Do shrimp have a circadian rhythm?

[Shrimple minded]

My shrimp tank is in my office, which has some (but not much) lighting on approximately 8am-1am.  My tank lights run from 2pm-10pm.  

 

Do shrimp need periods of complete darkness to breed well, or can they molt & berry in the daytime?  I'm just wondering if my own poor sleep habits are having an effect on the rate at which my females are berrying.  My shrimp are molting just fine, but I can't say I've every seen it take place with my own eyes.

 

I'm not 100% sure, but I think my one berry to date occurred on a weekend where I was out of town, meaning the only light hitting the tank was the 2pm-10pm photoperiod.

 

Thoughts?

[DETAquarium]

This is a good question, I would have to assume they would breed either in dark or light. I think some people do introduce to much light into their aquariums that could potentially stress their shrimp, and in turn reduce their breeding. 

[Soothing Shrimp]

It would be an interesting experiment.  Simple too.

 

Tank 1: 24 hours light

 

Tank 2: Day/Night

 

Tank 3: Full darkness

 

See which tank has the most breeding in a given amount of time.

[gillznglass]

I read a paper on another type of shrimp studied that most definitely concluded they do have a circadian rythim and it did affect their breading dramatically.  I can not find any studies on the type of shrimp we have. So let's get the geek glasses out and go to work.  I would be inclined to think all living creatures do have somthing that resembles it, even those that live in complete darkness. There are all types of energy we can not see that those animals may be in tune with. OK enough woo. Cool subject. 

[Jadenlea]

Imagine the Algae in Soothings tank 1!!  It might be hard to tell if breeding results were from 100percent light or 100 percent algae hehe

[Jadenlea]

oh and about 8 months ago when Igot my current plus lighting with the moonlight timers.. I wondered if having daylight and moonlight (rather than 100 percent darkness)  would stress the shrimp or cause a slow down in breeding.    They still bred like bunnies.  To bad no babies could survive in that tank.

[Soothing Shrimp]

Imagine the Algae in Soothings tank 1!!  It might be hard to tell if breeding results were from 100percent light or 100 percent algae hehe

 

I never said the experiment was foolproof! LOL

[Shrimple minded]

Not a controlled experiment, but I thought I would relate the following.......I was out of town on Wednesday & Thursday of this week, (meaning my office lights were off the full time and only the 8 hour photoperiod of the Finnex Stingray)........I came home to a berried female.  Prior to that I hadn't altered my own sleep schedule, thus I hadn't for the skrimps.

 

I'm starting to be a believer.......