diff --git a/src/agora/io/signal.py b/src/agora/io/signal.py
index f77909527a6392386a1f84994d87e925c73fed59..e97e2dc3d2acfb09afddaeb0419a66b4188df5b6 100644
--- a/src/agora/io/signal.py
+++ b/src/agora/io/signal.py
@@ -218,7 +218,7 @@ class Signal(BridgeH5):
 
     @property
     def n_merges(self):
-        print("{} merge events".format(len(self.merges)))
+        return len(self.merges)
 
     @property
     def picks(self):