Lake Sturgeon Project - United States Fish and Wildlife ... 2017-1 Annual Sturgeon Report...
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Lake Sturgeon Project
Little River Band of Ottawa Indians
Lake Sturgeon Project Report: LRBOI 2017-1
Annual Report of Lake Sturgeon Research and Reclamation Activities: 2016.
Photo of sturgeon being collected and removed from the river during nighttime sturgeon visual surveys for protection from sea lamprey treatment chemicals.
Suggested Citation:
LRBOI 2017. Annual Report of Lake Sturgeon Research and Reclamation Activities: 2016. Little River Band of Ottawa Indians Report 2017-1, Manistee, MI.
Prepared by: Corey Jerome, Fisheries Biologist
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Executive Summary:
The Little River Band of Ottawa Indians (LRBOI) Natural Resources Department has
intensively evaluated and managed the Big Manistee River lake sturgeon population for 15
years. The LRBOI sturgeon program aims to meet the goals and objectives of the Nmé (Lake
Sturgeon) Stewardship Plan which was implemented in 2007 (LRBOI 2008). A major element of
the plan, and thus the sturgeon program, is to use culturally derived principles along with
biological information during sturgeon restoration. The LRBOI operates a streamside rearing
facility (SRF) which integrates both of these elements; where young sturgeon are carefully
collected in the Big Manistee River and placed in rearing tanks where they are raised with natal
river water and released when large enough to experience higher survival (Holtgren et al.
2007). Rearing fish in their natal waters occurs to facilitate imprinting of the sturgeon so as
adults they will return to those waters to spawn and preserve the unique genetics of the
population (Welsh et al. 2010). Another program component is to monitor population status
including year-class recruitment, survival, and genetics through conducting nighttime visual
surveys. As with every year since 2003 the LRBOI held a ceremony in September where people
from the Manistee and regional community released streamside reared sturgeon by hand back
into the Big Manistee River. For each of the 13 release ceremonies the LRBOI and friends have
realized a major goal toward stewardship and are restoring the harmony and connectivity
between Nmé and the people and bringing them both back to the river.
Sturgeon Egg Collection:
Egg mats were set for the collection of lake sturgeon eggs on 25 April 2016 at Old Bridge
Pool in the Big Manistee River (Figure 1), the lower of two known spawning sites (Chiotti et al.
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2008). No mats have been set at an upper historic sampling site, Suicide Bend, since 2010
because of high angling pressure (Figure 1). Each set consisted of 20 cinder block egg mats set
in gangs of two (Chiotti et al. 2008). Egg mats were checked at least twice weekly Monday and
Thursday or three times weekly on Monday, Wednesday, and Friday. Egg mats were pulled
from the river on 23 May 2016. Forty (±0.00 SD) egg mats were deployed per day for a total of
672.25 hours of sampling. During this time there wasn’t any documentation of sturgeon
spawning at Old Bridge Pool. While the lack of documentation doesn’t mean that spawning
didn’t occur as sampling effort was limited due to limited staffing availability. In previous years
documented spawning has occurred as late as the 9th of June which was in 2014.
Larval Drift:
Larval drift was conducted for the 15th consecutive year at Sawdust Hole in the Big
Manistee River (Figure 1). Index nets have been set annually beginning in 2002 in order to
monitor and compare abundance of drifting larval sturgeon. Additional nets (SRF nets) are set
to increase abundance of larval sturgeon for rearing within the SRF. Drift surveys were
conducted between 26 May and 8 June with the first larvae captured on 30 May and the last on
2 June. The first larval drift event occurred from 30 May through 2 June. A second drift peak
was not observed this year, but the lack of documentation of a second drift doesn’t mean that
one didn’t occur because larval drift sampling was ended earlier than normal due to staffing
constraints. Larval lake sturgeon have been seen as late as 21 June and, second drift peaks have
been observed during 2003, 2005, 2007, 2010, and 2015. Abundance of larval sturgeon was
found at the third lowest amount in the 15years at 49 with the highest abundance occurring in
2010 at 726. Catch per unit of effort (CPUE) of larval sturgeon in index nets was 0.337 fish/net
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hour which was below the average of 0.491 (±0.437 SD) fish/net hour over the 15 year sampling
effort. Even though the total number of larval sturgeon captured during sampling was the third
lowest amount over the history it was the 8th highest CPUE throughout sampling because of the
shortened sampling period.
Sturgeon Visuals Index Surveys:
Visual surveys to capture Age-0 and Age-1 sturgeon have been conducted since 2003.
Since 2008 location of survey sites have been standardized using nine fixed index sites (Mann et
al. 2011) that extend from Rainbow Bend to High Bridge Road (Figure 3); though for the 2016
sampling season only eight index sites were sampled. Visual surveys are conducted using a
boat and slowly motoring upstream while scanning the river bottom with spotlights. Index sites
were surveyed once on 22nd August and 14-15 September. During the August survey total of 13
age-0 and one age-1 wild lake sturgeon were captured with length averaging 192 mm TL (±12.8
SD) and 360 mm TL. Fish encountered during the August survey were removed from the river
and held in the SRF until after the completion of a sea lamprey treatment. All index sites were
sampled on the same night to limit a bias in sampling due to the removal of the sturgeon from
the system. For more details on the removal and sea lamprey treatment assessment see section
titled: Sturgeon Visual Surveys/removal in Conjunction with Sea Lamprey Treatment. Visual
surveys CPUE was calculated across sites for August 2016 was 1.44 (±3.6 SD) which is slightly
lower than the August average from 2008-2016 of 1.64 (±2.7 SD) during 2008-2016 (Table 1).
The standard deviation is larger due to 11 of the 13 fish were captured within site 9. During the
September survey a total of 7 age-0 wild lake sturgeon were captured with length averaging
213 mm TL (±15.0 SD). Of the 7 fish captured on September 14 4 of them had been previously
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captured during earlier visual survey assessments. Limited number of sturgeon seen and the
high recapture rate during the September survey was probably highly affected by the sea
lamprey treatment.
Sturgeon Visual Surveys/removal in Conjunction with Sea Lamprey Treatment
The Manistee River was treated to reduce the number of larval sea lamprey on 29-30
August before they can transform and migrate to Lake Michigan for their parasitic life stage.
During past Sea Lamprey treatments on the Manistee and Muskegon Rivers it has been
determined that juvenile sturgeon are susceptible to mortality during these treatments. With
this new understanding a collaborative effort was put together to survey the Manistee River
the week leading up to the sea lamprey treatment for the collection and removal of juvenile
sturgeon to be held within the SRF until after the treatment was completed. The removal
nicknamed Save-Our-Sturgeon (SOS) was done with the aid of Michigan Department of Natural
Resources and US Fish and Wildlife Service.
Surveys were done nightly from 22nd through 28th of August and a post sea lamprey
treatment surveys done on 30th of August and 14th of September. During the pretreatment
surveys no assessments were done on the night of the 27th due to inclement weather. Total
number of crews on the water nightly ranged from 4 to 1 with an average of 3 crews surveying
nightly (Table 2). Assessment areas were focused on known locations where juvenile sturgeon
inhabit based on the above detailed indexed sites. Additional areas were sampled within the
river where conditions allowed sampling and habitat seemed conducive to sturgeon use.
A total of 117 sturgeon were removed from the Manistee River and held in the SRF
through the duration of the sea lamprey treatment. Fish were kept separated based on river
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section of collection to aid in the release back into the river. The majority of the sturgeon (62)
came from the middle section of the river between the landmarks of Orchard’s Landing and
Ebel’s (Table 3, Figure 4).
During the time the treatment chemical was in the river the SRF stopped pulling fresh
river water into the facility and was put on a closed loop. During this time an issue was noted
within the facility when three wild collected and one SRF reared fish were observed dead. The
issue was remedied by stopping the recirculation of the closed loop water and increased
aeration of the water within the tanks. Shortly after making the changes fish behavior seemed
to become more normalized than when the system was circulating. The majority of sturgeon
were released back into the Manistee river on the 1st of September within the same river
sections of capture. Seven sturgeon were held until September 17th when they were released
during the annual sturgeon release ceremony. These few fish were captured in the stretch of
river where the release ceremony is held and since the facility didn’t produce any sturgeon for
the rearing season were used for a representation of the work done towards sturgeon recovery
for the 2016 season.
A post sea lamprey treatment assessment was conducted on 30th of August and 14th of
September with 4 crews on the river sampling the same river sections as were sampled
pretreatment. The September 14th assessment was also a part of standard index sampling as
mentioned above with additional river segments sampled that is outside of the indexed
protocol sampling. Therefore there are some differences in capture totals for the same night of
sampling. During the August post treatment survey a total of 13 dead sturgeon were sampled
with one live age-0 sturgeon sampled. The one live lake sturgeon that was sampled post
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treatment was also sampled during the September index visual survey meaning that it had
survived weeks past the treatment. An additional 3 fish during the September post treatment
survey were new fish that hadn’t been sampled previously. A total of 15 fish were captured
during the September post treatment assessment. This might mean that if a sturgeon can
survive through the sea lamprey treatment that they are likely to survive long term, but it is
unknown if there are any long term effects of the treatment on these individuals. The post
treatment assessment in August was limited in duration due to inclement weather that came in
around midnight. The assessment was limited to searching the river to areas that the river
bottom is visible unlike typical sturgeon visual surveys this post treatment assessment dead
sturgeon could be found in all types of habitat due to them tumbling in the river current. Some
dead sturgeon were found trapped along logs and vegetation while others were actively
tumbling down river in the current. Additional dead sturgeon were probably missed if they
were trapped in deeper water or obstructions that would limit observations.
SRF Sturgeon Rearing:
Larvae (wild captured) were reared in fry tanks and raceways, depending on size
(Holtgren et al. 2007). Fish were fed a diet of brine shrimp Artemia franciscana and chironomid
larvae. During larval drift 49 larvae were brought into the SRF for rearing until fall when they
are released during an annual release ceremony. This year during the rearing of the larval
sturgeon there was an unknown die off of larvae that resulted in the majority of larval sturgeon
dying during a 5 day period in the middle of June. Some mortality has been noted in past
rearing years around this timeframe but total numbers of larval sturgeon in the facility have
buffered the lost. With a limited number of larval to start the rearing year with this mortality
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event resulted in there being only one sturgeon that was being reared in the SRF. The
remaining sturgeon was involved in a mortality event during the recirculation of water in the
SRF during the sea lamprey treatment. If not for this mortality event that was a mechanical
issue the sturgeon should have made it till the annual sturgeon release. This was the first year
in the history of operating the SRF that there has been a complete loss of larval lake sturgeon
brought in from eggs or drift. Corrective actions have been made to limit adverse effects from
mortality events and mechanical issues going forward. While the SRF has been put into a
recirculation before this year a new slightly larger water pump was used which is believed to
have caused the introduction of increased gasses within the water. For future recirculation
setups a smaller pump will be used since the recirculation is for short term a smaller pump can
be used without issues with it failing and not increasing gasses within the water.
As mentioned in the above section 117 wild sturgeon were brought into the SRF for a
short period of time due to the river being treated for sea lamprey. Most of the fish were
released back into the Manistee River after the treatment was completed, while seven fish
were held for an additional two weeks to be a part of the annual sturgeon release ceremony.
Genetic Analysis:
Genetic samples of streamside reared and wild captured Big Manistee River lake
sturgeon from 2005-2014 were analyzed by Michigan State University. Outcomes of the
analysis include understanding the parental contribution of spawning sturgeon and an estimate
of the effective spawning site. Genetic estimates show that the effective adult population size
over the 10 year period was ~137 and the total number of adults contributing to larvae
captured was ~347. Within each spring spawning the estimate of effective number of breeding
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adults was fairly constant but relatively low ranging from 17-48. The estimates of effective
number of adults are slightly above the recommended restoration goals for a single annual
cohort of hatchery-reared juveniles (Ne~20; Welsh et al. 2010). The full report titled 2005-2014
LRBOI Manistee River Sturgeon report is an unpublished internal document to help guide
management practices and assess progress towards the restoration of the Manistee Lake Sturgeon
population.
Public Outreach:
SRF tours occurred throughout the season as interested citizens would stop at the
facility while staff was onsite. Staff would take the time to explain the current stages of growth
and collection methods, daily procedures, and mention the release ceremony.
A few new releases were published about the efforts put forward towards the
protection of juvenile sturgeon during the sea lamprey treatment. While some of the releases
focused on some of the negative effects on salmonids during the sea lamprey treatment they
included the positives that were seen from removing sturgeon from the river so that they
weren’t exposed to the chemical treatment.
Several newspaper articles covered the LRBOI sturgeon program, including the Rapid
River News (weekly LRBOI news), the Currents (LRBOI monthly paper), and local and regional
newspapers.
Great Lakes Juvenile Indexed Assessments
Since 2013 LRBOI has been conducting juvenile sturgeon assessments with targeted
sampling efforts around the mouth of the Manistee River in Lake Michigan and in 2016 the
Muskegon River mouth was added to the assessment. Sampling effort is 2 sets within each
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zone of 0-2 km (inner zone), >2-5 km (middle zone), and >5-10 km (outer zone) from the
tributary mouth. Each set consists of two gangs of gill nets to form a continuous net of 304.8 m
containing stretch mesh of 11.4, 20.3, and 25.4 cm. Sets are left for 24 hours or one net night
with CPUE reported as number of fish per net night per 304.8 m of net.
Sampling at the Manistee River mouth was done on September 19th and 28th with 4 net
sets being able to be completed the 5th and 6th set didn’t occur due to inclement weather
during the sampling period that didn’t allow for the boat to get out. Sets were done with one
net in the inner zone, two in the middle zone, and one in the outer zone. Surface water
temperature ranged from 20-17.2°C and net set depths of 3.9-9.5 m. Three sturgeon were
sampled during the 2016 assessment two from the inner zone set and one from a middle zone
set (Figure 5). Sturgeon lengths were 406, 762, and 413 mm. Bycatch has been limited with this
assessment to under 25 fish total per net and hasn’t caused any concerns to need to change
sampling protocol to limit bycatch. None of the sturgeon were recaptured fish so they received
a PIT tag and were released in good health. CPUE for the 2016 assessment was .75 fish per net
night/set.
During October third and fourth test assessment was conducted at the Muskegon River
mouth with four nets set with one net in the inner zone, two nets in the middle zone, and one
net in the outer zone. Since this was an exploratory sampling a second set within the inner and
outer zone weren’t completed with this sampling effort, but if continued in future years
sampling effort would be equal across all zones. Water temperatures during ranged from 16.1-
17.2°C and net set depths of 4.4-7.7 m. During this test assessment nine sturgeon were
sampled with five in the inner zone, four in the middle zone, and zero in the outer zone (Figure
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6). CPUE for sturgeon was 2.25 fish per net night/set. Unlike the Manistee River mouth
assessment the bycatch at the Muskegon River mouth was very high and causes concerns to
the ability to continue the assessment in future years. Bycatch consisted of sucker species,
walleye, freshwater drum, and catfish. The difference in bycatch is hard to know if it is because
of a difference in location and productivity as the capture of sturgeon were also increased over
the Manistee location. Sampling protocol will have to be monitored in the future in relation to
bycatch if it remains high an alternative sampling protocol may have to be implemented. One
example could be instead of a 24 hour net set could be a 10-12 hour net set as has been done
at other sampling locations in Lake Michigan with high bycatch rates.
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Citations: Chiotti, J. A., J. M. Holtgren, N. A. Auer, and S. A. Ogren. 2008. Lake sturgeon spawning habitat in the Big Manistee
River, Michigan, USA. North American Journal of Fisheries Management 28:1009-1019.
Holtgren, J. M., S. A. Ogren, A. J. Paquet, and S. Fajfer. 2007. Design of a portable streamside rearing facility for
lake sturgeon. North American Journal of Aquaculture 69:317-323.
Holtgren, J. M. 2013. Bringing us back to the river, pp. 133-146 In N. Auer and D. Dempsey [eds.], The Great Lake
Sturgeon. Michigan State University Press, East Lansing, Michigan.
Mann, K.A., J. M. Holtgren, N. A. Auer and S.Ogren. 2011. Comparing size, movement and habitat selection of wild
and streamside-reared lake sturgeon. North American Journal Fisheries Management. 31(2):305-314
Mitchell, J. 2013. N'me, pp. 21-26 In N. Auer and D. Dempsey [eds.], The Great Lake Sturgeon. Michigan State
University Press, East Lansing, Michigan.
LRBOI (Little River Band of Ottawa Indians). 2008. Nmé (Lake Sturgeon) stewardship plan for the Big Manistee
River and 1836 reservation. LRBOI Natural Resources Department, Special Report 1, Manistee, Michigan.
LRBOI. 2013. Mortality of Age-0 Lake Sturgeon Post-Sea Lamprey Treatment in the Big Manistee River, Michigan.
LRBOI Natural Resources Department, Special Technical Report August 2013, Manistee, Michigan.
Welsh, A., R. Elliott, K. Scribner, H. Quinlan, E. Baker, B. Eggold, J. M. Holtgren, C. Krueger, and B. May. 2010.
Genetic guidelines for the stocking of lake sturgeon (Acipenser fulvescens) in the Great Lakes basin. Great
Lakes Fishery Commission, Miscellaneous Publication 2010–01, Ann Arbor, Michigan.
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Table 1. Sturgeon Visual Sites captures for August (# sturgeon/survey reach) 2008-2016 (n=1).
Index Site 2008 2009 2010 2011 2012
2013 2014
2015
2016
1 0 0 0 8 4 1 0 0 0 2 0 0 3 1 2 1 2 0 1 3 0 0 2 1 1 3 2 1 0 4 0 1 17 3 2 1 1 8 0 5 0 0 2 0 1 0 3 1 0
6 0 0 0 0 0
0
0 Not
Sampled
0 7 0 0 7 2 2 0 6 2 0 8 2 0 2 1 1 1 1 3 1
9 3 0 3 0 3 2 4 1 11
Total 5 1 36 14 16 9 19 16 13
Table 2. Sturgeon Visual surveys date, survey crews and total sturgeon collected before the sea lamprey treatment.
Date Survey Crews
Sturgeon collected
22-Aug 3 15 23-Aug 4 15 24-Aug 3 37 25-Aug 3 27 26-Aug 3 15 27-Aug 0 0 28-Aug 1 8
Table 3. Sturgeon visual surveys distribution of sturgeon collected before the sea lamprey treatment
Distribution of collections (downstream to upstream) Sturgeon Collected
Below Rainbow Bend 1 Rainbow Bent up to Bear Cr. 5 Bear Cr. up to Orchards Landing 24 Orchards Landing up to Ebel’s (below Blacksmith Landing) 62 Below Blacksmith Landing to 1 mile above Highbridge 25
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Figure 1. Big Manistee River with lake sturgeon sampling locations.
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Figure 2. Timing of lake sturgeon spawning within the old bridge pool of the Manistee river from 2006-2016. No documentation of LAS spawning occurred in 2016, but sampling was cut short due to staffing complications. X-axis is month/day.
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Figure 3. Big Manistee River visual survey index sites.
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Figure 4. Manistee River landmark names used when describing stretches of river for sturgeon visual survey fish
removals.
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Figure 5. Lake sturgeon sampled at the Manistee River mouth during index netting by zone and year sampled.
Figure 6. Lake sturgeon sampled at the Muskegon River mouth during test assessment of index netting by zone for
2016.
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2013 2013 2013 2014 2014 2014 2014 2014 2015 2015 2015 2016 2016 2016
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2016 2016 2016
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