Tarantulas are capable of going for an extended period of time without eating. While this may be of little or no concern to the tarantula, it can sometimes be stressful for the beginner keeper who believes they are doing something wrong and endangering the health of their pet.
"Help, my tarantula hasn't eaten for days/weeks" is a common post on many tarantula forums, so I wanted to address the issue here. First of all, if your T isn't eating don't panic! As has already been stated, it can for a long time without eating without any concern. There are several reasons why it might not be eating, so let's take a look at each of them in turn:
• Newly acquired – you should let a new tarantula settle in for at least a few days before offering food. If your T isn't eating and it's only been a couple of weeks since you got it, just give it some more time and try offering food once per week.
• About to moult – Is your tarantula due to could soon? Tarantulas will tend not to eat for several weeks before moulting, and shouldn't be offered food for a week after moultig (see below for more details)
• Cold temperature – Is it winter? A tarantula's appetite will tend to be reduced during the cooler months so refusing to eat over the winter is nothing to be concerned about. Just offer a cricket once every 2 – 3 weeks until it starts eating again.
• Doesn't like your offerings – Some tarantulas are just a little fussy, and don't like certain foods. If you've been trying a certain type of prey for a while with no luck, try something else which might just tempt it to bite!
• Is the food too big - Tarantulas may refuse food if it is too large for them to comfortably take down. It is a good rule of thumb to offer food the same size or smaller than the tarantulas body length.
Is the food new to them - Many tarantulas who have never eaten dubia roaches or any new food will often refuse to eat them at first. When introducing new food use smaller feeders as they are less intimidating. Make sure the tarantula is hungry. If the tarantula refuses to take the food try again. It has taken multiple attempts for some of my tarantulas to eat dubia. Once they take the dubia, the tarantula seems to remember and recognize it making future feedings much easier.
No matter what you try, some tarantulas will just plain decide to fast for an extended period of time. The Chilean Rose (Grammostola rosea) has a real reputation for doing this, which is a regular source of concern for beginner keepers. As a general rule, so long as your T doesn't seem to be losing much weight there's nothing to worry about. Just keep offering a prey item every few weeks (and removing uneaten prey after 24 – 28 hours) until it starts to eat again.