I know this is just a meme and a pretty funny one at that, but my autistic ass with a science degree simply must mention that behaviour observed in captivity is not necessarily indicative of behaviour in the wild.
Go read the study though it's a very cool read and easily found online.
"I didn't ask if you can 'tell' they're having sex, I asked if you can CONFIRM sex. Are we two men standing in a swamp watching two gators maybe hump, or are we goddamn SCIENTISTS looking to understand the nature of sexuality as presented in the wild? Because I put my Science wellies on this morning, unlike someone who CAN'T CONFIRM TO ME IF THIS IS ALLIGATOR HOMOSEXUALITY OR NOT!"
Were the results corrected for observation time? If male/male mating takes twice as long as male/female mating then the probability of observation should double.