diff --git a/atdb/prune.py b/atdb/prune.py
index f8e235f926f3afcc40994f4d6917836b05d98bc7..547de7d049c3c13c238f48ce46dfb02e46aac752 100644
--- a/atdb/prune.py
+++ b/atdb/prune.py
@@ -53,7 +53,7 @@ def remove_surl_locations(surls: List[str], dry_run=False) -> None:
         if not dry_run:
 
             logger.debug("removing surl %s", surl)
-            logger.debug("file stats are:", context.stat(surl))
+            logger.debug("file stats are: %s", context.stat(surl))
             context.release(surl)
         else:
             logger.info("[dry-run] removing surl %s", surl)