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Jarl K. Hiltunen

Publications and source records attributed to Jarl K. Hiltunen.

18 recordsLinked to original sources
USGS2011

Rediscovery of lake balls in Lake Michigan

For the first time in 70 years, the occurrence of a 'lake ball' in Lake Michigan is here reported in the literature. According to a published system of classification, the object we collected in 1978 was a 'false' lake ball. Dissection revealed that it was colonized by 5 chironomid larvae and 162 oligochaetes. The species and numerical proportions of the oligochaetes indicated that it was formed in or near the mouth of a eutrophic tributary rather than in the open waters of Lake Michigan where it was found. Because of their mobility, false lake balls may be ecologically important, serving as natural vehicles for the dispersal of invertebrates.

Journal of Freshwater Ecology↗
USGS2003

Changes in the bottom fauna of western Lake Erie from 1930 to 1961

Samples were collected at 40 stations in western Lake Erie in 1961 to determine the species composition, distribution, and abundance of macrobenthonic organisms and to document changes since 1930, when a similar survey was made. The fauna in 1961 was composed principally of Oligochaeta, Tendipedidae (7 genera), Sphaeriidac (15 species), and Gastropoda (at least 8 species). Stations with a high density of Oligochaeta were near the principal sources of pollution (Maumee, Raisin, and Detroit rivers). Stations with fewer Oligochacta and a more diverse fauna were farthest from the river mouths. The population density of the burrowing mayfly, Hexagenia spp., was reduced from an average of 139/m 2 in 1930 to less than 1/m 2 in 1961. Organisms more abundant near the sources of pollution than in other areas were, in addition to Oligochaeta: the midge, Procladius; the fingernail clam, Sphaerium transversum; and the snail, Valvata sincera (sens. lat.). Organisms sensitive to pollution, such as amphipods, mayfly nymphs, caddisfly larvae, and naiad clams, were scarce and usually at the more lakeward stations. The most important changes in fauna during the 31-year period were: ninefold increase in Oligochacta; fourfold increase in Tendipedidae; twofold increase in Sphaeriidae; sixfold increase in Gastropoda; and a reduction of Hexagenia to less than 1% of former abundance. The area of pollution (as judged from the abundance of Oligochaeta) increased from 263 km 2 in 1930 to 1,020 km 2 in 1961.

Michigan, Ohio↗
USGS2003

Distribution of oligochaetes in western Lake Erie, 1961

A total of 52,390 oligochaetes were collected from 40 stations in western Lake Erie in spring 1961. The population was composed of two families, Naididae and Tubificidae. Only six species of naidids were found. One, Paranais frici, is apparently new to the list of North American freshwater Naididae. Among the 14 tubificids found, five species of Limnodrilus were most abundant; they contributed 90% or more of all oligochaetes at 33 of the 40 stations. Numbers of Limnodrilus were generally large near the mouths of the Detroit, Raisin, and Maumee rivers and decreased progressively lakeward. Stylodrilus heringianus, a pollution-intolerant species common in eastern Lake Erie, was not found in the western end of the lake.

Limnology and Oceanography↗
USGS1990

Anchistropus spp. (Crustacea: Cladocera: Chydoridae): a new distribution record for Lake Erie

This note extends the known Great Lakes distribution of Anchistropus sp. from Lake Michigan, Huron, Superior, and St. Clair to Rondeau Harbor in Lake Erie. Anchistropus sp. was collected in benthic samples where it occurred as epibionts on hydra. Previous studies, which are briefly reviewed, have noted the parasitic nature of Anchistropus . Although only one species of Anchistropus ( A. minor ) is known from North America, our specimens cannot be positively identified as that species: the structure of the postabdomen and first leg differs from the original taxonomic description of A. minor . Others have noted differences between the original description of A. minor and the morphology of specimens collected over the succeeding years.

Journal of Great Lakes Research↗
USGS1990

Redefinition of Teneridrilus Holmquist (Oligochaeta: Tubificidae), with description of two new species from North America

The tubificid genus Teneridrilus Holmquist, 1985 (subfamily Tubificinae) is redefined. The genus was originally monotypic for the type species, formerly classified as Ilyodrilus mastix Brinkhurst, 1978. The genus now includes Teneridrilus columbiensis, a new combination for Isochaetides columbiensis, and two new species. The first of these, Teneridrilus calvus, is described by Erseus and Brinkhurst, and the second, Teneridrilus flexus, by Erseus and Hiltunen. Synapomorphies for the genus are strongly modified chaetae in II and an enlarged eversible pharnyx. The genus is distributed from China to British Columbia, Washington and California in freshwater near the mouths of large rivers, and in the St. Marys River, which connects Lake Superior with Lakes Michgan and Huron.

Proceedings of the Biological Society of Washingto↗
USGS1985

Varechaetadrilus fulleri (Oligochaeta: Tubificidae): New record and amendment of morphological description

The tubificid worm Variechaetadrilus fulleri (Annelida: Oligochaeta) was described by Brinkhurst and Kathman (1983) from the Green River, Kentucky, the only locality from which the species has previously been reported. In 1982-84, a number of specimens of V. fulleri were found in the lower Mississippi River and in an adjacent oxbow lake (Eagle Lake), about 19 river kilometers northwest of Vicksburg, Mississippi. In the lake, the species was collected in the inshore 1-m depth zone but not at 1.6-m depths offshore, where the waters stratified thermally in July and August and the dissolved oxygen concentration sometimes fell to 0.5 mg/liter in the hypolimnion. The collection of sexually mature worms in the river in May 1982 and in Eagle Lake in January-February 1984 enabled us to describe anatomical details that refine the description of the species.

Freshwater Invertebrate Biology↗
USGS1984

Life cycle of a mayfly Hexagenia limbata in the St. Marys River between Lakes Superior and Huron

Length-frequency distribution curves of Hexagenia limbata nymphs collected in May, August, and October 1974 and May 1975 in the St. Marys River between Lakes Superior and Huron were bimodal for each sampling period. These curves, combined with interpretation of nymphal emergence period and mean surface water temperatures, indicate that the population of Hexagenia nymphs in the St. Marys River is composed of two year classes or cohorts. One cohort emerges per season, 2 years after egg deposition.

Journal of Great Lakes Research↗
USGS1983

The occurrence of oil and the distribution of Hexagenia (Ephemeroptera: Ephemeridae) nymphs in the St. Marys River, Michigan and Ontario

We sampled benthos from the St. Marys River in May 1974 and May 1975 to determine visibly the occurrence of sorpted oil and the distribution of nymphs of the burrowing mayfly Hexagenia in the bottom of the Lake George and Lake Nicolet channels. Results of our survey showed that, between 1967 and 1974-75, the occurrence of oil in the substrate of the Lake George Channel had advanced from 16 km to 30 km downstream from the point where oil is discharged at Sault Ste. Marie, Ontario. Absence or low densities of nymphs coincided with the presence of oil in the sediments. In the Lake Nicolet Channel, evidence of oil pollution was meager and the density of Hexagenia nymphs was generally high.

Freshwater Invertebrate Biology↗
USGS1975

Book Review: The benthos of lakes

No abstract available. Review info: The benthos of lakes. By Ralph O. Brinkhurst, 1974. ISBN: 978-1930665705, 190 pp.

Journal of the Fisheries Research Board of Canada↗
USGS1971

Limnological data from Lake St. Clair, 1963 and 1965

Data, primarily benthological, are given for collections made at 14 stations. Included are records of water transparency, water temperature, water samples for chemical analysis, and bottom samples for the analysis of the macrobenthos.

Data Report↗
USGS1969

Invertebrate macrobenthos of western Lake Superior

The present report contributes to knowledge of the relative abundance of major groups of benthic invertebrates in western Lake Superior, primarily in the Apostle Islands region. Observations are made on the depth habitation of certain species, and some of the fauna are compared to that in some of the other Great Lakes. Also included is a note on the catch of benthic organisms in a plankton-net tow, and a note on Oligochaeta from Chequamegon Bay and the harbors of Duluth and Superior.

Michigan Academician↗
USGS1969

The benthic macrofauna of Lake Ontario

The presence and relative abundance of bottom macrofauna in Lake Ontario are documented. Bottom samples were collected at 24 stations in September 1964. The quantity of organisms and the distribution of some species were affected by depth of water. Samples from the shallower stations (47.5 m or less) yielded an average of 41,631 organisms per mA? whereas the deeper stations (91.5 m or more) yielded an average of only 7,938. The Oligochaeta, the most abundant group of macroinvertebrates, was represented by four families - Enchytraeidae, Lumbriculidae, Naididae, and Tubificidae. The lumbriculid worm, Stylodrilus heringianus, and the burrowing amphipod, Pontoporeia affinis, were rare or absent in areas affected by pollution. In kinds and abundance of organisms, the bottom fauna in Lake Ontario was generally similar to that in Lake Michigan.

Technical Report↗
USGS1968

Distribution and abundance of the Japanese snail, Viviparus japonicus, and associated macrobenthos in Sandusky Bay, Ohio

A survey of the macrobenthos of Sandusky Bay, Lake Erie, in June, 1963, provided information on the abundance and distribution of the introduced Japanese snail, Viviparus japonicus, which has become a nuisance to commercial seine fishermen. The abundance and distribution varied considerably within the bay; at the time of the survey, most snails were found near the north-central shore. Environmental characteristics were nearly uniform and had no apparent effect on the distribution; concentrations in different areas at different times appeared to result from water movements induced by winds. The time of the study coincided with a period of reproduction; young-of-the-year snails were most abundant in areas where adults were most common. The frequency distributions of shell height and diameter suggested the presence of two age groups of adults in the population. Considerable natural mortality was seen, both at the time of the study and in other seasons. Only three other gastropods were observed in the bay; the most abundant was another viviparid, Campeloma decisum. Other mollusks present were four species of Sphaeriidae and 18 species of Unionidae. A summary of invertebrates found, other than the mollusks, is also presented.

Ohio Journal of Science↗
USGS1967

Some oligochaetes from Lake Michigan

Twenty-six species of Tubificidae, 12 Naididae, and 1 Lumbriculidae were found in three regions of Lake Michigan- Green Bay, the southern end of the lake proper, and the harbor at Ludington, Michigan. One new naidid species is described. Methods of identification of some species are discussed and illustrated. The abundance of oligochaetes and distribution of certain species vary with depth and location. Data are presented on the effects of the environment on the distribution of certain species. The presence or absence of some species reflected the quality of the environment; some were prevalent in polluted waters whereas others were restricted or absent. Possible changes in composition and abundance of species are outlined if organic enrichment increases in Lake Michigan.

Illinois, Indiana, Michigan, Wisconsin↗