Brown-throated Three-toed Sloth
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Brown-throated Three-toed Sloth Bradypus variegatus
The closest (so far!) I've ever been to a sloth. This gentlemen seemed quite content to hang and scratch.

We saw only one sloth in our entire 14 days in northeast Brazil. Since their biggest predator (harpy eagles) are now few and far between, I had to ask our guide Ciro Albano why there wasn't a sloth population explosion. No ideas... So I had to google how sloths "mate".

Apparently sloths are like cats. When the female is in esterus, she lets out a scream saying "Hey Honey" that is sent far and wide. Then of course the male sloths come running, running being a relative term...since the fastest sloths can go is 600 feet a day. So I can only imagine how long it takes for males to come a running. The actual act lasts less than a minute. Pretty quick by sloth terms. Average life span for a sloth is 20 to 40 years in the wild, so mating being "difficult" kind of makes sense in terms of population growth.
Focal length: 500 mm fStop: 8 ISO: 400 Shutter Speed: 1/640 sec.
Porto Segura, Bahia, Brazil - Verasel Reserve
Dec 7, 2011