Discoloration

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Chris Smith
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Discoloration

Post by Chris Smith »

Hello all,

A colleague sent me these photos. I will leave my thoughts to myself for now (don't want to bias the discussion). I am interested to know if anyone has observed similar discolorations between the eyes, and if there are any ideas about cause.

Image

Image

Image


Thanks!
Chris

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Daryl Eby
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Re: Discoloration

Post by Daryl Eby »

I blame a misbehaving rabbit.

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axeman2729
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Re: Discoloration

Post by axeman2729 »

could be a fungus or just age

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Chris Smith
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Re: Discoloration

Post by Chris Smith »

I'm told it is localized to a single wetland (so far).

-Chris

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Daryl Eby
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Re: Discoloration

Post by Daryl Eby »

Chris Smith wrote:I'm told it is localized to a single wetland (so far).
This seems to support my violent bunny hypothesis.

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Rich in Reptiles
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Re: Discoloration

Post by Rich in Reptiles »

That is very interesting. I would love to know what it is! I agree that it could be a disease or fungus. What makes it even more interesting is that it is localized. I really doubt that it's age, the fact that it is in different species makes it even more unlikely and strange. Appears to be just dermal, but why between the eyes???

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axeman2729
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Re: Discoloration

Post by axeman2729 »

Rich in Reptiles wrote:Appears to be just dermal, but why between the eyes???
its probably a fungus kind of like the white nose syndrome in bats

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Chris Smith
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Re: Discoloration

Post by Chris Smith »

A bit more info. and my hypothesis...

All of these frogs were trapped using minnow traps as part of a research project. I suspect this discoloration is the result of injury (trauma caused by jumping around within the trap). However, they are not seeing this discoloration at all ponds being sampled in this way... yet.

Disease / pathogens are a plausible hypothesis and I suspect they may consider testing (I will be sure to keep everyone in the loop).

-Chris

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Daryl Eby
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Re: Discoloration

Post by Daryl Eby »

Chris Smith wrote:I suspect this discoloration is the result of injury
Looks like something has been hopping through the forest and bopping them on the head.

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Kelly Mc
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Re: Discoloration

Post by Kelly Mc »

when frogs are morbidly stressed or injured they will exude a tacky exudate from the skin. If the frogs are sticky with it it is distinctive from a normal slime. A tacky frog with a darkened bruise like area would strongly speak to trauma to me to. repeated jumping against the anterior of the trap as up and out is the way they propel themselves. Perhaps the manner or circumstances that the traps of the these frogs were placed or managed incited more panic then the traps in the other ponds

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Kelly Mc
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Re: Discoloration

Post by Kelly Mc »

These pics are great illustration of how frogs protect their large and vulnerable eyes in the seconds they project themselves shooting through cover or cutting through the water muscles pull the eyes into the sockets the supraorbital features are compressed exposing only the bony plane to the impact of obstruction. when dormant or dry it is same. must protect those peepers and keep them lubricated and unscathed if your Natures Candy. perhaps even some aerodynamic advantage of lessening drag plays a part as well. as seen in some sleekening morphologies and stereotypical actions of other prey animals that flee with velocity

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Kelly Mc
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Re: Discoloration

Post by Kelly Mc »

The third pic especially looks like chromophore reaction.

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Chris Smith
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Re: Discoloration

Post by Chris Smith »

Thanks for the suggestions all. A few other colleagues are leaning toward aggregations of melanophores / chromatophores (with several potential causes).


-Chris

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Kelly Mc
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Re: Discoloration

Post by Kelly Mc »

Yes this was interesting :) perhaps melanophores produced from floating in closed space in unescapable sun? The longer i looked at the pics the more it looks like pigmentation. This was really neat to think about

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Daryl Eby
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Re: Discoloration

Post by Daryl Eby »

Did the discoloration persist? Or was it hare today goon tomorrow?

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Chris Smith
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Re: Discoloration

Post by Chris Smith »

Daryl Eby wrote:Did the discoloration persist? Or was it hare today goon tomorrow?
They were released (per sampling design).

-Chris

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BillMcGighan
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Re: Discoloration

Post by BillMcGighan »

For what it's worth.

This is the same Upland Chorus Frog, 4 minutes apart.

First on road.

2nd jumped into leaves on shoulder and rested for 4 min.
Attachments
FUC (2).jpg
FUC (1).jpg

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Chris Smith
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Re: Discoloration

Post by Chris Smith »

BillMcGighan wrote:For what it's worth.

This is the same Upland Chorus Frog, 4 minutes apart.

First on road.

2nd jumped into leaves on shoulder and rested for 4 min.



Image

Image

Awesome, thanks!

-Chris

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