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Re: It's always worth it to go out (for Salamandra) ;-)

PostPosted: Thu Feb 23, 2017 10:37 am
by Bobby Bok
Awesome picture/observation!

Re: It's always worth it to go out (for Salamandra) ;-)

PostPosted: Sun Mar 12, 2017 9:35 pm
by Jeroen Speybroeck
While arvalis and berus are having a good time, a dry period interrupts my mandering fun. A good time to share a surprising observation I made during my last outing, 4 days ago.

Image

So far, all of my (not too numerous) amplexus sightings where in the period September-December, with half of them in September. A March mating attempt thus surprises. Temperature was high; maybe that got the hormones boiling...

Re: It's always worth it to go out (for Salamandra) ;-)

PostPosted: Sun Mar 12, 2017 9:41 pm
by Jeroen Speybroeck
Another fun fact - penultimate observation of the envolved female was at the end of January, when she was still gravid.

Re: It's always worth it to go out (for Salamandra) ;-)

PostPosted: Sun Mar 12, 2017 11:15 pm
by Ilian Velikov
Jeroen Speybroeck wrote:A March mating attempt thus surprises. Temperature was high; maybe that got the hormones boiling...


Maybe because the female can store sperm in her body and fertalize her eggs whenever she wants "amplexus season" might not be that strict...?

Re: It's always worth it to go out (for Salamandra) ;-)

PostPosted: Mon Mar 13, 2017 8:29 pm
by Jeroen Speybroeck
Yes and no. It is true that there is room for flexibility in fire salamander life history, yet certain activities do show seasonal patterns. But I guess this hardly surprises anyone around here. Whether it's all about girl power? Dunno... ;)

Re: It's always worth it to go out (for Salamandra) ;-)

PostPosted: Tue Mar 14, 2017 10:30 am
by Ilian Velikov
Of course, but it looks like the seasonal pattern can be even more flexible than we thought, and you've got the photos to prove it ;)

Jeroen Speybroeck wrote:Another fun fact - penultimate observation of the envolved female was at the end of January, when she was still gravid.


So was she still gravid now, I can't tell from the photo? Or did she deposit larvae first and then went on to mate again?

Re: It's always worth it to go out (for Salamandra) ;-)

PostPosted: Tue Mar 14, 2017 4:43 pm
by Jeroen Speybroeck
Ilian Velikov wrote:
Jeroen Speybroeck wrote:Another fun fact - penultimate observation of the envolved female was at the end of January, when she was still gravid.

So was she still gravid now, I can't tell from the photo? Or did she deposit larvae first and then went on to mate again?

She might have still been carrying some larvae, but (in contrast to the previous observation) she was not big enough to qualify as positively gravid. Trying to discern true trends only, I only label those females that are clearly carrying larvae as gravid. Larval deposition often (I think even most of the time, should check Thiesmeier's book) happens in stages, so at some point, some larvae may still be in there, even though I call her 'not gravid'.

Re: It's always worth it to go out (for Salamandra) ;-)

PostPosted: Wed Mar 15, 2017 12:11 pm
by Ilian Velikov
Jeroen Speybroeck wrote:She might have still been carrying some larvae, but (in contrast to the previous observation) she was not big enough to qualify as positively gravid.


I'm probably about to say something that is well known, so excuse me if that's the case but my knowledge on fire salamanders is limited.

So, assuming the scenario where she's still carrying some larvae but mates again it's fair to say that she doesn't need to mate at this particular time. So her urge to mate was triggered by environmental conditions rather than some genetically predetermined timing. Could the ability to store sperm and use it later be an adaptation to climate(s) with variable weather where seemingly suitable for mating periods could be followed by unsuitable periods for larvae development and deposition?

Re: It's always worth it to go out (for Salamandra) ;-)

PostPosted: Wed Mar 15, 2017 1:07 pm
by Jeroen Speybroeck
Yes on your closing question. To disentangle imprinted behaviour and environmentally induced behaviour, an experiment with wild caught animals in captivity would be cool. Until then, it's hard to say how big a role environmental variables play. Would have to run for multiple years, though, submitting different females to both conditions as in the wild as well as 'disruptive' ones. Funding, anyone? ;)

Re: It's always worth it to go out (for Salamandra) ;-)

PostPosted: Thu Apr 06, 2017 8:47 am
by Tomas Klacek
Hi,
eventually I made a gif from interaction photos which I promised in other thread. I guess both are males, am I right? One of them constantly tried to get underneath the other one and It also looks like he tried to flip him upside down.

Image

Here is the GIF (10.3MB)

What do you think about it? I never saw a salamander fight, so I´m really not sure, what I saw...
Thank you!
T.