The blue male doesn't look 100% healthy or happy. It might just be the bird but it should have a straighter back and not a curve in the upper back and rump.
Female budgies tend to bite harder than males. this is for self defense purposes when in the nest. It works on most birds but isn't that good for sexing tame birds.
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I’ve been wanting to adopt ducks myself for YEARS. Haven’t yet though because my dogs have insanely high prey drives 🥲. Specifically welsh harlequin ducks. Because apparently ducks lay eggs just as much as chickens, their eggs are bigger and more nutritious, and I’ve heard ducks are easier to care for but much messier. Welsh Harlequin’s are quiet and are bred for optimized egg laying and naturally flightless. So. Perfect!
Ducks only lay eggs in spring during breeding season. If the eggs are taken, they will lay a second clutch assuming conditions are good.
Most egg laying chickens will produce 6 eggs per week during the main part of their life. They don't need a male to do this.
Chickens and ducks will stop laying eggs for several months each year when moulting.
Duck eggs have a slightly higher fat and protein content than chicken eggs. However, if the chickens are free range and given a wide variety of foods, the eggs will be more nutritious than the ones bought from shops that are produced by battery cage birds.
Dogs can be trained not to attack certain animals/ birds. My dogs knew they weren't allowed to eat the canaries and would sit by the cage watching them when I cleaned the bottom part of the cage. But at the park and in the backyard, anything that moved was fair game.