Why did they die

The dodo lived in harmony on the island of Mauritius until 1581.  When humans came to the island on that year, they brought along, among many things other animals. They set dogs free so they could scavenge the island and pigs so they could reproduce and be a good source of food for the humans. Unfortunately, not only humans started hunting the dodos, but the dogs , pigs and rats started to kill the birds too when food supply became scarce.  Dodos were last seen in   1681, 100 years after the humans originally came to the island.