Hi,
Could anyone shed any light on why house sparrows would tear strips off leaves on plants & shrubs, then just let them fall to the ground? We noticed it on the buddliea first, then cherry tree & gooseberry bush along with other plants.
This doesn't look like when a bird searches for bugs on plants.
Thank you in advance
Would these be sparrows with young chicks? I think, they only eat insects to feed to the chicks and when they do not find enough insects for their chicks, they damage the leaves hoping to encourage a small supply of pest-eating insects back. ''Damage from insect feeding elicits the release of signaling molecules systemically within the plant. These signaling molecules turn on genes for the production of volatile compounds, acids and alcohols which evaporate into the surrounding air to communicate the presence of the pest insect to pest-eating insects. The leaves of some plants protect from pests because as they are chewed, they release a chemical combination of acids and alcohols that attract pest-eating insects. In fact, plant volatiles can be perceived by any insect or plant in the surrounding area that stands to benefit from knowing the status of the plant.'' I have only seen goldfinches do this, and it happened only over a few days and never again, maybe their impostering didn't work.
I have observed the fledgling Sparrows in my garden dot around trying everything out presumably to see if it's edible, they are the first ones to peck at the Pyracantha berries too!