US Long-Term Ecological Research Network

Biocomplexity at North Temperate Lakes LTER; Coordinated Field Studies: Predation Study Data 2000 - 2004

Abstract
These data were collected to track changes in dietary composition, changes in age and growth structure, and changes in species and size of prey of fish predators in Sparkling Lake, Vilas County, WI, USA. Sampling began in May of 2000 and ended in September of 2004. Fish were collected with a boat-mounted electrofishing system, usually by conducting a complete lap around Sparkling Lake shortly after dark. Commonly captured species were rock bass, smallmouth bass, and walleye. Less common species were pumpkinseed sunfish and yellow perch. Dietary Composition: Fish stomach contents were collected by gastric lavage, and fish were released after capture. Stomach contents were sorted and counted by major taxonomic groups, dried in polystyrene weighboats at 57 deg C for 48hrs, and then weighed to 0.001g. The count under a taxonomic group heading indicates how many individuals of that group were found in that diet sample. The mass of that group is given in the adjacent ''net wt'' column. Diets varied across sampling dates and years, with a trend towards decreased abundance of the exotics rusty crayfish and rainbow smelt and increased reliance on native minnows. Prey Data: Fish stomach contents were collected by gastric lavage, and fish were released after capture. Once collected, crayfish and fish prey were measured unless advanced digestion had occurred. If possible, the carapace, right chela and left chela of crayfish prey were measured . Due to digestion, it was usually not possible to get all three measurements. The total length of prey fish was recorded. Young-of-year smelt and crayfish were often too small or digested to measure; these were often just counted. Gut labels on each sampling date correspond with the same gut labels in other datasets. Prey fish and crayfish size and composition varied across sampling dates and years, with a trend towards decreased abundance of rusty crayfish and rainbow smelt and increased reliance on native minnows. Age Growth Data: Scale samples were taken from captured predator fish in the summers of 2000, 2001, 2002, and 2004. Number of sites: 1 - Sparkling Lake Sampling Frequency: 2000: twice; 2001-2004 weekly or biweekly
Core Areas
Dataset ID
128
Date Range
-
LTER Keywords
Maintenance
completed
Metadata Provider
Methods
please see abstract for methods description
Short Name
BIOROTH1
Version Number
7

Biocomplexity at North Temperate Lakes LTER; Coordinated Field Studies: Littoral Plots 2001 - 2004

Abstract
In 2001 - 2004 the abundance of coarse wood and other aspects of the physical structure of the littoral zone were surveyed along transects that followed the 0.5 m depth contour at 488 sites in Vilas County. These data were collected as part of the "cross-lake comparison" segment of the Biocomplexity Project (Landscape Context - Coordinated Field Studies). The study explored the links between terrestrial and aquatic systems across a gradient of residential development and lake landscape position. Specifically, this project attempted to relate the abundance of Coarse Wood in the littoral zone with abiotic, biotic and anthropogenic features of the adjacent shoreline. Each of the 488 sites was a 50 m stretch of shoreline. The transects started and ended at the beginning and end of the site; the length of each transect, therefore, varied. Logs which were at least 150 cm in length were counted; more detailed descriptions were taken of logs at least 10 cm in diameter and 150 cm long. Information on littoral and shoreline substrate was also collected. Sampling Frequency: each site sampled once Number of sites: 488 sites on 61 Vilas County lakes were sampled from 2001-2004 (approximately 15 different lakes each year; eight sites per lake).
Dataset ID
125
Date Range
-
Maintenance
completed
Metadata Provider
Methods
In 2001 - 2004 littoral habitat, fish and macrophyte surveys were performed at eight sites within each of the 55 lakes. The sites were chosen by randomly selecting two points per compass quadrant of each lake. Each year littoral habitat surveys were conducted in June, fish surveys in July and macrophyte surveys in August.Littoral habitat (substrate and coarse woody habitat) was measured along a 50 m transect parallel to shore along the 0.5 meter depth contour at each site. The two Littoral CWH variables (number of logs km-1 greater than 5 cm diameter, and number greater than 10 cm) were transformed by log of (1+number) to normalize the variables.
Short Name
BIOLPLOT
Version Number
7

Biocomplexity at North Temperate Lakes LTER; Coordinated Field Studies: Littoral Macrophytes 2001 - 2004

Abstract
The aquatic vegetation of 60 lakes selected for the "cross-lake comparison" segment of the Biocomplexity Project was surveyed during the month of August in years 2001 through 2004. The study lakes are located in Vilas County, Wisconsin and were chosen to represent a range of positions on gradients of both human development and landscape position. The purpose of the macrophyte portion of the "cross-lake comparison" study was to evaluate the roles of landscape position and human development in the presence and composition of macrophyte communities.
Core Areas
Dataset ID
127
Date Range
-
Maintenance
completed
Metadata Provider
Methods
The macrophyte surveys were performed at eight sites within each of the 60 lakes. The sites were chosen by randomly selecting two 50m segments of shoreline per compass quadrant of each lake. At each site, we examined the macrophytes to a depth of 2m along a 50 m long transect perpendicular to the shoreline, beginning at the center point of the 50m segment of shoreline selected for the site. Within a ? m2 quadrat at every meter mark, we noted the species present, the dominant species, the substrate composition and the total percent vegetation cover. If a depth of 2 m was reached before 20 quadrats were measured, a second transect was performed 25 m to the right of the initial point. The distances from shore at 1 m depth and 2 m depth were also recorded on each transect for an estimate of slope. Sampling Frequency: each site sampled once Number of sites: 60 Vilas County lakes were sampled from 2001-2004 (approximately 15 different lakes each year).At each site, we examined the littoral vegetation along a transect perpendicular to the shoreline. Within a 0.25 m2 quadrat at every meter mark, we recorded the total percent vegetation cover, dominant species and all species present to a water depth of 2 meters or 50 meters from shore. If a depth of 2 m was reached before 20 quadrats were measured, a second transect was performed 25 m to the right of the initial point. These observations were averaged to calculate percent total cover of vegetation in the littoral zone per lake (Marburg et al. 2005). The percent cover was transformed using arcsine square root of the decimal proportion.
Short Name
BIOMACR
Version Number
7

Biocomplexity at North Temperate Lakes LTER; Coordinated Field Studies: Color 2001 - 2004

Abstract
Chemical Limnology data collected for Biocomplexity Project; Landscape Context - Coordinated Field Studies Replicate chemical samples were pumped from the surface water (0.5m depth) and secchi depth was recorded at each lake. Temperature/dissolved oxygen profiles were taken throughout the water column at one meter intervals on all lakes. For more detail see the Water Sampling Protocol. Sampling Frequency: During 2001, temperature/dissolved oxygen profiles and secchi depths were taken twice during the stratified summer period. Chemistry samples were only taken once during the 2001 stratified period. From 2002 through 2004, all chemical and physical water samples were taken once during June (or resampled during the stratified period if June samples were bad). All lakes in which color, DIC/DOC, and chlorophyll samples were taken in 2001 were resampled in 2002 due to error in collection and/or analysis. Number of sites: 62 Vilas County lakes were sampled from 2001-2004 (approximately 15 different lakes each year).Allequash Lake, Anvil Lake, Arrowhead Lake, Bass Lake, Big Lake, Birch Lake, Ballard Lake, Big Muskellunge Lake, Black Oak Lake, Big Portage Lake, Brandy Lake, Big St Germain Lake, Camp Lake, Crab Lake, Circle Lily, Carpenter Lake, Day Lake, Eagle Lake, Erickson Lake, Escanaba Lake, Found Lake, Indian Lake, Jag Lake, Johnson Lake, Jute Lake, Katinka Lake, Lake Laura, Little Croooked Lake, Little Spider Lake, Little St Germain Lake, Little Crawling Stone Lake, Little John Lake, Lac Du Lune Lake, Little Rock Lake - North, Lost Lake, Little Rock Lake - South, Little Star Lake, Little Arbor Vitae Lake, Lynx Lake, Mccollough Lake, Moon Lake, Morton Lake, Muskellunge Lake, Nebish Lake, Nelson Lake, Otter Lake, Oxbow Lake, Palmer Lake, Pioneer Lake, Pallete Lake, Papoose Lake, Round Lake, Star Lake, Sparkling Lake, Spruce Lake, Stormy Lake, Twin Lake South, Tenderfoot Lake, Towanda Lake, Upper Buckatabon Lake, Vandercook Lake, White Sand Lake, Vilas County, WI, USA
Dataset ID
42
Date Range
-
Maintenance
completed
Metadata Provider
Methods
Environmental Sampling and Analysis: Physical, chemical and biological samples were taken above the deepest point in each lake during the summer stratification period (June, July, or August). Water samples were collected from one half meter depth using a peristaltic pump, and were analyzed for pH, alkalinity, specific conductance, water color, chlorophyll-a, dissolved organic and inorganic carbon, total phosphorus, and total nitrogen (Appendix Table 1). Secchi depth, temperature and dissolved oxygen profiles, and vertical plankton tows were also taken at the deepest point. Temperature and dissolved oxygen concentrations (DO) were measured through the water column at 1 meter increments.. Conductivity, TP-TN, alkalinity and pH water samples were collected unfiltered while water for DIC-DOC and color water samples was filtered through nucleopore polycarbonate filters. Alkalinity, pH, and DIC-DOC samples were filled to the top and sealed quickly to prevent CO2 loss or invasion. Samples containing air bubbles were recollected. Chlorophyll samples were collected on glass fiber filters in the field. Water chemistry and chlorophyll a analyses were done at the Trout Lake Biological Station, Boulder Junction, WI except for TP, TN, DIC and DOC samples, which were analyzed at the Center for Limnology-Lake Mendota Laboratory, Madison, WI.
Short Name
BIOCOLR1
Version Number
7

Biocomplexity at North Temperate Lakes LTER; Coordinated Field Studies: Chemical Limnology 2001 - 2004

Abstract
Chemical Limnology data collected for Biocomplexity Project; Landscape Context - Coordinated Field Studies Replicate chemical samples were pumped from the surface water (0.5m depth) and secchi depth was recorded at each lake. Temperature/dissolved oxygen profiles were taken throughout the water column at one meter intervals on all lakes. For more detail see the Water Sampling Protocol. Sampling Frequency: During 2001, temperature/dissolved oxygen profiles and secchi depths were taken twice during the stratified summer period. Chemistry samples were only taken once during the 2001 stratified period. From 2002 through 2004, all chemical and physical water samples were taken once during June (or resampled during the stratified period if June samples were bad). All lakes in which color, DIC/DOC, and chlorophyll samples were taken in 2001 were resampled in 2002 due to error in collection and/or analysis. Number of sites: 62 Vilas County lakes were sampled from 2001-2004 (approximately 15 different lakes each year).
Dataset ID
41
Date Range
-
Maintenance
completed
Metadata Provider
Methods
Environmental Sampling and Analysis: Physical, chemical and biological samples were taken above the deepest point in each lake during the summer stratification period (June, July, or August). Water samples were collected from one half meter depth using a peristaltic pump, and were analyzed for pH, alkalinity, specific conductance, water color, chlorophyll-a, dissolved organic and inorganic carbon, total phosphorus, and total nitrogen (Appendix Table 1). Secchi depth, temperature and dissolved oxygen profiles, and vertical plankton tows were also taken at the deepest point. Temperature and dissolved oxygen concentrations (DO) were measured through the water column at 1 meter increments.. Conductivity, TP-TN, alkalinity and pH water samples were collected unfiltered while water for DIC-DOC and color water samples was filtered through nucleopore polycarbonate filters. Alkalinity, pH, and DIC-DOC samples were filled to the top and sealed quickly to prevent CO2 loss or invasion. Samples containing air bubbles were recollected. Chlorophyll samples were collected on glass fiber filters in the field. Water chemistry and chlorophyll a analyses were done at the Trout Lake Biological Station, Boulder Junction, WI except for TP, TN, DIC and DOC samples, which were analyzed at the Center for Limnology-Lake Mendota Laboratory, Madison, WI.
NTL Keyword
Short Name
BIOCHEM1
Version Number
7

Biocomplexity at North Temperate Lakes LTER; Coordinated Field Studies: Lakes 2001 - 2004

Abstract
The study lakes selected for the "cross-lake comparison" segment of the Biocomplexity Project include 62 lakes located in Vilas County, Wisconsin. The lakes were chosen to represent a range of positions on gradients of both human development and landscape position.Allequash Lake, Anvil Lake, Arrowhead Lake, Bass Lake, Big Lake, Birch Lake, Ballard Lake, Big Muskellunge Lake, Black Oak Lake, Big Portage Lake, Brandy Lake, Big St Germain Lake, Camp Lake, Crab Lake, Circle Lily, Carpenter Lake, Day Lake, Eagle Lake, Erickson Lake, Escanaba Lake, Found Lake, Indian Lake, Jag Lake, Johnson Lake, Jute Lake, Katinka Lake, Lake Laura, Little Croooked Lake, Little Spider Lake, Little St Germain Lake, Little Crawling Stone Lake, Little John Lake, Lac Du Lune Lake, Little Rock Lake - North, Lost Lake, Little Rock Lake - South, Little Star Lake, Little Arbor Vitae Lake, Lynx Lake, Mccollough Lake, Moon Lake, Morton Lake, Muskellunge Lake, Nebish Lake, Nelson Lake, Otter Lake, Oxbow Lake, Palmer Lake, Pioneer Lake, Pallete Lake, Papoose Lake, Round Lake, Star Lake, Sparkling Lake, Spruce Lake, Stormy Lake, Twin Lake South, Tenderfoot Lake, Towanda Lake, Upper Buckatabon Lake, Vandercook Lake, White Sand Lake, Vilas County, WI, USA
Dataset ID
209
Date Range
-
Maintenance
completed
Metadata Provider
Methods
Study Lakes We selected 60 northern temperate lake sites in Vilas County, Wisconsin lake district. Methods for lake choice and sampling are given in greater detail in Marburg et al. (2005) Each lake was sampled once between 2001 and 2004, in June, July, or August (15 different lakes each summer). We chose stratified lakes deeper than 4 m to insure that all the lakes contained a diverse fish community. With two exceptions (chains of lakes), lakes were chosen to be in separate watersheds. Lakes were chosen based on two criteria landscape position, using historical DNR water conductivity data as a proxy of position, and riparian housing development, measured in buildings km-1 shoreline (Marburg et al. 2005). Landscape position refers to the location of a lake along the hydrological gradient. The gradient ranges from the top of a drainage system, where seepage lakes are fed mainly by rainwater, through lakes which receive water from groundwater and have surface outflows, to lakes further down in the drainage system, which receive water from both ground and surface flow (Kratz et al. 1997).Landscape position affects lake water chemistry, because as water flows across the surface and through soil, it picks up carbonates and other ions which increase the waters electrical conductivity (specific conductance, a temperature-independent measure of salinity), alkalinity, and its ability to support algal and macrophyte production. In addition, aspects of lake morphology correlate with landscape position. Most obviously, larger lakes tend to occur lower in drainage systems (Riera et al. 2000).The riparian (near-shore terrestrial) zone around northern Wisconsin lakes is being rapidly developed for use as both summer and permanent housing (Peterson et al., 2003). Concurrent with housing development, humans often directly and indirectly remove logs (Kratz et al. 2002) and aquatic vegetation (Radomski and Goeman 2001) from the littoral zone (near shore shallow water area), resulting in reduced littoral zone complexity. The slowly-decaying logs of fallen trees create physical structure (coarse woody habitat CWH) in the littoral zone of lakes that provides habitat and refuge for aquatic organisms (Christensen et al. 1996). Fish, including plankton-eating species (planktivores), reproduce and develop in shallow water (Becker 1983). Because planktivorous fish affect zooplankton community structure through size-selective predation (Brooks and Dodson 1965), there is the potential for indirect effects of housing development on zooplankton.Lakes ranged in size from 24 to 654 ha. In 2001, 2002 and 2004 we chose lakes from the extreme ends of the conductivity and housing density gradients and in 2003 lakes were chosen to fill in the gap in the middle of the ranges. The study lakes range from oligotrophic to mesotrophic (Kratz et al. 1997 Magnuson et al. 2005).At each lake we sampled zooplankton, water chemistry, riparian and littoral vegetation, fish, crayfish, and macrophytes. Each lake was sampled only once, but given the large number of lakes sampled in this area, we expect to see relationships between variables within lakes and at a landscape scale. A snapshot sampling design maximizes sites that can be visited, and is sufficient for a general characterization of zooplankton communities (Stemberger et al. greater than 001).
Short Name
BIOLAKE1
Version Number
5

Biocomplexity at North Temperate Lakes LTER; Coordinated Field Studies: Fish Individual 2001 - 2004

Abstract
Fish Data collected for Biocomplexity Project; Landscape Context - Coordinated Field Studies. The eight sportfishes of concern in this dataset; Bluegill, Pumpkinseed, Bluegill-Pumpkinseed hybrid, Largemouthbass, Smallmouthbass, Rockbass, Walleye, and Yellowperch, are the only species for which standard metrics (length (mm) and weight (g)) were taken. All other fish were identified to species and counted. Sampling Frequency: annually Number of sites: 58
Core Areas
Dataset ID
43
Date Range
-
LTER Keywords
Maintenance
completed
Metadata Provider
Methods
(revised 6or28or02)NOTE: This protocol is for each sample site. Eight sites are sampled on each lake.Day CrewEquipment checklist:25 (50 halves) Minnow Traps and Floats Measuring board25 (50 halves) Crayfish Traps and Floats GPS25 slices Beef Liver (6.5 packages) Balances (5, 10, 30g)25 slices of white bread (2 bags) Computer16 Reflectors 12 volt batteriesForceps Data sheetsScale Envelopes and paper (write in rain) Full fuel tankID keys PFDsForceps OarsSmall Tubs AeratorsMinnow nets Measuring tapePlace 1 slice of white bread in each minnow trap and 1 slice of beef liver in each crayfish traps. Minnow traps have 2.5cm diameter openings and crayfish traps have 7.6cm openings.Locate the beginning of each site using the GPS.Set three minnow traps and three crayfish traps in shallow water (approx. 1 m), spaced approximately 15m apart along the 50m riparian transect corresponding with plots A, C, and E. Set the crayfish and minnow traps within two meters of each other.Traps are fished for approximately 24 hours. Crayfish are identified to species, counted per trap, and returned to the lake. Fish caught in either the crayfish or minnow traps are identified to species. Bluegill, pumpkinseed, rock bass, largemouth bass, smallmouth bass, yellow perch, and walleye are measured for total length, weighed and scales taken if necessary (see processing fish below). Any other species caught are identified to species, counted for each trap, and returned to the lake.After pulling the traps at each site, set out the reflectors for electrofishing. The reflectors should be placed 25m before the start of the adjacent riparian transect and 25m after the end of the transect.Night CrewEquipment Checklist:Fishboards (large and small) ElectrofishBoxBalances (5, 10, 30, 60, 100, 500, 1000 grams) ForcepsComputer HeadlampsScale envelopes Cliplights (2)Batteries (2-12 volts) Running lightsFull fuel tanks (generator and boat) AeratorsPFDs GPSOars Dip nets (2)Big Tubs (3) Small tubsRubber boots and gloves (2 pairs) Spotlight (2)Locate each site by finding the reflectors with the spotlight.Electrofish eight 100m transects on each lake after sunset.Follow a 1.5m depth contour along the shoreline, but make sure to electrofish near littoral structure (docks, cwd, etc).Two dipnetters will net all fish regardless of size and place them in the livewell.The driver should record the average DC electrical output in amps and the time taken to complete each transect on the driver datasheet.times Note – Communication between the driver and the netters is essential. It is the netters responsibility to let the driver know about obstructions (logs, rocks, etc) in the water and to let them know if they have to back up for missed fish. Dont be shy, the driver has to hear you over the generator.PROCESSING FISHSort fish into small tubs by species if necessary.Measure the total length (from nose to end of caudal fins pinched together) in mm and weight in grams for these seven species:Bluegill PumpkinseedLargemouth Bass Smallmouth BassRock Bass Yellow PerchWalleyeTake several scales from 5 fish of each of these species (bluegill, largemouth bass, smallmouth bass, yellow perch, and walleye) from each 10mm size class. Keep track of the number of samples taken from each of these species using the scale tally sheet.For yoy fish (for yoy lengths see Table 1), take lengths and weights of 30 fish of each of the above seven species per lake. If possible take several of the 30 required fish from different locations, not all from the same site.Weights should be taken with the appropriate sized spring balance – the fish should be in the mid-range of the scale.Record the date, lake code, site number, fish ID number, species, length, and weight on the scale envelope.Take the scales from behind the left pectoral fin if looking at the fish from the dorsal side. Place at least 5 scales in the scale envelope.Take the third dorsal spine from 5 yellow perch and bluegill for each age class (Table 1). Place it in the scale envelope.Identify all other fish and keep a count for each species for each trap or electrofish run.If a fish cannot be positively identified, preserve it for later identification.Revive fish that have not recovered by holding them by their dorsal surface in the water and gently rocking them to the left and right to move water across the gills.times Note - Remember to hang pesola spring balances to dry after each sampling. If the springs rust they are not reliable. Spring balances are to be calibrated weekly.
Short Name
BIOFISH1
Version Number
6

Biocomplexity at North Temperate Lakes LTER; Coordinated Field Studies: Fish / Crayfish Abundance 2001 - 2004

Abstract
Abundance data for fish and crayfish collected for Biocomplexity Project; Landscape Context - Coordinated Field Studies http://infotrek.er.usgs.gov/doc/wdnr_biology/Public_Stocking/StateMapHotspotsAllYears.htm - Infomation on fish stocking by Wisconsin Department of Natural Resouces in Biocomplexity Lakes. Sampling Frequency: annually Number of sites: 58
Core Areas
Dataset ID
84
Date Range
-
Maintenance
completed
Metadata Provider
Methods
Littoral Zone Surveys: Littoral habitat, fish and macrophyte surveys were performed at eight sites within each of the 55 lakes. The sites were chosen by randomly selecting two points per compass quadrant of each lake. Each year littoral habitat surveys were conducted in June, fish surveys in July and macrophyte surveys in August.Littoral fish were sampled in July of each year, along the shallow areas (water depth greater than 0 and less than2 m) adjacent to the riparian plots. Night electroshocking and crayfish and minnow traps were used to catch fish and crayfish. All species were identified and counted.
Short Name
BIOFISH2
Version Number
8

Cross Lake Comparison at North Temperate Lakes LTER - Zooplankton Biomass Study 2006

Abstract
This project investigates why zooplankton size, but not biomass, has been found to influence the phosphorus (TP) - chlorophyll a (chl a) relationship (Pace 1984, Carpenter et al. 1991, Carpenter et al. 2001).
Dataset ID
220
Date Range
-
LTER Keywords
Maintenance
completed
Metadata Provider
Methods
Total phosphorus, chlorophyll a, and zooplankton samples were collected from 19 lakes in northeastern Wisconsin and Upper Michigan. Thirteen lakes are in Vilas County, WI (Star Lake, Anvil Lake, Stormy Lake, Camp Lake, Crab Lake, Little Crawling Stone Lake, Sparkling Lake, Lake Laura, Big Portage Lake, Crystal Lake, Tuesday Lake, Trout Lake, Lac du Lune, and Lynx Lake), one lake is in Oneida County, WI (Indian Lake) and 5 lakes lie within the University of Notre Dame Environmental Research Center (Peter Lake, Paul Lake, Tuesday Lake, Crampton Lake and Long Lake). The lakes were sampled in late May and June 2006. All sampled lakes lie within the coordinates 45 36 to 46 18 N and 89 00 to 89 54 W. Samples were collected from the deepest part of each lake. Lake information: Data collected on the sampledate include air temperature, an estimate of cloud cover, an estimate of wave height, maximum depth, secchi depth, and the depths of the epilimnion, metalimnion, and hypolimnion. Lakes identified as being located in UNDERC lie within the University of Notre Dame Environmental Research Center near Land O Lakes, Wisconsin, USA (89 32 W, 46 13 N). The location of the remaining lakes is identified by county - either Vilas or Oneida. Zooplankton Biomass: Five replicate zooplankton samples were collected from the deepest spot of each lake using vertical tows with a Wisconsin net (80 um mesh, 0.11 m radius). The tow was from 2 meters above the bottom of the lake to the surface. Zooplankton samples were preserved in 70percent ethanol. Each sample was drained through an 80 um mesh and sub-sampled three times using a 1 mL Hensen Stempel Pipette, and all zooplankton present in each subsample were identified down to genus or species. Thirty zooplankton of each genus or species in each 1 mL rep were measured using an ocular micrometer and a Leica MZ-8 dissecting microscope. To calculate biomass, the average weight for each species or genus per sample was applied to published dry weight- length regressions. Length-weight regressions (see methods) used to calculate biomass Zooplankton Lengths: Thirty zooplankton of each genus or species were measured using an ocular micrometer in a Leica MZ-8 dissecting microscope. All measurements are in mm. Note: Length measurements for Holopedium gibberum are of the post abdominal claw (between the setae natatores and the terminal claw). Total body length can be determined from the equation: Post abdominal claw length (um) equals 191.64 times Total Length (mm) plus 37.0 (Yan and Mackie 1986) Water Temperature/Dissolved Oxygen Profiles: A temperature and dissolved oxygen profile was taken on each lake on the sampling date Total Phosphorus and Total Nitrogen: Six samples were collected to determine the total phosphorus of each sampled lake. Triplicate 100-mL integrated samples were collected with a plastic tube (1.9 cm diameter) from the epilimnion. Discrete total phosphorus samples were collected with plastic tubing (0.6 cm) and a peristaltic pump from the middle of the metalimnion, the top of the hypolimnion and 1 meter above the bottom of the hypolimnion. Samples were preserved with 1 mL of Optima HCl and analyzed spectophotometrically for total phosphorus and total nitrogen. Some of the lakes were not completely stratified at the sampledate slightly altering the sampling method. In Crab Lake, Stormy Lake and Trout Lake the thermal profile made it difficult to determine the division between meta- and hypolimnion, so two additional samples were collected - from the metalimnion and from the top of the hypolimnion. In Anvil Lake, Big Portage Lake, Camp Lake, and Indian Lake, only one hypolimnion sample was collected because the lakes are shallow and were not completely stratified. Chlorophyll-a: Six integrated chlorophyll a samples (three epi- and three metalimnion) were collected from each lake using a plastic tube (1.9 cm diameter) and analyzed flourometrically. Sampling Frequency: Each of 19 lakes sampled once Number of sites: 19
Short Name
ZPBMASS
Version Number
22
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