How do you count all the polar bears in the Arctic? | Rod Downie | TEDxBrighton
URL: https://www.youtube.com/watch?v=JvSgTk8DHfE Video ID: JvSgTk8DHfE ============================================================ [Music] [Applause] thanks Anson it's the sixth of April 2016 the temperature is about minus 37 degrees and I've just been dropped off with a colleague on the sea ice that's frozen ocean up in the Canadian Arctic my colleagues name is Mike and he is a laboratory technician he works for the government of nunavut in Canada and we've just flown in from a small indigenous Inuit community called resolute Bay it's about 100 miles to the northeast of us so it's remote and I remember thinking at that time that perhaps the closest other person to us might be commander Tim Peake as he passed overhead in the international space station but about a hundred metres away from me there's a large adult male polar bear and he weighs about seven times my body weight he has 42 razor-sharp teeth and he can cover that hundred meter distance over that terrain faster than Usain Bolt and I figure there are probably two things going through his mind at that time it's early April he's just come out of the very lean winter months and he needs to gain body mass fast and he's looking at me straight in the eyes and he is thinking food but luckily for me he's also looking up above our heads to where our helicopter is circling and he's thinking fear so those might have been the two things that were going through his mind but I remember very clearly there were two things going through my mind at that time and the first and perhaps the most important of those was just how lucky I am to be working for WWF the most exciting and the most relevant conservation organization in the Arctic an organization which is absolutely driven by science and inspired by nature the second thing that was going through my mind well it was more of a realization really that's actually I didn't need to run as fast as Usain Bolt I just needed to run faster than my colleague Mike so the reason why I'm on the ice is because there are still some very fundamental questions that we need to answer in polar bear science and we need the answers to those questions to inform our conservation how many polar bears are there in the wild how are they reacting to the very dramatic rate of change that we're seeing in the Arctic today and can we predict how they might respond in a climate altered future and it still absolutely astonishes me that even today despite polar bears being the face of climate change we just don't know with any degree of certainty how many polar bears there are on our planet the best estimate suggests that there are between 22 to 31,000 hold on 22 to 31,000 that is an enormous range of uncertainty what we do know about polar bears is that they need sea ice they depend upon sea ice they have evolved over millennia to the on and around and even swim underneath the sea ice but the Arctic is ground zero for climate change and sea ice is in rapid decline and we know this with absolute scientific certainty because there are satellites such as cryosat-2 which are passing over the Arctic every day taking daily photographic records of sea ice extent and models predicts that the Arctic could be virtually free of sea ice during the summer months within a generation by 2040 or perhaps sooner so let's come back down to earth and back to our mother polar bear with her cub on the diminishing sea ice what sort of future does this signal for these icons on ice well it's predicted that the population of polar bears could drop by about 30% by the middle of this century so in just over 30 years from now we may have lost a third of all the polar bears on our planet and that is predicted to happen on our watch now it's clear that in order to protect polar bears into the future we need to better understand them today but there are huge challenges associated even with just counting polar bears in the Arctic the Arctic is vast it's remote it's unforgiving it's a very difficult place for scientists to work it's a very expensive place for scientists to work and polar bears just blend very nicely into their icy background so just how do you count all the polar bears in the Arctic well I would like to give you three examples to share with you of how we have built partnerships to stimulate innovation and creativity in order to provide Solutions to try and answer that question for my first example I'd like to introduce you to a new way of counting animals it's called genetic mark-recapture so in April 2016 I was invited by the government of nunavut in Canada to work alongside Inuit partners and alongside Mike to undertake a population census of a place called McClintock Channel it's one of the smallest subpopulations there are about 280 bears spread over an area of 300,000 square kilometers so roughly the size of the UK and it was our job to try and find them all so we flew these grids by helicopter at an altitude of 400 feet and every time we saw a polar bear we would take a skin biopsy from it using a dart identical to this one it's completely harmless to the polar bear it's undertaken under very strict protocols so you fire the dart at the Bears haunch and it grabs a small 5 millimetre sample of skin and hair and fat and then drops onto the ice and then one of us had the the lucky job of having to jump out of the airplane after the a at the helicopter and go and retrieve that darts with a very angry polar bear still in the near vicinity but this incredibly valuable sample of skin and hair and fat is then sent off to a laboratory for DNA analysis and that gives us a unique genetic fingerprint for that particular bear and so over the course of the survey you can add up all of these genetic fingerprints and that gives you a really accurate estimate of the population size this innovation has the capacity to absolutely transform understanding of polar bear populations and trends and dynamics right across the Arctic for my second example well this is the remarkable story of just what you can learn from a footprint in the snow so in 2014 my colleagues from WWF and from the Norwegian polar Institute collected samples of snow just from footprints polar bear footprints in the snow up in Svalbard in the Norwegian Arctic and we sent those samples off to a French company called spy Jen to see if they could extract environmental DNA just from the melted snow and spy Jen called us up and said yes we have absolutely isolated genetic markers of polar bears that's clear but we've actually picked up markers from three different species is that possible so we went back to the guys who'd collected the samples in the field and asked what they thought and they said you know come to think of it when we collected that sample that polar bear had just been feeding on a ringed seal and a gull had flown down to scavenge on the carcass an incredibly spy Jen could reconstruct this entire story as it unfolded just from a footprint in the snow this is really exciting innovation this is science just in a teaspoonful of snow for my third and final example is about attaching thermal infrared cameras to airplanes so let's focus on the chukchi sea this covers an area of about 600,000 square kilometres it connects Eastern Russia to Alaska and we had no idea how many polar bears roam the Chukchi Sea so in May 2016 we partnered with us and Russian scientific research institutes and we flew these lines at an altitude of a thousand feet using high-resolution aerial survey cameras to undertake a population census of seals and polar bears but we also attach these thermal infrared cameras to those aircraft and I thought it would be fun just to show you some of the outputs from that expedition so here you see one of the high-resolution images from the expedition can you spot the polar bear put your hands up if you can see the polar bear in this picture where are we looking top left bottom right somewhere around the middle I see a small number of hands but the truth is it's virtually impossible to pick out the polar bear from that picture however this picture was taken from exactly the same airplane at the same time the same location using the thermal infrared camera now put up your hands if you can see the polar bear in that picture so most of your hands have gone up I expect you're talking about this bright white dot down here well it's certainly a very interesting signal but actually I can't identify that as a polar bear so let's go back to the high-resolution photograph but zoom in and yes that is very clearly another data point to add to our population graph that is quite clearly a polar bear so congratulations everyone you have just counted your first polar bear and you have just joined a very elite international community of polar bear scientists ladies and gentlemen I spoke in my introduction about coming face-to-face with a large adult male polar bear but if there's one thing that terrifies me more than coming face-to-face with a polar bear it's the thought that my son Callum who is just four years old might not come face-to-face with polar bears on Arctic sea ice when he is my age there are massive challenges ahead for Arctic wildlife and for Arctic people but by tackling climate change now we can still stabilize the Arctic and by better understanding polar bears now we can still plan for change and we can still charter future for these incredible icons on ice and I hope that when you leave the room at the end of today that you will continue like me to be driven by science and inspired by nature thank you very much [Applause]