is rare to see them eating. If they catch insects in the bushes this way, what do they do in winter when insects are scarce?
3. What the Bush Warbler Eats in Winter, Including Ripe Persimmons
The *Nihon Daihyakka Zensho* encyclopedia states that their diet is centered on insects and spiders in all four seasons, but in winter, they also eat some plant matter, such as ripe persimmons. The *Encyclopedia Mypedia* also notes that they mainly eat insects, but sometimes eat berries (fruits with high water content). [2]
Some materials summarize that in summer, they eat small insects, larvae, and spiders, while in winter, they also eat plant matter. However, it cannot be said that "tree fruits are the staple food in winter." The materials suggest that insects remain the main food, with plants being a smaller part of the diet. [4]
In Honshu to Kyushu, they move to lowlands and warmer areas in winter. They can be found in parks with bushes and in residential gardens. Outside of the breeding season, they make a ground call that sounds like a tongue click, "chat, chat," while in the bushes. [1] [2] So, what does this bird look like in winter gardens?
4. What Color the Real Bush Warbler Is, Compared with the Vivid Green in Paintings and Sweets
In paintings and sweets, "bush warbler color" is a vivid green. However, the actual bush warbler is brownish-green all over. Its beak is a blackish-brown color. Because of this dull color, it does not stand out in the bushes. [1]
The size is about 16 cm (about 6.3 inches) in total length for males and about 13–14 cm (about 5.1–5.5 inches) for females, with males being slightly larger. Note that figures vary slightly depending on the source. They live alone or in pairs throughout the year and do not form flocks. [2]
The Japanese white-eye, with its bright yellow-green back and white eye-ring, may be closer to the image of "bush warbler color." It is not surprising that a theory of confusion arose because of this. However, that is also just one theory. [4] So, how can you check this bird's diet for yourself?
5. How to Spot a Bush Warbler in Winter Gardens and Parks by Its Small Brown Look and "Chat, Chat" Call
In winter, in parks and gardens with bushes, listen for a small voice that sounds like a tongue click, "chat, chat." This is described as the ground call of the bush warbler. [2]
If you hear the voice, look gently toward the bushes. If a small brown bird is hopping between bamboo grass or low trees and looking up at the undersides of leaves, it might be eating. However, you cannot identify a bush warbler based on behavior alone. Do not enter the bushes or get too close; please watch quietly from a distance. [3]
Just because you cannot see it does not mean you know if it is a bush warbler. Because they live in bamboo thickets, they are hard to find. If you see one, compare its color with the explanations from the Ministry of the Environment and its size with the dictionary data. [1] [2]
In plum season, there is also the joy of comparing the colors and voices of Japanese white-eyes and bush warblers.