I was able to breed about 200 tadpoles last year, I released most of them in my little pond and kept 12.....5 were males and 7 females. The males throat turned dark at about 6-7 months...and they started to croak around early April. When I separted the males I kept one and thats when he got really really loud....and trust me they are VERY loud. The 4 i released that night went crazy outside and croaked like maniacs for months until about a month ago it all got quiet for now...When I water the lawn at night and it's a cold night..i can sometims hear them croak a bit....they love the cold...go figure.