Meh...
Let me start of by saying that the music choice and art style where very appropriate for the cartoon and the animation was very good at the end when he eat the bird. That being said, I didn't get it. I didn't get what the walrus was doing or why he was sneaking up on the bird. At first it looked like he was going to try and eat the bird but then he just stairs at it. Then the bear shows up out of nowhere. I don't know if that was an inside reference or what, but what ever it was, I didn't get it. And as I said, the scene where he finally eats the bird was very well done. But as you said, you got lazy with the ending, and it ended rather abruptly. It looks like you have alot of potential, so I do look forward to whatever you make next, but please try and work harder at your humor and don't rush your endings, and you'll come a long way.