We have had five tadpoles for over 3 weeks. And now have six! I thought I was imagining things. When I can't see them I nudge the tank to make sure they're ok an this morning did that and sure enough they all appeared. I count to check they are all still alive. Counted four - then the fifth one appeared and then another one! All in plain view so I didn't miscount.
My poor brain was thinking bizarre and wonderful ideas
1) The mosquito brought a tadpole with him
2) A tadpole wriggled his way here and found his friends
3) One of the tadpoles gave birth
4) Next doors cat got in and dumped another tadpole in there
5) Someone else dumped another tadpole in there, knowing we had a tank! (It's in the outside porch)
As all these options are virtually impossible I then thought - the sixth tadpole is much smaller so
5) One must have been piggy backing under another one (I'd have noticed)
6) One must have been permanently attached to one of the river rocks we brought with them (I think I'd have noticed).
7) One has hatched out and there must have been a bit of spawn in the water.
I am thinking it must be number 7 as the sixth tadpole is smaller. Is is possible a bit of spawn has been attached to a rock? The two rocks in there came from the area of river where we found them along with their river water.
For the first 8 days they were in their river water - I then scooped a bit out and added some fresh water. Did that a couple of times. After 3 weeks I changed the water completely. And there were only 5 tadpoles then - I have a photo of them!
So can only think a bit of spawn was attached to one of the rocks and has hatched out.