Just so I don't get the rep of being a "softie," my comments were for those of us keeping and enjoying fish in our ponds. They are decorations, pets, and quite often, friends of some sort. And that is as it should be.
But when it comes to breeding fish, I have a whole different approach. Breeding fish, and I do mean when the breeding is intentional, comes with a responsiblilty to the breed itself. And to live up to that responsiblilty, culling is absolutely required. Anyone who calls themselves a "breeder" must have and understand the ethics of breeding and be able to cull the fish in order to improve the breed. That culling most certainly can be done humanely.
This is why I usually advise people to stay out of breeding unless they understand what it entails.
Not talking about the chance spawing that will often take place in the backyard ponds. The only warning I give when that happens is to be aware of the danger of trying to "save them all." If your pond cannot support an exponentially growing population, you could easily loose all the fish in the pond.
Most ponds will take care of a chance spawn. Fish in the pond will eat a majority of the eggs, the filter system will "eat" some too. Fry will be eaten by dragonfly larvae and other aquatic insects. Very few will likely survive to grow and become a problem. The numbers that do can often just fit in with the population. If there's more than you can deal with, find them new homes.
Mostly, you can sit back and enjoy watching the process. Just be aware of what an increase in the pond's population can do to the balance. Maintaining that balance is a large part of pondkeeping in the first place.
Mike S.
Spring Hill, FL