Owl River Riparian Restoration
and Enhancement Project:
Monitoring Report I
Tyler Johns and Stefanie Fenson
Since 2006, the Government of Alberta has stocked Lac La Biche with nearly 200 million
walleye fry to restore populations, and many of these walleye are expected to begin
spawning within the next few years. The Owl River is identified as the primary
spawning habitat for Lac La Biche walleye. However, agricultural activities in the area
have reduced riparian vegetation, and these activities could potentially increase
nutrient and sediment loading of the watercourse. The resulting reduction in water
quality could directly impact walleye spawning habitat, thereby potentially limiting the
success of the Lac La Biche walleye restoration program.
In 2011/12, we began a long-term project to protect and restore riparian habitat along
the Owl River. We collected baseline data on riparian health, water quality, aquatic
habitat, and the distribution of walleye spawning habitat. In 2014, we reassessed these
characteristics as part of a three-year interval monitoring protocol. Our study area
extended 40 km upstream from the mouth of the river at Lac La Biche and included a
portion of the Piche River. We also conducted surveys in the spring of 2012 and 2014 to
determine abundance of the walleye spawning run from the lake into the Owl River.
In 2011 and 2014, we observed several fish, including walleye and white suckers, in the
upstream 10 km section of the study area but very few fish in the downstream 30 km
section. Congregation of walleye in the upstream section confirms Alberta Environment
and Sustainable Resource Development’s (ESRD) identification of this section of the
river as suitable walleye spawning grounds. The dominant substrate of sites in the
upper section consisted of boulders, cobble and gravel suitable for walleye spawning,
whereas sites in the lower section consisted mainly of fines and sands not suitable for
walleye spawning. Overall, bank disturbance (erosion, exposed soil, human
disturbance) along the river was low, with grasses, sedges and woody shrubs
dominating the vegetation. These habitat characteristics were similar in 2011 and 2014.
We captured a total of 998 walleye during spring 2014, nearly 88% of which were in a
spawning stage (i.e., ripe or spent), confirming use of the Owl River as a walleye
spawning system. Overall, the total walleye capture was much lower in 2014 than in
2012. Walleye ranged in size from 435 to 677 mm total length (TL), with a mean
(± standard error) of 564.2 ± 2.3 mm (n = 583). Size of males ranged from 435 to
677 mm TL, with a mean of 542.8 ± 2.7 mm (n = 379), whereas females ranged in size
from 490 to 669 mm TL, with a mean of 609.3 ± 2.9 mm (n = 130). In general, females
were larger than males. Dominant size ranges were 560 to 620 mm for males and 600 to
660 mm for females, constituting 47% and 78% of the male and female catch,
Water temperature during the survey ranged from 5.3 to 12.9°C, with a mean of 9.2°C.
The number of walleye captured peaked on May 15, 2014, when water temperature was
10.5°C. We were unable to derive reliable abundance estimates of the walleye spawning
run due to unusually high water levels that influenced trap efficiency.
Dissolved oxygen was high (7.6 to 8.9 mg/L) throughout the river system from May to
August 2014. Overall, dissolved oxygen was similar in 2014 and 2011. In general, total
phosphorus (TP) concentrations were similar in 2014 and 2011. Total phosphorus
concentrations were high (summer average: 61.0 to 170.0 μg/L) throughout the system
and were highest at downstream sites. Based on TP values, the Owl River may be
considered as eutrophic to hyper-eutrophic. Total nitrogen concentrations ranged from
0.8 to 0.9 mg/L, slightly below the ESRD limit (1.0 mg/L). Total coliform counts were
high and exceeded the Canadian Council of Ministers of the Environment limit for
agriculture use (>1,000 mpn/100 mL) at all sites. We collected a total of 4,856
macroinvertebrates belonging to 35 families. The number of macroinvertebrates
collected in 2011 was more than double that collected in 2014. Diversity ranged from 1.2
to 1.7, and richness ranged from 13 to 21; there were no clear spatial distribution
patterns. The most common family was Baetidae (Order: Ephemeroptera).
Overall, riparian health conditions improved in 2014 relative to the baseline assessment
in 2011. We observed some indications of improved riparian health from poor to fair
condition, specifically in the areas where livestock exclusion fencing was installed in
2012. To date, we successfully renegotiated lease boundaries on eight quarter sections
with a leaseholder, and we installed over 7 km of wildlife-friendly livestock fencing,
effectively protecting over 8 km of important riparian habitat. Before moving forward
with further grazing lease withdrawal negotiations, local Alberta Public Lands staff had
requested that Alberta Conservation Association and ESRD work together to develop a
protective notation (PNT) application for the areas that have already been withdrawn.
We are working with ESRD to develop these PNTs.
In 2017/18, we will reassess riparian health, water quality, aquatic habitat, and the
distribution of walleye spawning habitat as part of our three-year interval monitoring
protocol. We will produce a final report on the project at this time.