diff --git a/conda/compass_env/load_compass.template b/conda/compass_env/load_compass.template
index 1b1a7242aa..15513a6631 100644
--- a/conda/compass_env/load_compass.template
+++ b/conda/compass_env/load_compass.template
@@ -1,6 +1,7 @@
 echo Loading conda environment
 source {{ conda_base }}/etc/profile.d/conda.sh
-conda activate {{ compass_env }}
+source {{ conda_base }}/etc/profile.d/mamba.sh
+mamba activate {{ compass_env }}
 echo Done.
 echo
 
@@ -8,4 +9,4 @@ echo
 
 {{ spack }}
 
-{{ env_vars }}
\ No newline at end of file
+{{ env_vars }}