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Blind eyed frog for Neels

Blind eyed frog for Neels
Photo Information
Copyright: Anna Eksteen (Miss_Piggy) Gold Star Critiquer/Gold Note Writer [C: 2285 W: 5 N: 5300] (18714)
Genre: Animals
Medium: Color
Date Taken: 2011-03-27
Categories: Amphibians
Camera: Sony Cybershot DSC H9, Carl Zeiss Vario-Tessar 15x Optical zoom, Digital ISO 400
Exposure: f/2.8, 1/25 seconds
More Photo Info: [view]
Photo Version: Original Version
Theme(s): Frogs and Toads, RARE or SIGNIFICANT contributions to TN 1, Dedications I have made, Bayram's Favourites-III, Animals from my garden, Nature's Oddities [view contributor(s)]
Date Submitted: 2011-04-14 14:40
Viewed: 5300
Points: 74
[Note Guidelines] Photographer's Note
Natal Tree Frog / Leptopelis natalensis

Today's image of a blind eyed Tree Frog I would like to dedicate to Neels Gunter (corjan3). I have learned such a lot from his valuable contributions since he has joined Trek Nature, especially the images with a Geological tendency.

When I saw this frog, I was quite excited as the thought of a reptile or amphibian having a cataract on its eye, never entered my mind until I saw it for myself. I came to realise that it is just not something one would think about. How amazing and surprising can nature be?

I wanted to share this image so badly, but trying to get information in this regard was almost fruitless. Eventually I contacted numerous Zoology departments of various South African universities and I was advised to contact Prof. Angelo Lambiris. How grateful I was when he responded to my e-mail and gave me a very detailed explanation, not only of the condition of the frog's eye but he also shared a bit about his profession. I found it very interesting and therefore I share the contents of the mail with you, as I received it.

Explanation by Prof Angelo Lambiris
This is an adult Natal Tree Frog, Leptopelis natalensis, first described by Andrew Smith in 1849. With regard to the frog's left eye, it is difficult to be sure what is actually happening on the basis of one photograph. The pupils are quite widely dilated, and it is possible that light is entering a perfectly normal left eye at one particular angle, causing what is called the "retinal reflex" light is bounced off the retina and back through the lens to give the kind of appearance shown in your photograph. If so, then it is purely a matter of chance that it happened, and is of no clinical significance. Indeed, when one looks into an eye through an ophthalmoscope, one tries to elicit the retinal reflex as part of the clinical examination.

On the other hand, it could well be a cataract, and I am inclined to think that is indeed one, for two reasons. Firstly, the normal retinal reflex has a more translucent quality than is apparent in the photograph; and secondly, the left pupil is distinctly more dilated than the right pupil. This would strongly suggest that less light is reaching the left retina than is reaching the right one, and unless there is an injury to the nerve supplying the iris, the most likely cause would be an opaque lens in other words, a cataract. I have only seen cataracts in a few reptiles, in the course of some forty years of herpetological medicine, and none that I can remember in any amphibian. This is a most interesting frog, and the more I look at it, the more certain I am that it is a cataract. It would be unwise to speculate on the cause of the cataract without actually examining the frog itself very carefully.

I have operated for cataract on a few lizards, in all cases with very good results. There is no technical reason that I am aware of why such an operation should not be possible on a frog, but I don't know of it having been done before. In my quite extensive experience of eye disorders in reptiles, I have found that they invariably compensate very well indeed to partial or complete loss of vision in one eye, not only in finding and capturing food, but also in various activities such as climbing, which normally depend on stereoscopic vision. I do not think that a cataract would seriously impair a frog's ability to catch food, and if the loss of vision was gradual (as it almost certainly would have been) then it would easily have adjusted to clear vision in one eye only.

These frogs are pretty territorial, and tend to stay in one place for a long time though of course they do move around a lot, and you cannot be sure of finding any given individual in one particular spot at any one time. In one study, which included Leptopelis, I found that marked frogs kept to their territories for year after year; and some frogs would come back to exactly the same spot for years when mating and laying eggs, and would return even when taken as far as 2.5 km away from their home ranges.

You may well be able to keep a track of this frog and see what happens to its eye. Should you ever feel that the eye is deteriorating badly enough to require surgery, please let me know and I would be glad to do it for you. I do in fact have a clinic specifically for reptiles and amphibians, with a fully equipped operating theatre, and all my work on wild animals is pro bono, so you would not have to worry about costs.

I hope that these rather hasty notes will, brief thought they are, give you enough information for your needs.

With best wishes

Unfortunately I have not seen the frog again and therefore it would not be possible to monitor it as the kind Professor suggested. He also gave me rather interesting information about the frog itself which I will keep and share with you at a later stage.

I hope you enjoyed looking at this photo as much as I took pleasure in taking it.

flashpoint, maaciejka, maurydv, PaulLees, bungbing, KOMSIS, Ilducabianco, paolo49, foozi, lousat, PeterZ, corjan3, anel, brech, CeltickRanger, jaycee, Dis. Ac., samiran88, vanni2009, Ingrid1 has marked this note useful
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Critiques [Translate]

  • Great 
  • manyee Gold Star Critiquer/Gold Star Workshop Editor/Gold Note Writer [C: 3089 W: 230 N: 6774] (23770)
  • [2011-04-14 17:05]

Hi Anna,
What a fascinating subject... and an equally fascinating note.
Thank you for going through all the trouble to solve the mystery, and thank you to Prof. Lambiris for such a detailed explanation.
I love the colors on his right iris. It looks like a precious gem.
The colors and texture on the skin are amazing as well. A pink toad?
TFS. : )

  • Great 
  • ana974 Gold Star Critiquer/Silver Workshop Editor/Gold Note Writer [C: 477 W: 48 N: 968] (4857)
  • [2011-04-14 20:50]

Hello Anna !
Good post and nice dedication to Neels.I liked the instructive explanations in your note, really the Nature is amazing !TFS
Here in my country is almost 1:00h am ! So...good nigth and hope you keep posting.
Regards from,

Very interesting note Anna! The photo is also interesting and beautiful.

Hi Anna,
really incredible photo! Perfect point of view and sharpness. Excellent composition. Very good depth of field and perspective.
Thanks for sharing,

Ciao Anna, wonderful portrait of amazinmg creature wiyth incredible eyes, fantastic colors, fine details and splendid sharpness, very well done my friend, ciao Silvio

Hallo Anna,
a very beautiful portrait of this Tree Frog, very interesting notes too; very good sharpness and spendid natural colours, excellent point of view with a great wide-angle perspective, very nice composition
Best regards

Hi Anna,

A very nice thoughtful and well deserved dedication to Neels,

Fascinating image and information of the Natal Tree Frog, great exposure under the harsh conditions, sharp around the head area, with a strong composition,
Congratulations Anna and well done,


Hello Anna,
Very interesting frog with good sharpness, details, point of view and colours of the frog is fantastic,
Thanks for sharing,

Lovely macro concentrating on the eye!

Hallo Anna,
and the ugly frog:)
Many looks cute. Great colours, good details and composition. Superb POV and nice DOF.
Best wishes,

Hi Anna,
Fantastic macro for this lovely little frog.
Colours and composition are excellent.
Thanks for sharing

Hello Anna, beautiful image of this strange frog, an excellent result with a really nice person. All the best, Paul

  • Great 
  • foozi Gold Star Critiquer/Gold Note Writer [C: 2791 W: 0 N: 6696] (25839)
  • [2011-04-15 3:53]

Hello Anna,
how professional youre and how patient youre before posting this shot. The hardwork and dilligent for this shot reflected in all other posts by you.
The frog is definitely interesting and the knowledge and information from your notes are definitely enlightening.
thanks for sharing this unique and special image along with a superb note.


  • Great 
  • nagraj Gold Star Critiquer/Gold Star Workshop Editor/Gold Note Writer [C: 1618 W: 106 N: 3208] (15166)
  • [2011-04-15 6:04]

Very interesting viewpoint and colorful frog image. tfs.

  • Great 
  • lousat Gold Star Critiquer/Gold Star Workshop Editor/Gold Note Writer [C: 6595 W: 89 N: 15659] (65489)
  • [2011-04-15 7:39]

Hi Anna.How is strange this frog,you are lucky to live in a fanatstic paradise full os strange species! And how is great the choice of point of view to show us the best of this incredible specie.Very impressive quality as usual whit the best sharpness and magnificent colors.Thanks for share,have a nice weekend,Luciano

Very beautiful portrait!

  • Great 
  • PeterZ Gold Star Critiquer/Gold Star Workshop Editor/Gold Note Writer [C: 5137 W: 166 N: 13121] (49139)
  • [2011-04-15 9:10]

Hello Anna,
What a special photo! Not only because of the species of frog, but also because of the story with the blind eye. A photo in splendid colours and very good sharpness. Taken from a very good frontal POV. Good depth of field. A really perfect note!

hello Anna
very good sharpness picture of this beauty frog
great details and lovely colours
greeting lou

Anna wonderful image and your photo performance!
Regards Nasos

Hello Anna,
I am truly honoured and humbled and overwhelmed by your very kind gesture. This is an excellent and a very extraordinary photo and, for me, for more than one reason. Congratulations to both you and the professor on this very informative note and for the trouble you took. It is much appreciated.

Please forgive me for the personal note of what follows. I could not believe it when I saw this image because I would have been completely blind by now had it not been for the magnificence of science and its multitude of practical manifestations, eye surgery in this case. Amongst many other very serious consequences for me would have been that I would not have been able to enjoy the beauty of this wonderful site and its members. And without sight I would not have been able to still enjoy one of my special preferences - mineral optics and microscopy. May we please also dedicate this fabulous image to basic and applied scientfic research in all its forms.

Ciao Anna. Impressive portrait in good quality and brilliant colours.


  • Great 
  • anel Gold Star Critiquer/Gold Note Writer [C: 3053 W: 3 N: 8715] (40574)
  • [2011-04-16 5:09]

Hello Anna,
This is really a special shot. Amazing impression to look in the eyes of this partially blind frog. Interesting note too which you received by e-mail by a very helpful Professor. You also have chosen an ideal point of view to show the differences of both eyes.
Have a nice weekend
Kind regards

  • Great 
  • tuslaw Gold Star Critiquer/Gold Star Workshop Editor/Gold Note Writer [C: 2754 W: 282 N: 4931] (19883)
  • [2011-04-16 12:01]

Hello Anna,
What a neat image and wonderful story behind it!!! Who would has guessed that frogs could develope cataracts, and even more amazing the fact that someone could actually operate on them to remove it.
I definitely believe you deserve an A+ for your effort to find out information on this tiny little frog and his unique condition.
Extremely interesting image and shown with clarity and a very interesting story!!!

  • Great 
  • egres Silver Star Critiquer/Gold Note Writer [C: 44 W: 2 N: 144] (754)
  • [2011-04-16 16:05]

Hello Anna
Good photo of a rare frog. Lots of sharp details and colors. Nice closeup of the head and very instructional note



Hello Anna

Great close-up photo of this frog, with fine
frontal POV giving that expressive great
eye-contact and glance with you, beautiful light,
excellent focus sharpness and details, TFS


  • Great 
  • siggi Gold Star Critiquer/Gold Star Workshop Editor/Gold Note Writer [C: 3097 W: 109 N: 12399] (52850)
  • [2011-04-17 12:31]

Hello Anna.
Excellent capture of this Tree frog with great pose and composition, sharp details,very good colours.Best regards Siggi

Hi MF Anna,

This is really great presentation indicating your real nature interest. Perfectly captured from great POV with wonderful DOF! BTW i also learned so much things about this situation.
TFS and have a great new week!
Warm regards,


  • Great 
  • jaycee Gold Star Critiquer/Silver Workshop Editor/Gold Note Writer [C: 2454 W: 10 N: 8044] (25460)
  • [2011-04-18 16:54]

Hi Anna,

A fascinating picture and most interesting notes. I'm so glad you were able to get so much information to share with us. I never really thought about cataracts in species other than humans. Excellent shot of this frog with perfect views of both eyes. Love the composition on the leaf.


Hello Anna,

Nice dedication to Neels.
Great pov and exellent dof and sharpness.
Fine colors.Interesting shot with the eyes.


Hi Anna,
incredible picture, fantastic macro. Looks as if the frog had to different eyes!
congratulation for this shot.

A fascinating note, with a marvelous capture of this blind eyed tree Frog. Nice colour and sharpness.

hello Anna,
congratulations for the excellent photo, excellent POV, sharpness and color.
Thanks for sharing and Happy Easter
Hello Vanni

Hi Anna,
Nice close up of the natal tree frog. This is one that I have not seen, it
looks very similiar to it's cousin the peacock or globed-eye tree frog (leptopelis vermiculatus). I have personally seen cataracts if amphibians eyes and the condition is very similiar. I would agree especially seeing the degree of the pupil's dialation.

Un trabajo diferente y de gran originalidad.
Saludos Anna.

  • Great 
  • Argus Gold Star Critiquer/Gold Star Workshop Editor/Gold Note Writer [C: 5038 W: 260 N: 15594] (50626)
  • [2011-05-21 12:19]

Hello Anna,
A missed this interesting capture.
The Natal Tree Frog is an interesting and attractive species, presumably seen for the first time on TN.
The eye condition is interesting too and well researched by your contact with the professor.
The frog' head, showing the affected eye is well presented from this frontal POV with fine sharpness and colours against a suitable leaf BG, all of which makes this a fine contribution to TN and one that I'm sorry to have missed before.
Thanks and enjoy the rest of your weekend,

Hi Anna,
Its a great macro of this frog. It has a scary look and you caught it in an excellent way! And i Must say that you done your research more than very well!
Best Regards!

Goodness me, my dear friend, this makes be really feel bad ! I always thought the worst I had seen was an ostrich with a fat orange tick on his eye...

Thanks so much for adding your image with the really interesting information to my theme" Nature's oddities"

I must compliment you on your determination to dig up this info as well as your incredible filing system to find this photo!

Take care and thanks for sharing your work,
Hugs Ingrid

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