How did our goldfish die?

[Dave 54]

Some Herons are nocturnal, called night herons.

I sure can't tell from the pics but if the wound looks like meat it could be an injury. If the wounds look while and nasty, like an infection, I'd assume it was caused by bacteria, virus or fungus. It is possible an injured fish could live and the wound get infected so impossible to tell. Playing the odds the overwhelming choice would be infection, not animal attack. I think most people like thinking it's an animal rather than poor water quality.

Infection is generally a bigger risk in spring. Fish immune system is much lower at lower temps and as water temp increases there is a window where bacteria booms while fish immune systems are weak.

I have to agree with waterbug on this it may well be a heron but if anymore goldfish start to exibit these injuries and no preditor has been seen at all then it is most probably bacterial.
You can help prevent infections by cleaning your pond and filters late fall , clean again in Late spring and again in the summer , dont forget plenty of water changes and to test your water perameters eery week without fail this way you can keep on top of things .

Dave

 

[j.w]

Thank you, everyone. I saw the rest of the fish. I sprinkled food on the pond and then went inside to watch from the window. They all looked okay as far as I could tell.

I ended up putting a stiff, plastic mesh cover over the pond. It's ugly, but I'd rather keep the fish safe for now.

The fish we lost was the whole reason for building a pond in the first place. My kids won her at a fair two years ago. So sad/mad.

If you decide to change your net you might choose to raise it up and use wider weave thinner net. It's still not beautiful but it sure puts my mind at ease as far as the heron goes and I can see through it and lift up the hanging edges to get under it easy to maintain. I don't let it hang all the way to the ground as an animal (my cat did and fortunately I was out there when she did ) can get tangled in it. I have a short wire fence around the bottom about 18" tall to connect the net to w/ hooks that are easy to remove.

https://www.gardenpondforum.com/threads/heron-netting-101.13205/

 

[addy1]

I use the same netting as jw, it works great, critters don't get stuck, but it sure keeps the heron out of the pond.

 

[Shan]

Thank you for the fencing ideas!