Backyard poultry keepers often wonder if snakes near their coops pose a threat to their eggs. Understanding local snake species provides clarity and helps in adopting appropriate coexistence measures.
Understanding Black Snakes and Their Diet
Certain “black snakes,” particularly rat snakes, do consume chicken eggs. The most common varieties in North America are the Eastern Rat Snake (Pantherophis alleghaniensis) and the Western Rat Snake (Pantherophis obsoletus). These non-venomous constrictors are often called “chicken snakes” due to their tendency to frequent chicken coops in search of food.
While eggs are an opportunistic food source, the primary diet of rat snakes consists of rodents such as mice, rats, and chipmunks. They also prey on small birds, lizards, and frogs. Their ability to climb trees and structures, including the rafters of buildings, allows them to access bird nests and, consequently, chicken coops.
How Snakes Consume Eggs
Rat snakes possess a unique method for consuming eggs. They swallow eggs whole, without crushing them externally. This is facilitated by their flexible jaws, which can disarticulate and spread widely.
After swallowing, the egg moves into the snake’s throat, where specialized vertebral protrusions, sometimes described as bony spines, are used to break the shell internally. The snake then contracts its muscles to squeeze the liquid contents from the broken shell. The crushed, flattened shell is typically regurgitated.
Coexisting with Black Snakes
Rat snakes play an important role in natural ecosystems, primarily by controlling rodent populations. This can be beneficial for chicken keepers, as a reduction in rodents also reduces a primary attractant for snakes to the coop. These snakes are generally shy and will attempt to avoid confrontation.
To deter snakes from chicken coops without causing harm, securing the coop is a primary step. This involves inspecting for and sealing any gaps or openings larger than 1/4 inch, as snakes can enter surprisingly small spaces. Using hardware cloth with a small mesh size (1/4 inch or less) instead of chicken wire is recommended for coop construction and sealing, as it creates a more effective barrier. Additionally, burying hardware cloth 12-18 inches deep around the perimeter of the coop can prevent burrowing.
Maintaining a tidy area around the coop also helps, as snakes seek out hiding spots like tall grass, debris piles, and wood stacks. Removing spilled chicken feed and ensuring feed is stored in rodent-proof containers can reduce the presence of rodents, thereby making the coop less appealing to snakes. Regularly collecting eggs minimizes the available food source for opportunistic snakes.