It is also important to note that my analysis assumes that a single visit per tree by the mechanical shaker is enough to remove the majority of mummy nuts.
The tombs were opened, all the valuables removed, and the mummies collected into two large caches.
To highlight this issue properly, I have added the following text to the Discussion: "The fact that birds did not remove all mummy nuts prior to the next almond flowering highlights the important point that ecosystem-service provision in this case does not replace completely the need for human input to achieve acceptable outcomes.
The fact that birds did not remove all mummy nuts prior to the next almond flowering highlights the important point that ecosystem-service provision in this case does not replace completely the need for human input to achieve acceptable outcomes.
Second, the averaged values (across the entire plantation) assume that birds will remove most mummy nuts within a given time frame, negating the need entirely for mechanical or manual removal by growers.
In 1922, looters removed the body of a young female mummy that was buried with associated offerings including a cumbi tunic, a textile bag, one belt, three combs, and a feather adornment made from tropical birds on her head [ 46].
Nevertheless, it is important to recognise the spatial variation that occurred in bird activity and subsequent cost and benefit outcomes, and the fact that birds did not remove all mummy nuts.
I am unaware of any similar guidelines for Australia, possibly because threats associated with mummy-nut retention (e.g. carob moth infestations) are relatively new, but it is important to recognise that bird activity is unlikely to remove all mummy nuts from trees before onset of the next crop.
The replacement cost estimate of mechanical shaking is conservative because I assumed shaking will remove most mummy nuts in a single visit, but this may not be the case; mummy nuts occur because mechanical shaking during harvesting does not dislodge every almond from a tree.
