1 00:00:05,272 --> 00:00:08,575 European rabbits have annexed a coastal resort, 2 00:00:08,575 --> 00:00:13,780 starlings now soar in military formation. 3 00:00:13,780 --> 00:00:15,449 These alien populations 4 00:00:15,449 --> 00:00:18,819 are staking their claim to a new world. 5 00:00:18,819 --> 00:00:20,153 On the jagged coast 6 00:00:20,153 --> 00:00:22,389 of Canada's Eastern Shore. 7 00:00:22,389 --> 00:00:25,292 A delicate and diverse ecosystem 8 00:00:25,292 --> 00:00:28,795 thrives on the fringes of the continent. 9 00:00:28,795 --> 00:00:29,796 Welcome 10 00:00:29,796 --> 00:00:38,805 Welcome to the Wild, Wild East. 11 00:00:38,805 --> 00:00:41,541 NARRATOR: The story of European explorers 12 00:00:41,541 --> 00:00:44,845 arriving on these shores is well known. 13 00:00:44,845 --> 00:00:49,683 But what about the animals that came with them? 14 00:00:49,683 --> 00:00:52,286 European starlings have increased their population 15 00:00:52,286 --> 00:00:55,322 a million-times over since their introduction 16 00:00:55,322 --> 00:00:59,593 to North America by lovers of Shakespeare. 17 00:00:59,593 --> 00:01:02,162 Today they form massive murmurations 18 00:01:02,162 --> 00:01:06,633 that hang like clouds in the North American sky. 19 00:01:06,633 --> 00:01:08,568 Scientists call animals like starlings 20 00:01:08,568 --> 00:01:11,672 invasive species. 21 00:01:11,672 --> 00:01:13,507 Introduced wildlife, 22 00:01:13,507 --> 00:01:15,208 whose success in new territories 23 00:01:15,208 --> 00:01:17,144 impacts native species, 24 00:01:17,144 --> 00:01:21,848 and alters their new environment. 25 00:01:21,848 --> 00:01:26,119 These aren't just stories of conquest. 26 00:01:26,119 --> 00:01:29,089 How do invasive species like starlings 27 00:01:29,089 --> 00:01:36,463 adapt to life in their adopted habitat? 28 00:01:36,463 --> 00:01:41,234 It's the beginning of spring. 29 00:01:41,234 --> 00:01:45,872 The warm air fights back against the cold, 30 00:01:45,872 --> 00:01:52,112 but still, patches of snow remain. 31 00:01:52,112 --> 00:01:53,413 Bird feeders like this, 32 00:01:53,413 --> 00:01:56,116 intended for native chickadees and finches, 33 00:01:56,116 --> 00:01:58,251 also help European starlings 34 00:01:58,251 --> 00:02:04,358 survive the harsh winter of the Wild Wild East. 35 00:02:04,358 --> 00:02:05,792 This one has already begun 36 00:02:05,792 --> 00:02:13,467 to adorn its breeding plumage. 37 00:02:13,467 --> 00:02:14,334 Its bright yellow bill 38 00:02:14,334 --> 00:02:16,803 and glossy green and purple feathers, 39 00:02:16,803 --> 00:02:21,241 entice the opposite sex. 40 00:02:21,241 --> 00:02:22,776 This is a male, 41 00:02:22,776 --> 00:02:28,248 you can tell by the long scraggly feathers on his breast. 42 00:02:28,248 --> 00:02:30,250 This is a female, 43 00:02:30,250 --> 00:02:32,219 she has shorter breast feathers 44 00:02:32,219 --> 00:02:36,356 and a sleeker appearance. 45 00:02:36,356 --> 00:02:40,093 Males attract mates with their song. 46 00:02:47,467 --> 00:02:48,702 And will shadow females 47 00:02:48,702 --> 00:02:52,372 as they go about their daily activities. 48 00:02:55,175 --> 00:02:56,843 This looks like an attack, 49 00:02:56,843 --> 00:03:02,649 but it's actually two starlings mating. 50 00:03:02,649 --> 00:03:05,485 Starlings breed in early spring, 51 00:03:05,485 --> 00:03:09,723 surrounded by the last signs of winter. 52 00:03:09,723 --> 00:03:14,628 Like most birds the act happens on the ground. 53 00:03:14,628 --> 00:03:17,230 They rub together a combined urinary, 54 00:03:17,230 --> 00:03:21,134 digestive and reproductive opening called a cloaca, 55 00:03:21,134 --> 00:03:22,769 which swells during the mating season 56 00:03:22,769 --> 00:03:27,374 to transfer sperm from male to female. 57 00:03:27,374 --> 00:03:28,442 Once Starlings have mated, 58 00:03:28,442 --> 00:03:31,344 they stay together and spend the rest of the season 59 00:03:31,344 --> 00:03:34,047 caring for their young. 60 00:03:41,088 --> 00:03:44,491 When the spring air finally conquers winter's snow, 61 00:03:44,491 --> 00:03:47,661 Huge numbers of European starlings 62 00:03:47,661 --> 00:03:52,466 swarm fields just like this one. 63 00:03:52,466 --> 00:03:54,568 The parents are looking for earthworms, 64 00:03:54,568 --> 00:03:56,503 centipedes and other invertebrates 65 00:03:56,503 --> 00:04:03,110 to feed themselves and their newly hatched chicks. 66 00:04:03,110 --> 00:04:09,216 Starlings have an amazing technique for unearthing prey. 67 00:04:09,216 --> 00:04:14,254 Their jaw's musculature is wired in reverse. 68 00:04:14,254 --> 00:04:16,823 Its strength comes when opening their beak, 69 00:04:16,823 --> 00:04:20,060 not clenching it together. 70 00:04:20,060 --> 00:04:24,798 This allows them to easily excavate the ground. 71 00:04:24,798 --> 00:04:26,733 Confined to the nest, 72 00:04:26,733 --> 00:04:32,506 a clutch of 4 to 7 chicks eagerly awaits its next meal. 73 00:04:32,506 --> 00:04:36,776 Starlings are secondary cavity nesters. 74 00:04:36,776 --> 00:04:38,245 They make their home in pre-existing 75 00:04:38,245 --> 00:04:39,846 cracks and crevices, 76 00:04:39,846 --> 00:04:41,515 invading a woodpecker's hole, 77 00:04:41,515 --> 00:04:45,452 or occupying a man-made nest-box. 78 00:04:45,452 --> 00:04:47,554 One of the keys to starlings' success 79 00:04:47,554 --> 00:04:52,692 in the new world is that they're devoted parents. 80 00:04:52,692 --> 00:04:54,594 Both parents spend all their time and energy 81 00:04:54,594 --> 00:04:57,130 feeding the chicks until they're ready to fledge, 82 00:04:57,130 --> 00:04:59,566 three weeks after birth. 83 00:05:06,439 --> 00:05:09,242 On Nova Scotia's South Shore, 84 00:05:09,242 --> 00:05:12,045 White Point Beach Resort houses 85 00:05:12,045 --> 00:05:17,117 one of the world's most successful invaders, 86 00:05:17,117 --> 00:05:18,518 A creature that has conquered 87 00:05:18,518 --> 00:05:24,357 every continent except Antarctica. 88 00:05:24,357 --> 00:05:32,532 The European rabbit. 89 00:05:32,532 --> 00:05:34,834 Rabbits came to be known as bunnies, 90 00:05:34,834 --> 00:05:37,704 because their tails look like a bun, 91 00:05:37,704 --> 00:05:40,774 the Gaelic word for a bread roll. 92 00:05:40,774 --> 00:05:42,409 Along with those tails, 93 00:05:42,409 --> 00:05:44,744 European rabbits share their large ears 94 00:05:44,744 --> 00:05:45,612 and strong hind legs 95 00:05:45,612 --> 00:05:51,585 with 60 other species of leporidae. 96 00:05:51,585 --> 00:05:53,520 European rabbits, by far, 97 00:05:53,520 --> 00:05:56,156 are the most populous and widespread members 98 00:05:56,156 --> 00:05:59,559 of that mammalian family. 99 00:05:59,559 --> 00:06:00,794 That's because their broad diet 100 00:06:00,794 --> 00:06:02,796 and rapid reproductive rate 101 00:06:02,796 --> 00:06:05,632 makes them highly adaptable. 102 00:06:05,632 --> 00:06:06,800 But it's also because 103 00:06:06,800 --> 00:06:10,770 they've got a long history with humans. 104 00:06:10,770 --> 00:06:12,539 These fluffy conquistadors 105 00:06:12,539 --> 00:06:15,075 are native to Spain and Portugal, 106 00:06:15,075 --> 00:06:19,479 but have travelled across the world with people. 107 00:06:19,479 --> 00:06:24,751 First as a food source, but more recently as a pet. 108 00:06:24,751 --> 00:06:26,453 These rabbits are the same species 109 00:06:26,453 --> 00:06:31,491 many keep as furry companions. 110 00:06:31,491 --> 00:06:34,127 In parts of the world with fewer predators 111 00:06:34,127 --> 00:06:37,163 and tamer winters, invasive rabbit populations 112 00:06:37,163 --> 00:06:40,400 have exploded exponentially. 113 00:06:40,400 --> 00:06:42,636 These alien intruders' massive populations 114 00:06:42,636 --> 00:06:45,272 can devastate native flora and fauna, 115 00:06:45,272 --> 00:06:51,111 impacting the biodiversity of these areas. 116 00:06:51,111 --> 00:06:55,482 In Australia, 24 European rabbits released in 1859 117 00:06:55,482 --> 00:06:58,351 grew to 600 million 118 00:06:58,351 --> 00:07:00,687 in less than a century. 119 00:07:00,687 --> 00:07:03,423 On Canada's more temperate west coast, 120 00:07:03,423 --> 00:07:05,025 an exploding population 121 00:07:05,025 --> 00:07:08,161 at the University of Victoria in British Columbia 122 00:07:08,161 --> 00:07:11,398 led to 900 rabbits being trapped, neutered 123 00:07:11,398 --> 00:07:15,268 and taken to shelters as far away as Texas. 124 00:07:15,268 --> 00:07:17,370 The outbreak here at White Point Resort 125 00:07:17,370 --> 00:07:19,606 in Nova Scotia began as 126 00:07:19,606 --> 00:07:22,742 a bunny-sitting experiment gone wrong. 127 00:07:22,742 --> 00:07:24,244 More than two decades ago, 128 00:07:24,244 --> 00:07:26,780 a staff member was taking care of 2 or 3 rabbits 129 00:07:26,780 --> 00:07:29,282 in the resort's boathouse. 130 00:07:29,282 --> 00:07:34,087 They escaped, and the population grew. 131 00:07:38,491 --> 00:07:44,197 The colony has been here for more than 20 years now. 132 00:07:44,197 --> 00:07:46,132 The average population holding steady 133 00:07:46,132 --> 00:07:49,202 at 30 rabbits. 134 00:07:51,237 --> 00:07:53,173 That's because Mother Nature 135 00:07:53,173 --> 00:07:56,343 has a hand in population control. 136 00:07:56,343 --> 00:08:01,548 The surrounding woods are full of predators, 137 00:08:01,548 --> 00:08:03,450 and every year the winter 138 00:08:03,450 --> 00:08:07,020 devastates the colony's numbers. 139 00:08:07,020 --> 00:08:10,123 In order to survive, the White Point Beach rabbits 140 00:08:10,123 --> 00:08:17,630 need to rely on their wild instincts. 141 00:08:17,630 --> 00:08:20,433 100 miles up the Nova Scotia coast 142 00:08:20,433 --> 00:08:22,135 in the city of Halifax, 143 00:08:22,135 --> 00:08:26,239 a stretch of boardwalk traces the waterfront. 144 00:08:26,239 --> 00:08:28,808 Here you'll find locals, tourists 145 00:08:28,808 --> 00:08:32,078 and European starlings. 146 00:08:32,078 --> 00:08:33,313 Like humans, 147 00:08:33,313 --> 00:08:36,750 starlings are omnivores with an expansive diet, 148 00:08:36,750 --> 00:08:40,353 so they're commonly found around people and cities. 149 00:08:40,353 --> 00:08:42,088 The hatchlings born last spring 150 00:08:42,088 --> 00:08:44,290 are beginning to resemble their parents, 151 00:08:44,290 --> 00:08:46,226 except for their dull brown heads 152 00:08:46,226 --> 00:08:50,230 and petite appearance. 153 00:08:50,230 --> 00:08:51,731 At the end of the breeding season 154 00:08:51,731 --> 00:08:55,268 all starlings adopt a drab plumage, 155 00:08:55,268 --> 00:09:00,306 and a matching black beak. 156 00:09:00,306 --> 00:09:02,776 Starlings are incredibly intelligent birds, 157 00:09:02,776 --> 00:09:08,314 with exceptional skills as mimics. 158 00:09:08,314 --> 00:09:11,251 Their mimicry even caught the attention of Mozart, 159 00:09:11,251 --> 00:09:12,786 who taught one to sing 160 00:09:12,786 --> 00:09:16,589 his Piano Concerto in G Major. 161 00:09:16,589 --> 00:09:19,159 It also inspired William Shakespeare 162 00:09:19,159 --> 00:09:21,327 to write them into one of his plays, 163 00:09:21,327 --> 00:09:24,297 Henry IV, Part One. 164 00:09:24,297 --> 00:09:26,032 It was pen stroke 165 00:09:26,032 --> 00:09:31,271 that changed the bird's fate forever. 166 00:09:31,271 --> 00:09:35,708 In 1890, a group called the American Acclimation Society 167 00:09:35,708 --> 00:09:39,045 wanted to introduce all the birds in the bard's plays 168 00:09:39,045 --> 00:09:41,147 to the New World. 169 00:09:41,147 --> 00:09:44,150 At the time, the concept of a potentially harmful 170 00:09:44,150 --> 00:09:47,754 "invasive species" was unknown, 171 00:09:47,754 --> 00:09:49,189 and the group thought the introductions 172 00:09:49,189 --> 00:09:52,192 would add a European flare to North America. 173 00:09:52,192 --> 00:09:55,128 One hundred European starlings 174 00:09:55,128 --> 00:09:58,665 were shipped from England and set free in Central Park. 175 00:09:58,665 --> 00:10:04,304 Since then, the population has exploded. 176 00:10:04,304 --> 00:10:07,440 There are 200 million European starlings 177 00:10:07,440 --> 00:10:09,242 in North American today, 178 00:10:09,242 --> 00:10:11,244 and they've colonized the sky 179 00:10:11,244 --> 00:10:14,447 from Tijuana to Alaska. 180 00:10:14,447 --> 00:10:17,450 The American Acclimation Society initiated the starling invasion 181 00:10:17,450 --> 00:10:20,186 but it was widespread changes 182 00:10:20,186 --> 00:10:22,121 to the landscape of North America 183 00:10:22,121 --> 00:10:23,656 at the turn of the 20th century 184 00:10:23,656 --> 00:10:29,829 that paved the way for the starling's expansion. 185 00:10:29,829 --> 00:10:32,599 Clear-cutting opened up new territories 186 00:10:32,599 --> 00:10:35,502 for these lowland birds. 187 00:10:35,502 --> 00:10:37,504 The growth of the agricultural industry 188 00:10:37,504 --> 00:10:40,507 resulted in more cultivated fields of grain 189 00:10:40,507 --> 00:10:42,809 and other plants that attract the insects 190 00:10:42,809 --> 00:10:46,446 starlings like to eat. 191 00:10:46,446 --> 00:10:52,318 Now starlings have become a major pest on farmlands. 192 00:10:52,318 --> 00:10:54,654 Modern cities provided new nesting locations 193 00:10:54,654 --> 00:10:57,757 and food sources. 194 00:10:57,757 --> 00:11:01,194 Starlings have also moved into other bird's nests. 195 00:11:01,194 --> 00:11:02,729 Few North American immigrants 196 00:11:02,729 --> 00:11:04,797 benefited more from the Industrial Age 197 00:11:04,797 --> 00:11:07,667 than the European starling. 198 00:11:11,271 --> 00:11:13,706 Back along Nova Scotia's south shore 199 00:11:13,706 --> 00:11:17,110 at White Point Resort, it's summer time, 200 00:11:17,110 --> 00:11:19,712 the peak of tourist season. 201 00:11:23,616 --> 00:11:26,753 But while the visitors enjoy the cabins above, 202 00:11:26,753 --> 00:11:32,759 the rabbits annex the territory below. 203 00:11:32,759 --> 00:11:35,261 European rabbits are herbivores 204 00:11:35,261 --> 00:11:43,269 and will eat almost any vegetation they can reach. 205 00:11:43,269 --> 00:11:44,837 They're mixed feeders, 206 00:11:44,837 --> 00:11:48,308 browsing shrubs for leaves, fruits or buds, 207 00:11:48,308 --> 00:11:51,311 and also grazing on grass. 208 00:11:53,546 --> 00:11:56,516 European rabbits are a gregarious bunch, 209 00:11:56,516 --> 00:11:59,719 living in tight social units called warrens 210 00:11:59,719 --> 00:12:04,057 that consist of up to 10 individuals. 211 00:12:04,057 --> 00:12:06,159 The warren is also the name 212 00:12:06,159 --> 00:12:07,627 of the elaborate network of tunnels 213 00:12:07,627 --> 00:12:11,297 that connect the burrows rabbits dig. 214 00:12:11,297 --> 00:12:12,432 A trip down the rabbit hole 215 00:12:12,432 --> 00:12:16,069 reveals the hidden world of rabbits. 216 00:12:16,069 --> 00:12:17,303 This maze of tunnels 217 00:12:17,303 --> 00:12:20,173 reaches ten feet underground, 218 00:12:20,173 --> 00:12:24,444 and spreads across 2,000 square feet. 219 00:12:26,679 --> 00:12:32,085 The warren is the center of their colony at the resort. 220 00:12:32,085 --> 00:12:34,554 It's also where females give birth, 221 00:12:34,554 --> 00:12:36,155 in the burrows underground, 222 00:12:36,155 --> 00:12:38,758 competing with other does for the best nesting sites, 223 00:12:38,758 --> 00:12:42,462 then marking them with their powerful urine. 224 00:12:42,462 --> 00:12:43,830 Throughout the warren there are separate areas 225 00:12:43,830 --> 00:12:46,366 for urinating or defecating, 226 00:12:46,366 --> 00:12:48,501 sleeping, and rearing babies. 227 00:12:48,501 --> 00:12:54,374 Each warren can house a colony of up to 10 rabbits. 228 00:12:54,374 --> 00:12:56,509 Burrows offer a refuge from danger 229 00:12:56,509 --> 00:13:01,147 so rabbits don't venture far from their warren. 230 00:13:01,147 --> 00:13:02,649 Like most prey animals, 231 00:13:02,649 --> 00:13:05,618 rabbits are extremely vigilant. 232 00:13:05,618 --> 00:13:08,254 Their eyes are positioned high on their head 233 00:13:08,254 --> 00:13:10,323 so they can see avian predators, 234 00:13:10,323 --> 00:13:13,192 like eagles flying above. 235 00:13:15,328 --> 00:13:18,831 If a rabbit is stressed, its nose twitches frantically, 236 00:13:18,831 --> 00:13:23,536 sensing the air for any nearby predators, like foxes. 237 00:13:23,536 --> 00:13:27,073 The twitch increases the olfactory receptors' 238 00:13:27,073 --> 00:13:29,509 exposure to airborne particles, 239 00:13:29,509 --> 00:13:36,215 so the rabbit knows when the fox has moved on. 240 00:13:36,215 --> 00:13:39,152 Their iconic ears are like two giant antennae 241 00:13:39,152 --> 00:13:40,486 on the top of their heads 242 00:13:40,486 --> 00:13:44,524 intercepting sound waves from every direction. 243 00:13:44,524 --> 00:13:47,226 With danger lurking around each corner, 244 00:13:47,226 --> 00:13:50,163 this rabbit knows if it senses 245 00:13:50,163 --> 00:13:53,166 an American mink watching from the woods, 246 00:13:53,166 --> 00:13:55,535 It had better run. 247 00:14:00,773 --> 00:14:05,278 Rabbits' best defenses are quickness and agility. 248 00:14:05,278 --> 00:14:07,113 Rabbits can reach an impressive 249 00:14:07,113 --> 00:14:09,415 36 miles per hour 250 00:14:09,415 --> 00:14:11,284 and can rapidly pivot in new directions 251 00:14:11,284 --> 00:14:16,255 to escape predators. 252 00:14:16,255 --> 00:14:17,757 When there are no nearby threats, 253 00:14:17,757 --> 00:14:20,593 rabbits practice their evasion skills 254 00:14:20,593 --> 00:14:24,163 by chasing each other. 255 00:14:24,163 --> 00:14:26,265 They have specially padded feet 256 00:14:26,265 --> 00:14:30,470 to absorb the shock of running and jumping. 257 00:14:30,470 --> 00:14:32,772 Prey animals sustain great losses, 258 00:14:32,772 --> 00:14:37,376 only 10% of bunnies make it through their first year. 259 00:14:43,182 --> 00:14:45,084 But rabbits have another adaptation 260 00:14:45,084 --> 00:14:46,686 that ensures their success, 261 00:14:50,490 --> 00:14:54,127 and it's earned them quite the reputation. 262 00:14:57,430 --> 00:15:01,801 Rabbits can mate four times in one year. 263 00:15:01,801 --> 00:15:05,571 After giving birth, does immediately enter estrus. 264 00:15:05,571 --> 00:15:10,042 Mating actually induces ovulation in females. 265 00:15:10,042 --> 00:15:11,544 So a doe can be pregnant 266 00:15:11,544 --> 00:15:14,413 for up to eight straight months, 267 00:15:14,413 --> 00:15:17,049 a continuous cycle of pregnancy, birth 268 00:15:17,049 --> 00:15:19,185 and then pregnancy again. 269 00:15:19,185 --> 00:15:20,219 Each doe can birth 270 00:15:20,219 --> 00:15:23,656 between 30 and 40 kits annually. 271 00:15:27,760 --> 00:15:30,496 Up to 12 kits are born at a time 272 00:15:30,496 --> 00:15:35,768 in fur-lined nests inside the warren. 273 00:15:35,768 --> 00:15:39,605 They're altricial, deaf, blind, hairless 274 00:15:39,605 --> 00:15:44,477 and 100% dependent on their mother. 275 00:15:44,477 --> 00:15:46,412 Their mother only nurses her kits 276 00:15:46,412 --> 00:15:50,249 for a few minutes each day. 277 00:15:50,249 --> 00:15:51,517 The nutrient-rich milk 278 00:15:51,517 --> 00:15:54,387 can sustain the young for 24 hours, 279 00:15:54,387 --> 00:15:56,656 so the mother visits her kits infrequently, 280 00:15:56,656 --> 00:16:00,626 which reduces a predator's attention to the warren. 281 00:16:00,626 --> 00:16:06,165 In a month's time, the babies will leave the warren. 282 00:16:06,165 --> 00:16:08,234 They will fend for themselves, 283 00:16:08,234 --> 00:16:11,470 evading predators and fighting to survive 284 00:16:11,470 --> 00:16:14,740 against the devilish winter ahead. 285 00:16:17,777 --> 00:16:21,581 By the time the fall leaves begin to show, 286 00:16:21,581 --> 00:16:24,050 the starlings born this past spring 287 00:16:24,050 --> 00:16:26,786 will have reached breeding age themselves. 288 00:16:26,786 --> 00:16:28,521 The population reaches its peak 289 00:16:28,521 --> 00:16:32,158 just before the onslaught of winter. 290 00:16:32,158 --> 00:16:33,392 This time of year, 291 00:16:33,392 --> 00:16:38,631 the already gregarious group grows even larger. 292 00:16:38,631 --> 00:16:41,267 For this nearby peregrine falcon, 293 00:16:41,267 --> 00:16:42,602 an individual starling 294 00:16:42,602 --> 00:16:48,507 could make a satisfying supper. 295 00:16:48,507 --> 00:16:51,611 But a mob of starlings has many eyes, 296 00:16:51,611 --> 00:16:54,680 and many look outs. 297 00:16:54,680 --> 00:16:59,118 The defense begins with just one individual, 298 00:16:59,118 --> 00:17:02,088 then it grows, 299 00:17:02,088 --> 00:17:03,723 and grows. 300 00:17:04,257 --> 00:17:07,026 The falcon's overwhelmed by the numbers 301 00:17:07,026 --> 00:17:10,162 and can't pinpoint an individual. 302 00:17:10,162 --> 00:17:11,764 In some places these murmurations 303 00:17:11,764 --> 00:17:14,734 can consist of over a thousand birds, 304 00:17:14,734 --> 00:17:18,271 all moving in concert with each other. 305 00:17:21,440 --> 00:17:24,744 When one shifts directions, 306 00:17:24,744 --> 00:17:27,280 they all follow. 307 00:17:27,280 --> 00:17:30,216 An aerial ballet. 308 00:17:33,753 --> 00:17:36,722 Each bird is watching seven others. 309 00:17:36,722 --> 00:17:39,258 The movement of one spreads across a flock 310 00:17:39,258 --> 00:17:41,093 the length of a football field, 311 00:17:41,093 --> 00:17:44,597 in a fraction of a second. 312 00:17:44,597 --> 00:17:46,265 The individual shifts 313 00:17:46,265 --> 00:17:50,703 are too quick for the human eye. 314 00:17:50,703 --> 00:17:55,741 The flock appears to move with one mind. 315 00:17:55,741 --> 00:17:58,477 Theoretical physicists recorded murmurations 316 00:17:58,477 --> 00:18:00,212 with high-speed cameras, 317 00:18:00,212 --> 00:18:06,052 then used computers to model the starlings' movements. 318 00:18:06,052 --> 00:18:09,355 Amazingly, the results show these undulating clouds 319 00:18:09,355 --> 00:18:11,057 closely resemble the movement 320 00:18:11,057 --> 00:18:13,693 of avalanches and waves, 321 00:18:13,693 --> 00:18:16,495 patterns in movement that scientists associate 322 00:18:16,495 --> 00:18:19,498 with state-of-the-art physics. 323 00:18:23,302 --> 00:18:26,339 Still, no one knows exactly how information 324 00:18:26,339 --> 00:18:29,675 whizzes through the flock like lightning. 325 00:18:29,675 --> 00:18:33,312 It's truly an awesome natural phenomenon. 326 00:18:38,317 --> 00:18:41,320 Winter on the North Atlantic coast 327 00:18:41,320 --> 00:18:44,323 is brutal for wildlife. 328 00:18:44,323 --> 00:18:46,158 Plummeting temperatures, 329 00:18:46,158 --> 00:18:48,060 unpredictable weather, 330 00:18:48,060 --> 00:18:51,731 and very little food to go around. 331 00:18:51,731 --> 00:18:53,399 It's enough to stop most invaders 332 00:18:53,399 --> 00:18:55,134 before they can even gain a foothold 333 00:18:55,134 --> 00:18:57,536 in new territories. 334 00:18:58,404 --> 00:19:00,673 The cold season ravages the rabbits 335 00:19:00,673 --> 00:19:05,478 at White Point Resort by imposing a natural cull. 336 00:19:05,478 --> 00:19:06,512 At this time of year, 337 00:19:06,512 --> 00:19:11,617 rabbits use most of their energy to stay warm. 338 00:19:11,617 --> 00:19:14,186 By January their population at the resort 339 00:19:14,186 --> 00:19:15,354 typically falls from 80, 340 00:19:15,354 --> 00:19:17,390 the summer-time peak, 341 00:19:17,390 --> 00:19:19,291 to just 30. 342 00:19:28,634 --> 00:19:31,404 In Nova Scotia the winters do the job 343 00:19:31,404 --> 00:19:33,205 of population control, 344 00:19:33,205 --> 00:19:35,641 with a little help from a native predator 345 00:19:35,641 --> 00:19:38,411 in the nearby woods, 346 00:19:38,411 --> 00:19:42,715 The American mink hunts all year, 347 00:19:42,715 --> 00:19:45,418 and the winter's hard on this carnivorous member 348 00:19:45,418 --> 00:19:48,454 of the weasel family too. 349 00:19:48,454 --> 00:19:50,322 Snatching one of the young rabbits 350 00:19:50,322 --> 00:19:53,259 would help it survive until spring. 351 00:19:57,163 --> 00:19:59,265 Rabbits hide from minks in the warren, 352 00:19:59,265 --> 00:20:01,100 most of the day, 353 00:20:01,100 --> 00:20:03,469 but must come out to find food. 354 00:20:03,469 --> 00:20:05,471 Normally, their winter diet 355 00:20:05,471 --> 00:20:07,673 consists heavily of tree bark. 356 00:20:07,673 --> 00:20:10,276 It's tough to digest, so, 357 00:20:10,276 --> 00:20:11,644 to extract every last nutrient, 358 00:20:11,644 --> 00:20:15,181 they actually eat their poop after defecating, 359 00:20:15,181 --> 00:20:17,650 and send it through their gut several times over. 360 00:20:17,650 --> 00:20:19,218 Luckily for these rabbits, 361 00:20:19,218 --> 00:20:23,355 the resort is open year-round. 362 00:20:23,355 --> 00:20:24,790 Inside, the workers are busy 363 00:20:24,790 --> 00:20:30,396 preparing a meal for the rabbits. 364 00:20:30,396 --> 00:20:33,499 A little extra food sprinkled along the pathways 365 00:20:33,499 --> 00:20:37,636 helps some of the bunnies survive until next spring. 366 00:20:37,636 --> 00:20:41,640 It's a win-win situation. 367 00:20:41,640 --> 00:20:48,180 The bunnies get a leg-up they wouldn't otherwise have. 368 00:20:48,180 --> 00:20:49,782 And come spring, 369 00:20:49,782 --> 00:20:56,188 the rabbits will help draw in flocks of tourists. 370 00:20:56,188 --> 00:20:58,524 Meanwhile, the starlings also take advantage 371 00:20:58,524 --> 00:21:00,726 of people's generosity in the winter 372 00:21:00,726 --> 00:21:02,661 by dominating bird feeders. 373 00:21:09,168 --> 00:21:11,237 Many people leave out grain and seeds 374 00:21:11,237 --> 00:21:12,738 thinking they're helping shepherd blue jays 375 00:21:12,738 --> 00:21:18,410 and chickadees through the long winter months, 376 00:21:18,410 --> 00:21:20,412 unaware they're actually bolstering 377 00:21:20,412 --> 00:21:22,715 the starling population. 378 00:21:24,116 --> 00:21:26,652 Starlings' aggressive feeding and nesting patterns 379 00:21:26,652 --> 00:21:28,721 make them frequent scapegoats 380 00:21:28,721 --> 00:21:31,090 for the decline of avian populations 381 00:21:31,090 --> 00:21:33,526 across North America. 382 00:21:35,127 --> 00:21:36,829 It's widely believed that starlings 383 00:21:36,829 --> 00:21:39,131 displace their New World cousins 384 00:21:39,131 --> 00:21:44,770 by outcompeting them for food and nesting locations. 385 00:21:44,770 --> 00:21:47,439 But the jury's still out on this. 386 00:21:47,439 --> 00:21:51,710 Most evidence is more anecdotal than scientific. 387 00:21:53,779 --> 00:21:56,682 Starlings aren't as much of a problem for other birds, 388 00:21:56,682 --> 00:21:59,218 as they are for people, 389 00:21:59,218 --> 00:22:03,222 who accuse them of being messy, noisy and greedy. 390 00:22:03,222 --> 00:22:05,291 It may have been human intervention 391 00:22:05,291 --> 00:22:10,062 that brought European starlings to North America, 392 00:22:10,062 --> 00:22:12,298 but their success here is the consequence 393 00:22:12,298 --> 00:22:16,135 of their resourcefulness and intelligence. 394 00:22:28,847 --> 00:22:31,684 Invasive species may have already changed 395 00:22:31,684 --> 00:22:34,587 the North American wild. 396 00:22:36,388 --> 00:22:38,624 But ecologists claim that the idea 397 00:22:38,624 --> 00:22:41,393 of an unchanging balanced ecosystem 398 00:22:41,393 --> 00:22:43,295 is an illusion. 399 00:22:43,862 --> 00:22:47,499 Nature is always in flux. 400 00:22:52,538 --> 00:22:54,506 And the new order of things 401 00:22:54,506 --> 00:22:57,076 will change again tomorrow. 402 00:22:58,510 --> 00:23:01,347 European starlings have made an indelible mark 403 00:23:01,347 --> 00:23:04,750 on the North American sky. 404 00:23:04,750 --> 00:23:06,619 But the most recent data suggests 405 00:23:06,619 --> 00:23:11,123 their numbers have begun to level off. 406 00:23:11,123 --> 00:23:12,791 And while European rabbit outbreaks 407 00:23:12,791 --> 00:23:15,461 may run rampant elsewhere, 408 00:23:15,461 --> 00:23:17,296 at least Mother Nature 409 00:23:17,296 --> 00:23:22,334 controls the population along Nova Scotia's coast. 410 00:23:23,802 --> 00:23:26,472 The invaders have been granted citizenship 411 00:23:26,472 --> 00:23:28,474 in the Wild Wild East. 412 00:23:28,474 --> 00:23:38,517 ♪ THEME MUSIC ♪ 413 00:23:38,517 --> 00:23:43,822 ♪ THEME MUSIC ♪ 414 00:23:43,822 --> 00:23:53,032 ♪ THEME MUSIC ♪