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

PostPosted: Wed Feb 08, 2017 3:06 pm
by Jeroen Speybroeck
The recognition of my manders is done with ManderMatcher. This is a program developed by Koen Steenhoudt and myself. It can be downloaded for free through my website.
http://www.hylawerkgroep.be/jeroen/index.php?id=85
However, it is specifically conceived for S. s. terrestris, so it won't be of use for cristatus.

Apart from AmphIdent, you may want to check this out.
http://www.fupress.net/index.php/ah/article/view/17198
http://www.sciencedirect.com/science/ar ... 4115000680

Note that both papers deal with data collected within the span of a single year (or even a single season, in 2 of the 3 datasets). The first refers to a paper by Arntzen & Wallis 1999 to substantiate that the carnifex belly pattern does not change but (1) Drechsler et al. 2015 (= the description of AmphIdent) show that this is not true for cristatus (using 3 years of data) and (2) Arntzen & Wallis do not provide evidence for that statement.

While pattern changes may hamper recognition, it doesn't mean that the software is not useful! A clear difference with AmphIdent is that they are free. I have not used any of them myself (and I don't intend to enter 10,000+ records in a different system than the one I'm already using). When choosing, you may want to focus on comparing processing time and field time. Do you need to edit the photos? Do you need to photograph animals in a standard pose? Etc.

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

PostPosted: Wed Feb 08, 2017 7:05 pm
by Michal Szkudlarek
Jeroen Speybroeck wrote:The recognition of my manders is done with ManderMatcher. This is a program developed by Koen Steenhoudt and myself. It can be downloaded for free through my website.
http://www.hylawerkgroep.be/jeroen/index.php?id=85
However, it is specifically conceived for S. s. terrestris, so it won't be of use for cristatus.

Apart from AmphIdent, you may want to check this out.
http://www.fupress.net/index.php/ah/article/view/17198
http://www.sciencedirect.com/science/ar ... 4115000680

Note that both papers deal with data collected within the span of a single year (or even a single season, in 2 of the 3 datasets). The first refers to a paper by Arntzen & Wallis 1999 to substantiate that the carnifex belly pattern does not change but (1) Drechsler et al. 2015 (= the description of AmphIdent) show that this is not true for cristatus (using 3 years of data) and (2) Arntzen & Wallis do not provide evidence for that statement.

While pattern changes may hamper recognition, it doesn't mean that the software is not useful! A clear difference with AmphIdent is that they are free. I have not used any of them myself (and I don't intend to enter 10,000+ records in a different system than the one I'm already using). When choosing, you may want to focus on comparing processing time and field time. Do you need to edit the photos? Do you need to photograph animals in a standard pose? Etc.

how many salamanders are in your population? by 10,000+ records you mean 10,000 encounters, right? damn i wish i lived more to the west

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

PostPosted: Fri Feb 10, 2017 9:41 am
by Jeroen Speybroeck
As the CMR method does not work with juveniles, I can only provide numbers for adults (defined in my case as >14 cm individuals). My entire dataset currently contains 1841 adults. The standardised subset (animals collected along the same fixed transect, following the same method etc.) has 1506 adults.

The number of new adults is still dropping each year: 397 additional adults in 2014 (vs. 2008-2013), 221 in 2015 and 160 in 2016. Reaching zero is of course impossible, as each year a new set of subadults will become adult.

In this season (starting in Nov-Dec), new adults are mostly females, as they tend to roam around to drop their larvae. The start of autumn, however, has a lot of males looking for a mate.

Note:
(1) Some of these adults may have died in the mean time. Several are however still frequently recaptured since their initial capture in 2008. Most of those 'oldies' were already adult in 2008, so they should be at least ca. 14 years old.
(2) I'm doing a transect sampling. Even though I may be focusing on a subsection with more than average density, this means that the population is obviously much larger than that. Quick-and-dirty estimates of the part I survey: 1500-2000 ind/ha, a number which is up there with the highest density estimates available for this species.

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

PostPosted: Fri Feb 10, 2017 11:22 am
by Ilian Velikov
Interesting stuff, Jeroen!

Are there any other studies/publications on the lifespan of this species? 14 years sounds a lot, I didn't expect them to live that long.

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

PostPosted: Fri Feb 10, 2017 2:21 pm
by Mario Schweiger
Ilian Velikov wrote:Interesting stuff, Jeroen!

Are there any other studies/publications on the lifespan of this species? 14 years sounds a lot, I didn't expect them to live that long.


that's a teenager ;)
oldest published one was 50+ years.
Paper is in German with a short engl. summ.
http://vipersgarden.at/PDF_files/PDF-10173.pdf

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

PostPosted: Fri Feb 10, 2017 3:18 pm
by Jeroen Speybroeck
20 is supposed to be fairly commonly achieved in the wild. Those geriatric records, like the one Mario cited, relate to animals in captivity only. Hard to tell what a real/true life expectancy in the wild is - give me some time. ;)

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

PostPosted: Fri Feb 10, 2017 4:01 pm
by Ilian Velikov
:shock: That's impressive!

Excuse my ignorance but is such a long lifespan common in salamanders...or amphibians in general? I haven't heard of such a long-lived frog...

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

PostPosted: Sat Feb 11, 2017 7:29 am
by Mario Schweiger
Ilian Velikov wrote::shock: That's impressive!

Excuse my ignorance but is such a long lifespan common in salamanders...or amphibians in general? I haven't heard of such a long-lived frog...


have not the paper here now, but Bufo bufo 54+ years (came adult to captivity)

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

PostPosted: Sat Feb 11, 2017 12:41 pm
by Noah Meier
Jeroen Speybroeck wrote:The recognition of my manders is done with ManderMatcher. This is a program developed by Koen Steenhoudt and myself. It can be downloaded for free through my website.
http://www.hylawerkgroep.be/jeroen/index.php?id=85
However, it is specifically conceived for S. s. terrestris, so it won't be of use for cristatus.

Apart from AmphIdent, you may want to check this out.
http://www.fupress.net/index.php/ah/article/view/17198
http://www.sciencedirect.com/science/ar ... 4115000680

Note that both papers deal with data collected within the span of a single year (or even a single season, in 2 of the 3 datasets). The first refers to a paper by Arntzen & Wallis 1999 to substantiate that the carnifex belly pattern does not change but (1) Drechsler et al. 2015 (= the description of AmphIdent) show that this is not true for cristatus (using 3 years of data) and (2) Arntzen & Wallis do not provide evidence for that statement.

While pattern changes may hamper recognition, it doesn't mean that the software is not useful! A clear difference with AmphIdent is that they are free. I have not used any of them myself (and I don't intend to enter 10,000+ records in a different system than the one I'm already using). When choosing, you may want to focus on comparing processing time and field time. Do you need to edit the photos? Do you need to photograph animals in a standard pose? Etc.


Thanks for that input... Maybe I'm going to start with a manual recognition method for the first year (comparing results of caught specimens during migration and the ones I find by using water traps). If things develop positively I may start with any software later...
Anyway I'll keep you informed with the method I use and the results of course. ;)

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

PostPosted: Thu Feb 23, 2017 10:20 am
by Jeroen Speybroeck
Postponed autumn rains lead to unprecedented activity peaks at the end of 2016. Now that water levels are up again, larval deposition seems to take off (or rather: catch up?) more markedly than usual as well. Yesterday was a busy night.

Here's three ladies in and on there way to the water. Another two females were in and near the water within a 2-3m radius.

ladies.jpg

Total count number was more than 160. A clear new maximum for the Jan-Feb period. Goes to show that these high numbers are fairly possible throughout the year, given the right circumstances. In this case, 97% humidity and 9.9°C after a dry autumn. Moderate wind did not counter the effect of such an unseasonably mild temperature.