North Temperate Lakes
US Long-Term Ecological Research Network

Lake Mendota, Wisconsin, USA, Phytobenthos Abundance and Community Composition 2016-2018

Abstract
We sampled the phytobenthos (epibenthic periphyton) of Lake Mendota from 2016-2018 to track impacts of invasive zebra mussels (Dreissena polymorpha) which were discovered in Lake Mendota in 2015 and grew exponentially to densities greater than 10,000 m-2 in shallow, rocky habitat by 2018. We sampled along three transects inherited from Karatayev et al. (2013) at five different depths (1, 3, 5, 8, and 10 m) twice a summer (June and August) from 2016-2018. A pared-down version of this routine sampling continued from 2019 onward but is not included here. This dataset complements zebra mussel and zoobenthos data collected according to the same routine sampling structure, for which data is also archived with EDI.
Core Areas
Dataset ID
391
Data Sources
Date Range
-
Methods
We sampled phytobenthos twice a summer (early June and late August) from 2016-2018 at five depths (1, 3, 5, 8, and 10m) along three transects running perpendicular to shore (A-C, Fig. 1). We collected triplicate samples at each site. SCUBA divers retrieved one rock at rock-dominated sites, or a petri dish full of undisturbed sediment at sand- and muck-dominated sites, and transported samples to the surface in a resealable plastic bag. In the laboratory, we scrubbed phytobenthos from rocks with a brush or emptied petri dish contents into a beaker. We separated phytobenthos from inorganic material by adding ~1 L of deionized water, homogenizing the sample, allowing settlement of inorganic material, and decanting the suspended phytobenthos. We kept samples dark and refrigerated until completely processed to prevent cell division after collection. <br/>We sampled phytobenthos twice a summer (early June and late August) from 2016-2018 at five depths (1, 3, 5, 8, and 10m) along three transects running perpendicular to shore (A-C, Fig. 1). We collected triplicate samples at each site. SCUBA divers retrieved one rock at rock-dominated sites, or a petri dish full of undisturbed sediment at sand- and muck-dominated sites, and transported samples to the surface in a resealable plastic bag. In the laboratory, we scrubbed phytobenthos from rocks with a brush or emptied petri dish contents into a beaker. We separated phytobenthos from inorganic material by adding ~1 L of deionized water, homogenizing the sample, allowing settlement of inorganic material, and decanting the suspended phytobenthos. We kept samples dark and refrigerated until completely processed to prevent cell division after collection.
Related Sites
Version Number
1

Madison community science field campaign to assess abundance and distribution of invasive jumping worms.

Abstract
Asian pheretimoid earthworms of the genera Amynthas and Metaphire
(jumping worms) are leading a new wave of co-invasion into
Northeastern and Midwestern states, with potential consequences for
native organisms and ecosystem processes. However, little is known
about their distribution, abundance, and habitat preferences in urban
landscapes – areas which likely influence range expansion via
human-driven spread. We led a participatory field campaign to assess
jumping worm distribution and abundance in Madison, Wisconsin in
September of 2017. By compressing 250 person-hours of sampling effort
into a single day, we quantified presence and abundance of three
jumping worm species across different land-cover types (forest,
grassland, open space, residential lawns and gardens), finding that
urban green spaces differed in invasibility. We show that community
science can be powerful for researching invasive species while
engaging the public in conservation. This approach was particularly
effective here, where broad spatial sampling was required within a
short temporal window.
Core Areas
Dataset ID
387
Date Range
LTER Keywords
Methods
At each study site, teams visually surveyed the area for signs of
jumping worm presence, including live organisms or the characteristic
granular soil signature indicative of their activity. For example, in
a residential yard, participants would walk through the space for
approximately 10 minutes, brushing aside leaf litter and checking
underneath planters or landscaping cloth (where the species are
anecdotally known to congregate) for live earthworms, and examining
garden soil for structural characteristics. Next, earthworms were
censused at three haphazard locations using a 30cm x 30cm quadrat and
a standard mustard extraction (Lawrence and Bowers 2002). Any
suspected jumping worms found were collected and returned to the
laboratory for visual identification following the field campaign. We
identified jumping worms to species (A. tokioensis, A. agrestis, M.
hilgendorfi) when possible (Chang et al. 2016a). Participants also
recorded the presence/absence of any additional (European) earthworm
species observed during sampling.
<br/>
NTL Themes
Related Sites
Version Number
1

Application of eDNA as a tool for assessing fish population abundance, Northern Wisconsin, US, 2017 - 2018

Abstract
Environmental DNA concentrations, WDNR/GLIFWC mark-recapture population estimates, and
abiotic lake data on 24 lakes in Wisconsin's Ceded Territory used to evaluate the
relationship between walleye abundance and environmental DNA density and its application as
a fisheries management tool. <br/>
Core Areas
Dataset ID
383
Date Range
-
Methods
Each lake was sampled in nine locations. Each sample received four qPCR replicates.
Each lake was accompanied by a field (FLD), filter (FIL), and qPCR no template control
(NTC) blank. Lakes with eDNA samples extracted together in a batch share the extraction
(EXT) blank. Lakes listed without extraction blanks take the previous lake's extraction
blank in the order listed in the data. <br/> Each lake was sampled in nine locations. Each sample received four qPCR replicates.
Each lake was accompanied by a field (FLD), filter (FIL), and qPCR no template control
(NTC) blank. Lakes with eDNA samples extracted together in a batch share the extraction
(EXT) blank. Lakes listed without extraction blanks take the previous lake's extraction
blank in the order listed in the data. <br/> Each lake was sampled in nine locations. Each sample received four qPCR replicates.
Each lake was accompanied by a field (FLD), filter (FIL), and qPCR no template control
(NTC) blank. Lakes with eDNA samples extracted together in a batch share the extraction
(EXT) blank. Lakes listed without extraction blanks take the previous lake's extraction
blank in the order listed in the data. <br/>
NTL Themes
Version Number
1

North Temperate Lakes LTER: Trout Lake Spiny Water Flea 2014 - present

Abstract
Beginning in 2014, 30 meter vertical tows with a special zooplankton net were collected in Trout Lake specifically for the invasive Bythotrephes longimanus (spiny water flea). The net has a 400 micrometer mesh with a 0.5 meter diameter opening. Individuals are simply counted, and density is determined to be the number of individuals divided by the total water volume of each tow.
Additional Information
Related data set: North Temperate Lakes LTER: Zooplankton - Trout Lake Area 1992 - current (37)
Core Areas
Dataset ID
389
Date Range
-
Maintenance
on-going
Methods
Two 30-meter vertical tows (0.5m diameter, 400um mesh net) are collected at the deepest part of Trout Lake each time the lake is visited for routine LTER sampling during open water. On occasion, tows are collected on additional dates. Samples are visually scanned in their entirety for number of Bythotrephes present. The samples are not preserved or archived.

Publication Date
Related Sites
Version Number
2

North Temperate Lakes LTER Regional Survey Zooplankton 2015 - current

Abstract
The Northern Highlands Lake District (NHLD) is one of the few regions in the world with periodic comprehensive water chemistry data from hundreds of lakes spanning almost a century. Birge and Juday directed the first comprehensive assessment of water chemistry in the NHLD, sampling more than 600 lakes in the 1920s and 30s. These surveys have been repeated by various agencies and we now have data from the 1920s (UW), 1960s (WDNR), 1970s (EPA), 1980s (EPA), 1990s (EPA), and 2000s (NTL). The 28 lakes sampled as part of the Regional Lake Survey have been sampled by at least four of these regional surveys including the 1920s Birge and Juday sampling efforts. These 28 lakes were selected to represent a gradient of landscape position and shoreline development, both of which are important factors influencing social and ecological dynamics of lakes in the NHLD. This long-term regional dataset will lead to a greater understanding of whether and how large-scale drivers such as climate change and variability, lakeshore residential development, introductions of invasive species, or forest management have altered regional water chemistry. Zooplankton samples were taken at approximately the deepest part of each lake, via a vertical tow with a Wisconsin net. Count of individuals and presence absence data for all lakes in the study region are provided here.
Contact
Core Areas
Dataset ID
381
Date Range
-
Maintenance
ongoing
Methods
One zooplankton sample was collected in June 2015 at the deepest part of each lake, via vertical tow with a Wisconsin net (20cm diameter, 80um mesh). Contents of the net were preserved in the field with cold 95% ethanol. Subsamples of each vertical tow sample were counted for zooplankton species, using enough volume to count at least 300 individuals. A larger volume was then visually scanned to look for presence of additional species not seen in the count volume, until at least 2000 individuals had been seen.

Version Number
1

Wisconsin creel dataset as well as predictor variables for lakes from 1990 to 2017 to estimate statewide recreational fisheries harvest

Abstract
Recreational fisheries have high economic worth, valued at $190B globally. An important, but underappreciated, secondary value of recreational catch is its role as a source of food. This contribution is poorly understood due to difficulty in estimating recreational harvest at spatial scales beyond an individual system, as traditionally estimated from angler creel surveys. Here, we address this gap using a 28-year creel survey of ~300 Wisconsin inland lakes. We develop a statistical model of recreational harvest for individual lakes and then scale-up to unsurveyed lakes (3769 lakes; 73% of statewide lake surface area) to generate a statewide estimate of recreational lake harvest of ~4200 t and an estimated annual angler consumption rate of ~3 kg, nearly double estimated United States per capita freshwater fish consumption. Recreational fishing harvest makes significant contributions to human diets, is critical for discussions on food security, and the multiple ecosystem services of freshwater systems.
Contact
Core Areas
Dataset ID
379
Date Range
-
Maintenance
completed
Methods
The state of Wisconsin is comprised of about 15,000 inland lakes ranging from 0.5 to 53,394 ha (WDNR 2009). Most lakes occur in the northern and eastern part of the state as a result of glaciation. about 3,620 lakes are greater than 20 ha and together comprise about 93% of the state's inland lake surface area (Wisconsin Department of Natural Resources 2009). Wisconsin lakes constitute a wide range of physical and biological characteristics. Wisconsin inland lakes support valuable recreational fisheries for a variety of species, including Walleye (Sander vitreus), Northern Pike (Esox lucius), Muskellunge (Esox masquinongy), Yellow Perch (Perca flavescens), Largemouth Bass (Micropterus salmoides), Smallmouth Bass (Micropterus dolomieu), Lake Sturgeon (Acipenser fulvescens), and a variety of sunfish species (Lepomis spp.).
Related Sites
Version Number
2

North Temperate Lakes LTER Zooplankton conversion formulas length to biomass

Abstract
Formulas for calculating zooplankton biomass based on measured length for species encountered in NTL's northern lakes. Formulas are either based on literature reports or measurements in particular research lakes.
Core Areas
Dataset ID
376
LTER Keywords
Maintenance
completed
Methods
formulas are based on data in literature or were determined in samples from research lakes:

Culver D.A. et.al. 1985. Can. J. Fish. Aquat. Sci. Vol 42, 1380-1390.
Biomass of freshwater crustacean zooplankton from length-weight regressions.

Downing, John A. and Frank H. rigler. 1984.
A manual on methods for the assessment of secondary productivity in fresh waters. Second edition.

Dumont, H.J., I. Van de Velde and S. Dumont. Ref??
The dry weight estimate of biomass in a selection of cladocera, copepoda and rotifera from the plankton, periphyton and benthos of continental waters.

Hawkins, Bethany E. and M.S. Evans. 1979. J.Great Lakes Res. 5(3-4):256-263
Seasonal cycles of zooplankton biomass in southeastern Lake Michigan

Lawrence, S.G., D.F. Malley, W.J. Findlay, M.A. MacIver and I.L. Delbaere. 1987. Can J. Fish. Aquat. Sci. 44: 264-274.
Methods for estimating dry weight of freshwater planktonic crustaceans from measures of length and shape.

Pace M.L. and J.D. Orcutt. 1981. Limnol. Oceanogr. 26(5), 822-830.
The relative importance of protozoans, rotifers, and crustaceans in a freshwater zooplankton community.

Yan N.D. and G.L. Mackie. 1987. Can. J. Fish. Aquat. Sci. Vol 44, 382-389.
Improved estimation of the dry weight of Holopedium gibberum using clutch size, a body fat index, and lake water total phosphorus concentration.

Ruttner-Kolisko A. 1977. Arch. Hydrobiol. Beih. Ergebn. Limnol. 8, 71-76.
Suggestions for biomass calculations of plankton rotifers.
Version Number
1

Cascade project at North Temperate Lakes LTER - Daily data for key variables in whole lake experiments on early warnings of critical transitions, Paul and Peter Lakes, 2008-2011

Abstract
Peter Lake's food web was altered by adding largemouth bass at a slow rate while monitoring key food web constituents including littoral minnow abundance indexed as catch per trap per hour, zooplankton biomass, and concentration of chlorophyll a. Paul Lake was manipulated and the same variables were measured there.
In Peter Lake, we expected littoral catch of minnows to first increase as minnows moved into the littoral zone due to the threat of bass predation and then decrease due to bass predation. We expected zooplankton biomass to increase as minnows moved into the littoral zone. We expected chlorophyll to decrease due to increased grazing by zooplankton. We expected that variance and autocorrelation of chlorophyll would increase as the food web passed a critical transition.
We expected that the time series in Paul Lake would represent the normal variability of an unmanipulated lake
Dataset ID
374
Date Range
-
Methods
Primary publications that provide more information about taxa, methods, and data are:
Carpenter, S.R., J.J. Cole, M.L. Pace, R.D. Batt, W.A. Brock, T. Cline, J. Coloso, J.R. Hodgson, J.F. Kitchell, D.A. Seekell, L. Smith and B. Weidel. 2011. Early warnings of regime shifts: A whole-ecosystem experiment. Science 332: 1079-1082.
Cline, T.J., D. A. Seekell, S. R. Carpenter, M. L. Pace, J. R. Hodgson, J. F. Kitchell, and B. C. Weidel 2014. Early warnings of regime shifts: evaluation of spatial indicators from a whole-ecosystem experiment. Ecosphere 5:art102. http://dx.doi.org/10.1890/ES13-00398.1
Pace, M.L., S.R. Carpenter, R.A. Johnson and J. T. Kurzweil. 2013. Zooplankton provide early warnings of a regime shift in a whole-lake manipulation. Limnology and Oceanography 58: 525-532.
For an explanation of our rationale and expected results see:
Carpenter, S. R., Brock, W. A., Cole, J. J., Kitchell, J. F., & Pace, M. L. 2008. Leading indicators of trophic cascades. Ecology Letters, 11(2), 128-138. doi:DOI 10.1111/j.1461-0248.2007.01131.x
Related Sites
Version Number
2

Production, biomass, and yield estimates for walleye populations in the Ceded Territory of Wisconsin from 1990-2017

Abstract
Recreational fisheries are valued at $190B globally and constitute the predominant use of wild fish stocks in developed countries, with inland systems contributing the dominant fraction of recreational fisheries. Although inland recreational fisheries are thought to be highly resilient and self-regulating, the rapid pace of environmental change is increasing the vulnerability of these fisheries to overharvest and collapse. We evaluate an approach for detecting hidden overharvest of inland recreational fisheries based on empirical comparisons of harvest and biomass production. Using an extensive 28-year dataset of the walleye fisheries in Northern Wisconsin, USA, we compare empirical biomass harvest (Y) and calculated production (P) and biomass (B) for 390 lake-year combinations. Overharvest occurs when harvest exceeds production in that year. Biomass and biomass turnover (P/B) both declined by about 30% and about 20% over time while biomass harvest did not change, causing overharvest to increase. Our analysis revealed 40% of populations were production-overharvested, a rate about 10x higher than current estimates based on numerical harvest used by fisheries managers. Our study highlights the need for novel approaches to evaluate and conserve inland fisheries in the face of global change.
Contact
Core Areas
Dataset ID
373
Date Range
-
LTER Keywords
Methods
All methods describing the calculation of these data can be found in Embke et al. (in review)
Version Number
1

Cascade project at North Temperate Lakes LTER - Daily Chlorophyll Data for Whole Lake Nutrient Additions 2013-2015

Abstract
Daily chlorophyll for surface water samples in Paul, Peter, and Tuesday lakes from mid-May to early September for the years 2013, 2014 and 2015. Inorganic nitrogen and phosphorus were added to Peter and Tuesday lakes each year while Paul Lake was an unfertilized reference.
Contact
Core Areas
Dataset ID
372
Date Range
-
Maintenance
completed
Methods
Methods are described in Wilkinson et al. 2018 (Ecological Monographs 88:188-203) and Pace et al. 2017 (Proceedings of the National Academy of Sciences USA 114: 352-357). These publications including supplements should be consulted for details.

Version Number
1
Subscribe to biological (all)

 

 

National Science Foundation | LTER Network | Center for Limnology        

This material is based upon work supported by the National Science Foundation under Cooperative Agreement #DEB-2025982, NTL LTER (ROR: 04gq8q482). Any opinions, findings, conclusions, or recommendations expressed in the material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.