Why do my parakeets chew perches and only eat from high food dishes?

It's definitely normal and is more of a nesting/boredom behavior rather than an indication of a vitamin or mineral deficiency. You can get them to chew on other toys or other objects if you want to minimize the damage to the perches and ladders. Below is a link to some good ideas for keeping them busy. http://www.parrotenrichment.com/ I hope that helps and all is well with the Budgies.

Destroying wooden toys and ladders is actually natural behavior in birds and is good enrichment. Some things you can do is offer a variety of other toys and things that they can destroy. Use newspaper or cardboard rolls to wrap and hold treats to give them something to destroy and forage at the same time. You can consider getting slightly thicker woofer toys that may last longer or combining some plastic perches and ladders with wood. A variety of shape sizes and textures is healthier than one size and style only. Concrete type perches help to file thier nails. Wood such as Manzanita is extremely hard and much more durable than the plain wood perches. Below are some toy ideas. There are also resources available on the web to see what tree branches you may have in your yard that are safe for perches. https://lafeber.com/pet-birds/top-toys-for-parakeets/ https://lafeber.com/pet-birds/bird-owners-can-find-new-uses-for-these-recyclables/

Birds can sometimes considering being higher up than another object as "being above it" in a hierarchical sense. Interacting with Kiwi while keeping him on a lower perch, or encouraging him to step down lower with a treat prior to interacting may help reduce any aggression or biting behaviors while perched higher.

You can secure the food dish to the cage so she can't tip it over. Shouldn't be hard to do. Sometimes they will sit at the bottom of the cage and that would be normal. If it becomes excessive she could be sick, in which case, she needs to see a vet. I suggest you put more toys and things in the cage for her to do and play with. She sounds bored. Also, an all seed diet is not recommended for any bird. I suggest you try to switch her over to Lafeber's Nutriberries or AviCakes. There is a lot of good information on their website. ( https://lafeber.com/pet-birds/species/lovebird/ )

Thanks for reaching out. Are these birds becoming more mature, therefore hierachy changing, or competition over food, perches, territory? The daily diet should consist of some seed but also fresh vegetables (all), a protein source such as cooked beans/tofu, therefore treats can be fruit (dried, fresh). Good luck.

It may be a dominance behavior. Consider a larger cage for them with additional food and water bowls to prevent resource protection. A concrete perch or sandpaper perch wraps may help keep nails trim. You can also clip them yourself or have them clipped if you have never done it before. If the behavior persists or worsens, you may need to cage them separately to prevent injury.

I see that you posted this question a while back, and I answered it there, so I'll repost my answer here for you to be sure you get it. Patience and time! Until he's 100% on his training, be sure to always reward with a treat. However, if he's perfect at it with a treat every time, you can start to wean off them. You can try luring him with the treat to get him to perch, and then start only giving him treats intermittently. If he doesn't know when he's getting a treat and when he isn't, he may be more inclined to keep trying in the hopes he gets one sometimes. You can also use a favorite toy to play with, a gentle pet in a place he enjoys, or some of his regular food instead as a "treat" while you're phasing out the real ones.