Drawing from my knowledge of other geckos, the tail wag can mean a great many things. It often precedes striking, yes, but it is also used as among-individual communication. It may indicate submissiveness or be a signal of dominance - it’s hard to know. I think there’s also something about it being a mode of wafting pheromones, which would tie well into its role in mating behaviour.
With these guys, and I definitely trust Mark’s opinion over my own, the tail wag to me seems either territorial or as part of an evasive maneuver. I think that waving that big fat tail looks pretty threatening and especially when paired with back arching it seems territorial to me.
When paired with slinking movements/running it seems more to distract your attention toward the tail and away from the head. My gecko has actually also done it while walking backwards before which is kind of where this belief came from for me.
We interrupt your regularly scheduled program for this totally unnecessary review:
I recently decided to try Phoenix worms for my gecko since I’ve always had trouble getting him to take mealworms etc.
I have just received them in the mail and I do not know yet whether or not Elmo will take them but I’m more going to talk about the service.
The price for a 100 count of medium sized phoenix worms was less than 5 dollars and the shipping was just over 5 so I decided to give them a try.
They were shipped from Southern California all the way to Southwest Florida.
My order was shipped the day after I placed my order and my order arrived in 3 days, the first day of the estimated delivery period.
Not only was my order handled promptly but when I checked to see the survival rate (as it’s beginning to get a bit hot again) I saw not a single dead worm.
They were all incredibly active and well fed.
All in all: 10/10 would order again