Portland decided to snow the first day of SICB in the morning, which turned into freezing rain by the time of the plenary talk in the evening.
The opening talk was "The biology of big" by Terrie Williams. Triggered to be a biologist by Life magazine cover on "The Great Cats of Africa" in January 1967. Gave a shout out to all the great mentors she had (all men).
Started with American mink, and she was terrified of them. Moved to swimming otters, then seals, then dolphins, then killer whales, all to figure out their oxygen consumption and metabolism.
Everything she measured was above the Kleiber curve for terrestrial mammals oxygen consumption. Reason being that carnivore is expensive. What was driving the high cost for these animals?
Showed pictures of a polar bear on a treadmill, Tasul, who is from the Portland Zoo. Had video of what bears do to treadmills, who want to tear apart everything. First day of turning the treadmill on. Bear was walking in three inch steps to "Gonna Fly Now" from Rocky.
Cost of swimming, running, and flying is similar for all mammals. That was a surprise. A swimming seal has the same cost of transport as a running dog of same size. Used analogy that all of these animals are using the same engine. You have to be concerned about the net versus total energetic cost.
"The entire planet was being driven by how much these big, hungry, carnivorous animals were eating." The top predators have a profound impact on the ecosystem.
Example: where did all the marine mammals in the Aleutians go? Looked at Stellar sea lions to figure this out, and the numbers kept going down. Orcas ate ten times the amount of a large shark. Could they be responsible for the domino effect of large marine mammals disappearing? Their metabolic rate was about three times that of other marine and terrestrial carnivores.
The caloric content need to stay alive is enormous: 200-300,000 kcal a day. This means 5-7 otters a day. Keeping a single pod alive could account for all the missing sea otters.
The whaling industry took out the key top, high energy food for orcas. So they ate down the food chain - at least that was the hypothesis. How could foraging costs be assessed in the wild? Technology with accelerometers and cameras and such made it possible.
With this technology, they learned marine mammals cheat, and do as little as possible. Energetic costs are also about defending resources like air holes. Looked for the same idea of breathing holes in narwhals. Narwhals are pure endurance animals - they couldn't swim fast if they wanted to. "I didn't believe narwhals existed, so I didn't know how we would measure its heart rate."
Narwhals love in a "landscape of fear." They are very sensitive to disturbance, which is mainly humans. Their heart rate drops down to 3-4 beats a minute. "This is like paralysis for an animal."
The changes in ice are bad for the narwhals, because it's not only the ice thinning, but piling up.
After 50 years, finally got to study lions in Africa. "This was truly a dream come true." The question was chat are the impact of lions on the local prey, and can humans live with lions?
Accelerometers are so good now you can see each paw hit the ground in the records. Can track an entire kill from an accelerometer trace, and get the size of the kill from the remains.
So can we predict lion predation events to prevent human/lion conflict?
Worked with a great tracker to find a lion, Kichaka. "I did something very unscientific. ... I just had to touch every inch of this lion." They now have 7 males, 19 females and young. You can follow them on africanlions.org. They are trying to see which males are pairing together.
They can figure out whether stops are rest points or feeding points to prevent retaliatory killing. Lots of time spent talking to herdsmen to figure out why, are kills lions or hyenas, etc. Sometimes the herdsmen are at fault for not bringing cattle in.
The bottom line: measured costs of hunting are about two and a half times expected from modeling. It's costly to be a big predator, because of different terrain, etc.
Kichaka died on Christmas. The collar will probably tell them what happened to the lion. But after 50 years, it's heartbreaking to see this happen to an animal. These things are happening every day, they just happened to record it.
There is also very little money for large animals. "It just isn't transformative." The highly endangered Amur leopard has 25 papers over 50 years. "How can we save them when we don't know how they work?" Her work was funded a lot through NSF Polar - which ended up on the #3 on the congressional wastebook. She shot back with a LA Times editorial, which mostly ended it. Except she got a FOIA from Lamarr Smith.
So why bother? You have to dig deep and go back to where you started. "tHere is nothing more rewarding and exciting than exploring nature."
This morning, she learned that one of her lions, Davey, just had cubs. "The ones saved."
She's asked by the media all the time, "What good is this?" Plays a video about the race against extinction, showing many examples of her research used in protecting endangered mammals. 1980s , start. 1990s, climate change. 2000s, age of endangered mammals. 2010s, never say die!
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