Population Density Population Density LabLab

Chapter 35Chapter 35

Biology Honors Biology Honors

InstructionsInstructions

AT the end of the presentation…AT the end of the presentation… Get into Groups of threeGet into Groups of three Bring up a paper with your group members Bring up a paper with your group members

names to receive your field equipmentnames to receive your field equipment Pick a material personPick a material person

This person must make sure the bag is returned This person must make sure the bag is returned in its original condition to the instructor at 9:15 in its original condition to the instructor at 9:15 amam

BackgroundBackground

You and your fellow You and your fellow ecologists have ecologists have discovered a rare discovered a rare spotted beanie spotted beanie population along the population along the outskirts of Hialeah outskirts of Hialeah Gardens High School. Gardens High School. They are small and very They are small and very quick during the day and quick during the day and become sessile (burrow become sessile (burrow in the ground and do not in the ground and do not move) creatures at nightmove) creatures at night

PurposePurpose

To use the mark-recapture and quadrant To use the mark-recapture and quadrant sampling techniques to determine the sampling techniques to determine the population of the rare spotted beanie population of the rare spotted beanie speciesspecies

To report your findings to the National To report your findings to the National Spotted Beanie Association so they can Spotted Beanie Association so they can update their ecology journalsupdate their ecology journals

MaterialsMaterials

In each brown paper bag there should be:In each brown paper bag there should be: One permanent marker (if it is yellow, bring it up One permanent marker (if it is yellow, bring it up

front later to exchange for a darker color)front later to exchange for a darker color) One rulerOne ruler A ziploc baggie with the unknown population of rare A ziploc baggie with the unknown population of rare

spotted beaniesspotted beanies A cupA cup A sheet of aluminum foil (this will be handed to A sheet of aluminum foil (this will be handed to

groups of three)groups of three)

ProceduresProcedures Based on what you have learned about the Based on what you have learned about the

various techniques used to estimate various techniques used to estimate populations, you will develop your own method populations, you will develop your own method for quadrant sampling and the mark-recapture for quadrant sampling and the mark-recapture method. Here are some pointers:method. Here are some pointers: Aluminum sheet is to be used for the quadrant Aluminum sheet is to be used for the quadrant

samplingsampling Fold up edges to make the aluminum sheet like a shallow Fold up edges to make the aluminum sheet like a shallow

pan so the beanies won’t escapepan so the beanies won’t escape Use permenent marker and ruler to make quadrantsUse permenent marker and ruler to make quadrants

Brown paper bag is to represent the ecosystem of Brown paper bag is to represent the ecosystem of the rare spotted beanies for the mark-recapture the rare spotted beanies for the mark-recapture methodmethod Use permanent marker to make a distinguishable mark on Use permanent marker to make a distinguishable mark on

your organism for the first captureyour organism for the first capture Use the cup to capture beanies fromtheir ecosystem Use the cup to capture beanies fromtheir ecosystem

CalculationsCalculations

Here is a refresher:Here is a refresher: Population density= (individuals/unit area)Population density= (individuals/unit area) Quadrant sampling involves counting number of Quadrant sampling involves counting number of

species in each quadrant then repeating with several species in each quadrant then repeating with several quadrants and then average your results to get avg. quadrants and then average your results to get avg. pop. Densitypop. Density

More quadrants= more accurateMore quadrants= more accurate MR= MR= (# in 1(# in 1stst capture x # in 2 capture x # in 2ndnd capture) capture)

# of marked individuals in second # of marked individuals in second capturecapture

Remember, in research, you need to have at least Remember, in research, you need to have at least three trial for each methodthree trial for each method

Write-UpWrite-Up Purpose Purpose Background Background

(at (at least one page, double spaced least one page, double spaced on background of population ecology, methods of calculating on background of population ecology, methods of calculating population, and info from this lab)population, and info from this lab)

Materials and Procedures (VERY specific…for quadrant sampling and for mark-recapture)Materials and Procedures (VERY specific…for quadrant sampling and for mark-recapture) Calculations (Show ALL work and UNITS!!!!)Calculations (Show ALL work and UNITS!!!!)

Quadrant samplingQuadrant sampling 3 trials3 trials Scale 1cm=?mScale 1cm=?m Area of each quadrant= length (in m) x width (in m)Area of each quadrant= length (in m) x width (in m) Total number of quadrantsTotal number of quadrants Average population density for EACH trial (sum of pop density of each quadrant/# of quadrants)Average population density for EACH trial (sum of pop density of each quadrant/# of quadrants)

Mark-RecaptureMark-Recapture 3 trials3 trials Total population from each trialTotal population from each trial Procedure for determining population density for each trialProcedure for determining population density for each trial Population density for each mark-recapture trial (total individuals in trial/total area of ecosystem in Population density for each mark-recapture trial (total individuals in trial/total area of ecosystem in

meters…total area of all your quadrants together in meters)meters…total area of all your quadrants together in meters) Results (Tables for each method and trial) (Totals for each method and trial…optional: graphs)Results (Tables for each method and trial) (Totals for each method and trial…optional: graphs) Conclusion (One to two pages…12 pt font, times new roman font, double spaced…worth the most)Conclusion (One to two pages…12 pt font, times new roman font, double spaced…worth the most)

Analyze your result. Explain how you got you final population number. Describe limits to accuracy, Analyze your result. Explain how you got you final population number. Describe limits to accuracy, problems you may have encountered, how this simulation is different from what would actually occur in problems you may have encountered, how this simulation is different from what would actually occur in nature. What method do you think was most accurate? Why? How could this have been improved? nature. What method do you think was most accurate? Why? How could this have been improved? What if the beanies were never sessile? What if the beanies were never sessile? Include any other relevant information. This section should be Include any other relevant information. This section should be very thorough very thorough (hint a page or two) (hint a page or two)

Parameters for Lab Parameters for Lab ReportReport

Title PageTitle Page Headings for each section (nothing too Headings for each section (nothing too

elaborate please! Keep It Simple!)elaborate please! Keep It Simple!) 12 point font12 point font Double SpacedDouble Spaced Times New Roman or ArialTimes New Roman or Arial 1 inch margins all around (top, bottom, left, 1 inch margins all around (top, bottom, left,

right)right)

Turning in at the end of Turning in at the end of class…class…

Rough draft of your write-upRough draft of your write-up Everyone in the group MUST turn in their Everyone in the group MUST turn in their

own paperown paper

Will be graded and returned next classWill be graded and returned next class Formal TYPED write-up is due Tuesday Formal TYPED write-up is due Tuesday

March 3rdMarch 3rd