Instructor Notes

Class Announcements: remind students regarding any issues with upcoming tutorials, files, packages, etc.

Class Discussion

Pre-question discussion:

Start discussion by seeing if the class has experience with phenology. This can vary from class to class whether the concept was completely unfamiliar or you have a group of experts and will help you guage whether you need to spend more time on basic concepts are can push quickly to deeper concepts. Start by asking class how many of them have read or thoughts about phenology. Ask them about phenology change over time. Ask about what phenology changes they have been exposed to before. Half the class will have some familiarity with phenology.

Discussion Questions

What is phenology? Brainstorm some examples of phenology in animals or plants.

• Timing of activity - seasonal scale, within a year typically not across years.

How might a species “know” when to do certain activities? What kinds of cues might they be responding to? There are often external cues that are perceived by an individual. There are a variety of abiotic and biotic cues that students can list from photoperiod to flowering.

What are lags and what generates them?

• Lags are time delays between when an event occurs and the response to the event.
• Time lags are common in ecology as it often takes time for ecological processes to play out. Physiological responses take time (lags in generating new tissues either through growth or reproduction) mean that when a cue occurs, the response to that cue may not be seen for days, weeks, or even months.

Examine Figure 1 - focusing on the red and blue bands, how big is the shift in phenology? What data characteristics would you need to detect a shift of this magnitude? What data challenges are associated with this type of data?

• 1 month
• Need high frequency data over many years to detect this shift
• A paper reviewing phenology in plants (Cleland et al 2007 Shifting plant phenology in response to global change, TREE) found that across studies the average response seen is 2.3-5.1 days per decade
• Prompt students to think about what kinds of thingshumans care enough about to have daily data over decades (economic or cultural/societal values)

What effect did removing a competitor have on phenology of the other species? Are there any conections with last weeks material on no-analog communities?

• One species delays their reproductive season in the presence of the competitor while the other does not respond. There are also differences in the parameters fit to the environmental data, suggesting that how the species is responding to their environmental cues for reproduction are also changing. *In the no-analog paper, they authors argued that we might not see the entire niche of a species. In the phenology paper, if all we see is C. baileyi in the presence of kangaroo rats, then we would think Jan-Mar was their “preferred” timing and conditions. Only when the kangaroo rats are removed do we perhaps get a feel for what their preferred conditions might be.

What might broad intraspecific variability in how a species responds to an environmental driver mean for forecasting?

• Broad intraspecific variability either suggests there are many conditions that are suirable for reproduction and/or that there the drivers are weak (these can be flip sides of the same coin).
• The stronger the response to a narrow range of drivers, the better our ability to forecast will be.