BBC Wildlife Super Mums The Smart Investors
Transcript
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00:40The West Coast of America.
00:43It's a landscape full of extremes.
00:46Bringing up a family here would be a challenge to any mother.
00:50So how do the mothers in this neighbourhood succeed?
00:54By far the most dynamic area is the coastline.
00:59It's famous for its storms, but it's also rich in life.
01:07The cold shoreline is a difficult place to live.
01:12For a single mother, it's challenging.
01:16Yet this is where a sea otter mother lives and brings up her pups.
01:21Dad plays no part.
01:23Mum is left quite literally holding the baby.
01:29Otters only produce one pup at a time.
01:32It's hard enough for the mother to survive here,
01:35let alone bring up a demanding pup.
01:40The pup comes with its own fluffy life jacket.
01:43Keeping it groomed is one of mother's essential tasks,
01:46for if such a tiny pup got waterlogged,
01:48it would be fatally chilled within minutes.
01:52She supports the pup on her belly, warming and feeding it.
01:58But like all busy mothers, she needs to grab a meal when she can,
02:02and to do that means abandoning the pup on the surface
02:05while she goes in search of food.
02:11The water is so cold,
02:12she needs to eat about a third of her own body weight a day
02:16just to keep warm.
02:18And producing rich, creamy milk is an extra burden.
02:22The richest of our ice creams is only 15% fat.
02:27Her milk is a luxurious 25%.
02:35Not every dive is successful,
02:37and she may need to move around the coast if she's to find a meal.
02:42Sea otters are fussy feeders.
02:46Sea otters are fussy feeders,
02:48and each individual has its own special favourites.
02:52If octopus is on her menu, she needs to dive deep and search hard.
02:58But it's worth the effort.
03:00One octopus makes a substantial meal.
03:04Other otters prefer shellfish or crabs,
03:07not the easiest of snacks to open.
03:10But with practice, they can use rocks to smash open their catch.
03:16MUSIC
03:23As the pup's baby fur changes to a waterproof coat,
03:27the youngster gets better at swimming and diving
03:30and gradually learns to become independent.
03:33By two months, mum starts to share her solid meals,
03:36and her favourite snacks will become her baby's favourites too.
03:41But even when it's old enough to catch its own dinner,
03:43it still pesters mum for an easy meal.
03:49Otter pups have a lot to learn about their complex home,
03:52and the more time and energy the mother invests in them,
03:55the more likely she is to succeed in passing on her genes.
03:59And experience is worth a lot here.
04:02Older mothers are far more successful than young ones.
04:06Even so, there's still room for trial and error.
04:13In her lifetime, this mother could have ten pups,
04:16but over half will die before they mature.
04:19So otters have a high-investment, high-risk strategy,
04:23producing just one high-maintenance offspring.
04:28But in poor conditions,
04:30a sea-urchin mother has a very different approach.
04:33She's on almost everyone's menu as a tasty snack,
04:36so she only has a short life.
04:39Producing one baby in a year would be no good for her.
04:44She has a very different strategy.
04:47In one year, she produces 200,000 eggs.
04:51And if she can get within one metre of a sperm-producing male,
04:55nearly all of these eggs could be fertilised.
05:02But she has to leave the rest of their development to fate.
05:06In her unpredictable environment,
05:08it's better to produce one egg at a time,
05:11so that she can keep the rest for herself.
05:14She has to leave the rest of their development to fate.
05:17In her unpredictable environment,
05:19it's better to produce a huge family
05:21and then let the babies fend for themselves.
05:24So, in the same neighbourhood,
05:26two mothers have found two totally different ways of mothering,
05:30playing the numbers game or lavishing attention on a single baby.
05:37Other mothers go for two or three babies every other year.
05:44A mother black bear lies dormant in her den.
05:49She gives birth to her cubs in the dead of winter,
05:52so they're ready to take advantage of the spring and summer months.
05:59But winter in the Rockies is cold and hostile.
06:02With temperatures as low as 12 degrees below freezing,
06:06mums that live here are forced to shut down their bodies.
06:11Her heart rate drops to eight beats a minute
06:14and she breathes only once every 45 seconds.
06:17She doesn't eat, drink or defecate, but her body stays warm.
06:23She can remain like this all winter,
06:25transferring warmth and food into the cubs.
06:29She's living off the fat reserves she accumulated during the autumn.
06:33By gorging on carrion, nuts and berries,
06:36she put on nearly 20 kilos a week.
06:45When her cubs were born, they weighed only 200 grams,
06:49but in a few months, mother's milk will have doubled.
06:54Eventually, the temperature rises.
06:57Spring has arrived.
06:59Another phase of mother bear's strategy begins.
07:07The cubs are now in the thick of spring,
07:09and the mother bear is ready to go.
07:13The cubs are now in the thick of spring,
07:16and the mother bear is ready to go.
07:18Spring begins.
07:25Now the cubs are free to explore their new world.
07:29Mum, on the other hand, takes time out to just eat and eat and eat.
07:49While fasting and feeding her cubs,
07:51she may have lost 40% of her body weight.
07:55But despite being weak and thin,
07:57she still has to care on her own for her boisterous toddlers.
08:06For the next two years, she will protect them
08:09and teach them the complex skills of forest survival.
08:12And because she's caring for them, they have time to play.
08:16Play is an essential way for toddlers to exercise their muscles and brains
08:21and become successful adults.
08:26Black bears can live for 25 years,
08:29and so a bear mother can easily afford to invest two years
08:33in raising each set of cubs.
08:39The outstanding mothers we've seen in America are not alone.
08:42Supermums exist all over the world.
08:46But even supermums can't afford to rest on their laurels
08:49in this changing and dynamic world.
08:53So for mums, whether super or not, a mother's work is never done.
09:08Say goodbye to Martin and Sonia.
09:10We're back with the EastEnders Omnibus next here on BBC One.
09:13And over on BBC Two,
09:14Sabah Douglas-Hamilton reflects on my life with animals.