1 Reindeer, 2 Reindeers?

"Foot" is a good example of an  irregular plural noun: one foot,  

2 feet. What about reindeer? One reindeer  versus a herd of reindeer. No change. That's  

similar to "moose": one moose,  a few moose. Again, no change.

It would be bad to find one mouse  in your house . It would be worse  

to find nest of mice. Let's  say I went fishing yesterday,  

and I caught one fish. You perhaps caught two  fish. If you went snorkeling or scuba diving,  

you might actually see a school of fish. No  change. But a scientist who studies different  

species of fishes would use that -es ending  (fishes) for different kinds different species.

How about goose? One goose is flying in the air.  You might actually see a whole flock of geese.

We can also use flock when we talk about sheep:  one sheep, a flock of sheep. I've heard "flock of  

sheep" and "herd of sheep." I think technically  there is a difference. "Flock of sheep" means  

they've been herded together. "A herd of  sheep" means they're just out there roaming.

And finally, ox: one ox, a herd of oxen. It's  

not a very common irregular plural  noun, but it's still good to know.

Can you think of any other irregular  plural nouns that refer to animals?