Missouri Master Naturalists- Springfield Plateau Chapter

Friday, January 8, 2016

Carnivorous Turtle

Lepidopteran Lunch - Brian Edmond

Brian Edmond sent me the photograph above of a three-toed box turtle munching on a butterfly.  When I saw the picture on my phone I guessed it was a Wood Satyr, based on the tan eye spots with black "pupils" on the wing.  When I brought it up on the computer later, the white spots that had looked like the gravel drive were actually wing tip spots of a Hackberry Emperor (Asterocampa_celtis).
 
Hackberry Emperor - Bob Moul
Wood Satyr - Bob Moul
Eye spots like these are common, found on several similar butterflies.  The Wood Satyr lacks the white spots on the wing tip.  Northern Pearly-eyes have a small white "pearl" in the black eye spots.  The Painted Lady has white spotted wing tips but the eye spots are much smaller and located on an orange background.



Painted Lady - Bob Moul
Northern Pearly-eye - Bob Moul














Three-toed box turtles are the official State Reptile of Missouri.  They eat insects, worms, slugs, mushrooms and green plants.  They require protein to grow so a partially carnivorous diet is important.  They have been known to eat poisonous mushrooms without harm.  In captivity they are shy about eating, pausing when observed closely.  Brian noted that the turtle stopped eating while he was photographing it, resuming when he left.  This is probably another example of "freezing" in animals sensing danger.

The Internet is a great source of information, and misinformation.  Googling "do turtles eat butterflies" brought a straightforward "NO".*  On the other hand there has been a lot on some butterflies that feed on turtles.  A report on Livescience.com describes butterflies that cover the heads of yellow-spotted river turtles in the western Amazon rain forest.  They gather there to collect the tears of turtles which contains sodium.  Butterflies require sodium that is missing in their diets.  Missouri butterflies can get minerals from moist soil, animal urine and dung, etc while the Amazon soils are very sodium depleted.

* No butterflies were injured in this blog as it was "definitely road kill" when found by the turtle