BEFORE YOU OPEN ANY FILES:

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1 Dive Analysis Lab * Make sure to download all the data files for the lab onto your computer. * Bring your computer to lab. * Bring a blank disk or memory stick to class to save your work and files. The purpose of this lab is to introduce you to the tools used to examine the at-sea behavior of marine mammals. You will take data collected from a variety of species and find differences and similarities between species and/or families and draw conclusions based on biology, physiology, and ecology. To look at the at-sea behavior of marine mammals researchers equip animals with time-depth (dive) recorders. These instruments sample many parameters of diving behavior and the environment including: pressure (depth), water temperature, light levels, salinity, and swim velocity. Researchers have the ability to select the variables that are sampled and the rate at which they are sampled. The most recent tags have memory storage of up to 64 Mb. This means for the 8 month migration of a northern elephant seal depth, water temperature, and light can be sampled every 4 seconds for the entire trip. Dive recorders are either archival (Wildlife computers, for ex. Mk9) or satellite linked (Sea Mammal Research Unit, SRDL; Figure 1). Archival tags store all of the data collected and need to be recovered (the animal must be recaptured). Satellite linked instruments transmit data through the ARGOS satellite system and animals do not need to be recaptured. Because archival tags have such a large memory they can store precise data points and provide information on a fine scale (seconds). Once archival tags are recovered the instruments are downloaded onto a PC and the analysis begins. Satellite linked tags must summarize data due to the limits of the satellite system so you lose the more detailed information on behavior but data is available in near real time. The type of tag used depends on the study species and the questions the researcher is asking. In this lab you will use data from both types of recorders. Figure 1. Above left is a satellite relay data logger (SRDL). At right is a MK 9 time depth, temperature and light level archival tag (Wildlife Computers, Redmond WA).

2 LAB PROCEDURES: To Begin: 1) BEFORE YOU OPEN ANY FILES: If you are using a borrowed laptop, make a copy of the Bio129 folder on the desktop and rename it with your last name. All the work you do will be done from this new file and no changes should be made to the original folder! 2) Plot dive profiles. This will give you a qualitative look at the data collected for each species and is what researchers see when they first download data. These are incomplete records since the total size would be too large to plot in excel. Open file Ag raw data.xls in excel. There will be 3 columns labeled Date, Time, and Depth (m). Using the graphing function in excel create a line graph of dive depth vs. time. It should look similar to Figure 2. To make a graph go to Insert on the main menu and select chart. A chart wizard window will open with a selection of chart types. Choose line and for chart sub-type select the first graph, click Next. It will ask for a data range. Using your mouse highlight all of the data from the Time and Depth columns. Try this little excel trick to avoid spending time dragging down to highlight the whole column - highlight the first cell in the time and dive columns and then press the Shift, Control and down arrow keys which will select all the rows in those two columns. After creating the main part of the figure you can now add titles, change axis, move the legend, change background color, etc. This will be valuable for you when you make your final figures for the report. For the last step, decide if you want the chart placed on the page you are working on or in a new worksheet and select Finish. Your graph will need to be modified to look like the figures below. Double click on the y-axis and a Format axis window will open. This window will also be valuable to you when you format your graphs for the report. For now, choose the scale tab. Near the bottom, you will see Values in reverse order and Category (x) crosses at max value. Check both of those boxes and select OK. You can also use this window to change your axis scale. What patterns do you see in this female s dive behavior? How deep does she dive? Are her dive depths consistent or variable? Does she dive continuously or intermittently? Looking at dive plots we can put together a qualitative description of an animals dive behavior. Now, make dive plots for the other animals to look at the differences in behavior. This is always the first step for researchers Families Otariidae and Phocidae (seals and sea lions): Ag raw data.xls, Ap raw data.xls, Cu raw data.xls, Ma raw data.xls, Nc raw data.xls and Zc raw data.xls Families Balaenopteridae, Physeteridae and Delphinidae (whales): Bm raw data.xls, Gm raw data.xls, Md raw data.xls, Oo raw data.xls, Pm raw data.xls and Ziphc raw data.xls Qualitatively compare the dive files you have created. How do dive shapes, dive durations, depth, etc. compare between species? Within a dive record how does behavior change with time of day? Use these qualitative comparisons or others to decide what factors you want to examine for your lab report.

3 Figure 2: Dive plot for an adult female Antarctic fur seal (Arctocephalus gazella). 3) Next, all of the files were run through an analysis program (IKNOS, Tremblay unplublished) to quantitatively measure the characteristics of the dive behavior. This provides a list of characteristics for each dive on the record. Below is a description of the how dive characteristics are calculated (Figure 3). Units are provided in parentheses. Maximum dive depth (meters): A Dive duration (sec): B to C (full dive including descent, bottom time and ascent to surface) Bottom time (sec): D to E Post dive surface interval (sec): C to F (end of dive to beginning of next dive) Dive cycle (sec): B to F (one complete dive and the surface interval that follows) Descent rate (m/s): Δ Depth / Δ Time (From B to D) Ascent rate (m/s): Δ Depth / Δ Time (From E to C) Wiggles: 1,2,3,4, etc. Inflection points during bottom time. Figure 3: Description of dive characteristic definitions. Solid line dive profile is a benthic (bottom) feeder and dashed dive profile is an epipelagic feeder. 4) For the remaining excel files you will have columns set up similar to the table on the next page: Families Otariidae and Phocidae (seals and sea lions): Ag Female1, Ag Female2, Ag Female3, Ap Female1, Ap Female2, Ap Female3, Hl 1.xls, Ma Female1, Ma Female2, Ma Female3, Nc Female1, Nc Female2, Nc Female3, Zc Female1, Zc Female2, Zc Female3

4 Families Balaenopteridae, Physeteridae and Delphinidae (whales): Bm 1.xls, Gm 1.xls, Md 1.xls, Oo 1.xls, Pm 1.xls and Ziphc 1.xls Dive # Date Time (GMT) Max Depth (m) Duration (mm:ss) Post dive interval (hh:mm:ss) Bottom Time (mm:ss) Wiggles Descent Rate (m/s) Ascent Rate (m/s) 1 01/24/05 17:54: :32 0:00:00 00: /24/05 18:00: :18 0:05:42 00: /24/05 18:01: :12 0:00:04 00: /24/05 18:01: :06 0:00:20 00: Note: The files from the crabeater seals (Lc Female1.xls, Lc Female2.xls, Lc Female3.xls) and leopard seal (Hl 1.xls) do not have a bottom time and wiggles column. 5) The rest is up to you. Develop a hypothesis based on your qualitative assessments and/or material covered in class. Use graphs and basic statistics (avg, max, min, *your TA will show you how to do this in excel*) to test this hypothesis. Example 1: Based on what you know about diving physiology, dive duration should be related to oxygen stores (and more specifically mass). You can find the average dive depth for each species and compare that to mass. Is there a pattern? What other factors might influence dive depth? These are things you could cover in the discussion. Example 2: Since epipelagic foragers feed on vertically migrating prey you should see a change in dive depth with time of day. Can you determine the foraging pattern of each of the species (epipelagic or benthic)? Your TA will provide other ideas for hypotheses to test. To examine the relationship between dive characteristics it will be useful to make XY scatter plots (dive depth vs. dive duration or dive duration vs. post dive interval). To make a scatter plot go to Insert on the main menu and select chart. A chart wizard window will open with a selection of chart types. Choose XY (Scatter) and for chart sub-type select the first graph, click Next. It will ask for a data range. Using your mouse highlight all of the data from two columns (dive depth and dive duration, for example). For the next step you can add titles, change axis, move the legend, change background color, etc. This will be valuable for you when you make your final figures for the report. For the last step, decide if you want the chart placed on the page you are working on or in a new worksheet and select Finish (Figure 4). Figure 4: Relationship between dive depth (m) and dive duration (s) for an adult female Antarctic fur seal. 6) Make sure you save all of your work and any of the files you think you will need for your report onto your disk. You will not have access to these computers after lab section is over.

5 WRITING YOUR LAB REPORT Now the fun really begins. You must write a 2-3 page report outlining the results of your analysis. The report should be in scientific paper format, including: 1. A brief introduction explaining the background for the lab (understanding at-sea behavior, comparisons between species, etc.). This will be specifically related to the analysis you chose to do. Clearly state the purpose of your investigation. 2. A materials and methods section outlining how the data was acquired and analyzed. You will need to include the basics of the tags used, study species, and analysis variables. Focus the majority of the section on the specific analysis you did with the data provided. Remember include enough information so another person can replicate your analysis and results. 3. A results section should describe the analysis in a clear and concise manner. At the very least this section should include a table with the means ± standard deviations for each of the parameters you examined for each species (max dive depth, dive duration, ascent rate, etc). You can take the analysis in any direction you want from here (see suggestions above or ask your TA). Just remember with the analysis to ask yourself is this a meaningful relationship (i.e., is there any biological relevance)? Be creative, chances are the deeper you take your analysis, the better your grade will be. Tables and figures are always useful for illustrating your findings. Remember to label the axes and do not forget to include the proper units on both graphs and tables. Tables and graphs should always be accompanied by a legend that describes in words what is being displayed. 4. A discussion section where you interpret your results. For example, if you found differences in some parameter between phocids and otariids, what behavioral, physiological or ecological factors could be responsible? Use topics from class to help explain the differences. Also, make sure to tie the discussion into your introduction for a complete paper. 5. Although it is not required, if you use other scientific literature for the report you must include a literature cited section. EXCEL TIPS * Formulas for excel always start with the = (equals) sign, followed by the equation. * Mean = If you are calculating a mean then the formula is: =avg(a2:a4) * Sum = If you are calculating a sum then the formula is =sum(a2:a4) * Max = If you want to know the maximum value in a series the formula is =max(a2:a4) * Min = If you want to know the minimum value in a series the formula is =min(a2:a4)