The belief that birds are drawn irresistibly to sparkling treasures has captured human imagination for centuries, creating a legendary image of a feathered thief. This long-held idea is rooted in observable behavior, where certain intelligent birds interact with human-made objects in ways that suggest a fascination with the unusual. Understanding which birds are responsible, and why they engage in this collection habit, requires moving past folklore to the study of avian cognition. This behavior is driven by the scientific realities of curiosity, exploration, and problem-solving in the avian world.
Identifying the Main Culprits
The birds most consistently associated with the theft of small, eye-catching objects belong to the Corvid family, a group renowned for its high intelligence. The Eurasian Magpie is the species most frequently implicated in the folklore surrounding the collection of trinkets. This reputation helped cement the bird’s mischievous image in popular culture, notably inspiring the 1817 opera La Gazza Ladra (The Thieving Magpie). Another prominent member of this family, the Jackdaw, shares a similar historical reputation, particularly in European legends. These birds are often found close to human environments, making their interactions with small, discarded items more noticeable. Other corvids, like crows and ravens, are also highly intelligent and exhibit this same exploratory nature.
Separating Myth from Scientific Reality
The widespread belief that these birds are exclusively attracted to “shiny” things like jewelry or coins is largely a misconception that modern scientific study has challenged. The core attraction is not necessarily reflectivity, but rather novelty—an object that is simply out of place within the natural environment. A shiny metal object stands out dramatically against the muted colors of a typical landscape, making it an immediate target for investigation.
A key study from the University of Exeter tested the “thieving magpie” stereotype by presenting magpies with food alongside shiny metal screws and dull painted objects. The results showed that the magpies either ignored the objects or were cautious and neophobic (fearful of new things) when the novel items were present. In 64 trials, the birds only made contact with the shiny objects twice, suggesting that the attraction to glittering items is far less common than folklore suggests.
The Underlying Reasons for Collection
Curiosity and Exploration
The most significant driver behind collecting unusual objects is the high level of intelligence and curiosity found in these birds. Corvids, including magpies and crows, are known for their problem-solving abilities and their tendency toward neophilia, an attraction to new things. When a bird encounters an unfamiliar item, its impulse is to investigate it, often by picking it up and manipulating it with its beak. This exploratory behavior is a form of learning about the environment. The bird is not necessarily collecting the object for a specific purpose, but rather engaging in a temporary interaction to determine if the item is dangerous, edible, or potentially useful.
Caching and Hoarding
Members of the corvid family have a strong instinct for caching, which involves storing food items for later consumption. This natural hoarding behavior can sometimes extend to non-food items, especially during exploratory phases. A bird may pick up a small object and temporarily store it, treating it as it would a cache of food. The objects themselves are rarely integrated into a permanent collection or nest structure. Instead, collecting non-food items is viewed as an overflow of the caching instinct, where an intriguing novelty is stored until the bird loses interest or forgets its location.
Mate Signaling and Nesting
A hypothesized reason for collecting unusual objects relates to courtship and nest construction. In some bird species, the male will present brightly colored or unique items to a potential mate as a display of resourcefulness and fitness. This suggests that an eye-catching item could serve as a signal of the male’s ability to acquire unusual resources. The collected items may also be incorporated into the nest, not for structural integrity, but as a form of decoration or signaling. While anecdotal reports exist of nests containing shiny human debris, this practice is not widespread or a definitive trait of the species.