For the duration of the 2020 baseball season, I hear, the Toronto Blue Jays played their games in the stadium of their farm team, the Buffalo Bisons.

The Buffalo Bisons. I don’t know. That’s a little on the nose for a team name, isn’t it? It would be like if Marmot, Oregon had a team called the Marmot Big Fat Rodents. Also? The plural of bison is bison.
Which makes “bisons” wrong in the exact opposite way people are currently getting plurals wrong. Something has happened to perfectly good plurals. Lately, people have been losing their esses all over the place. It’s a field of “irises,” people, not a field of iris. And it’s “ospreys,” not a family of osprey. And it’s “octopuses.” (Or octopodes.) And, well, it never ends. You can’t just drop the S willy-nilly and think you’ve nailed it.
I do understand that this is English and as such it is destined to be confounding. When you’ve got a big muscular language like ours that has plundered every other language for spare parts and an operating system, nothing is going to make sense.
But it is sort of helpful that a thick swath of our nouns gets pluralized by adding an S. Not all of them, of course. But that S can get you a long way, and you should not be unduly afraid of it.
Some nouns do not get an S because they’re considered “uncountable.” Rice, for instance. You don’t buy a bag of rices. The grains are countable, and get an S, but the rice, not so much.
There are irregular plurals. If you have more than one mouse, I’m afraid you’ve got mice. Or meece, if there are a whole lot of them, or mousies if they’re especially cute. A lot of the nouns that are the same singular and plural, like bison, are animals, such as sheep, or deer, or fish. You can have fishes, but they’re usually biblical, and come with loafuses.
And sometimes the plural spelling of those animals is different depending on whether you’re chucking them under the chin or hunting them. So you might keep a bunch of rabbits as pets, but you hunt rabbit. (Or wabbit.) Perhaps people say they’re hunting elephant because they prefer to think that elephants are uncountable, which they emphatically are not. Shame on them.
But this business of dropping perfectly good esses is getting out of hand. We grow crocuses, not crocus. We plant agapanthuses, not agapanthus. Where does it end? Nasturtia?
You’d think this is the kind of thing that happens when you’ve scolded too many people for using extraneous apostrophes with their esses over the years. Maybe they’ve decided to skip the whole thing. But the apostrophe people are not the ones dropping the esses. They’re fine with the way they spell and punctuate, and feel it is helpful to give a plural noun a nice apostrophe to help hook the S onto the word.
No, it’s the people who strive to get it right that get it wrong. The first time they heard someone say “a bed of iris” they thought: Oh no. I’ve been saying irises all this time. But clearly this is some sort of Latin thingy and thus, because only erudite people know Latin, it is correct. And then they hear similar incorrect plurals, and rush to catch up to the erudition bandwagon.
And even so, nobody calls buttholes “ani.”
It’s hit or miss. Somehow we all know to say “asters” and “daisies” but go all to pieces over trilliums or dianthuses. We talk about mallards but suspect there are wigeon. I looked to the experts to find out why some things never take an S plural, and found this:
“They form a lexical category in Guiraud’s sense, that is, a non-arbitrary set of nouns with common features at the level both of the signified and of the signifier, and constituting, from a diachronic perspective, a matrix having enabled membership of the category to develop until today.”
Apropodes of nothings, the plural of bullshit is bullshit.