A big thank you to Pez for that reply! I'm familiar with those study results, but it's great to see them listed in one place.
Some points:
It doesn't take a million people to get a good cross section of society. A thousand is probably enough, but several thousand would be better. There's a penis size preference study that was done in 2006. It had about 23,000 female participants. That was by advertising the survey on a major news station website. So, participants were from multiple different states.
That's really the challenge in zoo sex surveys, getting a broad selection. "Selection bias" would be a problem if the survey was taken from a sex oriented website.
I think there may have been a small percentage not telling the truth on those surveys, but it's not a huge amount that people should be in awe about.
What percentage of women identify as Lesbian? Isn't it about 1.5% ? Well, you come across about as many zoo women in every day life as you do self identified women with the lesbian label (not counting bi women, or those that will not identify as other than straight, even though they are not straight).
I'm in a popular city, so the ratio is skewed here. I can't exactly use that comparison where I live, but.... some of you can.
Even if a higher amount of people are curious about zoo sex now after easier/more access to zoo stories, porn, romantic zoophile posts online, and..... animal peen shaped dildos to use as a baby step...... not all people have contact with animals, or can build a relationship with them. This is why numbers for males having sex with other animals besides dogs was likely higher in the past than now. There's not doubt in my mind, that if economics and secrecy (ability to hide it) did not factor in, there would be a higher percentage continually active. Basically 4% might be 8%.
Without a huge cultural shift in acceptance or respect for zoophilia, even increased proximity to animals would likely not bring the percentage into the double digits, in my opinion.
Edit:
Regarding studies on fantasies, Dr. Justin Lemiller wrote a book called Tell me What You Want. He surveyed 500 something people, from a wide variety of backgrounds, in the last 10 years, about their desires and fantasies. He said that he was surprised at the amount of taboo fantasies, some of it zoo sex. I don't have the stats handy, but the numbers can be seen. Of course, that is about fantasy, but.... I'm of the opinion that a good many people would try their fantasy out for real, if they had both access and the ability to keep it a secret, or private enough.