Mammals

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0:00:02 > 0:00:04Some animals are notoriously difficult to see.

0:00:04 > 0:00:08Can you see it? You don't know what you're looking at, do you?!

0:00:08 > 0:00:10Many only come out at night...

0:00:10 > 0:00:12No, we can't come in here now.

0:00:12 > 0:00:14Others hide in holes or up trees...

0:00:14 > 0:00:18It's a bit deeper there, Gordon. Gordon!

0:00:18 > 0:00:21And some just like to keep their heads down...

0:00:21 > 0:00:25I'm checking whether this is one woozle or two weasels or whatever Christopher Robin said.

0:00:25 > 0:00:32But this doesn't deter the devoted and plucky folk who make up Britain's secret wild army.

0:00:32 > 0:00:38Four animals, four amateur naturalists, four inspiring stories.

0:01:01 > 0:01:03BIRDSONG # Dee, de-de, dee, dee... #

0:01:03 > 0:01:08Gordon, what have we got singing over there at the moment? Willow warbler, or a black cap?

0:01:08 > 0:01:13It takes more than a spot of rain to put these three intrepid gentlemen off their regular wildlife mission.

0:01:13 > 0:01:15We were waiting for that.

0:01:15 > 0:01:18Think there was a stitchwort there, and a campion...

0:01:18 > 0:01:22In the depths of a Devonshire wood are 50 nest boxes,

0:01:22 > 0:01:27all carefully mapped and meticulously numbered, and all of them need inspecting.

0:01:29 > 0:01:32This is more like jungle exploration!

0:01:35 > 0:01:39Leading this dedicated band is retired biology teacher Tom Maddock.

0:01:39 > 0:01:41Where is it?

0:01:41 > 0:01:43Oh, there we are.

0:01:43 > 0:01:44Right.

0:01:45 > 0:01:49This is going on this stone, then I can open the box.

0:01:49 > 0:01:54I always think this is like Christmas, cos you never quite know what you're gonna find.

0:01:54 > 0:01:58And, in fact, what we've got is a brood of blue tits.

0:01:58 > 0:02:02That was box number one and 49 to go!

0:02:04 > 0:02:06Something's been in there, a slug...?

0:02:06 > 0:02:09Finding a nest of blue tits might be treasure enough for some,

0:02:09 > 0:02:14but Tom and his team are after something much more unusual.

0:02:14 > 0:02:20I can see, um, shreds of plant material, so I'm gonna take this one down.

0:02:20 > 0:02:22Ten or 15, Gordon?

0:02:33 > 0:02:35Oh! Ha-ha! Now...

0:02:37 > 0:02:40Wonderful, isn't it? Look at that. Isn't that brilliant?

0:02:40 > 0:02:44What we have here is a torpid dormouse. There we are.

0:02:48 > 0:02:51This is the reason for our quest.

0:02:51 > 0:02:57It's a delightful find, but it's not just for personal pleasure.

0:02:57 > 0:03:01Tom and his friends are part of the National Dormouse Monitoring scheme,

0:03:01 > 0:03:05volunteers who are qualified to handle and study this rare and endearing mammal.

0:03:05 > 0:03:08No other rodent spends half its life sleeping.

0:03:08 > 0:03:13These will sleep for six months of the year, and they will normally

0:03:13 > 0:03:18start to wake up about midday, they're late risers.

0:03:18 > 0:03:21He doesn't want to show me his special parts. Hee-hee!

0:03:22 > 0:03:23He's very coy, this one.

0:03:25 > 0:03:28I would say...that we have...

0:03:30 > 0:03:31We have a male here.

0:03:31 > 0:03:34You can see a tiny penis.

0:03:35 > 0:03:38So what I'm gonna do next is weigh the animal...

0:03:41 > 0:03:43This one's 19.8.

0:03:43 > 0:03:4519.8.

0:03:45 > 0:03:48A good weight.

0:03:50 > 0:03:54Tom's love of wildlife is part of a great British tradition.

0:03:54 > 0:03:59For centuries, like-minded amateur naturalists have watched and recorded everything that moves

0:03:59 > 0:04:03and grows, making Britain the best-studied place on Earth.

0:04:04 > 0:04:08Like many others, Tom was first inspired when he was just a boy,

0:04:08 > 0:04:12and it's all down to this man, HG Hurrell.

0:04:12 > 0:04:18Oh, Lord, for what we are about to receive, make us truly thankful, for Christ's sake. Amen.

0:04:18 > 0:04:22Hurrell's family is a family of naturalists.

0:04:22 > 0:04:27His younger son, Kenneth, his daughter Elaine, who runs a section of the Bristol Naturalists Society.

0:04:27 > 0:04:31Their mutual love of wildlife forms a deep family bond of understanding.

0:04:31 > 0:04:34Hurrell was himself an amateur naturalist.

0:04:34 > 0:04:36His knowledge and interest was infectious.

0:04:36 > 0:04:40HG came to school once and showed films at school.

0:04:40 > 0:04:43I was trapped by that, really.

0:04:43 > 0:04:46And he was to me something of an idol.

0:04:46 > 0:04:50And I thought, "This is what natural history's all about."

0:04:52 > 0:05:00HG died in 1981, but his daughter Elaine, now in her 70s, is still a good friend, and mentor, to Tom.

0:05:00 > 0:05:01Hello, Elaine.

0:05:01 > 0:05:03Hello, Tom. Come inside.

0:05:03 > 0:05:08Right, we've managed to complete the whole check. There's our first dormouse,

0:05:08 > 0:05:12- in number nine, nicely torpid, so that made for ease of handling. - Oh, really?

0:05:12 > 0:05:14- Yeah, so that was good.- Yeah.

0:05:14 > 0:05:16So that was that one.

0:05:16 > 0:05:20It means a lot to Elaine that Tom is carrying on the dormouse work

0:05:20 > 0:05:23she and her father started back in the 1950s.

0:05:23 > 0:05:25We've got three in here.

0:05:25 > 0:05:30I suppose my father was very interested in recording anyway in all kinds of observations.

0:05:30 > 0:05:34His diary was kept for something like 60 years.

0:05:36 > 0:05:41You know, it's extremely interesting now to read them, of course,

0:05:41 > 0:05:46because he said, "I saw a beautiful mouse tonight, absolutely perfect,

0:05:46 > 0:05:49"lovely tail, and I had a really good view of it."

0:05:49 > 0:05:56And that's what we were doing, was watching for dormice behaving naturally in the wild.

0:05:56 > 0:06:03Through their dedicated dormice watching, the amateur naturalists made a significant discovery.

0:06:03 > 0:06:07"Late October, I happened to walk under a large hazel bush

0:06:07 > 0:06:09"about 100 yards from our house,

0:06:09 > 0:06:14"and found that other creatures besides squirrels had shown interest in the nuts.

0:06:14 > 0:06:20"I picked up over 30 shells from which the kernels had been extracted through a hole at one side.

0:06:20 > 0:06:24"This could not possibly be the work of squirrels.

0:06:24 > 0:06:28"It appeared even at a glance to be the work of mice."

0:06:28 > 0:06:31They were very good carpenters, dormice, I always remember that.

0:06:31 > 0:06:37And they have a tiny chiselling effect on the edge of the hole.

0:06:37 > 0:06:40The discovery of these distinctive calling cards

0:06:40 > 0:06:44mean that you no longer have to see dormice to know they're there.

0:06:45 > 0:06:48So Elaine was asked by the Mammal Society to do a survey.

0:06:48 > 0:06:54For the first time, it was possible to produce a dormouse map of Britain.

0:06:54 > 0:06:57The survey was, when you look back on it, was great fun.

0:06:57 > 0:07:00It was hard work as well, but...

0:07:00 > 0:07:04Jumping in the bramble bushes to look for nuts!

0:07:04 > 0:07:07Today Tom is building on that knowledge.

0:07:07 > 0:07:10Ah, you can see its front feet quite well...

0:07:10 > 0:07:14Ah, it's on the move, I'm gonna have a job to sex this one, I think.

0:07:14 > 0:07:15The total weight now is 55.3...

0:07:17 > 0:07:21So that's a gram or so more than that female.

0:07:21 > 0:07:26All this weighing, sexing and measuring goes to the People's Trust For Endangered Animals.

0:07:26 > 0:07:29Sadly, dormice are on their list.

0:07:29 > 0:07:33It's an amazing creature that has been in this country for

0:07:33 > 0:07:41thousands of years, and up till, well, perhaps maybe...only about

0:07:41 > 0:07:4450 years ago, we started to get to grips

0:07:44 > 0:07:48with how this animal behaved, and what it was doing,

0:07:48 > 0:07:52and because we now have more data about dormice

0:07:52 > 0:07:57than maybe any other small mammal in this country,

0:07:57 > 0:07:59any effects of global warming might first

0:07:59 > 0:08:04appear in a creature like this, which has a completely different strategy from all the others.

0:08:04 > 0:08:10It's vital that amateurs like these keep an eye on animals like dormice,

0:08:10 > 0:08:13and it's lucky their sleeping habits allow us to see them easily.

0:08:13 > 0:08:18But hidden in a wooded valley in Gloucestershire, other mammals

0:08:18 > 0:08:22have chosen a less accessible, but much grander place for a bedroom.

0:08:25 > 0:08:28Woodchester estate was bought by William Leigh in 1845.

0:08:28 > 0:08:34He commissioned architects to build a forbidding gothic mansion, but the house was never finished.

0:08:34 > 0:08:38It was mysteriously abandoned 23 years later.

0:08:44 > 0:08:49Visitors have reported sightings of a headless horseman, and even a floating coffin!

0:08:52 > 0:08:57No wonder it has the reputation of being one of the most haunted houses in Britain!

0:08:59 > 0:09:02And up in the ancient rafters are some residents who certainly add

0:09:02 > 0:09:07a frisson to the place - but to see them, you have to wait until after dark.

0:09:11 > 0:09:13SQUEAKING

0:09:17 > 0:09:21The horseshoe bats are famous for their noses.

0:09:21 > 0:09:26It just blasts its echo-location sounds through its nostrils

0:09:26 > 0:09:30into what is like a parabolic reflector, it's like a torch beam.

0:09:30 > 0:09:34Then they get these beautifully focused beams of ultrasound,

0:09:34 > 0:09:39which make them incredibly good at distinguishing fine detail.

0:09:41 > 0:09:44They can discriminate between different types of insects

0:09:44 > 0:09:48while there are flying, in ways that are very difficult to understand.

0:09:48 > 0:09:53Despite being the largest and longest-living bat in Britain,

0:09:53 > 0:09:58its numbers have plummeted by 90% over the last 100 years,

0:09:58 > 0:10:01making it one of our rarest species.

0:10:01 > 0:10:05But this is the first file I had to do my project.

0:10:05 > 0:10:09We did basic descriptions of the habitat...

0:10:09 > 0:10:12Roger Ransome was the ultimate schoolboy naturalist.

0:10:12 > 0:10:17I started working on bats in 1956 as part of a school project.

0:10:19 > 0:10:22I felt that this was a really good area to get into

0:10:22 > 0:10:25because there was very little known about the natural history of bats.

0:10:25 > 0:10:27It was known that bats live a long time.

0:10:27 > 0:10:31They actually can live up to 40 years.

0:10:31 > 0:10:35I got the art prize for Cheltenham Grammar School in the first year.

0:10:35 > 0:10:39We had heard that there were lots of bats coming out of Woodchester mansion.

0:10:39 > 0:10:45And we made an attempt to get in while we were at school.

0:10:45 > 0:10:51The man who had the lease on the mansion wasn't too keen on sixth-formers wandering around,

0:10:51 > 0:11:00and it wasn't until 1959 that I persuaded him that, really, I was an upright and honest person...

0:11:02 > 0:11:07Roger's schoolboy persistence has continued for 51 years.

0:11:07 > 0:11:11His study of the bats in Woodchester has been going on longer

0:11:11 > 0:11:14than any study of any mammal in the whole world!

0:11:14 > 0:11:21When I started, I was doing all the basic biometric measurements that I still do today.

0:11:21 > 0:11:26We're now through something like 10 generations, it's just keeping it

0:11:26 > 0:11:30going consistently for that period of time which makes it become valuable.

0:11:35 > 0:11:38The computer says 107 bats went out.

0:11:41 > 0:11:44Nowadays, the computer is the saving grace.

0:11:44 > 0:11:46I could not process data without it.

0:11:47 > 0:11:51That's where Michael, my grandson, comes in, cos he's my IT adviser.

0:11:54 > 0:11:56Are yours coming out, Gemma?

0:11:56 > 0:11:58We've only got three out so far.

0:11:58 > 0:12:04Every week, Roger and his army of volunteers use a mass of technology to monitor the bats.

0:12:04 > 0:12:12Ted and Gemma are...have swung the cameras around, so that they are counting the bats flying out to feed.

0:12:12 > 0:12:17If the bats go out when it's very, very bright, we know they're diet-stressed.

0:12:17 > 0:12:22If they go out when it's very dark, we know they've got plenty to eat, and they're fine.

0:12:22 > 0:12:24This one...

0:12:24 > 0:12:27Well, this is to look for

0:12:27 > 0:12:33behaviour patterns between animals that we know are related to each other.

0:12:33 > 0:12:38And the associations seem to be mainly between the females.

0:12:38 > 0:12:41This is a female-dominated society,

0:12:41 > 0:12:46er, and what we have is a series of matrilines,

0:12:46 > 0:12:51lines of bats that go back to a single female.

0:12:52 > 0:12:59And all together, we've got something like 15-17 matrilines in the colony, so it's a large number.

0:12:59 > 0:13:02The more I find out, the more there is to find out.

0:13:02 > 0:13:05The complexity of this animal is just utterly amazing.

0:13:05 > 0:13:11It's been around 40 million years, and, er, we're pretty recent arrivals on the scene.

0:13:11 > 0:13:16They have an incredibly complex social organisation,

0:13:16 > 0:13:20vocal communications, which we're only just beginning to understand.

0:13:20 > 0:13:22Right, so, I'm going through this hole...

0:13:22 > 0:13:26But it's not all hi-tech, and you do need to stay in shape.

0:13:28 > 0:13:31Once the bats have left the roost, Roger can get in.

0:13:31 > 0:13:36Well, how else can you collect your weekly bat droppings?

0:13:36 > 0:13:41This yellow sheet is beneath the attic space that we were looking at.

0:13:42 > 0:13:44I'm gonna take them back to my house,

0:13:44 > 0:13:50dry them all out, and then we'll treat them in solutions,

0:13:50 > 0:13:56and we're left with the skeletons of the insects, which we can recognise under the microscope.

0:13:57 > 0:14:00And all jolly good fun.

0:14:00 > 0:14:04We do it week in, week out, and we see how the diet changes.

0:14:04 > 0:14:07That's quite a lot, really, for one week.

0:14:07 > 0:14:09They're feeding well at the moment.

0:14:09 > 0:14:14The other thing we have to do is to check the state of our cameras.

0:14:14 > 0:14:17Roger has contributed to 34 scientific papers.

0:14:17 > 0:14:21And in 2002, he co-wrote the European Action Plan,

0:14:21 > 0:14:26which gives better protection to greater horseshoe bats.

0:14:26 > 0:14:31They do say scientists have their most productive work by the time they are 30 or 40.

0:14:31 > 0:14:34I think that depends on the type of work you're doing.

0:14:34 > 0:14:39To make generalisations about what's going on, you do need long periods of time.

0:14:39 > 0:14:42When you've got a bat that lives 30 years,

0:14:42 > 0:14:48then really you should do 60 years to be sure that the first 30 years is the same as the second 30!

0:14:48 > 0:14:52But will Roger ever feel like he's done enough?

0:14:52 > 0:14:57First of all, I thought when you got to 40, you were past doing these sorts of things,

0:14:57 > 0:15:00then I thought, "Well, perhaps when you get to 50, you're past it."

0:15:00 > 0:15:06And at the moment my wife thinks that it's high time that I hung up my boots.

0:15:06 > 0:15:11To be fair to her, it will have to come one day.

0:15:13 > 0:15:16Determination is the watchword for mammal lovers.

0:15:16 > 0:15:19Their dedication spans decades.

0:15:19 > 0:15:23These long-term studies often provide the information others need

0:15:23 > 0:15:25when planning our modern world.

0:15:25 > 0:15:29Thank goodness amateur naturalists have the stamina and commitment

0:15:29 > 0:15:31to keep going.

0:15:31 > 0:15:35I want to be someone who knows as much as possible

0:15:35 > 0:15:37about European brown hares.

0:15:38 > 0:15:41And I'd much rather be here even though it's raining

0:15:41 > 0:15:43than sitting in an office.

0:15:43 > 0:15:46I'm not just standing here getting wet.

0:15:46 > 0:15:49I'm pursuing something I really want to do.

0:15:52 > 0:15:55This pretty suburban garden in Hertfordshire

0:15:55 > 0:15:58just 15 miles from London is surprisingly close

0:15:58 > 0:16:02to where Gill Turner likes to spend most of her time.

0:16:12 > 0:16:14It's 5.30 in the morning

0:16:14 > 0:16:16and Gill is already on her way.

0:16:16 > 0:16:20She is one of only a handful of amateur naturalists in the UK

0:16:20 > 0:16:22studying the secretive brown hare.

0:16:22 > 0:16:25I prefer to come out in the early morning

0:16:25 > 0:16:27because the light's better then

0:16:27 > 0:16:32and there's more chance of seeing them still grazing from the night before.

0:16:32 > 0:16:35I've been aware of the hares in my area for many years.

0:16:35 > 0:16:40I started to wonder what they were up to basically

0:16:40 > 0:16:43and try and understand why their numbers were dwindling.

0:16:48 > 0:16:51It was the Romans who introduced hares to this country

0:16:51 > 0:16:53about 2,000 years ago.

0:16:53 > 0:16:56They were once widespread throughout Britain

0:16:56 > 0:16:59but have now disappeared from many places.

0:17:00 > 0:17:02When you see something

0:17:02 > 0:17:05running at...that looks like a very large rabbit

0:17:05 > 0:17:10running at 45mph across in front of you,

0:17:10 > 0:17:13you can't help but think Britain's fastest mammal,

0:17:13 > 0:17:15you know, that's incredible.

0:17:17 > 0:17:22For 15 years, Gill has immersed herself in the life of hares,

0:17:22 > 0:17:26honing her field skills, so she can get as close as possible.

0:17:26 > 0:17:29We're just coming up to the meadow where I know the hares are

0:17:29 > 0:17:36so if possible could we be quiet and creep over there without making too much noise?

0:17:36 > 0:17:38(Thank you.)

0:17:45 > 0:17:48Keep this way.

0:17:51 > 0:17:54Can you see down there?

0:17:55 > 0:17:58Can you see that brown...?

0:17:58 > 0:18:00There's two hares down there...

0:18:00 > 0:18:02together.

0:18:04 > 0:18:06Did you see that at all? Oh, dear.

0:18:06 > 0:18:12Sometimes it takes the eye of a true amateur to spot what's hiding in the field.

0:18:20 > 0:18:22Can you see them?

0:18:22 > 0:18:24I can see two hares.

0:18:25 > 0:18:27They're both grazing.

0:18:28 > 0:18:32I think they're siblings, part of a group of three.

0:18:32 > 0:18:35I suppose there's a possibility that...

0:18:36 > 0:18:38..as they get older they'll attract...

0:18:40 > 0:18:42..bucks.

0:18:42 > 0:18:45Shall we try and get a bit closer? OK.

0:18:47 > 0:18:49Probably in this length of grass,

0:18:49 > 0:18:52the first the first thing you'll see are the ears.

0:18:59 > 0:19:03When I'm photographing them, and if they come really close to me,

0:19:03 > 0:19:06I have a job to keep my camera steady because it's so exciting.

0:19:06 > 0:19:10Each time I think, "Oh, I've obviously got a brilliant photograph this time."

0:19:10 > 0:19:12SHE LAUGHS

0:19:15 > 0:19:16CAMERA CLICKS

0:19:16 > 0:19:20Gill's photos help her to understand behaviour

0:19:20 > 0:19:22and identify who's who.

0:19:22 > 0:19:24If it's a buck and a doe,

0:19:24 > 0:19:27it's possible that they'll completely ignore me

0:19:27 > 0:19:30because they're fully occupied in what they're doing.

0:19:30 > 0:19:32And with youngsters,

0:19:32 > 0:19:35they're so oblivious,

0:19:35 > 0:19:38especially if they haven't had any contact with humans anyway

0:19:38 > 0:19:40but they're easy to photograph.

0:19:42 > 0:19:46I think they're animals that not many people know much about.

0:19:47 > 0:19:51And there's so much more to a hare than just looking like a big rabbit,

0:19:51 > 0:19:52you know.

0:19:52 > 0:19:54Their life is complex, it really is.

0:19:59 > 0:20:04These beautiful and entrancing animals have declined dramatically over the last 100 years,

0:20:04 > 0:20:08so more information is needed to help them survive the modern world.

0:20:08 > 0:20:12Gill's observations go to her local records office

0:20:12 > 0:20:16and it's vital studies like these continue through generations.

0:20:20 > 0:20:22My mentor was Tony Holly.

0:20:23 > 0:20:27He lived in Somerset and he was well-known in his field.

0:20:27 > 0:20:29I wrote to him

0:20:29 > 0:20:31and he called me

0:20:31 > 0:20:33almost straight away.

0:20:33 > 0:20:37And I was overwhelmed, actually, it was wonderful

0:20:37 > 0:20:43that somebody as important as him should take an interest in somebody

0:20:43 > 0:20:45who hadn't got any scientific background.

0:20:45 > 0:20:48It was great. He really encouraged me.

0:20:49 > 0:20:52When he died, I felt very much alone in my work

0:20:52 > 0:20:57because I'd had somebody to report to.

0:21:00 > 0:21:04Sometimes when I'm on my own and I'm wet and I'm cold...

0:21:05 > 0:21:08..and I haven't seen a hare,

0:21:08 > 0:21:12I think to myself, "Why am I doing this? Does anybody really care?"

0:21:12 > 0:21:18And I've got friends who think I'm mad, but I like to think that I've got enough field experience

0:21:18 > 0:21:22and I've spent enough time watching the hares without interfering with them,

0:21:22 > 0:21:25that I have gained some knowledge

0:21:25 > 0:21:29and possibly seen things that other people don't see.

0:21:29 > 0:21:34Hares, like most mammals, find themselves at the rough end of human development.

0:21:34 > 0:21:38Intensive agriculture, housing, industrialisation

0:21:38 > 0:21:40and roads all take their toll.

0:21:42 > 0:21:47One mammal in particular was pushed right to the brink of extinction.

0:21:47 > 0:21:48Rare, elusive...

0:21:48 > 0:21:49nocturnal...

0:21:49 > 0:21:55No wonder James Williams in Somerset has to make do with decidedly unglamorous evidence.

0:21:58 > 0:22:01We're going to go to the otter loo,

0:22:01 > 0:22:03or what I call the otter loo,

0:22:03 > 0:22:06which is a pile of stones in the stream,

0:22:06 > 0:22:09which I check every day.

0:22:09 > 0:22:13They leave a nice juicy heap of pooh, if I'm lucky, a nice spraint.

0:22:13 > 0:22:19That means that I can tell the frequency with which this stream is used by otters

0:22:19 > 0:22:23which gives some indication of the level of population.

0:22:27 > 0:22:29It's very difficult to see an otter.

0:22:29 > 0:22:32I've never seen one here.

0:22:32 > 0:22:37If I wanted to see an otter at the otter loo, I'd have to sit on the bridge for half the night.

0:22:37 > 0:22:40So this is the otter loo.

0:22:40 > 0:22:42This is the side stream of the River Tone.

0:22:42 > 0:22:43Oh, my goodness!

0:22:43 > 0:22:48They must have known you were coming because that set of footmarks there,

0:22:48 > 0:22:50that's otter padding going upstream.

0:22:50 > 0:22:52I washed that sand yesterday

0:22:52 > 0:22:55and there wasn't any otter padding at bedtime last night,

0:22:55 > 0:22:56so I'm very pleased.

0:22:56 > 0:22:59On my little stream. Excellent.

0:23:07 > 0:23:11At the moment I'm quite excited because I think I've got a bitch and cub

0:23:11 > 0:23:14and so I'm checking to see whether this is one woozle or two weasels,

0:23:14 > 0:23:16or whatever Christopher Robin said.

0:23:17 > 0:23:22But I think an otter would go one, two and be off

0:23:22 > 0:23:26and the fact that we've got more, I'm hoping that that is the cub

0:23:26 > 0:23:28and that's the mother there.

0:23:28 > 0:23:30And this spraint...

0:23:30 > 0:23:32That's a very typical otter spraint,

0:23:32 > 0:23:35a sort of black shapeless, crinkly object...

0:23:36 > 0:23:39..which it gives me great pleasure to see.

0:23:39 > 0:23:43Otters signal to other otters by leaving their pooh on a rock

0:23:43 > 0:23:47as a smelly warning that this bit of river is already occupied.

0:23:48 > 0:23:50Trespassers are not welcome.

0:23:54 > 0:23:57Why otters and not any other species?

0:23:57 > 0:24:00Because all other species are inferior.

0:24:01 > 0:24:04Rabbits are worse at being rabbits

0:24:04 > 0:24:06and, er...

0:24:06 > 0:24:09any fool can be a guinea pig or a fox.

0:24:09 > 0:24:11But it takes an expert to be an otter.

0:24:11 > 0:24:15They really are in control of themselves, in control of their environment,

0:24:15 > 0:24:19they're just a very exceptional grade of animal.

0:24:21 > 0:24:22HUNTING HORN IS BLOWN

0:24:24 > 0:24:28James's admiration came out of a long but unusual relationship

0:24:28 > 0:24:30with otters.

0:24:30 > 0:24:33We were totally involved in otter hunting.

0:24:33 > 0:24:35Father was master of the otter hounds

0:24:35 > 0:24:37and so was I eventually.

0:24:37 > 0:24:41In those days, there was no form of conservation

0:24:41 > 0:24:44other than the hunts, really,

0:24:44 > 0:24:48who paid money to the farmers where otters were found

0:24:48 > 0:24:54who gave Christmas presents to gamekeepers to not trap the otters to destruction,

0:24:54 > 0:24:58so the hunters were the conservationists of the day.

0:24:58 > 0:25:04When the decline came and pesticides started to harm the otters,

0:25:04 > 0:25:06it was the hunts that drew attention to this

0:25:06 > 0:25:11and the hunts that provided most of the data which enabled people to get to grips with it.

0:25:12 > 0:25:14I do think since the 1940s

0:25:14 > 0:25:16I have accumulated

0:25:16 > 0:25:18a body of experience and knowledge

0:25:18 > 0:25:20which ought to be recorded

0:25:20 > 0:25:21and passed on

0:25:21 > 0:25:24because the rivers are not in a totally healthy state now.

0:25:24 > 0:25:26They're cleaner to the eye,

0:25:26 > 0:25:29they don't smell as much and if we want to have some wildlife

0:25:29 > 0:25:32we need a new generation of people to come along.

0:25:32 > 0:25:36James's passion for otters led him to run the Somerset Otter Group,

0:25:36 > 0:25:39an 80-strong band of amateur naturalists

0:25:39 > 0:25:43who routinely check a particular stretch of river.

0:25:43 > 0:25:44By putting all the data together,

0:25:44 > 0:25:47he gets a unique insight into the local otters.

0:25:49 > 0:25:51We gradually build up a picture of evidence,

0:25:51 > 0:25:55a bit like lots of little creatures build up the Great Barrier Reef.

0:25:55 > 0:25:58Little bits, little bits, little bits all add together.

0:25:58 > 0:26:01It may not seem as if you're making a lot of difference

0:26:01 > 0:26:05but I have had one or two things which I think were of importance.

0:26:05 > 0:26:10We picked up a dead otter and sent it away for analysis

0:26:10 > 0:26:13and it turned out to hold a world record

0:26:13 > 0:26:18of dieldrin at a time about six, seven years after dieldrin had been banned

0:26:18 > 0:26:22and it was traced back with the help of some experts

0:26:22 > 0:26:24to a government cloth factory

0:26:24 > 0:26:26where they were using dieldrin.

0:26:26 > 0:26:29We found that. The public do help.

0:26:29 > 0:26:31The fishermen do help.

0:26:31 > 0:26:32Farmers help.

0:26:32 > 0:26:35Birdwatchers are a very great source of information.

0:26:35 > 0:26:39We put it all together and gradually we're getting most of the jigsaw.

0:26:39 > 0:26:42In some ways, it's a thankless passion,

0:26:42 > 0:26:46not least because James never sees an otter on his land.

0:26:47 > 0:26:49Does it take dedication?

0:26:49 > 0:26:53I suppose it does take dedication to study a species that you never see.

0:26:54 > 0:26:59This nomadic creature comes mysteriously through my garden at night.

0:27:00 > 0:27:02It doesn't give twopence about us.

0:27:02 > 0:27:06It's just going through the river as it has done for hundreds of years.

0:27:06 > 0:27:08Our presence is nothing to the otter,

0:27:08 > 0:27:11but the otter's presence is everything to me.

0:27:11 > 0:27:16Otters, like all our animals, need people who care deeply about them.

0:27:16 > 0:27:19Our British wildlife needs a healthy environment

0:27:19 > 0:27:22and it doesn't take much to upset the balance.

0:27:23 > 0:27:27Otters live right on the cusp of what it is possible for them to live.

0:27:27 > 0:27:30If the otters go, it means the streams are in a mess.

0:27:30 > 0:27:33It means the fish are in a mess. It means the dragonflies are in a mess.

0:27:33 > 0:27:36It means that kingfisher that just came past us won't come past.

0:27:36 > 0:27:40If the otters can't hack it, nobody can hack it.

0:27:40 > 0:27:42We've got to have clean rivers.

0:27:42 > 0:27:45The hallmark of the amateur British mammal lover

0:27:45 > 0:27:47is dedication -

0:27:47 > 0:27:48and thank goodness.

0:27:48 > 0:27:52Without them, many of our mammals might quietly disappear

0:27:52 > 0:27:54without most of us noticing.

0:27:55 > 0:27:58To know more about the skills needed to be a mammal watcher,

0:27:58 > 0:28:01log on to our website...

0:28:06 > 0:28:08Next time, on Born To Be Wild,

0:28:08 > 0:28:11passions run high for the small and understated.

0:28:11 > 0:28:13They're about two millimetres across.

0:28:13 > 0:28:15HE LAUGHS

0:28:15 > 0:28:16The rare and elusive...

0:28:16 > 0:28:18There's not enough...

0:28:18 > 0:28:20The less than glamorous but fascinating...

0:28:20 > 0:28:22Eugh!

0:28:22 > 0:28:24And the minibeasts that keep our rivers alive.

0:28:24 > 0:28:26- That's it.- What's he doing in there?!

0:28:26 > 0:28:31Join our amateur naturalists as they watch over The bugs Of Britain.

0:28:39 > 0:28:41Subtitles by Red Bee Media Ltd

0:28:41 > 0:28:43E-mail subtitling@bbc.co.uk