Gothic, Colorado
As a resident of the Rocky Mountain Biological Lab (RMBL) from 2012-2014, I participated in two projects regarding animal decision making and environmental cues:
Project 1: Climate Monitoring
Researchers use a variety of technical equipment to study climate change. At RMBL, some researchers learn about environmental change just by watching ground squirrels.
Every year, scientists record the time that golden-mantled ground squirrels (Callospermophilus lateralis aka GMGS) emerge from hibernation in order to collect data on the environmental cues that they use to determine timing of emergence and reproduction. These are two helpful metrics to record changes in climate because research has shown correlations between these and environmental phenomena like rainfall, snowfall, and temperature. Ground squirrel mothers need to monitor the environment carefully to make life or death decisions. They must emerge early enough from hibernation in order to allow plenty of time for their pups to grow big and fat before the first snowfall. However, if they come out too early, there won't be enough vegetation to support the energy costs of reproduction and survival. GMGS are excellent indicator species for another reason, as well. The effects of climate change have an earlier and more drastic effect at high altitudes. As diurnal mammals that inhabit sub-alpine and alpine ecosystems, long-term trends in their hibernation and reproduction can help researchers track corresponding environmental changes and animal population movements before the effects of climate change reach lower, more populated areas of the world.
GMGS were trapped and given ear tags, unique dye marks (right), and some were given radio collars (middle) - photos by G. Dimijian
Project 2: Personality-Dependent Dispersal
Dispersal, the movement from an animal's natal habitat to site of first breeding, is a complex phenomenon. On the one hand, movement to a new site can help animals avoid inbreeding and competition and establish new territories with richer resources. On the other hand, it poses many risks- exposure to predators, competition with older residents, and energetic costs of travel.
GMGS demonstrate an unusual dispersal rate. Unlike most mammals in which only males disperse, GMGS have a 50% female dispersal rate as well. I examined the effects of social interactions, environmental boldness,and behavioral syndromes to determine whether these factors can predict whether female ground squirrels decide to stay or leave. The following year we used radio telemetry to track the newest pups and their movement to nearby populations. The squirrels travelled much further than expected, surprising everyone with new information on population dynamics about this well-studied animal.
Dispersal, the movement from an animal's natal habitat to site of first breeding, is a complex phenomenon. On the one hand, movement to a new site can help animals avoid inbreeding and competition and establish new territories with richer resources. On the other hand, it poses many risks- exposure to predators, competition with older residents, and energetic costs of travel.
GMGS demonstrate an unusual dispersal rate. Unlike most mammals in which only males disperse, GMGS have a 50% female dispersal rate as well. I examined the effects of social interactions, environmental boldness,and behavioral syndromes to determine whether these factors can predict whether female ground squirrels decide to stay or leave. The following year we used radio telemetry to track the newest pups and their movement to nearby populations. The squirrels travelled much further than expected, surprising everyone with new information on population dynamics about this well-studied animal.
Conducting radio telemetry on Mt. Gothic, the peak that gives the townsite its name - high altitude provides a better range for telemetry by removing obstacles between the antenna receiver and the squirrel collars' radio signals