Anyone Know The Life Span Of Marine Hermits?

[littleme1969]

As the title says
It seems that most of my hermits have died within the last 3 months. All other inhabitants are fine including snails.
I bought tham all within a few months of each other and they would now be about 2.5years old. Was just wondering if that was the lifespan for these little guys. I had the blue legs, red legs and a few other misc in the 100g tank.
I first noticed the lack of the little guys when my hair algae suddenly started to get out of hand.

 

[Donya]

Depending on how big/old they were when purchased, it could be that they were old, although it doesn't really rule out the possibility of hermits killing each other or some other predator. The easiest to see indicator for when hermits are hitting crabby old age is the shedding cycle. When they stop growing and start shedding very infrequently, that's usually a sign of heading towards old age. The same is true for a lot of other arthropods. Behavior can also change, and they'll become less interested in fighting over food, etc.

 

[littleme1969]

Well that makes sense as I hadnt seen a shed for over 8 months and they also seemed more content to just graze rather than fighting. They all stopped growing almost a year ago , I noticed that they weent upgrading their shells anymore.
As for predators.. no I dont think so as I actually found one dead in his shell with no damage what so ever. I'll just stick it down to old age then and buy some more when this snow finally stops Thanks for the info