Index: Riskeer/DuneErosion/src/Riskeer.DuneErosion.Forms/Views/DuneErosionLocationsMapLayer.cs
===================================================================
diff -u -r7f87b1e830f2c7612a75b19326543ce03e07fa34 -rd1552205c4eedabe270bf13d4551e145ad1d69e9
--- Riskeer/DuneErosion/src/Riskeer.DuneErosion.Forms/Views/DuneErosionLocationsMapLayer.cs	(.../DuneErosionLocationsMapLayer.cs)	(revision 7f87b1e830f2c7612a75b19326543ce03e07fa34)
+++ Riskeer/DuneErosion/src/Riskeer.DuneErosion.Forms/Views/DuneErosionLocationsMapLayer.cs	(.../DuneErosionLocationsMapLayer.cs)	(revision d1552205c4eedabe270bf13d4551e145ad1d69e9)
@@ -39,6 +39,7 @@
 
         private Observer duneLocationsObserver;
         private Observer userDefinedTargetProbabilitiesListObserver;
+        private RecursiveObserver<IObservableEnumerable<DuneLocationCalculationsForTargetProbability>, DuneLocationCalculationsForTargetProbability> userDefinedTargetProbabilitiesObserver;
 
         private List<RecursiveObserver<IObservableEnumerable<DuneLocationCalculation>, DuneLocationCalculation>> calculationsForTargetProbabilityObservers;
 
@@ -81,6 +82,7 @@
             {
                 duneLocationsObserver.Dispose();
                 userDefinedTargetProbabilitiesListObserver.Dispose();
+                userDefinedTargetProbabilitiesObserver.Dispose();
 
                 DeleteTargetProbabilitiesObservers();
             }
@@ -112,6 +114,12 @@
                 Observable = failureMechanism.DuneLocationCalculationsForUserDefinedTargetProbabilities
             };
 
+            userDefinedTargetProbabilitiesObserver = new RecursiveObserver<IObservableEnumerable<DuneLocationCalculationsForTargetProbability>, DuneLocationCalculationsForTargetProbability>(
+                UpdateFeatures, tp => tp)
+            {
+                Observable = failureMechanism.DuneLocationCalculationsForUserDefinedTargetProbabilities
+            };
+
             calculationsForTargetProbabilityObservers = new List<RecursiveObserver<IObservableEnumerable<DuneLocationCalculation>, DuneLocationCalculation>>();
             CreateTargetProbabilitiesObservers();
         }
@@ -120,7 +128,8 @@
         {
             calculationsForTargetProbabilityObservers.AddRange(failureMechanism.DuneLocationCalculationsForUserDefinedTargetProbabilities
                                                                                .Select(calculationsForTargetProbability => CreateDuneLocationCalculationsObserver(
-                                                                                           calculationsForTargetProbability.DuneLocationCalculations)));
+                                                                                           calculationsForTargetProbability.DuneLocationCalculations))
+                                                                               .ToArray());
         }
 
         private RecursiveObserver<IObservableEnumerable<DuneLocationCalculation>, DuneLocationCalculation> CreateDuneLocationCalculationsObserver(
Index: Riskeer/DuneErosion/test/Riskeer.DuneErosion.Forms.Test/Views/DuneErosionLocationsMapLayerTest.cs
===================================================================
diff -u -r7f87b1e830f2c7612a75b19326543ce03e07fa34 -rd1552205c4eedabe270bf13d4551e145ad1d69e9
--- Riskeer/DuneErosion/test/Riskeer.DuneErosion.Forms.Test/Views/DuneErosionLocationsMapLayerTest.cs	(.../DuneErosionLocationsMapLayerTest.cs)	(revision 7f87b1e830f2c7612a75b19326543ce03e07fa34)
+++ Riskeer/DuneErosion/test/Riskeer.DuneErosion.Forms.Test/Views/DuneErosionLocationsMapLayerTest.cs	(.../DuneErosionLocationsMapLayerTest.cs)	(revision d1552205c4eedabe270bf13d4551e145ad1d69e9)
@@ -165,7 +165,7 @@
             targetProbability.DuneLocationCalculations.AddRange(failureMechanism.DuneLocations.Select(l => new DuneLocationCalculation(l)));
             failureMechanism.DuneLocationCalculationsForUserDefinedTargetProbabilities.Add(targetProbability);
             failureMechanism.DuneLocationCalculationsForUserDefinedTargetProbabilities.NotifyObservers();
-            
+
             mapLayer.MapData.Attach(observer);
 
             // Precondition
@@ -217,6 +217,40 @@
             mocks.VerifyAll();
         }
 
+        [Test]
+        public void GivenMapLayerWithDuneLocations_WhenUserDefinedTargetProbabilityUpdatedAndNotified_ThenMapDataUpdated()
+        {
+            // Given
+            var failureMechanism = new DuneErosionFailureMechanism();
+            failureMechanism.DuneLocationCalculationsForUserDefinedTargetProbabilities.Add(
+                new DuneLocationCalculationsForTargetProbability(0.1));
+            failureMechanism.SetDuneLocations(new[]
+            {
+                new TestDuneLocation("test1")
+            });
+
+            var mapLayer = new DuneErosionLocationsMapLayer(failureMechanism);
+
+            var mocks = new MockRepository();
+            var observer = mocks.StrictMock<IObserver>();
+            observer.Expect(o => o.UpdateObserver());
+            mocks.ReplayAll();
+
+            mapLayer.MapData.Attach(observer);
+
+            // Precondition
+            AssertDuneLocationsMapData(failureMechanism, mapLayer.MapData);
+
+            // When
+            DuneLocationCalculationsForTargetProbability targetProbability = failureMechanism.DuneLocationCalculationsForUserDefinedTargetProbabilities.First();
+            targetProbability.TargetProbability = 0.003;
+            targetProbability.NotifyObservers();
+
+            // Then
+            AssertDuneLocationsMapData(failureMechanism, mapLayer.MapData);
+            mocks.VerifyAll();
+        }
+
         private static void AssertDuneLocationsMapData(DuneErosionFailureMechanism failureMechanism,
                                                        MapData mapData)
         {