P. chinensis behavior

Basing my sexing on tail lengths, I have 2.1. All three animals are setup in a 20 H (24") tank. I have an elongated piece of driftwood on the bottom along with a healthy portion of java moss. There are two cork bark sections that serve as floats. All three animals seem to have acclimated well and feed well. One of the males spends almost all of the time in the water however while the other two remain on the floats, rarely entering the water. I have not noticed any obvious aggression however I remember reading in another thread that this species may be somewhat territorial. I am curious as to whether or not I should add more hiding places underwater? I do not like to make my enclosures too complicated because it becomes easy to miss debris when siphoning. Any suggestions?
Chip

Have you tried placing the more terrestrial of the two in the water alongside the aquatic male and seen how they interact? In my experience animals subjected to aggression will leave the water to avoid conflict (perhaps migrating across land to another river pool in the wild???) Two males in one group does make aggression likely. Males will also attack and drive away females that enter their territory, so it may be that the aquatic male is bullying both the other newts. If aggresion is the problem, separation as early as possible is the way to go, as long exposure to attacks can lead to rapid deterioration in condition, which is very hard to reverse.

It may be that a two-foot aquarium is simply not large enough (I had a large male P. fuzhongensis that would never settle down in anything smaller than a three-foot).

Do the animals swim frantically at the surface of the water, leaping out if you drop them in the water? This could indicate a water parameter problem, but if one animal is in the water this doesn't seem likely.
What are the temperatures like? Low temperatures can cause this behaviour as well as high temps.

Try providing caves formed from a flat piece of rock supported at each end by other stones, with a couple of tiers of caves. In my experience, Paramesotrion are far more confortable when such rocky hides are produced. They are simple to take apart for cleaning, too.

Sorry for the flurry of fairly unrelated ideas, but these are all things that have been linked to leaving the water in my experience.

I appreciate your input Chris. The other two rarely go swimming but do enter the water on occasion. They have been in this tank for about two months (which is how long it has been setup). Before that they were in a simple quarantine enclosure with just a few inches of water and a couple of floats. During that period the female usually remained under water, often hiding under the same float as the male. The temperature fluctuates from around 66 - 71 f, depending to some extent on the outside weather. I have yet to try forcing the other two into the water however they do enter on their own on rare occasion. I will try adding some more hiding places to see if that helps. Thanks again.
Chip

I completely agree witch Chris but I can`t resist sharing my experience. Chinensis are pure rowdies but their interactions does not seem such harmful as in a case of the other species. I`ve been keeping 2,2 together for 4 years and it has never induced any injuries. Contrarwise they have never bred.

Juraj: I have found simlar things with P. aff fuzhongensis; they don't injure one another (as seen in eg deloustali) but once one animal has asserted dominance, it will continually bully the inferior animal, causing it to become skittish, stop eating, leave the water and become more susceptible to disease (perhaps as a consequence of starving). Tiny injuries that fights leave, which would normally clear up, become infected. Once they've reached a certain point they become very hard to even rehabillitate in separate enclosures.

I also had one case of an animal that ate well, but rarely entered the water, never put on weight a finally died suddenly. It turned out that she was carrying a heavy parasite load.

When you add hiding places, provide some very close to the surface in the form of stack of rocks. Mine liked to hide in nooks just beneath the surface so they were hidden and submerged, but could slip out for a breath very easily. Stands of Vallesineria sp. (I am unsure of the spelling - the commonly available aquatic plant) are also appreciated, particularly for egg laying.

Sorry this is so annecdotal, but just a couple more thoughts to throw into the discussion.

How are they doing now?

Chris

my P hongkongensis often wrestle at mealtimes, sometimes they stay in a tight ball for minutes, biting legs and tails as they roll around, no injuries ever occur though.
Also,,, if you ask me,, a healthy tank isn't nessesarilly one that is free of detritus, there's quite a bit in mine.

After more observation I notice that the female does enter the water fairly often but never seems to be as aware of my presence as the dominant male (I have decided that is what he most likely is after reading these replies). I have pushed the smaller male into the water a couple of times now and it always immediatly crawls back out. For the short term I plan on adding some more hiding places however I have a 50 gal breeder tank that I can switch them over to later this summer. Also, when I speak of siphoning debris I am referring to any uneaten food (which is rare) and fecal matter, neither of which are desirable in an aquarium.
Chip

I have to agree with the previous posts.... aggression is not always obvious in this species but still very much present. I had two female chinensis for a couple of years. I had always kept them separate and they were both very aggressive, interactive newts- Always under water, good eaters who would come to the side of the tank and follow me around when I was in the room. Well I decided to try to put them in a large tank together and see how it would go. I figured, both females, shouldn't be too many problems. I watched them meet each other and the one female bit the other's leg, and the one who's leg was caught just relaxed and floated. Then the dominator let go, that was the whole interaction I ever saw, but from that time on the whole tank belonged to the dominator and the other newt stayed at one end of the tank or out of the water. I ended up separating them and then the submissive one went right back to being the way it was before......

What was the size of the tank that you used to combine them?
Chip

I had them together in a 20 gal long tank with a lot of hides and plants.