private SpeciesObservationManagerMultiThreadCache GetSpeciesObservationManager(Boolean refresh = false)
 {
     if (_speciesObservationManager.IsNull() || refresh)
     {
         _speciesObservationManager            = new SpeciesObservationManagerMultiThreadCache();
         _speciesObservationManager.DataSource = new SpeciesObservationDataSource();
     }
     return(_speciesObservationManager);
 }