Deterring Pests Around Hummingbird Feeders
Horrible, horrible idea! It might not kill the hummers right then, but the long term affect on them is horrific. Who would even think its ok. Hummers only live a few years anyway.
Keeping Bees Off Hummingbird Feeders?
Dont use Vaseline or Aquafor. The later has many chemicals in it. People, please seek professional help through a government agency or a local wildlife store. If you make your own nectar then you understand why it is better to make something without chemicals...