Posted by campossallesfotografia on 19 de August de 2010
Seed dispersion in natural habitats has always been a topic of interest to me. Some of the relationships between fauna and plants is really interesting. For example take the huge Brazil Nut tree, native to the Amazon. The only animal capable of opening up its incredibly hard shells to reach the seeds inside is the small Agouti. Without them, the seeds would never reach the outside world and thus would never germinate. But the story starts with one specific kind of orchid that thrive only in healthy primary rainforests. This orchid produces a scent that a certain species of bee needs to use in order to attract females for reproduction. This bee is the only one that will visit the Brazil Nut flowers and thus pollinize it. So without the orchid there would be no bees, without the bees the tree would never accomplish reproduction and would never produce fruits and seeds. This is the reason why Brazil Nut trees planted in cities never fruit. They are too far from primary forest where there are bees and orchids.
But back to the small Agouti, once the hard shells fall explosively to the ground (you don’t want to stand below a fruiting Brazil Nut tree!), these rodents move in and start munching on the hard, inch thick shells. They reach the large seeds and eat a few but also bury some for later. Thankfully Agoutis don’t seem to have a good memory, because many seeds are buried and forgotten, germinating to maybe one day become the king of the rainforest. Agoutis do the same thing to disperse the seeds of the Acuri palm (the one it is feeding at the photo below). The Acuri is an extremelly important food item to macaws, specially the Hyacinth Macaw.
Another extremelly important seed disperser, this time of smaller seeds, are the toucans and araçaris, such as this striking Chestnut-eared Araçari, a relatively common bird in the Pantanal and adjacent areas. Some of these seeds, such as those from the Açai palm (yes, the energetic drink) can only germinate after the pulp is digested by these birds and later the clean seed is regurgitated somewhere else far from the mother tree. Both photos here were made at the extensive garden and forest trails of the hotel we use in Bonito, during the first part of our Pantanal Tour.