It's only 5%? I'd have sworn it must have been higher. I used to bring one male and 3-6 females of every bird species, and it seemed like every embark would end up with at least one species that would not reproduce. At 5%, that should mean 13 species before you hit a 50% chance of at least one non-reproducing species. Which I should have been hitting once every other embark. Must have been a long string of bad luck. As expected, bringing 2 males pretty much eliminates the problem, appearing maybe 1 in 10 embarks, and gives the butcher something to do.
But dogs! Seriously? They will mount your leg, a couch, an end table, pretty much anything.
It is irritating, though, when I'm playing a dead civ, so will never get replacements, and it turns out I find out why the civ died out. I have enough trouble getting Urist to put his socks on before putting on his shoes. If I knew that was the situation at embark, I'd abort the game and get a new team.
As long as it takes to generate a world, and select a starting location, then get a colony started without getting overrun by lycanthropes or wiped out by rain, seeing it die out from something like that is lame. If Toady gave a slider option, I'd have that puppy slid all the way.
[EDIT]
Re: the suggestion, how would that work? If it's pulling from the raws and generating randomly within those parameters, doesn't that imply that if if rolls a result you don't want, you can't change it? Or something more superficial than that, kind of like renaming the dwarf? Check or uncheck the box and you now have a fertile member of the clan? Well, I guess that's one way you could control the size of the clan without an externally-imposed pop limit.
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