CRS breeding in winter

So, what are they thinking in the merciless Canadian winter?

 So I have moved most of my shrimp tanks in my new shrimp room (started cycling in July 2013), it's in a small 10'x14' room in the basement. The breeding had been great from the beginning, all shrimps were breeding up until late October when the room temperature dropped to 18 - 19C (~65F). The babies kept growing although very slowly, and breeding slowly slowed down.

I have less than 10 shrimps that got berried in December, and I have probably over 500 bee shrimps in the shrimp room. And less than 5 in January.

What's going on?

I remember although breeding slowed down, but I had way more berried shrimp last year in tanks I had heaters in. This year it just slowed down to almost a full stop.

I have a CRS tank in my living room. The population grew from 3 to about 150 between March 2013 and November of the same year. I also observe no berried shrimp in that tank. Before November, female shrimps constantly got berried.

A lot hobbyists contribute this to barometer changes in the winter. I can't disprove that, but it doesn't explain why breeding still goes on in my buddies' shrimp tanks, but almost every tank in my house slowed down.

Hope things will pick up again soon. My experience tells me March is the magic time. I will just convince myself it's just a matter of time like I've told others countless times.

Share your experience?