Tracking Populations

http://earthref.org/SCC Scripps Classroom Connection

Populations on a kelp holdfast

How did we study those populations? Brought kelp into lab Visually spotted them Pulled them off the kelp Sorted them into another container Measured abundance of each taxa Assessed species richness/eveness

http://earthref.org/SCC Scripps Classroom Connection

What about more mobile species?

How do we study their populations?

Tag devices

Sensor Networks

http://earthref.org/SCC Scripps Classroom Connection

Mark-Recapture

Do you see all your friends in school everyday?

When you see someone you’ve never seen before what does this make you think about the size of your school?

The number of repeat encounters you have with friends each day is related to the size of your school.

Scripps Classroom Connection

http://earthref.org/SCC

Mark-Recapture

How many times you see the same person is related to how big your school population is.

Same goes for animal populations.

But you know what your friends look like.

Need to ID animals

http://earthref.org/SCC Scripps Classroom Connection

Mark-Recapture

Each time you mark an animal and recapture it, this tells you something about the population size.

Fish Tagging Lab

http://earthref.org/SCC Scripps Classroom Connection

More ways to study populations

Satellite Tagging & TrackingGeneticsPhoto ID Mark Recapture

http://earthref.org/SCC Scripps Classroom Connection