Jump to content
UltravioletPhotography

White-Nose Syndrome in Bats


Recommended Posts

I thought this article was quite interesting and a fabulous use of UVIFL, something I found setting up some new Google alerts just now. An excerpt:

 

"WNS cannot be reliably identified with visual inspection and the only way to confirm presence of disease has been to euthanize the bats and send them to a laboratory for testing. In an effort to evaluate UV light as a non-fatal WNS screening method, 168 bats submitted for diagnostic testing from 2009 through spring 2012 had their wings examined with both UV light and microscopically to determine if they had WNS. Comparing the results of histology and UV light showed that 98.8-percent of bats with orange-yellow wing fluorescence (80) under UV light were confirmed positive for WNS microscopically, and 100-percent of the 88 bats that were fluorescent negative were also microscopically negative."

 

It'd be interesting to speculate why orange-yellow wing fluorescence is diagnostic, as in what does orange-yellow wing fluorescence represent, and at what nm frequencies. Is anyone aware of a list of colour and (?)mineral/cause ?

Link to comment

Very interesting ! Thanks for this find, Johan.

 

Many fungi fluoresce, both large and microscopic in size. For example, athelete's foot fungus (tinea) fluoresces under UV. So it isn't surprising that this bat fungus also fluoresces.

 

This paper was very good about listing the equipment used to photograph the fluorescence:

  • D80 (used in darkened room, f3.3 for 8" @ ISO-200).
    • with 60mm AF lens with no filter.

    [*]51-LED 385 nm UV flashlight #7202 from LED Wholesalers for initial diagnosis.

    [*]Blak-Ray UVL-56 for the photography.

    [*]Other field work done using

    • 9-watt 368 nm fluorescent light WTC 9L-110 from Way Too Cool at Fluorescents.com.
    • Canon EOS 350D (f/5-f/10 for 1/2-30" @ ISO-200)
      • with EFS 18-55 mm or EF 100 mm lens with 58mm UV filter (unspecified)

      [*]Nikon D300 (f/5.3-f/5.8 for .15-.4" @ ISO-1000)

      • with Nikkor 28-80 mm AF lens

****************

 

Because their method has proved diagnostic for the bat fungus disease, we will not ding the experimenters for sometimes failing to use a barrier filter on their lens or for failing to provide additional excitation filtration. Capturing stray light leaks seems not to matter in this experiment. FWIW, typical 385 nm UV-LEDs put put quite a bit of visible blue.

 

Poor bats!! I hope this disease can be stopped somehow.

Link to comment

Because their method has proved diagnostic for the bat fungus disease, we will not ding the experimenters for sometimes failing to use a barrier filter on their lens or for failing to provide additional excitation filtration. Capturing stray light leaks seems not to matter in this experiment. FWIW, typical 385 nm UV-LEDs put put quite a bit of visible blue.

 

Andrea, this is a simple "positive vs. negative" test, and not quantitative analysis. If fluorescence is strong enough to be visually separated from reflected "leak" from LED, or of totally different clour, there is no need for barrier filters. Have you seen anyone using additional barrier filters when examining documents or currency?

Link to comment

That was exactly my point !! Their method worked so barrier/excitation filters were not needed.

 

However, there may come a time when differential diagnoses might need to be made and those filters would be required. Presumably they are savvy enough to realize this given that not all fungi fluoresce the same colours.

 

I've never seen actually seen anyone examining documents or currency. :D Although we do have Johan's posts with currency subjects which were quite interesting.

Link to comment

I've never seen actually seen anyone examining documents or currency.

 

 

You never took a plane? (security checks drivers licenses with UV LED at all entries to TSA check points)

Link to comment
Presumably they are savvy enough to realize this given that not all fungi fluoresce the same colours.

 

Strikes me that the issue is complex. As in not only do all fungi fluoresce in different colours, but the excitation frequencies of lights are different spectra too, so themselves will also give a different result. I should imagine that ultimately to use this as a repeatable tool for emperical science you'd need to be very specific about excitation frequency, emission frequency permitted, and various other factors that seem to influence UVIFR output. I think it's very interesting avenue of research, what the UVIFL colours mean, why each colour is there, the minerals/chemicals/biological processes involved. Wish there was more data on it. And ultimately wouldn't it be lovely if there was a lighting device that you could tune to a specific NM and spectrum and use it for photography. One can dream.

Link to comment

And ultimately wouldn't it be lovely if there was a lighting device that you could tune to a specific NM and spectrum and use it for photography. One can dream.

 

Indeed.....

Link to comment

Please sign in to comment

You will be able to leave a comment after signing in



Sign In Now
×
×
  • Create New...