Thank you, it was very sad! They are only a year and a half so she had a short lifeHow sad, I'm sorry for your loss
I don't have Ducks, so am not sure what you can do to help him. Let's tag in @Miss Lydia @shawluvsbirds @Quatie to see if they have any tips for you.
Have you looked him over for injuries/wounds just to make sure he's o.k. (I'm sure you have, but just checking).
but yes, he doesn’t have any wounds. Just sad and lonely they were inseparable 
Thank you for your reply! I thought about getting another duck but he’s pretty mean. I had to separate him and the other duck from the chickens because he’d always try to attack the hens. He’s also pretty mean to our dog lol, he does enjoy the dogs company though, he just chases him around. But since the female died he doesn’t chase him like he used to. I’m torn because I don’t want him to be lonely but I don’t want him to be mean to another duck. I will try and wet down his food in the meantime while I look for a feeding tube. He’s been drinking water still, which I know that’s good but I read they can die from depression and I don’t want him to starve himself to death. Should I still continue to offer him watermelon if he’s eating that, or you would say that’s not enough?I am very sorry for your loss. Be sure to keep him very secure becasue the coyote will come back they remember where free meals are.
Is it possible to get another duck? I am not trying to be callous but he needs companionship they are flock critters and thrive on having a flock even 2 more would be best then you won't have just one left to go through that again and hopefully you never will but this time of year when it is cold normal prey isn't that abundant and predators will look for an easy meal. We have state forums here on BYC we can help. Also there are rescues and farm animal rescues. Check online or call your local animal shelter sometimes they take in poultry or may know someone who has waterfowl.
If he continues not to eat since it's already been 4 days you might want to consider tube feeding him to get him through the worst of his grief and save his life they can stave themselves to death. It sounds intimidating but honestly, it isn't but you'll need the proper equipment to do this. Here is the link for tube feeding https://www.backyardchickens.com/threads/tube-feeding-ducks-updated-5-7-2020.1211994/
you can't just shoot feed into his mouth becasue it can aspirate them so this is the best way to make sure he is getting nourishment.
Also have you tried making his feed into a soupy consistency? sometimes they will drink if not feeling like eating, but I wouldn't wait much longer to get him to eat. also spending a lot of time with him until you can find some ducks for company Another member just lost her duck to illness and they are letting their drake come inside so he isn't alone. Many ways to do this so let us know if you want suggestions.
I am so sorry this happened.
