--- a/net/minecraft/world/item/MobBucketItem.java
+++ b/net/minecraft/world/item/MobBucketItem.java
@@ -18,6 +18,10 @@
 import net.minecraft.world.level.gameevent.GameEvent;
 import net.minecraft.world.level.material.FluidType;
 
+// CraftBukkit start
+import org.bukkit.event.entity.CreatureSpawnEvent;
+// CraftBukkit end
+
 public class MobBucketItem extends ItemBucket {
 
     private final EntityTypes<? extends EntityInsentient> type;
@@ -54,7 +58,7 @@
         }
 
         if (entityinsentient != null) {
-            worldserver.addFreshEntityWithPassengers(entityinsentient);
+            worldserver.addFreshEntityWithPassengers(entityinsentient, CreatureSpawnEvent.SpawnReason.BUCKET); // CraftBukkit
             entityinsentient.playAmbientSound();
         }