You may be right; it could be a stupid idea, I don't know. But I said land animal, not every species on Earth. I don't think he had to carry fish or insects for instance, and that cuts out a whole lot of species. It also depends on who you ask even roughly how species there are today
Ok well... If you ignore everything but the mammals and birds, Noah still would have had to collect a good 90,000 animals to put on the ark.
Of course, we have to understand that insects, reptiles etc can't swim, or spend such an amount of time in water, so we should rightfully include them aswell. From the 3000 different species of snake, to the 'god knows' how many different types of spider.
Further to that, we need to understand that many animals have one small problem: They eat other animals. As such, you would need to separate most, if not all, of the animals on the ark. You could not put a lion with a rabbit, or a rhino with a mongoose.
To keep many of these animals separated, you would need solid steel bar cages and some training with how to keep fierce predators in order.
Further to this, Noah would have to travel the entire globe to seek out all the animals. From the Polar Bears of icy regions to the desert lizard of the sahara. A task such as this is an absolute impossibility.
Furthermore, Many animals kill their own kind until they intend to mate. Scorpions are infamous for killing other scorpions around them as they are solitary animals. Again, more space would be required to cater for all this.
Add the food, add the tremendous weight of animal shit, and you've got a serious problem.
The story is ludicrous. The Ziusudra version at least remains within the realm of possibility. A man on a boat, going to market with some animals, when the Euphrates blows its banks. He floats off into the Persian Gulf and so on..
Anyone who considers the Noah story as a factual account of events, needs a good slap back to the world of reality.