Bream Lab: Bream Lab: Relative WeightRelative Weight

BIOL 3500LBIOL 3500L

Dr. Christopher KodaniDr. Christopher Kodani

Learning Objectives (for Learning Objectives (for Lab Quiz)Lab Quiz)

Calculate relative weightCalculate relative weight Explain:Explain:

Relative weights, below 0.8, from 0.8 to 1.0, Relative weights, below 0.8, from 0.8 to 1.0, above 1.0above 1.0

Why using fish board is importantWhy using fish board is important Discuss example from Florida Fish & WildlifeDiscuss example from Florida Fish & Wildlife Identify largemouth bass, bluegill, warmouth, Identify largemouth bass, bluegill, warmouth,

redbreast sunfish, channel catfishredbreast sunfish, channel catfish Discuss linear and non-linear regressionDiscuss linear and non-linear regression

Shelford’s Tolerance Shelford’s Tolerance CurveCurve

Note Y-axis Note Y-axis “Performance”“Performance”

Could be some Could be some measure of measure of condition:condition: Speed of animalSpeed of animal Height of plantsHeight of plants # of offspring# of offspring

Relative WeightRelative Weight

For fish, condition measured as “Relative For fish, condition measured as “Relative Weight”Weight”

Ratio of actual weight to standard weightRatio of actual weight to standard weight Similar to “Body Mass Index” for humansSimilar to “Body Mass Index” for humans

CDC website CDC website http://www.cdc.gov/nccdphp/dnpa/bmi/adult_Bhttp://www.cdc.gov/nccdphp/dnpa/bmi/adult_BMI/about_adult_BMI.htmMI/about_adult_BMI.htm

Standard WeightStandard Weight What a fish “should” weighWhat a fish “should” weigh Depends uponDepends upon

Size of fishSize of fish SpeciesSpecies Other factors (region, sex, reproductive Other factors (region, sex, reproductive

condition)condition) Available in literatureAvailable in literature

Georgia Adopt-a-Lake ManualGeorgia Adopt-a-Lake Manual Alabama Cooperative Extension Alabama Cooperative Extension

http://www.aces.edu/pubs/docs/A/ANR-1193/http://www.aces.edu/pubs/docs/A/ANR-1193/

Fish MeasurementsFish Measurements

Florida Fish and Wildlife Florida Fish and Wildlife http://floridafisheries.com/Fishes/mehttp://floridafisheries.com/Fishes/measure.htmlasure.html Ignore girth, we only want lengthIgnore girth, we only want length Use fish board!Use fish board!

Calculating Relative Calculating Relative WeightWeight

Actual weight / standard weightActual weight / standard weight If you like, you can x100 for percentageIf you like, you can x100 for percentage

Identifying FishIdentifying Fish These could be present in Swan Lake:These could be present in Swan Lake:

Channel CatfishChannel Catfish Look like a cat!Look like a cat!

Largemouth BassLargemouth Bass Two distinct dorsal finsTwo distinct dorsal fins

Sunfishes a.k.a. “bream” (two dorsal fins Sunfishes a.k.a. “bream” (two dorsal fins merged)merged)

BluegillBluegill All black ear tabAll black ear tab

Redbreast sunfishRedbreast sunfish Has very long ear tabHas very long ear tab

WarmouthWarmouth Stripes on faceStripes on face

Fish ID Study ResourcesFish ID Study Resources Texas Parks Texas Parks

http://www.tpwd.state.tx.us/landwater/water/aquathttp://www.tpwd.state.tx.us/landwater/water/aquaticspecies/inland.phtml icspecies/inland.phtml

Virginia Fish & Wildlife Virginia Fish & Wildlife http://www.cnr.vt.edu/efish/families/centrarchidae.http://www.cnr.vt.edu/efish/families/centrarchidae.html html

NC State University NC State University http://www.ces.ncsu.edu/nreos/wild/fisheries/topichttp://www.ces.ncsu.edu/nreos/wild/fisheries/topics/fishidentification.htmls/fishidentification.html

Tennessee Wildlife Resources Agency Tennessee Wildlife Resources Agency http://www.ces.ncsu.edu/nreos/wild/fisheries/topichttp://www.ces.ncsu.edu/nreos/wild/fisheries/topics/fishidentification.html s/fishidentification.html

Florida Fish and Wildlife Florida Fish and Wildlife http://www.ces.ncsu.edu/nreos/wild/fisheries/topichttp://www.ces.ncsu.edu/nreos/wild/fisheries/topics/fishidentification.html s/fishidentification.html

Actual Research ExampleActual Research Example

Florida study shows flooding may Florida study shows flooding may improve some fish’s conditionimprove some fish’s condition

Florida Fish and Wildlife Florida Fish and Wildlife http://www.floridamarine.org/featurehttp://www.floridamarine.org/features/view_article.asp?id=24545s/view_article.asp?id=24545 Note box and whiskers plotNote box and whiskers plot

For Your NotebooksFor Your Notebooks Frequency Distribution Tables (separate Frequency Distribution Tables (separate

species)species) Body massBody mass Total lengthTotal length Relative weightRelative weight

Make histograms (separate species)Make histograms (separate species) One for lengthOne for length One for body massOne for body mass

Scatter Plot (all fish on one)Scatter Plot (all fish on one) Mass vs. lengthMass vs. length

Plus standard lab write up in your Plus standard lab write up in your notebook, by next lab (10 points)notebook, by next lab (10 points)

Frequency DistributionFrequency Distribution

An organized, An organized, summarized list of summarized list of measurementsmeasurements

Tells number Tells number within each within each intervalinterval Ex: Ages of people Ex: Ages of people

in a groupin a group

Age Age IntervalInterval

Number Number of of IndividuaIndividualsls

15 to 1915 to 19 110110

20 to 2420 to 24 254254

25 to 2925 to 29 397397

30 to 3430 to 34 8080

Frequency Distribution Frequency Distribution ExampleExample

Bluegills (cm): Bluegills (cm): 8.83, 9.25, 8.77, 8.83, 9.25, 8.77, 10.38, 9.31, 10.38, 9.31, 8.92, 10.22, 8.92, 10.22, 7.95, 9.74, 9.51, 7.95, 9.74, 9.51, 9.66, 10.42, 9.66, 10.42, 10.35, 8.82, 10.35, 8.82, 9.45, 7.84. 9.45, 7.84. 11.24, 11.06, 11.24, 11.06, 9.84, 10.759.84, 10.75

Body Body Length Length (cm)(cm)

Number of Number of IndividualsIndividuals

7.00 to 7.00 to 7.997.99

22

8.00 to 8.00 to 8.998.99

44

9.00 to 9.00 to 9.999.99

77

10.00 to 10.00 to 10.9910.99

55

11.00 to 11.00 to 11.9911.99

22

HistogramHistogram

Scatter PlotScatter Plot

MeanMean

Mean = averageMean = average Not the only measure of centrality!Not the only measure of centrality!

Also median and mode! Also median and mode! ExampleExample

Bluegills (cm): 8.83, 9.25, 8.77, 10.38, 9.31, Bluegills (cm): 8.83, 9.25, 8.77, 10.38, 9.31, 8.92, 10.22, 7.95, 9.74, 9.51, 9.66, 10.42, 8.92, 10.22, 7.95, 9.74, 9.51, 9.66, 10.42, 10.35, 8.82, 9.45, 7.84. 11.24, 11.06, 9.84, 10.35, 8.82, 9.45, 7.84. 11.24, 11.06, 9.84, 10.7510.75

ModeMode Mode = most common Mode = most common

categorycategory Bluegills (cm)Bluegills (cm)

8.83, 9.25, 8.77, 10.38, 8.83, 9.25, 8.77, 10.38, 9.31, 8.92, 10.22, 7.95, 9.31, 8.92, 10.22, 7.95, 9.74, 9.51, 9.66, 10.42, 9.74, 9.51, 9.66, 10.42, 10.35, 8.82, 9.45, 7.84. 10.35, 8.82, 9.45, 7.84. 11.24, 11.06, 9.84, 11.24, 11.06, 9.84, 10.7510.75

MedianMedian

Median = the Median = the “middle one” “middle one” (for odd (for odd sample size)sample size) Or average of Or average of

the two in the two in the middle the middle for even for even sample sizesample size

Body Body Length (cm)Length (cm)

Number of Number of IndividualsIndividuals

7.00 to 7.997.00 to 7.99 22

8.00 to 8.998.00 to 8.99 44

9.00 to 9.999.00 to 9.99 77

10.00 to 10.00 to 10.9910.99

55

11.00 to 11.00 to 11.9911.99

22

RegressionRegression

Makes a “best fit” line for dataMakes a “best fit” line for data We can use MS Excel’s Graph We can use MS Excel’s Graph

Wizard functionWizard function Enter length into column AEnter length into column A Enter body mass into column BEnter body mass into column B Use Graph Wizard to graph of bluegill Use Graph Wizard to graph of bluegill

weight vs. lengthweight vs. length

Linear vs. Non-Linear Linear vs. Non-Linear RegressionRegression

Linear regressionLinear regression Assumes straight-line Assumes straight-line

relationshiprelationship y = mx + by = mx + b

Non-linear regressionNon-linear regression Uses other equations for lineUses other equations for line

Y = a + bx + cxY = a + bx + cx22

In Excel, click on lineIn Excel, click on line Add trendlineAdd trendline Choose linear or powerChoose linear or power Options:Options:

Show equationShow equation Show rShow r22

y = 0.1164x2.2756

R2 = 0.9185

0

50

100

150

200

250

0 10 20 30

Length (cm)

Mas

s (g

) Series1

Power (Series1)

Linear (Series1)