My only concern with the use of these type of IR cameras on nocturnal creatures is the potential for the camera's lighting to damage the eyes of the subject.

In fact the last thing you want to be doing yourself, is looking into either an IR or UV light source .. although I suspect that the power of the IR wouldn't do all that much damage to human eyes in small doses.
On a grander scale, think of the possibility of damage that the sun can do human eyes when looking directly at it!

Remember that these nocturnal creatures will surely have much more sensitivity than human eyes will .. and why they can see in the dark in the first place.
I have no idea on where you would find out any relevant info on the subject .. and I can't see any technical info on the power level or IR wavelengths involved in that Browning IR camera's lighting setup either.


On a wild tangent! ... if you had a spare $3(and-a-bit)K you may want to look into a Sony A7s and very fast aperture lens plus an external recorder to send the video feed too.
ISO200K, and 4K video .. downsampling the video(if required) should give you pretty good video in the dark and in the more appealing visible spectrum!(if you were to make this a more long term mission that is).