floating M. a. alpestris larvae

3 of my M. a. alpestris larvae have gas bubbles in their abdomens, forcing them to float to the surface, sometimes in an upside-down position....
Any idea what is going on here ?!?!
thanks
d

This is a common problem, but unfortunately I don't know exactly what causes it. In many cases, the larvae can recover from this. Keep them in shallow water (or in a container thick with plants) so that they can hold themselves upright.

bad news to my M. a. alpestris

in the same tub where i fist spotted the 3 floating larvae yesterday afternoon, i found 3 dead/dying this morning and 3 still float. i can think of a couple of factors which might have taken part:

the last daphnea feed had a large portion of floating daphnea - maybe the tadpoles gulpped-in air as they ingested the daphnea, and maybe haven't yet perfected a mechanism to expel that air?

the wheather changed from dry and stable to wet and unstable. perhaps a drop in atmospheric pressure allowed pre-exsisting bubbles in larval abdomens to expand and pull the larvae to the water surface?

in this tub only, i have spotted and removed a waterbaotmen yesterday afternoon. might it be responsible to the 3 mortalities (non-floating larvae)?

help !

over the last 24 hours i have lost more than 2/3 of my larval population to an unknown factor. bits or hole limbs disappear, debry sticks to their skins, some float, they die pretty quickly, and are covered in what looks like mould withing a few hours. looks like i am going to loose them all, soon.
they are M. alpestris a., some have hached as long as 2 weeks ago, some are only a few days old.
desparate situation. any ideas please?
d

if they have something growing on them check the ammonia levels, and if limbs are missing check if there is any thing else in the tank, and try to stableize the temperature so they aren't freaking out.

dying away...

what would be the connection between ammonia levels and growth ON newt larvae ?

one reason larvae float can be lack of food and missing limbs may suggest predation on each other ,also another good point was the temperature ,alpines don't seem to like it too warm. Maybe try sorting them into different sizes to cut down on predation...

they are dying like flies....

Thanks Ian.

The water temp' was never high. I suppose 20C would be the very maximum, hovering most of the time between 13C-18C.

Hunger is unlikely as they (used to be) surrounded by edible food. I havent fed them now for a day or so as a step of precaution. They start their deterioration and die on full tummies; food is obvious through their guts.

They are arranged in age groups tubs, and even size differences and deformations from hatching don't seem to be a factor in the severity and/or likelihood for mortality.

I had a suspicion the new food culture from a pond would have something to do with it (lots of different predatory pond creatures), but a stow-away newt larva from the pond survives happily in the culture... Could that (different newt species) larva be immune to something?

The dead bodies seem to be almost instantly covered with fuzzy stuff. That might suggest a microbial pathogen already hard 'at work' prior to death.

One last interesting point:
Larvae with bloodworms in their tubs, and larvae in the parent tank (well stocked with an extensive range of other invertebrates) seem to suffer less numerically. Could the sterile conditions of the tubs be disadvantageous?


D

i always say keep water changes to a minimum, others will tell you different but i do few water changes when the larvae are small and have a good success ratio, especially Triturus species seem to suffer from sterile conditions. I raised 115 mamoratus last year in a four foot tank which i had "seeded" with daphnia and other small food and whilst they were small never did a water change..plenty of elodea , duck weed and light, the larvae don't mind strong light and it helps the daphnia, keeps them alive and breeding by causing green water on which they feed...ian

agree

i absolutely agree with you there, Ian.
D

I had a long reply typed out, but the software just lost it for me. Ugh.

This might help narrow down the possibilities:
http://www.caudata.org/cc/articles/why_larvae_die.shtml

Sterile conditions don't work as well as "dirty" (cycled, planted) conditions. It can work, but you have to keep really clean, changing both the water and the container to fresh every couple of days.

When larvae suddenly begin to die off in large numbers, the immediate "first aid" that I recommend is to move all the survivors to a clean container of clean water.

link

Hi Jannewt,
thanks very much for the helpful link. sounds as if my larvae are contracting a desease to me... maybe too late to act?
D

bloodworm blood-line?

It may well be circumstantial, but it seems rate of mortality slow-down observed today coincided with the introduction of blood worms to larvae tubs. Could they be acting as some purification (feeding on malicious microbes), or water quality (creating currents) improvers?