Discoloration

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Chris Smith
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Discoloration

Post by Chris Smith » January 11th, 2013, 11:43 am

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 » January 11th, 2013, 12:33 pm

I blame a misbehaving rabbit.

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axeman2729
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Re: Discoloration

Post by axeman2729 » January 11th, 2013, 4:37 pm

could be a fungus or just age

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Chris Smith
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Re: Discoloration

Post by Chris Smith » January 12th, 2013, 9:20 am

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 » January 12th, 2013, 9:57 am

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 » January 12th, 2013, 11:50 am

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 » January 12th, 2013, 1:11 pm

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 » January 12th, 2013, 2:13 pm

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 » January 12th, 2013, 8:36 pm

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 » January 12th, 2013, 9:27 pm

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 » January 14th, 2013, 12:48 am

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 » January 15th, 2013, 5:29 pm

The third pic especially looks like chromophore reaction.

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Chris Smith
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Re: Discoloration

Post by Chris Smith » January 15th, 2013, 5:42 pm

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 » January 15th, 2013, 6:16 pm

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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Re: Discoloration

Post by Daryl Eby » January 15th, 2013, 6:27 pm

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 » January 15th, 2013, 6:46 pm

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 » January 15th, 2013, 7:26 pm

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 » January 16th, 2013, 6:11 pm

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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