diff --git a/src/tape/ensemble.py b/src/tape/ensemble.py
index 9ef50499..e642263a 100644
--- a/src/tape/ensemble.py
+++ b/src/tape/ensemble.py
@@ -1870,10 +1870,8 @@ def select_random_timeseries(self, seed=None):
         in larger partitions.
 
         """
-        if seed is not None:
-            rng = np.random.default_rng(seed)
-        else:
-            rng = np.random
+
+        rng = np.random.default_rng(seed)
 
         # We will select one partition at random to select an object from
         partitions = np.array(range(self.object.npartitions))