Most of our birds have their own idea of what the right food for them is. But unfortunately it is not always the healthiest.
To convert your seed loving bird over to pellets and veggies requires a lot of time and patience. There are several ideas and ways to do this. I am going to try and cover all the ways that I know in this topic.
1st: Notice which perch your bird hangs out on the most (this is typically the highest perch in the cage) Place a food dish beside the perch with the pellets you would like to convert them to. Leave this here. Your bird will then have a decision to make. Go all the way down to where the regular food is or stay right where they are and eat from the pellets. This plays into the engery expenditure vs. energy gained philosophy.
2nd: mix in pelletted feed with your birds regular seed. This way your bird as to at least touch, possibly pick up and shuffle through to get to their beloved seed. Over time they should begin to realize that these pellets are not going to kill them and might actually be tasty. Other thing you can do is use a pellet feed that is high in fat (lipids taste good) so your bird will be enticed to eat something other than a seed. you can always transition to another pellet once your bird is used to eating them. (stay away from high fat pellets if your bird would naturally have a problem processing lipids)
3rd: If your bird is hand tame and likes to hang out with you, pretend to eat the pelleted feed and then see if they would like to try a piece. They may only taste it and then look at you crazy but over time they may give in. Also, you can put the pellets into your birds cage and remove any seed (for a hour or so) then return the seed. This way your bird only has one option (DO NOT DO THIS FOR AN EXTENDED PERIOD!!!)
4th: To get them to eat veggies: notice first the size seed and or pellet your bird likes to eat. Make the veggies as close to that size to start. Remove seed dishes from cage, place the veggies into the cage with some seed mixed in. Again your bird will want the seed and will have to shuffle through the veggies in order to get some. They will start to taste them and associate them as not being bad for them. Only leave the veggies in the cage for ONE HOUR MAX, the veggies can spoil and inadvertantly cause damage to your bird.
5th: you can hang veggies from the top of the cage like toys. For instance, I hang whole unshucked corn from the top of my cage and the birds have fun ripping at the husk and then getting to the fruity middle. I put broccoli, carrots, apples, anything that will fit and not fall off easily on birdy screwers. Make veggies fun, your bird will probably play with them at first but then will start to realize that they taste good.
6th: sometimes birds like their foods at different temperatures. For example your bird might like frozen veggies fresh out of the fridge or warmed (not to hot) veggies fresh off the stove. Play around with it and figure out what your birdy likes best.
7th: Birds also like grains and pasta. So use dried pasta and make toys out of them, they will enjoy cracking the pieces and playing with the toys. Cook the pasta and mix in with the veggies. You can also make great grain dishes for your birds, veggies and cook tabouleh, couscous, rice and other small bite size grains are often a favorite in my house.
When trying new things like mixing seed over veggies or with the pellets make sure to remove the seed only dish. This way they are forced to eat the seeds out of the pellet or veggie dish. But replace their seed dish after an hour or so, this way they will eat and not starve themselves if they are really picky.
Remember have fun and make sure that if you are feeding fruits and veggies to keep upto date on the toxic things not to feed your birds.
Patience is the key and dont give up because they dont' take to it right away. Some birds take just a little longer. If anyone has anything to add to this please feel free, I have only touched on the basics there are sooo many ways to get your bird to realize that a well rounded diet is best.
