diff --git a/api/test/unit/serializers/test_media_serializers.py b/api/test/unit/serializers/test_media_serializers.py
index 3b854980c73..ea2500a2681 100644
--- a/api/test/unit/serializers/test_media_serializers.py
+++ b/api/test/unit/serializers/test_media_serializers.py
@@ -99,6 +99,27 @@ def test_media_serializer_adds_license_url_if_missing(
     assert repr["license_url"] == "https://creativecommons.org/publicdomain/zero/1.0/"
 
 
+def test_media_serializer_logs_when_invalid_or_duplicate_source(media_type_config):
+    sources = {
+        "image": ("flickr,flickr,invalid", "flickr"),
+        "audio": ("freesound,freesound,invalid", "freesound"),
+    }
+    with patch("api.serializers.media_serializers.logger.warning") as mock_logger:
+        serializer_class = media_type_config.search_request_serializer(
+            context={"media_type": media_type_config.media_type},
+            data={"source": sources[media_type_config.media_type][0]},
+        )
+        assert serializer_class.is_valid()
+        assert (
+            serializer_class.validated_data["source"]
+            == sources[media_type_config.media_type][1]
+        )
+        mock_logger.assert_called_with(
+            f"Invalid sources in search query: {{'invalid'}}; "
+            f"sources query: '{sources[media_type_config.media_type][0]}'"
+        )
+
+
 @pytest.mark.parametrize(
     "has_sensitive_text",
     (True, False),