Lesson 01: Adult Growth

Sturgeon Lesson Plan #1

Background:

Procedure:

Day 1

1. Discuss the process of conducting the adult lake sturgeon population census survey.  Begin discussion about how, where and when the survey is conducted.  Also, describe the details or methods associated with the information collected.  Topics to discuss during the lecture may include:
   1. Survey is conducted in the early spring when river temperatures reach 11 degrees Celsius.  This is typically when Lake Sturgeon begin entering the river to spawn (Forsythe et al. (2012) CJFAS galleys, Forsythe et al. (2012) J. Fish Biology).  Discuss observations of repeatability of timing and location of spawning and the environmental cues adults use to guide decision of when to migrate.
   2. Survey is conducted on the Black River below Tower-Kleiber Dam.  Sample sites are listed as “Zones” and are numbered 1 thru 7.  Zone 1 (abundant large rock) is the farthest most upstream sample region which is characterized more as a prime spawning area compared to habitat located say in Zone 7 (abundant fine sediment/sand).
   3. Data collected are used to estimate harvest numbers as well as provide researchers with baseline information regarding lake sturgeon growth and reproduction.
2. Provide students with the data from Excel.
   1. Now that the students have the data, they can transform the data from Metric to English units.  Scientists collect data using Metric units to accommodate how most of the world collects their data.  This makes comparing results across geographical regions much easier.
      1.  This exercise is done simply to show students how to convert Metric to English, check the Tools manual for more information.
   2. Now that the raw data has been converted, ask the students to develop questions about features of the data which may be useful before any data are graphed.  Based on the data collected what questions can the data are used to answer?  List the questions on the whiteboard and select those questions which are mentioned most frequently by students.
      1. If not mentioned, other sample questions may include:
         1. Are Male and Female Lake Sturgeon similar in size (total length, girth, etc.)?
            1. Answer:  Typically female are larger in both total length and girth.
         2. Do individual Lake Sturgeon prefer a specific spawning zone?
            1. Answer:  Some evidence suggests that early spawners prefer more upstream habitats
         3. Do Male or Female Lake Sturgeon spawn at similar intervals?  In other words, can you tell from the data provided how often these adults spawn?
            1. Answer:  It appears that males spawn every two years, while females spawn every three.
         4. Why might researchers collect Fork Length if Total Length is already collected?  What is the difference between Total and Fork Length?
            1. Answer:  Total length is measured to the farthest tip of the caudal (or tail) fin.  Often their fins are chipped or have been reduced as a result of aging so fork length often provides a more accurate estimate of growth over time.
         5. In what year can researchers expect to capture Female #1 again?
            1. Answer:  2014
         6. In what year can researchers expect to capture Male #3 again?
            1. Answer: 2012

Day 2

1. Instruct students on how to create a graph first by hand and then with Excel using the data provided during previous lecture.
2. For Example, let us hypothesize that at first capture, the average Total Length is equal between that of male and that of female lake sturgeon.
3. Instruct students to try and provide a biological explanation as to why there appears to be a difference between the sizes of first time spawning males versus first time spawning females.  How does this affect their initial hypothesis?  For example, if their null hypothesis was that male and female Lake Sturgeon would be similar in size at the first capture event, ask the students why this does not appear to be the case.
4. With a partner, ask students to choose a question from the list of whiteboard questions created the previous day.
5. Using the questions those students came up with; ask them to attempt to answer their questions using the graphed data that they create by hand or in Excel on their own.  Utilize the Tools offered from the website to see examples of how data can be created or interpreted.
6. Each group will need a process of science worksheet to guide the development of a hypothesis and prediction for their question.
7. Allow time for students to analyze and compile data for their hypothesis.
8. Students present their initial question, hypothesis, data, additional questions that arose and conclusion for peer review and discussion.  The teacher should keep a running list of the additional question that arose during the analysis.  This is a good reminder of the circular nature of science.

Extended Learning Opportunities:

Assessment and Evaluation: