by Pajarita » Sun May 11, 2014 11:33 am
No, actually, the finch does NOT need grit. The only birds that need it are birds that eat the seeds or grains whole (like pigeons, doves, chickens, quails, etc). The grit in their gizzard acts like the grinding stone in a mill, crushing the seeds and releasing the nutritious inside so it can then be broken down and digested. Finches are specialized seed eaters while parrots can be both seed eaters and/or nut crackers (depends on the species) but they both have tomia (singular is tomium), a sharp edge that allows them to 'peel' the seed which they then swallow, disposing of the 'shell'. Anybody who has finches, canaries, budgies, tiels, lovies, etc knows that, if you blow on the seed cup, a lot of empty hulls will come up.
Now, there are grits nowadays that are 99% soluble and giving a tiny bit of it is fine (I give my canaries and finches a teeny, tiny treat cup of the soluble type once a month one day and take it out the next morning) but you need to make sure of the solubility because if you buy something like Hartz grit, which is nothing but sand, it's not good for them as it's not digestible and can cause both crop impaction or occlusion lower in the digestive tract.
Parrots do have gizzards. Gizzard is just another name for the ventriculus, which comes after the proventriculus, and it is a muscular 'bag' and the equivalent of our stomach but, by the time the seeds or nuts get there, they are already 'peeled' so, again, grit is not needed.
As to wild stuff you can feed them, you can give the entire dandelion plant (root, stems, leaves and flowers - finches love them and will peck at the roots to get pieces of it but not the parrots); lamb's quarter, purslane and plantain greens, bamboo shoots (only the very tender ones), wild watercress, red clover flowers as well as marigolds and wild violets.