Session 1 CKMR thought experiments and labs

In the second half of this course, we’re going to switch gears and delve into some code. But first, we’re going to conduct a few thought experiments to try to get you to think critically about some of the CKMR concepts we’ve covered so far. We’ll also be switching from slides to this “book” - hopefully this will be a useful resource for those of you who want to look back at course content.

1.1 Afternoon schedule

An approximate schedule for the afternoon is

  • 1:00 - 1:30 Thought experiments
  • 1:30 - 2:30 Kin finding lab
  • 2:30 - 2:45 Break
  • 2:45 - 3:30 White shark estimation example
  • 3:30 - 4:30 CKMR Design
  • 4:30 - 5:00 Open! Feel free to play with code or ask us questions

1.2 Thought experiments

We think it would be useful for participants to break into small groups for this one. So let’s do that.

Note that there are not necessarily any right or wrong answers to these exercises - but we’re interested to hear what people come up with!

1.2.1 Thought experiment 1

Assume that mitochondrial haplotype diversity is high, so that we can definitely tell MHSPs from PHSPs. What might be causes for the number of PHSPs being significantly greater than the number of MHSPs?

1.2.2 Thought experiment 2

What sampling or population conditions might lead to negative bias in CKMR abundance estimates? How about positive bias in abundance estimates?

1.2.3 Thought experiment 3

Imagine that we are conducting a CKMR experiment using POPs. Given that CKMR estimators of abundance are in essence backdated to the year of the offspring’s birth, how might we sample animal populations to get better precision in the most recent years?

1.2.4 Thought experiment 4

Suppose we are thinking about using CKMR to estimate the abundance of a migratory goose population, where males and females routinely form lifelong pair bonds, and goslings stay with their parents for the first year of life or so. Genetics samples are available from parts collection surveys (from hunter harvests), and the goal is to estimate adult abundance for a particular flyway. What are some things to consider when designing a CKMR study with these data?