Biodiversity Canada Sask.
Biodiversity 2
Living Fossil??
Identification, Taxonomy papers
Environmental Laws, Canada
Species of Concern
Oldman Dam Alberta
Alberta Update 2010
Saskatchewan Update
Saskatchewan River
Saskatchewan River Detail Descriptive
Background Concepts of River Ecology
 Communities, species, origins, distribution
 Rare and Endangered Accounts
Additional species of interest
Current status and conditions
Mystery of St. Louis 06
The River at Saskatoon
Lemsford Ferry
Communities Natural and Altered River
Dams,Research Thermal
 Research Nutrients and Eutrophication
Blackfly Research
undisturbed sites, a comparison
Aquatic Insects
Oregon Winter Ponds
Oregon Rivers Intro
Willamette River
Columbia River
Missouri River
China Yangtze River
Arctic Canada, Rankin
MacKenzie River Canada
Fish- Rivers
Teaching Materials


An overview of the Saskatchewan River:

thermal rare enrich landscape.pdf

Notice:  The following data are unpublished in regular journals.  If any information is used from this page or these pdf's, please credit Rie Miyazaki in particular and also this website as the source and owners of the data.  Thank you.-


    The map at left and the table below illustrate the condition of insect communities in  the South Saskatchewan River.  The river flows from the west to the northeast.  

      Going from B to G, that is, from the Alberta border past Saskatoon to the confluence of the North and South Rivers, total insects in a standard set of samples goes from 1280 at B,  to zero  at D; totals then rise to 1840 at E, and drop to 133 at F-G.  Numbers then rise  to 767 near G. 

      Species composition and dominance are altered.  At E, Outlook Bridge, imost nsects in the samples  are Chironomidae, in contrast to other sites.  The highest numbers of species are at B and G.   Between B  and G number of species is lower, including reduction to zero at D.  The obvious explanations for negative conditions between B and G are Gardiner Dam and Saskatoon domestic and light industrial effluents.  Details of species samples are given in the PDF's below.
LocationBDEF-Gnear G
LemsfordOutletOutlook BridgeSt. LouisWeldon  Ferry
Total Insects124801840133767
Total species18013820
Total Chironomidae214011922954
Total Mayflies725020384512
Total Mayfly species1109611

Location B,  Lemsford Ferry, low levels of pollution.

Lemsford Ferry, near the Saskatchewan/Alberta border, has little in the way of visible sources of  pollution or alteration of the environment- -no city sewage, no pulp mills, etc.  However, in recent years I have noticed signs of nutrient enrichment- unusual amounts of bluegreen and other algae, plus new macrophytes compared to past years (I have been collecting at this site since 1970).  Lemsford Ferry has probably the most interesting community in the system in my experience- being a good site to collect most of the species on the Rare and Endangered Accounts page.  The pdf below shows result from July 2006 samples.

Lemsford transect July 2006 RCC.pdf edited 09.pdf

Lemsford Ferry is at site B.

 Between C and D- Diefenbaker Lake, no river species are present in lake.

Location D- outlet of Gardiner Dam.  No insects were present at D.                    

Site E, Outlook Bridge, downstream from Gardiner dam outlet.

outlook bridge july 06 edited 09.pdf

At Outlook Bridge, the total mayflies in the samples was 203, and 174 were Baetis tricaudatus.  Thus, diversity and community complexity were very low  compared to Lemsford Ferry.  Traverella, Lachlania, Isonychia, and other genera were absent at Outlook Bridge, but present at Lemsford Ferry.

At Outlook Bridge, total insects numbered 1466, and of these 1192 were Chironomidae.      At Lemsford Ferry, total insects numberred 1248, and of these, 214 were Chironomidae.  In general, Chironimidae are indicators of pollution or abnormal conditions.  Baetis tricaudatus, above paragraph, is widespread and a tolerant species, and appears to tolerate conditions at  Outlook Bridge, but many other species present at Lemsford Ferry are not present.)

About half way between F. and G. is St. Louis Bridge.  This area is in the path of the altered thermal regine from Gardiner Dam as well as more or less unknown industrial and municipal impacts from Saskatoon small industry and waste discharges.  

St Louis july 2006 edited 09 2.pdf

At St.Louis (between F-G), total insects were133, and 31 were Chironomidae.                   

At Outlook Bridge, total insects numbered 1466, and of these 1192 were Chironomidae.     

At Lemsford Ferry, total insects numberred 1248, and of these, 214 were Chironomidae.

  In general, Chironimidae are indicators of pollution or abnormal conditions.  Diverstiy and abundance in aquatic insect communities dropped drastically from B to D to E to F half way to G.



Weldon Ferry is near site G.

The diversity, number of species, and balance among taxonomic groups  at G. is perhaps more similar to Lemsford Ferry, B, than the sites between, which have zero insects in one case, dominance of Baetis tricaudatus and Chironomidae in another case, and a reduced fauna in the third case.  See table at the top of this page.

Weldon Ferry July 2006 edited 09 2.pdf

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