As in baby toucan smoothie? 
I’m going with this answer for my sanity not the one below yours
Native plants. As in, the kind you purchase to put in your yard. Because they’re often native to an entirely different area, maybe hundreds of miles away (Texas is a big state - some people label all plants that grow in the state as native and put them up for sale). Even plants sold or planted by more knowledgeable organizations that are labelled are often not native to the area - they’re often native to one or two eco-region to the east or west, or south or north. They were not historically found in the area where they are being promoted as having grown.
And then, even if you buy something that you know is historic to your area… the genetics of the plant or seed you have purchased likely don’t match your habitat. They might be from a few eco-regions away!
While I don’t prattle on about this too much, I have perfected an invisible grimace when I hear people cheerfully talking about the native plants they have purchased recently.
Well, the success of invasives suggests that being from a few ecoregions away might be an advantage. When you have a species that is endangered in its original habitat and invasive somewhere else, it sometimes seems like the solution to species conservation is simply to move them from where they don’t thrive to where they do. When every species has been relocated to where it does the best, we won’t need to keep spending money on habitats where they weren’t doing well.
Ok, clearly, I’m far less controversial than most. I usually just bore my friends with things like, “See that butterfly over there? That’s a such-and-such hairstreak. Know how you can tell? See that little spot? No, the one next to it . . . Yeah, well, note the size. It differs from the other such-and-such hairstreak by the size of the spot. No, that hairstreak is gray too. No, that spot is also blue. Oh that reminds me. You know those blue butterflies that often land on animal crap? Well, they . . .” Usually, my friends nod politely, wander off, and find me later when it’s time to go to the car.
It’s finding that balance, where the species is no longer endangered, but it is not putting others species at risk, that is so difficult. Unfortunately, it is easy to tip the scale in either direction for any species.
I’ve been disappointed to discover how many of the wild plants I grew up with have turned out not to be native, and inversely, realizing how the different the northeastern woods must have been when they were full of elms and chestnuts. I’m not at all offended by anyone providing this information, though, I wouldn’t be interested in nature if I didn’t like to learn.
https://thatlldont.com/products/plover-plover-plover
A really cool T-shirt by a local company. But it’s not the local subspecies. Most of the NT has Vanellus miles miles which definitely doesn’t have black shoulders. V.m.novaehollandiae is the one with black shoulders.
And I only realised because I went through the entire Vanellus taxon in my state.
Hmmm looks suspicious. I am put off by the three toes and yellow tint, and my brain says it’s AI, though I don’t trust myself enough to confidently say that.
Legs should be red for lapwing plovers too no matter what the subspecies. How hard is it?
Japanese knotweed is notoriously bad - and yet I had someone tell me they weren’t going to try to remove it bc “it attracts so many bees”
I still internally twitch thinking about that
Finding Nemo - the fish are beautifully accurate - at least aesthetically. BUT THE BIRDS ARE AMERICAN SPECIES WHYYYY??
oh no, I was considering buying that shirt too. I think I’ll get the Black/Whistling Kite “Stay Lit” shirt instead.
This may have already been done, but I’m going to share it anyway.
I was driving home with a colleague of my dad’s after we had finished a day in the lab. She was telling me just how much she loved honey bees, and that she thought they were so beautiful.
I could have refrained from this, but I burst her gorgeous bubble by telling her about how honey bees are nonnatives who actually compete with native bees and cause them harm. She was completely aghast.
Duck mating behaviors. I think this has been mentioned before, but I felt like adding it all over again.
I also tend to start talking an awful lot about leeches whenever the topic comes around, and I end up explaining how they bite, suck the blood, swell up, etc. There’s nothing wrong in it, but I suppose I’m not too great at describing it.
I do like to elaborate on the dimorphism in most bird species whenever I get the chance, for absolutely no reason, and even though no one has admitted it yet, I’ve bored my friends almost a dozen times by stopping by to say how the purple sunbird male is all sparkly while the female.. not so much, and the same goes for peafowl.
I also felt so glad after seeing so many people share how they point out native and non native species 
Pairs of Northern Cardinals on Christmas cards. “They’re both male. Don’t you just love gay cardinals?” I’ve shared this information several times with the deliberate intention of ruining things for people who I knew would be horified by it. Lol.
(This whole topic is reminding me of watching any historical drama with my teenagers, who are obsessed with historical clothing. “This is supposed to be set in 1828 but sleeves like that weren’t around until at least 1832!” Lol)
snerk
One of my other obsessulations is Early 20th Century women’s history and the fashions that went with the social changes. I have ranted at length about a film set in 1910 putting one of the female characters in an 1881-1882 Natural Form gown, when the scene involves a rather dusty hike.
I think I’d get along with your teenagers. 
Oh my goodness! This is exactly my college-aged daughter. And don’t get her started on the hairstyles. Ha!Ha! My young adult son has his own things he likes to pick apart during movies. Maybe I shouldn’t feel bad for “ruining” nature stuff. 
@GothHobbit You would certainly get along with my daughter! One of her main rants is the impracticality of many “historic” garments portrayed. She always says, “They weren’t stupid.” (As in people in history weren’t stupid so they would wear an appropriate garment for the occasion.)
there is a scene in Our Flag Means Death where Stede Bonnet gets excited by the sight of a moth, he describes it as Dryocampa rubicunda - which is appropriate for the location, but not for the time!
I was glad they used a real binomial name, though.
Ooh, historical iNatting—this could open up a whole new way to ruin things! 