Triturus marmoratus - a peculiar massacre

marblenewt

New member
Joined
Feb 29, 2016
Messages
4
Reaction score
1
Points
0
Location
Portugal
Country
Portugal
Hello everyone.

With this thread I would like to expose an incident, of so far unknown origins, which took place (and might be ongoing) in a specific region and has apparently culled the population of the adult species in question. I initially contacted European individuals in attempting to obtain some help on what was causing not just so many deaths, but deaths in a strange fashion - to amphibian enthusiast or not.

The little information that I sent turned out to provide little context, and, without this, some speculation was working on unlikely situations and wrong assumptions. In a attempt to remedy this, I produced a small report going over the necessary details I imagined are needed for someone attempting to think of the problem from a distance.

There is ongoing discussion (in Italian) at Forum Natura Mediterraneo, on this thread, which has been reacting to the content in the document provided here. I hope that here the same can take place in English.

In creating this thread, I am starting a discussion for those who can point out the reasons for this mortality, so that I won't actively participate unless specific questions need to be addressed regarding my experience with the event.

That said, the pdf document exposing the situation can be downloaded here, through Google Drive. I have assumed it pedantic to repeat any of its content in this thread.

Thank you.
 

garfield188

New member
Joined
Dec 22, 2011
Messages
27
Reaction score
0
Points
1
Country
Netherlands
Could it be the newt killing fungus Batrachochytrium salamandrivorans?
 

schmiggle

Member
Joined
Oct 7, 2015
Messages
88
Reaction score
2
Points
8
Location
Massachusetts
Country
United States
This is very sad. I hope the problem is solved soon. My gut reaction was that it was human caused, but perhaps that is unsupported by evidence (I can't read Italian, so maybe that was discussed on the forum linked to by the OP).
Bsal does not cause newts to become eviscerated, as these were. They just get massive lesions and die.
 

Chinadog

Super Moderator
Staff member
Joined
May 8, 2013
Messages
2,685
Reaction score
73
Points
48
Location
Chesterfield, England
Country
England
Welcome to the site marblenewt. :)
I've moved this thread to the ecology section as the topic may well involve other wildlife.
I remember seeing a TV programme about the mutilated Bufo toads, I think it may have been Animal X on the BBC, it will be very interesting to see if this case is similar.
 

marblenewt

New member
Joined
Feb 29, 2016
Messages
4
Reaction score
1
Points
0
Location
Portugal
Country
Portugal
Hello everyone.

I have news regarding the case of the newts. It turns out that very similar depredation has been documented in the last decade, and the principal culprit might be a surprise; the otter (Lutra lutra). The otter, perhaps along with other mustelids, seems to be quite capable of manipulating amphibian prey and being very particular as to what it consumes. While newt depredation is more or less newer, that regarding toads is decades old; part of the type of prey handling exhibited by otters on toads has been termed progressive skinning and skinning behaviour. A documented instance of depredation on Pleurodeles waltl by otters fits the type of ventral cuts visible in the bodies of the Triturus marmoratus I photographed. For the moment, it has been difficult to ascertain how and why an otter would travel to the area to consume marbled newts specifically, which has opened consideration for two other mustelids; Mustela putorius and Neovison vison. The latter considered more credible and likely due to its diving capability. Scavengers that might have caused (extra) mutilation, such as Corvus corone, have not been excluded for that role.

For those interested, here's some relevant literature:

For the best example (so far), in terms of similarity, of depredation of newts by otters see Impact of otter (Lutra lutra) predation on amphibians in temporary ponds in Southern Spain

For the otter as toad predator see PROGRESSIVE SKINNING OF TOADS (Bufo bufo) BY THE EURASIAN OTTER (Lutra lutra) and Seasonal use of ponds as foraging habitat by Eurasian otter with description of an alternative handling technique for common toad predation

For generalized newt predation by otters see Predation of newts (Salamandridae, Pleurodelinae) by Eurasian otters Lutra lutra (Linnaeus)


Thanks.
 

xxianxx

Well-known member
Joined
May 19, 2011
Messages
2,683
Reaction score
97
Points
48
Location
South Wales, Gwent
Country
Wales
Display Name
nai live
Interesting articles, I have seen hundreds of degloved frogs and toads over the years at my local reservoir and always thought the likely culprits were foxes and mink. Havent seen any otters or otter scat there and I am familiar with seeing both having fished the wye since childhoood, the very occasional one passing passing through has been reported a hand full of times in twenty years but they certinly dont form a permanant or seasonal population.The predation reported by the op could have another species or series of species involved. Will definitely be doing some further reading and follow this thread.
 

JM29

Active member
Joined
Nov 16, 2009
Messages
389
Reaction score
52
Points
28
Location
Brittany
Country
France
Ironically, the general improvement of water quality in my area do favors re-colonization of rivers and body waters by the otter.
Amphibians will have to face another problem.
 
General chit-chat
Help Users
  • No one is chatting at the moment.
  • Chat Bot:
    liz. has joined the room.
    +1
    Unlike
  • Chat Bot:
    liz. has left the room.
    +1
    Unlike
  • Jaeger:
    My axolotls were doing fine until the cycle int heir tank crashed. I currently have them tubbed and they wont stop shedding their slime coat, and my golden albino looks a little red, and his gills dont look too good. Theyre both flaoting and im keeping the tub at 18 degrees celsius and doing 100% water changes everyday, any help on anythingelse? can anyone help?
    +2
    Unlike
  • AkemiYousei:
    @Jaeger I would try to double up on Prime to combat the slime coat shed when doing the 100% water changes. Also, if it's bad, might want to consider a tea bath as a preventive measure.
    +2
    Unlike
  • AxolotlMama:
    I just wrote this on the post ^
    +2
    Unlike
  • AkemiYousei:
    Haha, great minds, right?
    +2
    Unlike
  • AxolotlMama:
    They sure do 😄!
    +2
    Unlike
  • Jaeger:
    @AkemiYousei thanks so much. Will do. I have also given them a tea bath before, seems to work their gills are looking so much healthier, my golden albino is swimming around frantically trying to jump out, should i be worried? my wild type is fine
    +2
    Unlike
  • AkemiYousei:
    Might be the stress, or the shedding bothering it
    +1
    Unlike
  • AkemiYousei:
    Make sure s/he can't jump out, and maybe keep her in a undisturbed, darkened place for a bit. See if that calms the goldie.
    +1
    Unlike
  • Unlike
  • Chat Bot:
    KOsika has left the room.
    +1
    Unlike
  • Jaeger:
    I woke up to my golden axolotl covered complete white. what do i do
    +1
    Unlike
  • Jaeger:
    Just found out, hes dead. :(
    +1
    Unlike
  • mcapanema:
    :'(
    +1
    Unlike
  • AkemiYousei:
    @Jaeger, Oh no! Sorry to hear. :(
    +1
    Unlike
  • AxelTheAxolotl123:
    my axolotl has white balls on its gills and the feathers have shrunk
    +1
    Unlike
  • Jasper2021:
    We have an axolotl called Jasper who is approx 3 years old. He was being attacked by his companion so we separated them. He has healed his wounds now but has got very thin. his lips have turned black. he was just looking still and dead at times but ears moved so we knew he was still alive. Hold earthworms right in front of him which after some time he will take you think good he is eating but then it pops straight out again. At the moment he is in the fridge. Not sure what else to do if he can't or won't eat !!
    +1
    Unlike
  • Wyn1993:
    Hi Jasper 2021,
    +1
    Unlike
  • Wyn1993:
    I am new to axolotls myself and one thing I learnt was that earth worms when in distress give off an awful taste - have you tried live river shrimp? Mine really like these and are always happy to 'bite' - I also give them live crickets and pellets which are really pungeant in smell and they always take these - even wait at the glass for them! So sorry to hear he was being attacked by his companion!
    +1
    Unlike
  • MelissaKenyon:
    Hi, just wondering if anyone could help with our axy, she absolutely loves her food and we've notice tonight after her worms( that she ate in one mouthful) that she ue was struggling to get up to the top for air. She's never done this before, she usually goes up every 5-10 mins or so. She is 6 months old and seems very healthy. Could it be a problem with our water level or water quality or could she just be to full?
    +1
    Unlike
  • Chat Bot:
    MelissaKenyon has left the room.
    +1
    Unlike
  • Chat Bot:
    MelissaKenyon has joined the room.
    +1
    Unlike
  • bearbear_13:
    I posted a thread about my axolotl if anyone is able to help me out!
    +1
    Unlike
  • bearbear_13:
    She’s not eating, her tail and gills have shrunk, she’s lot a lot of weight, and we’ve checked her water levels with no negative results
    +1
    Unlike
    bearbear_13: She’s not eating, her tail and gills have shrunk, she’s lot a lot of weight, and we’ve checked... +1
    Top