• 2010 Status of the Lake Ontario Lower Trophic Levels

      Holeck, Kristen T.; Hotaling, Christopher; Swan, Jonathan W.; Rudstam, Lars G.; McCullough, Russ; Lemmon, Dave; Pearsall, Web; Lantry, Jana R.; Connerton, Mike; LaPan, Steve; et al. (2010-01-01)
      This report presents data on the status of lower trophic level components of the Lake Ontario ecosystem (zooplankton, phytoplankton, nutrients) in 2010 and compares the 2010 data with available time series. Lower trophic levels are indicators of ecosystem health [as identified by the Lake Ontario Pelagic Community Health Indicator Committee (EPA 1993) and presented in the biennial State of the Lake Ecosystem Conference (SOLEC) reports] and determine the lake’s ability to support the prey fish upon which both wild and stocked salmonids depend. Understanding the production potential of lower trophic levels is also integral to ecosystem-based management. Continued evaluation of lower trophic levels is particularly important for fisheries management, as the observed declines in alewife and Chinook salmon in Lake Huron in 2003 may have been partly the result of changes in lower trophic levels (Barbiero et al. 2009).
    • Changes in zooplankton community, and seston and zooplankton fatty acid profiles at the freshwater/saltwater interface of the Chowan River, North Carolina

      Lichti, Deborah A.; Rinchard, Jacques; Kimmel, David G.; Lichti, Deborah; Rinchard, Jacques; Kimmel, David G.; East Carolina University; The College at Brockport (2017-08-16)
      The variability in zooplankton fatty acid composition may be an indicator of larval fish habitat quality as fatty acids are linked to fish larval growth and survival. We sampled an anadromous fish nursery, the Chowan River, during spring of 2013 in order to determine how the seston fatty acid composition varied in comparison with the zooplankton community composition and fatty acid composition during the period of anadromous larval fish residency. The seston fatty acid profiles showed no distinct pattern in relation to sampling time or location. The mesozooplankton community composition varied spatially and the fatty acid profiles were typical of freshwater species in April. The Chowan River experienced a saltwater intrusion event during May, which resulted in brackish water species dominating the zooplankton community and the fatty acid profile showed an increase in polyunsaturated fatty acids (PUFA), in particular eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). The saltwater intrusion event was followed by an influx of freshwater due to high precipitation levels in June. The zooplankton community composition once again became dominated by freshwater species and the fatty acid profiles shifted to reflect this change; however, EPA levels remained high, particularly in the lower river. We found correlations between the seston, microzooplankton and mesozooplankton fatty acid compositions. Salinity was the main factor correlated to the observed pattern in species composition, and fatty acid changes in the mesozooplankton. These data suggest that anadromous fish nursery habitat likely experiences considerable spatial variability in fatty acid profiles of zooplankton prey and that are correlated to seston community composition and hydrodynamic changes. Our results also suggest that sufficient prey density as well as a diverse fatty acid composition is present in the Chowan River to support larval fish production.
    • Changes in zooplankton community, and seston andzooplankton fatty acid profiles at the freshwater/saltwater interface of the Chowan River, North Carolina

      Lichti, Deborah; Rinchard, Jacques; Kimmel, David G.; East Carolina University; NOAA Fisheries, Alaska Fisheries Science Center; The College at Brockport (2017-08-16)
      The variability in zooplankton fatty acid composition may be an indicator of larval fish habitat quality as fatty acids are linked to fish larval growth and survival. We sampled an anadromous fish nursery, the Chowan River, during spring of 2013 in order to determine how the seston fatty acid composition varied in comparison with thezooplanktoncommunitycompositionandfattyacidcompositionduringtheperiod of anadromous larval fish residency. The seston fatty acid profiles showed no distinct pattern in relation to sampling time or location. The mesozooplankton community composition varied spatially and the fatty acid profiles were typical of freshwater species in April. The Chowan River experienced a saltwater intrusion event during May,whichresultedinbrackishwaterspeciesdominatingthezooplanktoncommunity andthefattyacidprofileshowedanincreaseinpolyunsaturatedfattyacids(PUFA),in particulareicosapentaenoicacid(EPA)anddocosahexaenoicacid(DHA).Thesaltwater intrusioneventwasfollowedbyaninfluxoffreshwaterduetohighprecipitationlevels in June. The zooplankton community composition once again became dominated by freshwaterspeciesandthefattyacidprofilesshiftedtoreflectthischange;however,EPA levels remained high, particularly in the lower river. We found correlations between the seston, microzooplankton and mesozooplankton fatty acid compositions. Salinity was the main factor correlated to the observed pattern in species composition, and fatty acid changes in the mesozooplankton. These data suggest that anadromous fish nursery habitat likely experiences considerable spatial variability in fatty acid profiles of zooplankton prey and that are correlated to seston community composition and hydrodynamic changes. Our results also suggest that sufficient prey density as well as a diverse fatty acid composition is present in the Chowan River to support larval fish production.
    • Leptodora Kindtii (Focke): Seasonal Population Abundance and Food Web Interactions in Lake Ontario; 1984, 1986, and 1987

      Makarewicz, Joseph C.; Koapaha, Joutje Ariel; The College at Brockport (1989-01-01)
      In 1984, 1986, and 1987 five stations in Lake Ontario off Sandy Creek were sampled biweekly to determine the abundance and biomass of the zooplankton Leptodora kindtii (Focke) and its links in the food web. The seasonal abundance and distribution of Leptodora kindtii in Lake Ontario were governed by temperature and productivity of habitat. The minimum temperature which Leptodora kindtii occurred in Lake Ontario was 6.0o C. The highest abundance occurred proportionally with the highest temperatures in the months of late July and August. The population is mostly comprised of the female Leptodora during this period. The first appearance of male Leptodora in Lake Ontario occurred in mid-August and their numbers gradually increased with time. Leptodora kindtii is a multivoltine organism which does not have a clearly separable cohort. Average abundance of Leptodora at the nearshore station ranged from 26.5 Leptodora/m3 in 1984, 2.8 and31.7 Leptodora/m3 (inside and outside the Brockport Water Intake Plant, respectively) in 1986, and zero in 1987. The average abundance for the offshore station ranged from 9.8 Leptodora/m3 in 1984 to 28.7 Leptodora/m3 in 1987. There was a positive correlation between alewife abundance and Leptodora abundance over several years of varying forage fish abundance. This suggests that alewife do not affect Leptodora abundance in Lake Ontario, which is contrary to the results of previous studies in other lakes.
    • NYSDEC Lake Ontario Annual Report 2010

      2010-01-01
      Maps and charts from 1981 - 2010 biomonitoring sites, as compiled by the New York State Department of Environmental Conservation.
    • Phytoplankton and Zooplankton Composition, Abundance and Distribution and Trophic Interactions: Offshore Region of Lakes Erie, Lake Huron and Lake Michigan, 1985

      Makarewicz, Joseph C.; Lewis, Theodore W.; Bertram, Paul; The College at Brockport; U.S. Environmental Protection Agency (1989-08-01)
      During the spring, summer and autumn of 1985, the structure of the phytoplankton and zooplankton communities in the offshore waters of Lake Michigan, Lake Huron and Lake Erie was monitored. In Lake Michigan, the presence of an oligotrophic rotifer association and the oligotrophic crustacean indicator species Diaptomus sicilis and Limnaealanus macrurus, the predominance of mesotrophic diatom species, and the abundance and biomass of plankton between that of Lake Huron and Lake Erie suggest that the offshore waters are currently in the oligotrophic-mesotrophic range. In Lake Huron, the presence of an oligotrophic rotifer assemblage, the domination of the calanoid copepods, the abundance of the oligotrophic Diaptomus sicilis, and relatively low zooplankton abundance suggest that the offshore waters continue to be oligotrophic. In Lake Erie, phytoplankton and zooplankton species composition and biomass suggest a more productive status than Lake Michigan and Lake Huron. Data support the classification of the Western Basin as meso-eutrophic, the Central Basin as mesotrophic and the Eastern Basin as oligo-mesotrophic. Significant changes in the composition of the zooplankton community with the appearance of the large cladoceran Daphnia pulicaria in Lake Erie are attributed to a change in planktivory. The planktivorous emerald and spottail shiners have dramatically declined in abundance, possibly due to a resurgence of the walleye and the salmonine stocking programs.
    • Phytoplankton and Zooplankton Composition, Abundance and Distribution: Lake Erie, Lake Huron and Lake Michigan-1983

      Makarewicz, Joseph C. (1987-04-01)
      An in-depth comparison of phytoplankton and zooplankton from Lakes Erie, Huron and Michigan is presented based on extensive lake-wide surveys during spring, summer and autumn of 1983. This comparison was achieved by the application of standard and consistent identification, enumeration and data-processing techniques of plankton along north-south transects in Lakes Huron and Michigan and east-west transects in Lake Erie. For lakes Erie, Huron and Michigan respectively, 436, 411 and 452 algal taxa and 71, 61 and 73 zooplankton taxa were identified. Based on indicator species and species associations, the plankton assemblage was consistent with a mesotrophic-eutrophic designation for Lake Erie, oligotrophic destination for Lake Huron, and mesotrophic-oligotrophic designation for Lake Michigan. Species lists for each are provided. Original source data for each station visit are provided in the attached microfiche.
    • Phytoplankton and Zooplankton: In Lakes Erie, Lake Huron and Lake Michigan: 1984

      Makarewicz, Joseph C.; The College at Brockport (1987-03-01)
      With the acknowledgement that biological monitoring was fundamental to charting ecosystem health (Great Lakes Water Quality Agreement 1978), EPA's program was developed for Lakes Erie, Huron and Michigan to: 1) monitor seasonal patterns, ranges of abundance and, in general, structure of the phytoplankton and zooplankton communities; 2) relate the biological components to variations in the physical, nutrient and biological environment; and 3) assess the annual variance to allow better long-term assessments of trophic structure and state. Several offshore stations (9-11) on several cruises (9-11) during the spring, summer and autumn of 1984 and winter of 1985 were sampled. By examining changes in the phytoplankton and zooplankton in relation to water chemistry, evidence was found suggesting little change in the trophic status of Lakes Huron and Michigan while an improvement in the trophic status of Lake Erie was evident. The offshore region of Lake Michigan is experiencing changes in phytoplankton and zooplankton composition consistent with nutrient control and top-down control by fish. Even so, the biomass of phytoplankton and zooplankton and the trophic status of the lake have not changed significantly. The appearance and establishment of Daphnia pulicaria in offshore waters of Lake Huron suggest a change in the forage fish base. With the exception of the resurgence of Asterionella formosa in Lake Erie, plankton composition has changed little since the 60's. However, dramatic reductions in biomass of nuisance and eutrophic indicator species have occurred. These changes are consistent with expectations of long-term nutrient control. However, a change in piscivory is evident that has apparently allowed the establishment of the large cladoceran Daphnia pulicaria.
    • Phytoplankton, Zooplankton, Macrobenthos and lchthyoplankton Abundance, Biomass and Species Composition in Onondaga Lake, 1994

      Makarewicz, Joseph C.; Cady, Bruce L.; Lewis, Theodore W.; Buttner, Joseph K.; Haynes, James M.; The College at Brockport (1995-02-01)
      Once a pristine recreational center and a productive fishery that supplied New York City markets with fresh fish, Onondaga Lake is now considered one of the most badly degraded bodies of water in the entire world (Sage 1993). The Onondaga Lake Management Conference was established to develop a comprehensive restoration, conservation, and management plan for Onondaga Lake that recommends priority corrective actions and a compliance schedule for cleanup of the lake. Biological assessment of the lake has been infrequent and concentrated on a few biological groups. This study either updates or establishes baseline characteristics for the following biological components of the Onondaga Lake ecosystem: phytoplankton, zooplankton, ichthyoplankton and macrobenthos.
    • Predatory Impact of Exotic Cladoceran Cercopagis pengoi on the Zooplankton of Lake Ontario

      Laxson, Corey L.; The College at Brockport (2002-08-01)
      Despite growing knowledge of the ecology of Cercopagis in North America, little information exists on its effects on the composition and abundance of zooplankton and phytoplankton. I assessed the impact of Cercopagis on the lower food-web of Lake Ontario by analyzing the historical and seasonal abundance of the crustacean zooplankton, by conducting laboratory feeding experiments, and by estimating consumption demand of Cercopagis based on bioenergetic considerations. A comparison of average pre-and post-invasion abundances of Daphnia retrocurva, Bosmina longirostris and Diacyclops thomasi suggests that Cercopagis is having a major effect on zooplankton abundance in the lake. In the laboratory Cercopagis fed on a number of zooplankton including the rotifer Asplanchna priodonta and the cladocerans, Daphnia retrocurva, Bosmina longirostris, Ceriodaphnia lacustris, Scapheloberis kingi, and Leptodora kindtii. Between 1999 and 2001 decreases in the abundance of common members of the zooplankton community coincided with an increase in the abundance of Cercopagis. Daphnia retrocurva populations declined despite high birth rates in all three years, indicating that food limitation was not responsible for the patterns. Chlorophyll-a concentration generally increased concomitant with declines in cladoceran zooplankton abundance. Consumption demand of average mid-summer populations of Cercopagis, estimated from the bioenergetic model of confamilial Bythotrephes, were sufficient to decimate much of the crustacean community in a few days. Predatory effects exerted by Cercopagis on the Lake Ontario zooplankton community have decreased steadily since the species was established in the lake.
    • Structure and Function of the Zooplankton Community of Mirror Lake, New Hampshire

      Makarewicz, Joseph C.; Likens, Gene E.; Cornell University; The College at Brockport (1979-03-01)
      An intensive study of the zooplankton community of Mirror Lake, New Hampshire, was undertaken over a 3-yr period. Our objectives in the lake study have included measurements of a number of attributes of the zooplankton community that integrate structure and function at the ecosystem level; among these are dispersion, biomass, productivity, respiration, and nutrient cycling. Eight species of rotifers and 3 species of cladocerans were successfully cultured. Generation time for planktonic rotifers was -8-10 days (170C). The effect of higher food levels on rotifers was to shorten generation time and to increase brood size. In cladocerans, high food levels caused an increase in length and brood size . A curvilinear relationship existed between zooplankton community respiration and temperature in Mirror Lake. Mean monthly zooplankton community respiration ranged from 96.0 kg C/ha/mo in June of 1969 to a low of 20.5 kg C/ha/mo in April of 1970. Over a 3-yr period, respiration was 79.9% of assimilation. The 0 to 4.5-m strata (;epilimnion) contributed 68.5% and 46.5% of the annual zooplankton production and biomass. Zooplankton community production ranged from 22.3 kg C/ha/yr to 29.3 kg C/ha/yr with a 3-yr mean of 25.2 kg C/ha/yr. The annual zooplankton biomass ranged from 1.4 to 2.6 kg C/ha with a 3-yr mean of 2.0 kg C/ha. A linear relationship was found to exist between net phytoplankton and zooplankton production in various lakes of the world. Ecological efficiency apparently increases with the trophic status of the lake. It is recommended that the term ecological efficiency be refined to include both autochthonous and allochthonous inputs of reduced carbon into the lake. Rotifers assume a major role in intrasystem nutrient cycling and energy transfer within the lake ecosystem. Of the total amount of P incorporated into the organic matter of zooplankton community each year, 33.5% is assimilated in rotifer tissue. The annual turnover rate of P by rotifers is 30.9 and is high compared to crustaceans (10.1). Copepods comprise 55.4% of the total zooplankton biomass. However, the copepods, with their slow growth over an entire year, represent only 19.3% of the zooplankton production, while rotifers account for 39.8% of the zooplankton production annually in Mirror Lake. Also, evidence is presented that rotifers play a major role in energy transfer in lakes of varying trophic status (oligotrophic to eutrophic).
    • The Ecology of the Zooplankton Community of a Small Quarry Pond with Special Reference to the Rotifers

      Costa, Robert R.; Curro, Leo J.; The College at Brockport (1972-01-01)
      This study examines the effect of ecological factors within a small limestone quarry pond environment on the relevant biota. The author collected plankton samples over a period of six months in order to track the vertical distribution patterns within various species of zooplankton, while gathering quantitative data on seasonal physical/chemical changes of the pond. Specimens were collected using a net towed for a distance of 18-27m at depths of 0m, 0.5m, and 1.5 m. On completion, the net was removed from the water and organisms were concentrated into a 30ml vial. The sample was then poured into a different bottle and combined with 20ml of filtered pond water. Samples were transported immediately to the laboratory where all rotifers were live-counted using an A O Spencer binocular microscope. After completing the live count, the researcher preserved the sample and performed a second count using Congo Red stain at a later date. Crustaceans were immediately preserved and counted at a later date. The researcher observed a positive relationship between water temperature and the abundance of zooplankton, and a negative relationship between dissolved oxygen concentrations and planktonic organisms. Crustaceans did not seem to be affected by low concentrations of dissolved O_2. The researcher observed that pond depth affected the composition of the zooplankton populations. The researcher concludes that a combination of abiotic and biotic factors appear to play an important role in influencing and regulating zooplankton populations, lessening competition in the relatively shallow quarry pond.
    • The invasive species Cercopagis pengoi in Lake Ontario I. Position in the food web II. Impact on mirex concentrations in the biota III. Temporal changes in mirex concentrations in salmon

      Makarewicz, Joseph C.; Damaske, Elizabeth T.; The College at Brockport (2002-02-01)
      This study investigates the position of invasive zooplankton species Cercopagis pengoi in the Lake Ontario food web as well as its impact on mirex concentrations in the biota. Seasonal Cercopagis samples were collected weekly from May through November 2000 for abundance measurements. Seasonal zooplankton samples were also collected weekly from May through September 2001 for abundance measurements using a Wisconsin net (63 µm mesh size, 50-cm diameter). Each catch was washed into buckets, transferred to bottles, and preserved with 10% buffered formalin. In the lab, zooplankton were identified and enumerated to the species level following methods of Gannon. Zooplankters were subsampled and measured from the anterior margin of the helmet to either the base of the tail spine or caudal setae. Zooplankton samples were also collected during the summers of 2000 and 2001 for pesticide analysis. Samples were visually inspected for relative composition, then placed in solvent rinsed glass jars, kept in ice and transported back to the lab, where they were frozen until analysis. Salmonids were collected during their spawning run in the fall of 1999 via electroshocking and gill netting. Alewives were collected monthly from May to November 2000 by gill netting. Fish length, weight, sex, and age were determined by standard procedures. Salmonines subsamples were prepared for chemical analysis by taking a fillet from the fish and homogenizing it before freezing it in solvent rinsed glass jars. Whole alewives were gutted and homogenized. The stomachs of salmonine and alewife sub-samples were removed and their diet was analyzed. Mirex and photomirex were quantified by electron capture (63­Ni) gas chromatography. All samples were analyzed for stable isotopes of carbon and nitrogen. Results indicate that the invasion of Cercopagis pengoi into Lake Ontario does not represent an “extra step” of significance in the pelagic food web, but it is a link. While nutrients flow from Cercopagis to alewives, it only represents a small portion of the alewife diet. As a result, no increases were observed in the monthly mirex concentrations in alewives.