WEBVTT 00:00:06.366 --> 00:00:09.564 Each spring, nature lovers eagerly greet the signs 00:00:09.564 --> 00:00:12.150 that winter is finally coming to an end. 00:00:12.150 --> 00:00:13.249 As the days grow warmer, 00:00:13.249 --> 00:00:15.333 the flowers and trees start to bloom, 00:00:15.333 --> 00:00:16.540 and the world comes alive 00:00:16.540 --> 00:00:18.176 with the melodious call of birds 00:00:18.176 --> 00:00:20.097 in search of a new mate. 00:00:20.097 --> 00:00:21.784 But where have these enchanting sounds 00:00:21.784 --> 00:00:23.833 been hiding all winter? 00:00:23.833 --> 00:00:26.343 For almost 200 species of song birds, 00:00:26.343 --> 00:00:27.520 their winters have been spent 00:00:27.520 --> 00:00:28.981 down in the tropical climates 00:00:28.981 --> 00:00:31.524 of Central and South America. 00:00:31.524 --> 00:00:32.963 While this may sound ideal, 00:00:32.963 --> 00:00:35.137 it involves one of the most perilous journeys 00:00:35.137 --> 00:00:38.121 known in the entire animal kingdom. 00:00:38.121 --> 00:00:40.232 This journey is called migration, 00:00:40.232 --> 00:00:41.261 and for song birds, 00:00:41.261 --> 00:00:43.120 this can involve travelling somewhere 00:00:43.120 --> 00:00:45.572 between a few hundred to almost 7,000 miles 00:00:45.572 --> 00:00:47.178 in a period of several weeks 00:00:47.178 --> 00:00:48.761 to four months. 00:00:48.761 --> 00:00:50.037 Birds spend weeks preparing 00:00:50.037 --> 00:00:51.367 for the intense journey 00:00:51.367 --> 00:00:53.350 by gorging on large quantities of food, 00:00:53.350 --> 00:00:54.868 sometimes doubling their weight 00:00:54.868 --> 00:00:56.674 prior to departure. 00:00:56.674 --> 00:00:58.168 While flying, birds can lose 00:00:58.168 --> 00:01:00.867 almost one percent of their body weight an hour, 00:01:00.867 --> 00:01:04.458 so packing on the pounds is crucial to their survival. 00:01:04.458 --> 00:01:06.500 However, more than the physical stress, 00:01:06.500 --> 00:01:08.251 migrating birds are now facing 00:01:08.251 --> 00:01:09.930 a new source of hardship: 00:01:09.930 --> 00:01:11.629 landscape change. 00:01:11.629 --> 00:01:13.259 Just imagine you're the one 00:01:13.259 --> 00:01:14.768 getting ready to take a trip. 00:01:14.768 --> 00:01:15.798 You've packed the car 00:01:15.798 --> 00:01:17.430 with everything you think you need, 00:01:17.430 --> 00:01:18.347 fueled up the tank, 00:01:18.347 --> 00:01:19.637 eaten a huge breakfast, 00:01:19.637 --> 00:01:21.058 and hit the road. 00:01:21.058 --> 00:01:22.926 You've taken this journey before. 00:01:22.926 --> 00:01:24.564 You know all your favorite rest stops 00:01:24.564 --> 00:01:27.184 and little back-alley diners to grab a bite. 00:01:27.184 --> 00:01:29.098 Everything is planned out. 00:01:29.098 --> 00:01:30.903 But just as your fuel gauge starts 00:01:30.903 --> 00:01:32.236 dipping into the red zone, 00:01:32.236 --> 00:01:34.450 you pass by what should have been a gas station, 00:01:34.450 --> 00:01:36.120 except it's closed. 00:01:36.120 --> 00:01:37.455 "Not a problem," you think, 00:01:37.455 --> 00:01:39.741 "The next one can't be too far away." 00:01:39.741 --> 00:01:42.429 But then that next station never appears. 00:01:42.429 --> 00:01:44.998 Unfortunately, as you continue on your route, 00:01:44.998 --> 00:01:47.816 the reality of the situation starts to set in. 00:01:47.816 --> 00:01:49.665 More and more stations are closed 00:01:49.665 --> 00:01:51.511 or just erased from your map. 00:01:51.511 --> 00:01:53.500 All of a sudden, your routine trip 00:01:53.500 --> 00:01:55.088 has become a desperate search 00:01:55.088 --> 00:01:57.172 just to find somewhere safe to rest 00:01:57.172 --> 00:01:59.016 and refuel for the night. 00:01:59.662 --> 00:02:01.631 This scenario has become the reality 00:02:01.631 --> 00:02:03.890 for the majority of migrating song birds 00:02:03.890 --> 00:02:06.825 as human land development continues unchecked. 00:02:06.825 --> 00:02:09.322 Humans are altering important stop-over sites 00:02:09.322 --> 00:02:11.987 that birds have been using for generations. 00:02:11.987 --> 00:02:14.485 As migrators pass over the continent, 00:02:14.485 --> 00:02:15.896 they run a gauntlet of dangers, 00:02:15.896 --> 00:02:18.901 including pesticide ingestion in rural farmlands, 00:02:18.901 --> 00:02:21.192 habitat loss in suburban developments, 00:02:21.192 --> 00:02:23.905 as well as disorientation from light pollution, 00:02:23.905 --> 00:02:25.364 and even structure collision 00:02:25.364 --> 00:02:28.700 with tall, reflective glass buildings in cities. 00:02:28.700 --> 00:02:31.459 Of the estimated 20 billion individual birds 00:02:31.459 --> 00:02:33.735 that comprise the fall population, 00:02:33.735 --> 00:02:35.561 only about half will return 00:02:35.561 --> 00:02:37.387 to breed the following spring. 00:02:37.387 --> 00:02:39.213 Almost one billion of these deaths 00:02:39.213 --> 00:02:42.171 are attributed just to building collisions. 00:02:42.171 --> 00:02:44.009 With such astounding yearly losses, 00:02:44.009 --> 00:02:45.803 humans risk more than just the loss 00:02:45.803 --> 00:02:48.484 of the beautiful colors and songs of birds, 00:02:48.484 --> 00:02:51.479 they also play an important role in the ecosystem. 00:02:51.479 --> 00:02:53.507 Birds help with insect control, 00:02:53.507 --> 00:02:54.526 pollination, 00:02:54.526 --> 00:02:56.614 and disbursing seeds throughout the landscape. 00:02:56.614 --> 00:02:58.960 Without birds, the natural world 00:02:58.960 --> 00:03:00.263 would be a very different place. 00:03:00.263 --> 00:03:02.399 Although birds face an on-going threat 00:03:02.399 --> 00:03:03.841 from human land development, 00:03:03.841 --> 00:03:06.316 there are actions that we can all take to help. 00:03:06.316 --> 00:03:07.713 Many countries and local governements 00:03:07.713 --> 00:03:09.426 have already passed important laws 00:03:09.426 --> 00:03:12.255 that restrict the use of poisonous pesticides. 00:03:12.255 --> 00:03:14.582 By using more natural, plant-based products, 00:03:14.582 --> 00:03:16.557 we can maintain our farms and gardens 00:03:16.557 --> 00:03:18.642 without the dangerous side effects. 00:03:18.642 --> 00:03:21.753 In addition, as our global populations continue to grow 00:03:21.753 --> 00:03:23.858 and people need places to call home, 00:03:23.858 --> 00:03:26.162 green spaces can offer both bird habitat 00:03:26.162 --> 00:03:28.421 as well as a peaceful and natural place 00:03:28.421 --> 00:03:29.666 for us to enjoy. 00:03:30.404 --> 00:03:31.420 Small changes at home 00:03:31.420 --> 00:03:33.416 can also make a huge difference. 00:03:33.416 --> 00:03:34.415 By hanging up feeders 00:03:34.415 --> 00:03:36.954 and building bird houses in outdoor areas, 00:03:36.954 --> 00:03:38.947 we can provide much-needed food and safety 00:03:38.947 --> 00:03:40.825 during long migrations. 00:03:41.594 --> 00:03:43.155 Turning out lights in suburban 00:03:43.155 --> 00:03:43.994 and urban environments 00:03:43.994 --> 00:03:45.080 can also help birds 00:03:45.080 --> 00:03:47.296 that look for stars to navigate. 00:03:47.296 --> 00:03:49.331 With our help, these sky travellers 00:03:49.331 --> 00:03:51.383 can reach their destination safely, 00:03:51.383 --> 00:03:54.636 and hopefully keep returning year after year.