The Wood Pigeon, Columba palumbus, is the largest and most widespread pigeon species across Europe and western Asia, thriving in diverse habitats from rural woodlands to urban parks. This highly adaptable bird has successfully expanded its range and population by developing a flexible feeding strategy. Its diet is primarily vegetarian, shifting significantly throughout the year to capitalize on changing food availability. Understanding the Wood Pigeon’s diet involves examining its foundational food sources, how these sources fluctuate with the seasons, and the unique biological process it uses to nourish its young.
Primary Components of the Wood Pigeon Diet
The foundational diet of the Wood Pigeon is largely herbivorous, centered on a wide array of plant matter gathered primarily from the ground. As a ground-feeder, the bird consumes numerous types of seeds from wild grasses and weeds, establishing a baseline intake of carbohydrates and fats. Seeds from plants like wild vetch and catchweed are regularly consumed, providing a consistent energy supply.
Green matter forms a substantial and constant part of their diet, distinguishing them from strictly granivorous birds. They frequently forage on the leafy parts of plants, including clover, young shoots, and the fleshy leaves of various cruciferous vegetables. This consumption of vegetative material provides moisture and micronutrients that complement the energy-rich seeds. Additionally, in late winter and early spring, they consume the buds and shoots of trees and bushes.
Their powerful gizzard allows them to process hard items, enabling them to crush and digest large seeds and grains. While their diet is dominated by vegetation, they are not strictly vegetarian and will occasionally consume small invertebrates. Earthworms, slugs, and insects are sometimes taken, though these animal sources constitute a very minor and opportunistic part of their overall food intake.
Seasonal Variation and Opportunistic Feeding
The Wood Pigeon’s diet exhibits significant plasticity, adapting to the seasonal abundance of different food resources. This opportunistic feeding behavior allows them to maintain a high caloric intake throughout the year by switching between staples. The transition between seasons is often marked by a shift from tree-based foods to ground-based crops.
During the summer and early autumn, their diet is dominated by cereal grains harvested from agricultural fields. They consume significant quantities of wheat, barley, maize, and oats, frequently foraging on stubble left after harvesting. In contrast, winter and spring see a greater reliance on the fruits and seeds of trees, such as high-fat acorns from the Quercus genus.
Seasonal fluctuation also includes a reliance on soft fruits and berries when they ripen. They will gorge on forest and hedgerow fruits, like those from the mastic tree, and also target cultivated fruits such as cherries and plums. Furthermore, the cultivation of high-energy crops, particularly oilseed rape and brassicas, offers a rich food source during the colder months.
Specialized Dietary Needs for Young
The feeding of Wood Pigeon hatchlings, known as squabs, involves a unique biological process distinct from how the adults forage. Instead of feeding their young on regurgitated seeds, the parents produce a substance called “crop milk.” This milk is a highly nutritious, semi-solid secretion produced by the sloughing of fluid-filled cells from the lining of the adult birds’ crop.
Both the male and female parent produce this milk, a process regulated by the hormone prolactin. The composition of crop milk is extremely rich, containing a higher percentage of both fat and protein than cow or human milk, though it contains no carbohydrates. This substance is the sole source of nourishment for the squabs during their first week of life.
The parents begin to introduce small amounts of softened adult food into the crop milk mixture after the first few days. This gradual transition allows the young bird’s digestive system to acclimate to solid food. By the end of the second week, the squabs are fed entirely on regurgitated adult food, ensuring rapid growth and development.