diff --git a/booking/models.py b/booking/models.py
index 8a770c4..4f6aa6d 100644
--- a/booking/models.py
+++ b/booking/models.py
@@ -107,3 +107,7 @@ class Booking(models.Model):
     @staticmethod
     def total_booking_time():
         return Booking.objects.filter(start_ts__isnull = False, end_ts__isnull = False).extra(select = {'amount': 'sum(strftime(%s, end_ts) - strftime(%s, start_ts))'}, select_params = ('%s', '%s'))[0].amount
+
+    @staticmethod
+    def duck_booking_time(duck):
+        return Booking.objects.filter(start_ts__isnull = False, end_ts__isnull = False, duck = duck).extra(select = {'amount': 'sum(strftime(%s, end_ts) - strftime(%s, start_ts))'}, select_params = ('%s', '%s'))[0].amount
diff --git a/booking/tests.py b/booking/tests.py
index dda1e70..968c351 100644
--- a/booking/tests.py
+++ b/booking/tests.py
@@ -184,3 +184,7 @@ class BookingTimeTest(TestCase):
 
     def test_total_booking_time(self):
         self.assertEqual(Booking.total_booking_time(), 259200)
+
+    def test_duck_booking_time(self):
+        self.assertEqual(Booking.duck_booking_time(self.duck1), 86400)
+        self.assertEqual(Booking.duck_booking_time(self.duck2), 172800)