mike williams's picture

Found beside the River Arrow

Observed: 13th January 2013 By: mike williams
Found beside the River Arrow
Description:

We found what look like black fish eggs on the bank of the River Arrow in North Herefordshire. Beside it lie what look like entrails.

Identifications
Species interactions

No interactions present.

Comments

dejayM's picture

Another ovarian/avian/Anura/mystery

I think before the month is out there will be even more!!
There is quality and informed debate here
http://www.ispot.org.uk/node/316960
and here
http://www.ispot.org.uk/node/316939
I have agreed with Chrisbrooks but put it in Amphibians & Reptiles Mike (if you can).
Good picture, good stuff!
Derek

nightfly's picture

Another good observation of

Another good observation of ova+oviduct being left uneaten. Similar to this :

http://www.ispot.org.uk/node/312356?nav=related

This linked one is definitely frog as there are no toads in NE Ireland. The above observation looks good for frog but following yesterdays discussion (http://www.ispot.org.uk/node/316960?nav=latest) I am relunctant to agree frog as I have no way of knowing for sure this didnt come from a toad.

Good observation, the story goes on!

Cathal.

nightfly's picture

Chris, I'd suggest there's a

Chris,
I'd suggest there's a high likelihood this came from a frog going by its appearance and personal familiarity with the same stuff but I know zero about toads, their habitat, habits, abundance etc. Just dont know anything about them, especially if their ova and oviduct are indistinguishable from that of a frog and are similarly left uneaten by predators.

Cathal.

chrisbrooks's picture

Frogs toads

Hi Cathal, I understand what you are saying but I'm saying "it might be this" which on the balance of probabilities is likely. Regards Chris.

nightfly's picture

This brings us to a good

This brings us to a good point Chris as I too used 'its likely to be this but I cant be certain' for star jelly because it was likely to belong to a frog but I couldnt be certain. But in agreeing an ID are you agreeing the ID or the confidence level in the ID????? Thats the thing, I understood that if I agreed common frog then I was in firm agreement that it was common frog and wasnt agreeing that it might be common frog. I'd like to agree it as I think you're right I just cant eliminate the possibility of toad.

Edit- I do realise that the answer to the above is quite obvious, you agree if you feel strongly it is correct, not if you think theres a bit of a chance. Having observed the same thing before here where there are only frogs to pick from I think I feel strongly enough that this is frog! Sorry for the thinking out loud exercise!!

Cathal.

dejayM's picture

No help!

I don't think this will help but I'm going to try -
"Common toads secrete an irritant from their skin that prevents most predators from wanting to eat them". http://www.bbc.co.uk/nature/life/Common_Toad
"As a defence mechanism the common toad can excrete toxins through its gladular skin if attacked by a predator" - The Surrey amphibian and reptile group (Web)
"The skin of one toad contains enough toxin to cause serious symptoms or even death in animals and man" - http://www.textfiles.com/drugs/toadtoxins.drg

It is possible that I have breached copyright by reproducing this below but it is taken from the Internet
It is a tiny passage from Predation of Breeding Western Toads by Deanna H Olson
Copeia © 1989 American Society of Ichthyologists and Herpetologists (ASIH)
"Predation by ravens (Corvus corax) on western toads (Bufo boreas) was observed at three of 15 toad explosive breeding aggregations. At one aggregation, over 20% of the toad annual breeding population was killed and found eviscerated near the communal breeding site. Predation was observed when toads were breeding in shallow water, 5-25 cm deep, but not when toads remained in deeper water."
............
So a few points for the Know-Team to consider.
I have always thought that toads were pretty poisonous to predators (Ravens are pretty clever though - like meerkats vs scorpions)
Derek
(the debate progresses here, of course)
http://www.ispot.org.uk/node/316960