diff --git a/src/main/java/species/IdentifyPopulation.java b/src/main/java/species/IdentifyPopulation.java
index 68dea76c2ef15b90f8b5201a72be7c4b73d39ef2..f6e651d02dfa113db8ceb8b4b71d28b0a10d4960 100644
--- a/src/main/java/species/IdentifyPopulation.java
+++ b/src/main/java/species/IdentifyPopulation.java
@@ -69,7 +69,8 @@ public class IdentifyPopulation extends AquaNismsGroupProcess<DiadromousFish, Di
 					bW = new BufferedWriter(new FileWriter(new File(group.getOutputPath()+
 							fileNameOutput +group.getSimulationId()+ ".csv")));
 
-					BasinNetworkReal nbr= (BasinNetworkReal) pilot.getAquaticWorld().getEnvironment();
+					// BasinNetworkReal nbr= (BasinNetworkReal) pilot.getAquaticWorld().getEnvironment();
+					BasinNetwork nbr=  group.getEnvironment();
 					bW.write("year"+sep+"migrationBasin");
 					for (String basinName : nbr.getRiverBasinNames()){
 						bW.write(sep+basinName);