Nov 12, 2020
This week we're surfing the green wave! Seasonal mule deer migration is based on food availability. Deer move across the landscape to maximize their access to high-quality food resources. This week we're joined by migration ecologist Ellen Aikens of the Monteith Shop to learn more about Wyoming's mule deer populations and how they're challenged by drought, climate change, and energy development.
3:00 - Artemis's first guest to connect from overseas! Plus, moving to Germany during the pandemic
6:30 - Animal research: A generally rewarding endeavor with LOTS of challenges
8:00 A new scientist asks her peers/mentors, What's one of the most important fields to be savvy in? "GIS/remote sensing" comes up again and again
11:00 GPS collars let us see where an individual animal is going, year after year -- it's a bonafide jackpot of data. This field is called "movement ecology"
12:30 Marcia's sage advice: "Do what you enjoy doing until you don't enjoy doing it anymore. Then go do something else."
13:30 Sampling the field April-August to survey which plants are available and when. Documenting the seasonal change from green to brown was revelatory! Plus, KNOWING the place.
17:00 Dynamics in plant growth and seasonal transition influence how animals move
18:00 To study mule deer you need to become versed in the world they live in
20:00 "The green wave" - this idea that for deer and other species, young/emergent plant species are the most nutritious growth. That stage is staggered across an elevational gradient -- and this is the 'green wave' -- moving to find that nutritious feed
22:00 Most mule deer move from a low-elevation winter range to a higher elevation spring/summer range. This is colloquially called 'surfing the green wave'
24:00 Migration isn't a continuous line from Point A to Point B. Mule deer spend about 90% of their time on migration at stopover sites, foraging and eating
27:00 What makes a good stopover? It totally depends. Elevation plays a big role. They're generally places that are more lush than the surrounding area.
30:00 Fall migration: A combination of fleeing cold/snow, plus finding the lushest feed given the season... the "residual greenness"
33:00 Drought has an effect on how well mule deer can surf the green wave, which is shorter; Energy development also affects that migration
35:00 Mule deer in the West have high fidelity to their migration routes
38:00 Mule deer DO move through energy development sites... but they're not able to use those areas to the degree they would if there was no resource development there
39:00 A high-quality study would collect data BEFORE an energy project, DURING it, and AFTER reclamation
45:00 Being migratory is key for mule deer in the Wyoming Range. There ARE resident deer populations, but it's a small fraction (<5%) of the whole. Surfing the green wave results in access to higher quality feed, which improves deer body condition and reproductive success
47:00 Drought/climate change/fire/invasive species stand to alter how the green wave moves across the landscape
55:00 Mapping migrations is crucial to understanding how they're impacted by development and other threats
58:00 Wyoming's governor signed an executive order that acknowledged migration corridors. Good science DOES inform policy.
1:02 Wyoming Migration Initiative has a great coffee table book, "Wild Migration: Atlas of Wyoming Ungulates"
1:07 Animal movements stand to change as green-up patterns change (elk are also green-wave surfers)
1:10 Norway, Italy, Germany, France... all these countries have good data on deer migration and changing green-up patterns (Want to nerd out even more? EuroDeer is a collaborative group of ungulate ecologists with great data. Check them out.)
1:12 Are there places where green-wave migration has stopped because of barriers we've inadvertently put up? Yes. We alter animal behavior all the time.
1:16 Reproductive behaviors are finely tuned to greenup-related movement
1:21 Find out more about the Monteith shop online at UngulateCompendium.org
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