diff --git a/API.md b/API.md
index 1f68d67..86a6dc8 100644
--- a/API.md
+++ b/API.md
@@ -126,6 +126,8 @@ Default: false
 
 #### onZoomAnimationStart (func)
 
+#### onDrag ((map) => void)
+
 #### onZoomAnimationEnd (func)
 
 #### onMapTypeIdChange (func)
diff --git a/src/google_map.js b/src/google_map.js
index 0fc53a9..ab8db39 100644
--- a/src/google_map.js
+++ b/src/google_map.js
@@ -770,7 +770,7 @@ export default class GoogleMap extends Component {
 
         maps.event.addListener(map, 'drag', () => {
           this_.dragTime_ = new Date().getTime();
-          this_._onDrag();
+          this_._onDrag(map);
         });
         // user choosing satellite vs roads, etc
         maps.event.addListener(map, 'maptypeid_changed', () => {