The city pigeon, or Rock Dove (Columba livia), is one of the most common birds worldwide, making encounters with its nests and eggs frequent in urban environments. Identifying these eggs requires considering their physical characteristics, the nesting environment, and differences from other common urban birds.
Physical Identification: Size, Shape, and Color
Pigeon eggs are characterized by their uniform, unblemished white or creamy-white color. This pure white appearance is a significant identifying feature, as the eggs lack the spots, blotches, or speckling common on the shells of many other bird species. The shape of the egg is a classic oval, though it can appear slightly more rounded than those of other birds. Size is consistent, typically measuring approximately 39 millimeters (1.5 inches) in length and 29 millimeters (1.1 inches) in width. The shell surface is generally smooth and non-glossy.
Where to Find Them: Nesting Habits and Environment
The location and structure of the nest provide context that is often more telling than the egg itself. Rock Doves are descendants of cliff-dwelling birds, and in cities, they seek sheltered, elevated locations that mimic rocky ledges and crevices. Urban nesting sites frequently include window ledges, under bridges, building eaves, ventilation shafts, or abandoned infrastructure. The nest itself is typically a flimsy, rudimentary structure—a chaotic platform of a few scattered twigs, straw, or debris. Unlike the carefully woven cups of songbirds, the nest is often so sparse the eggs are visible through the construction. Pigeons almost exclusively lay only two eggs per brood, though a single egg is occasionally found.
Key Differences: Pigeon Eggs Versus Other Urban Bird Eggs
Differentiating a pigeon egg from those of other urban species relies on comparing color, size, and clutch structure. The uniform white color immediately distinguishes it from the speckled appearance of many smaller songbirds.
House Sparrow
The House Sparrow (Passer domesticus), a common urban resident, lays eggs that are significantly smaller, measuring around 15 millimeters (0.6 inches) in length. House Sparrow eggs are typically white, gray, or greenish-tinted but are always covered with brown specks or blotches. Sparrow clutches are also much larger, regularly containing three to seven eggs, contrasting with the pigeon’s standard two-egg clutch.
Mourning Dove
The Mourning Dove (Zenaida macroura) is a closer relative and can cause confusion, as it also lays a white or pale creamy-white egg. However, the Mourning Dove egg is generally slightly smaller. Their nests, while also flimsy, are more likely to be found in trees or shrubs in suburban and rural settings. The city pigeon is also a noticeably larger, stockier bird, reflected in the slightly larger size of its egg.