If you’re a golden-eyed migratory sea duck, there are a couple of basic requirements that make life worth living. The first is access to a healthy river, lake of seawater ecosystem—they are generalist feeders meaning they rely on being able to dive and munch on variety of crustaceans, molluscs, water plants, insects and fish eggs. The second, in the broody-breeding time of spring, is a cavity in which to nest, such as a hollowed out tree trunk made by woodpeckers.
Humans, with their clever powers of observation, noticed the duck’s enjoyment of small dark nesting spaces and decided to try strike a deal with them, which went something like: ‘we’ll provide a nice nesting box for you, and in return we’ll take the occasional egg to feed our hungry children with’. The ducks agreed, the humans smiled and ever since little wooden boxes have been erected alongside lakes and rivers—and the person who puts the box up is the only person who is allowed to collect the eggs from the nest—the effort required to secure this valuable fresh source of protein after the long winter months is respected by everyone in the community.