Barrie Creeks, Lovers Creek, and Hewitt's Creek Subwatershed Plan

The Barrie Creeks, Lovers Creek and Hewitt’s Creek Subwatershed Plan
Long Term Trends at Site LOV101 of Lovers Creek
Site LOV101 is the monitoring site closest to the mouth of Lovers Creek. Data has been
collected at this site since 2002 and is available up until 2010. Long term trends are available for
IBI scores from 2003 to 2010, the correlation of effort spent versus amount of mottled sculpin
captured (2003-2010) and the comparison of Hilsenhoff versus EPT (the difference between the
Hilsenhoff and EPT index is that Hilsenhoff is an index that uses all the family groups of insects
to evaluate the organic pollution in a stream, while EPT uses Ephemeroptera, Plecoptera and
Tricoptera – or shredders - as a percent of the entire sample of invertebrate to assess health)
trends from 2002 to 2010.
Figure 5-15 illustrates the long term IBI trends for Site LOV101. Based on the score rating
mentioned previously, it can be seen that on average the site has a ‘fair’ rating. In 2003 and
2007, it had a rating of good. In 2005 though, there was a noticeable drop in the ecological
integrity of the site down to a ‘poor’ rating. During this year, the fish community had low
diversity, no top predators, no brook trout and an overall low abundance of fish.
Figure 5-15: Lovers Creek IBI Scores for Site LOV101 (2003 - 2010).
While long term data was not available for brook trout (the
only record is one caught in 2010), it was for mottled
sculpin, which are also a cold water species and occupy
habitat similar to that used by brook trout. When years of
data are compared, it is expected that with increased effort
spent to capture fish there is a corresponding increase in
the amount (weight) of fish caught. Changes in the
community are indicated when effort increases but weight
decreases (indicating that mottled sculpin populations have
decreased) or when effort decreases and weight increases
(indicating that mottled sculpin populations have
increased). In 2006, the effort spent electrofishing
increased but the overall weight of all the fish caught
Mottled sculpin
(Cottus bairdi)
decreased, suggesting that populations had dropped that year. In 2008 and 2009, there was a
decrease in effort and an increase in weight, suggesting that whatever decrease was seen two
years prior had rebounded (Figure 5-16).
Chapter 5: Aquatic Natural Heritage 248