He will stop, ... and then you should get a new 1 also.

Even if they were not a "true" pair, (one male and one female), you have to remember that birds are flock animals, so they want to be around other members of their flock. The remaining bird is definitely lonely, but this could be an ideal time for the two of you to bond, rather than jumping in to get him another "female". (There are so many colors of cockatiels out there today that it's almost impossible to tell sex just by visual cues, unless they've actually been a proven--raised babies from their own eggs--breeding pair.) "His" chirping will stop much faster if you spend more time with him and allow the bonding process to begin, but if they were a breeding pair, then he might not be happy without another hen. HOWEVER, be very careful about just buying another bird and putting it in the cage with him--even if he's lonely, it doesn't guarantee that they will get along. Females can be aggressive, and you wouldn't want them to hurt each other when you're just trying to help ease the loneliness of losing his mate. Some new toys will also help if you choose not to spend the extra time with him--cockatiels usually love rope and wood toys!--but avoid toys with mirrors, as they might make him think there is another bird in the cage with him again and increase his frustration level. Good Luck! Please feel free to email me if I can be of any further assistance.

I'd say to get him another mate because it wouldn't be right to leave the poor fellow to be all by himself.

the best way to heal a broken heart is time and companionship from friends. I do believe your little guy is going through separation anxiety. HE is having a hard time not having his sweet heart around anymore. just like a human losing a loved one, it takes time to heal. I would wait a month or two to see if he gets back to normal. In this couple months spend lots of time with him to see if maybe he will heal from his loss. if he persists the screeching and chirping, i would get him a new friend so he can move on and not be so lonely. i do believe getting him a new friend to spend his time with will help him feel back to normal and not so sad and lonely after losing his "wife". (only if you would like to take on another pet that is).

How sad. I have a Parrot and two Parakette's, the parakett's are in love. Sounds like your cockatiel is missing his. Please consider getting him a new love, it really will make his life worth living again. In the meantime, a little mirror to look into with help with the lonliness. Toys in his cage help too, until you bring home the new bird. :]

Either you need to get another one, or spend a lot of time with your remaining bird. They are very social. If you talk to him a lot, he may even learn to talk back. (My aunt's used to call the cat "Here kitty kitty kitty") Cause he heard my aunt call the cat so much. Once he gets comfortable with that and is reassured that you also will not leave him alone, he'll be a happier bird. Even if you get another bird to keep him company he may take a bit to get used to the new bird.

Not to sound insulting towards your bird's intelligence... still, if you put a doll type cockatiel in his cage, would that help?

Cockatiels get lonely. You should either give me much more attention and toys and see if that helps, or find a new hen. But remember that he may not accept her at first, or even at all if he is too broken hearted so have a separate cage for her ready. At least if they can't be in the same cage, they can be near each other.