diff --git a/rollbar/lib/transforms/shortener.py b/rollbar/lib/transforms/shortener.py
index 227dae34..ff83738e 100644
--- a/rollbar/lib/transforms/shortener.py
+++ b/rollbar/lib/transforms/shortener.py
@@ -105,6 +105,8 @@ def _shorten(self, val):
 
         if isinstance(val, sequence_types):
             val = self._shorten_sequence(val, max_size)
+            if isinstance(val, string_types):
+                return val
             return self.traverse_obj(val)
 
         if isinstance(val, number_types):