Presence of Escherichia coli with Cladophora Algae

 

Chantalle Carver

Liann Liegler

Erinne Sonnenberg

 

Abstract

            On four occasions in October 2008 water samples from beaches on the Western coast of Lake Michigan were taken.  On each occasion samples were taken from water near Cladophora, within 0.25 m, and water with no Cladophora present for at least 1.5 m.  These samples were tested for E. coli using petrifilm and counting colonies.  Our results were not significant because our p-value was 0.346.

 

Introduction

            Escherichia coli, generally known as E. coli, is a common bacteria that can live with or without oxygen making it facultatively anaerobic.  E. coli is present in humans and animals; it exits the body in fecal matter.  Some strains of E. coli can be pathogenic and cause illness in humans.  E. coli can also be found in water bodies such as lakes in rivers.  The amount of E. coli present in a water body can be a determining factor for how much fecal matter is present (Bootsma, Janssen, 2005)  In this experiment we are referring to E. coli found on the Western shores of Lake Michigan. 

Cladophora glomerata is filamentous green algae.  It is generally found on the beaches of the great lakes, including Lake Michigan (Wisconsin DNR, 2006).  Cladophora has been found to hold a large amount of possible pathogenic bacteria including E. coli (Ishii, et. al., 2006).  The presence of Cladophora has become a nuisance for many reasons.  When this alga becomes prominent it can lead to foul smelling beaches in addition to an unsightly green blanket on the shores.  This results in lowered beach use and can have negative economic consequences such as lowering property value (Bootsma, Janssen, 2005).  The algae and its ability to harbor possible pathogens such as E. coli may have reduced the quality of drinking water in addition to making the beaches of Lake Michigan less desirable (Bootsma, Janssen, 2005). 

Some possible reason for the increase in the amount of Cladophora is lower lake levels, changing currents and possibly the presence of Zebra mussels (Wisconsin DNR, 2006).  Certain Algae, including, Cladophora have been found to have large amounts of E. coli because they supply nutrients and can protect the bacteria from predation, radiation, or other harmful environmental stresses (Ishii, et. al., 2006).  Since E. coli is an opportunistic pathogen we wanted to find out if it is more prevalent in water with Cladophora or water without any visible Cladophora.  Our hypothesis was: the E. coli levels of the Western beaches of Lake Michigan will have a higher E. coli level where Cladophora is present.

 

Methods and Materials

            For this experiment we took samples from four beaches on the West coast of Lake Michigan including Bradford Beach, South Shore Yacht Club Beach, Grant Park Beach and Bender Beach.  These are all located in Milwaukee County, Wisconsin.  Cladophora was located on each beach using a sample photograph from the Great Lakes Sea Grant Extention Office.   Samples were taken on four different occasions, 10/21/08, 10/23/08, 10/25/08 and 10/28/08.  On all of the above dates 2 samples were taken from each of the four beaches.  The first sample was taken from water located near Cladophora (within .25 m of algae).  The second sample was taken from water where no Cladophora was present (at least 1.5 m with no algae present in any direction).  After each sample was collected it was refrigerated at 3°C. 

            On October 31, 2008 1mL of each sample was placed on a 3M Petrifilm Count Plate (Carolina, item # 82-4080).  This was done using a sterile pipette for each sample.  Using sterile technique the samples were cultured for 72 hours at 37°C, and observed by the stained blue colonies on the petrifilm.  The results were recorded by counting the stained blue colonies from each sample.

 

Results

The blue colonies were counted and averaged for samples taken near algae (within. 25 m).  The average number of E. coli colonies near Cladophora was 1.647.  This had a standard deviation of 1.9.  The blue colonies were counted and averaged for samples taken with no algae present (at least 1.5 m in any direction).  The average number of E. coli colonies that grew from water where no Cladophora was present was 1.823.  This had a standard deviation of 2.7.  There was no significant difference in the E. coli colonies in relation to the distance from Cladaphora (Fig. 1, P= .345 ). A 2-tailed upaired t-test was used to determine the P-value of our experiment.Our hypothesis was not supported because there was not a significant statistical difference.

Figure 1. E.coli colonies near and away from Cladaphora Algae

 
 

 

 

 

 

 

 

 

 

 


Discussion

            One possible reason our hypothesis was not supported could be that E. coli near Cladophora might migrate into the alga, since it has moved into the algae there would be less directly around it, where samples were taken.  The E. coli would find nutrients and protection in the alga making it an ideal place to get into and stay (Ishii, et. al., 2006).  This would make the E. coli levels near the Cladophora lower, which we saw in this experiment. 

            If we were to repeat this experiment we would take samples from different times of the year.  When samples were being taken some areas of the Cladaphora Algae were clearly dying.  This would inhibit the bacterial contents.  It would be beneficial to take samples mid to late summer when the algae are at their peak.  Another factor we could consider in future testing would be to take actual samples of the algae and see what the E.coli count is. 

            When conducting this experiment we considered Cladophora to be a major factor in the presence of E.coli on the beaches and shores of Lake Michigan.  In this experiment we would be advocating for removal or control of Cladophora growth.  To do this we would have to look at the ecosystem of the algae.  The algae thrives with large amounts of sunlight and phosphorous.

            When dreissenid mussels, also known as zebra mussels, where introduced into the Great Lakes the balance of the ecosystem was disturbed.  The colonies of Zebra mussels altered nutrient flow, including phosphorous.  Phosphorous from the benthic zone or bottom of the lake was being moved around and there was more available for the growth of Cladophora (Higgins, et. al., 2008).  Zebra mussels also filter the water and they tend to be abundant where it is rocky.  This filtration leaves the water clearer and Cladophora has a higher rate of light penetration (Bootsma, Janssen, 2005). 

            When we were testing our hypothesis we did not consider why there was such an abundant amount of these problematic algae, just that it would be better if it were removed.  After finding this information we realize this problem is much more complicated than simply removing the algae.  It appears a major source of the problem was a disruption of the ecosystem when the zebra mussels were introduced.  There is no easy fix when dealing with an entire ecosystem.   

           

 

 

 

References

 

Bootsma, H. (2005). Cladophora Abundance and Physical/Chemical Conditions in the Milwaukee Region of Lake Michigan, Overview - May 2005 (Summary).  University of Wisconsin-Milwaukee Great Lakes WATER Insititute.  Retrieved on November 1, 2008 from: http://v3.mmsd.com/AssetsClient/Documents/waterqualityresearch/cladophora_report2.pdf

 

Bootsma, H., Janssen J. (2005). Cladophora.   University of Wisconsin-Milwaukee Great Lakes WATER Insititute.  Retrieved on November 1, 2008 from: http://www.glwi.uwm.edu/research/aquaticecology/cladophora/

 

GLERL-Great Lakes Sea Grant Extention Office. (2006). Green Algae -Chlorophyta -Cladophora spp.  Retrieved from: http://www.glerl.noaa.gov/seagrant/GLWL/Algae/Chlorophyta/Cards/Cladophora.html

 

Higgins, S., Malkin, S., ToddHowell, E., Guildford, S., Campbell, L., Hiriart-Baer, V., Hecky, R. (2008).  An Ecological Review of Cladaphora Glomerata (Chlorophyta) in the Laurentian Great Lakes.  Journal of Phycology. Vol 44 No 4.  Pp 839-854 (16).  Retrieved November 15, 2008 from: http://www.ingentaconnect.com/content/bsc/jpy/2008/00000044/00000004/art00001

 

 

Ishii,S., Yan,T.,Shively,D., Byappanahalli,M.,  Whitman,R., Sadowsky,M.(2006). Cladophora (Chlorophyta) spp. Harbor Human Bacterial Pathogens in Nearshore Water of Lake Michigan.[Elecgtronic version] Applied and Environmental Microbiology,Vol 72, No 7, p.4545-4553.  Retrieved from: http://aem.asm.org/cgi/content/full/72/7/4545

 

Wisconsin Department of Natural Resources. (2006). Cladaphora, 2006 Water Quality
Report to Congress.
  Retrieved November 1, 2008, from: http://www.dnr.state.wi.us/org/water/wm/watersummary/305b_2006/cladaphora.htm

 

Wisconsin State Legislature. (2001).  Beach Task Force.  Q & A on Cladaphora. Retrieved November 1, 2008 from: http://www.legis.state.wi.us/assembly/asm19/news/Beaches/cladaphora.htm

 

 

 

 

Internet Source Worksheet

 

Most Internet sites are not appropriate references for academic work.  The purpose of this form is to allow you to provide evidence that your Internet source is a valid source of technical scientific information.  If this form is incomplete or unconvincing, your Internet source will not be accepted.  DO NOT complete this form if you used an electronic database to retrieve a copy of a scientific journal article.

 

Title of Web Site:  Q & A on Cladaphora

 

 

Website URL:  http://www.legis.state.wi.us/assembly/asm19/news/Beaches/cladaphora.htm

 

 

 

 

Author of Web Site (must have an author, can be an organization such as the Wisconsin Department of Natural Resources):

 

South East Wisconsin Beach Task Force

 

Last update of site (must be within 5 years):

 

2002

 

 

Evidence that the site is a valid source of technical scientific information (this will determine whether your site is acceptable, so complete it carefully and completely):

 

  • This is a government web site
  • It is an informing web site about Cladophora Algae in relation to information from the Milwaukee metropolitan sewage district

 

 

 

 

 

 

 

 

 

 

 

 

 

Internet Source Worksheet

 

Most Internet sites are not appropriate references for academic work.  The purpose of this form is to allow you to provide evidence that your Internet source is a valid source of technical scientific information.  If this form is incomplete or unconvincing, your Internet source will not be accepted.  DO NOT complete this form if you used an electronic database to retrieve a copy of a scientific journal article.

 

Title of Web Site: Cladaphora, 2006 Water Quality Report to Congress

 

 

Website URL: http://www.dnr.state.wi.us/org/water/wm/watersummary/305b_2006/cladaphora.htm

 

 

 

 

Author of Web Site (must have an author, can be an organization such as the Wisconsin Department of Natural Resources):

 

Wisconsin Department of Natural Resources

 

Last update of site (must be within 5 years):

2006

 

 

Evidence that the site is a valid source of technical scientific information (this will determine whether your site is acceptable, so complete it carefully and completely):

  • Department of Natural Resources
  • Report to congress

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Internet Source Worksheet

 

Most Internet sites are not appropriate references for academic work.  The purpose of this form is to allow you to provide evidence that your Internet source is a valid source of technical scientific information.  If this form is incomplete or unconvincing, your Internet source will not be accepted.  DO NOT complete this form if you used an electronic database to retrieve a copy of a scientific journal article.

 

Title of Web Site:

Green Algae
Chlorophyta
Cladophora spp.

 

Website URL: http://www.glerl.noaa.gov/seagrant/GLWL/Algae/Chlorophyta/Cards/Cladophora.html

 

 

 

 

Author of Web Site (must have an author, can be an organization such as the Wisconsin Department of Natural Resources):

 

 

Great Lakes Environmental Research Lab, Sea Grant Lakes Network

 

Last update of site (must be within 5 years):

2006

 

Evidence that the site is a valid source of technical scientific information (this will determine whether your site is acceptable, so complete it carefully and completely):

  • Research site containing good picture of Cladophora glomerata

 

 

 

 

 

 

 

 

 

 

 

Internet Source Worksheet

 

Most Internet sites are not appropriate references for academic work.  The purpose of this form is to allow you to provide evidence that your Internet source is a valid source of technical scientific information.  If this form is incomplete or unconvincing, your Internet source will not be accepted.  DO NOT complete this form if you used an electronic database to retrieve a copy of a scientific journal article.

 

Title of Web Site: Cladophora

 

 

Website URL: http://www.glwi.uwm.edu/research/aquaticecology/cladophora/

 

 

 

Author of Web Site (must have an author, can be an organization such as the Wisconsin Department of Natural Resources):

Harvey Bootsma, John Janssen

 

 

Last update of site (must be within 5 years):

2008

 

 

Evidence that the site is a valid source of technical scientific information (this will determine whether your site is acceptable, so complete it carefully and completely):

  • This is a from the Great Lakes WATER Institute.
    • Wisconsin Aquatic Technology and Environmental Research
  • The site is copyrighted from UWM and written by a scientist who has a Ph.D.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Internet Source Worksheet

 

Most Internet sites are not appropriate references for academic work.  The purpose of this form is to allow you to provide evidence that your Internet source is a valid source of technical scientific information.  If this form is incomplete or unconvincing, your Internet source will not be accepted.  DO NOT complete this form if you used an electronic database to retrieve a copy of a scientific journal article.

 

Title of Web Site: Cladophora Abundance and Physical/Chemical Conditions in the Milwaukee Region of Lake Michigan

 

 

Website URL: http://v3.mmsd.com/AssetsClient/Documents/waterqualityresearch/cladophora_report2.pdf 

 

 

 

Author of Web Site (must have an author, can be an organization such as the Wisconsin Department of Natural Resources):

 Dr. H Bootsma and the Milwaukee Metropolitan Sewerage District

 

 

Last update of site (must be within 5 years):

2005

 

 

Evidence that the site is a valid source of technical scientific information (this will determine whether your site is acceptable, so complete it carefully and completely):

 

  • “This summary is derived from research conducted by Dr. H Bootsma and colleagues of the University of Wisconsin-Milwaukee

Great Lakes WATER Institute. Support and funding of this research was from the Milwaukee Metropolitan Sewerage District

(MMSD Contract # M03002P15)”

 

 

 

 

 

 

 

 

 

Self Assessment – Laboratory Report

Name:  Liann Liegler, Chantalle Carver, Erinne Sonnenberg                                                                        Lab Report #          Research Project

 

Student

 

Instructor

 

 

X

 

 

 

Turned in on time.  (If not, minimal feedback will be provided and there will be no revision opportunity.)

 

X

 

 

 

Cites at least 2 technical scientific references (3 for project report).  No textbooks or encyclopedias, Internet Source Worksheet provided for any web sites. 

 

X

 

 

 

Citation format is correct.   Example: (Smith 2007).

 

X

 

 

 

Includes a list of literature cited in correct format.

 

X

 

 

 

Abstract briefly says what you did and found.

 

X

 

 

 

Introduction sets context and states hypothesis.

 

X

 

 

 

Methods clearly state what you did.

 

 

X

 

 

 

Results include sentences to describe major findings, a computer-generated graph, summary statistics, and a statistical test. 

 

X

 

 

 

Discussion explains your findings and relates them to what is already known. Describes any changes you would make.


X

 

 

 

Follows the conventions described in “Guide to Writing in Biology”

(metric units, scientific name used correctly, etc.).

 

Did you look at the example and/or read the directions in the syllabus? Yes

Did you use Turnitin.com? Yes

 

List at least one strength and one weakness in this report:

 

One strength was in our methods.  We took samples from a variety (4) of beaches on four different occasions.  This gave us a large sample size.  We did this hoping to make our results more accurate

 

Instructor comments: