Are penquins of Antarctica going to become extinct soon as a result of this?

Not necessarily. Penguins have always had predators to deal with when swimming for food. Sea lions are always waiting to pick them off, I think it might be more dangerous to the sea lions. If anything, it might reduce the population a little, but is unlikely to make them go extinct. If a large land predator such as a bear was to migrate there, that would be a different story