In Manu, as in many other area of the western Amazon, Macaws will come daily to feed on clay from a clay lick or ‘collpa’. This is a good opportunity to see large numbers of the birds, which can be quite spectacular, as well as the endangered blue-headed macaw.
There is quite a lot of speculation as to why macaws do this. Some scientists believe that they feed at the collpas because the clay has high levels of sodium, an important dietary requirement that is rare so far from the sea. Others think that the clay neutralises toxins that the macaws ingest with some of their foods.
They are also known to feed clay to their young during breeding season and their use of collpas peaks during this time.
Researchers often use this phenomenon to monitor trends in bird numbers as they can see day to day how many turn up to ingest the clay. In the Manu area some are currently monitoring the blue-headed macaw, an endangered species.