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
0
Country
Netherlands
Could it be the newt killing fungus Batrachochytrium salamandrivorans?
 

schmiggle

Member
Joined
Oct 7, 2015
Messages
88
Reaction score
1
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
63
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
2,568
Reaction score
55
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

Member
Joined
Nov 16, 2009
Messages
230
Reaction score
9
Points
18
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.
  • sde:
    Caudata.org chat? Haven’t seen this in years
    +1
    Unlike
  • Dougie:
    @sde, hi everybody I'm getting a tiger salamander coming from Katy Texas what are the shipping conditions that's okay to have them shipped to me in the state of Vermont it's just starting to get the temperature low above 45 but it may be too hot to ship him any thoughts or ideas on how to work this out
    +1
    Unlike
  • newtmember:
    as long as its not freezing they should ship fine. I usually ship mine in 2 days priorities like axolotl. insulation and some cold pack. Is this morphed or still a larvae?
    +1
    Unlike
  • macmac194:
    Greetings I have a quaratined tiger salamander due to not feeding and feeling lethargic. I saw a slimy green stuff inside the enclosure. Is this vomit? Poop?
    +1
    Unlike
  • Jjrio421:
    Are you still looking to rehome any of your axolotl babies?
    +1
    Unlike
  • Chat Bot:
    Guest nagato has joined the room.
  • (Guest) nagato:
    Does anybody know where or who to buy danube crested newts from?
  • Mother of Dragons:
    Anyone in the DMV area looking for juvenile axolotls? I have several morphs available. Experienced owners and pickup only please.
    +1
    Unlike
  • Chat Bot:
    Guest axmaolotl has joined the room.
  • Ariania Lee-Ann:
    I currently have a 3 year old axolotl, he hasn't been eating for the past couple of weeks and has lost a lot of weight. Hedwig usually eats bloodworms and earthworms just fine but now he won't even stud it. I've done a water change to make his nitrate lower and his water is at a good temperature
    +1
    Unlike
  • Chat Bot:
    Guest zippy has joined the room.
  • (Guest) zippy:
    what substrate is he on?
  • Linkisnotzelda:
    Are any of you guys on Quora? I’ve started an axolotl space there and am looking for people interested in helping out!
    +1
    Unlike
  • KarateKid08:
    I am wanting a spotted or tiger salamander and I was wondering how often to feed, what the best feeders would be and how many fed per feeding session.
    +1
    Unlike
  • Chat Bot:
    KarateKid08 has left the room.
    +1
    Unlike
  • Chat Bot:
    KarateKid08 has joined the room.
    +1
    Unlike
  • newtboi:
    Can I has alpine newts pls
    +1
    Unlike
  • ndbug:
    Any ambystoma breeders looking for californiense
    +1
    Unlike
  • axolotl owner2020:
    does anybody have any information on homemade baby axolotl food?
    +1
    Unlike
  • axolotl owner2020:
    I have an earthworm farm, and a tight budget.
    +1
    Unlike
  • Naxuzi:
    Hey guys I was wondering if my axolotl looks fine to you he/she (still don’t know) I’d activate and eating as usual but I did notice veins in the tail area.. let me know what you guys think! Also if anyone could tell if it’s a boy or girl that would be great! (Zolo was eating a worm and pretty sure the worm pooped XD)
    +2
    Unlike
  • Dougie:
    Where can I find a yellow western tiger
    +1
    Unlike
  • Chat Bot:
    Eleven11 has left the room.
    +1
    Unlike
  • Chat Bot:
    Eleven11 has joined the room.
    +1
    Unlike
  • Chat Bot:
    Eleven11 has left the room.
    +1
    Unlike
    Chat Bot: Eleven11 has left the room. +1
    Top