Welp, it happened.

Today I went to check on the chickens and found my broody silkie dead. I always heard broodies can die on the nest, but never saw it before. Its sad, but I never thought it could actually happen. It was either heat stress or dehydration, i'm thinking both.
Now I have up fresh water and misters and shade.
Is there anything else I can make for them so they dont die from the heat or dehydration? thx

I'm so sorry about your Silkie. I know you're absolutely devastated by this tragedy. You've identified two possible causes of her death, but there is a third one, and it's more common that people think. And the clue this may be cause of your Silkie's death is the very fact of her dying in the nest. It's called sudden death syndrome.

Sudden death syndrome is caused by calcium deficiency. These deficiencies come about suddenly and may not be noticed until it's too late. Most of us are aware of a calcium deficiency when we pull a very thin shell egg from the nest box or we find a shell-less egg splat on the poop board in the morning. When this happens, we have forewarning that the hen has low calcium reserves and we can then treat her for this with a concentrated calcium supplement.

But if we do not get this warning via an egg with a poor shell, then such a hen may go to lay an egg, and when the egg hits the shell gland to get the shell laid over the membrane, there suddenly is no calcium in the shell gland. So, the hen's body draws heavily on the calcium in her blood, trying to find enough to make a shell.

The problem is that the calcium in the blood is already spoken for, required by the heart to keep beating. The tragic consequence is no calcium left to keep the hen's heart beating and she has a heart attack and dies. This is almost always the cause of death when we find a hen dead on her nest.

To prevent this tragedy, it's important to pay attention to the shell quality of each of our hens' eggs. It's a very simple matter to treat. I use this form of calcium since it's the easiest to digest and absorb. One tablet each day directly in the beak, whole, not diluted. Do this until egg shell quality is good again. You will prevent not only the tragedy of sudden death syndrome, but egg binding which can be life threatening.

How ventilated is your coop?

I see you’re in Arizona. My brother lives in Phoenix. And this time of year, it’s easy for birds to get overheated. Broodies especially. He put a kiddie pool in his run. But he dug out a hole so the rim was the only things above ground. Then he put a low roof over it so sun never hit it directly. It kept the water MUCH cooler and his chickens would hang out underneath that roof in particular. It made a tiny micro climate for them that was cooler.

My Bagurks said:

How ventilated is your coop?

I see you’re in Arizona. My brother lives in Phoenix. And this time of year, it’s easy for birds to get overheated. Broodies especially. He put a kiddie pool in his run. But he dug out a hole so the rim was the only things above ground. Then he put a low roof over it so sun never hit it directly. It kept the water MUCH cooler and his chickens would hang out underneath that roof in particular. It made a tiny micro climate for them that was cooler.

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its very ventilated, I think the hen died in the night and couldn't find any water because it was dark

Maybe, but I have never had any of my birds lay shell less eggs. This whole week is a heat wave, She died 2 days ago and before that day so 3 days ago it reached 114F. I hoped that she would be smart and drink some water and get out, but she never did. She died 2 days ago, when I found her in the early morning rigor mortis was in full effect so she died sometime through out the night with the others on the roost by the nest she was on. I think the heat combined with her extreme dehydration "sealed the deal" for her fate.

My Bagurks said:

How ventilated is your coop?

I see you’re in Arizona. My brother lives in Phoenix. And this time of year, it’s easy for birds to get overheated. Broodies especially. He put a kiddie pool in his run. But he dug out a hole so the rim was the only things above ground. Then he put a low roof over it so sun never hit it directly. It kept the water MUCH cooler and his chickens would hang out underneath that roof in particular. It made a tiny micro climate for them that was cooler.

Click to expand...

Its heavily ventilated, its never humid, always dry

This has just happened to me today - we're having a heatwave in the UK and my broody has been sat on a clutch for a week now. I could see she wasn't drinking and eating as much as she should even though i had put food and water right in front of her and was lifting her off the nest every day. It's really upsetting and as this was only the second time i've tried to hatch eggs under a broody hen I'm not sure if i can do it again