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At least 487 records · Page 27Linked to original sources
USGS1991

Evidence for color phase effects on the breeding and life history of Northern Fulmars

About 15% of Northern Fulmars ( Fulmarus glacialis ) breeding on the Semidi Islands in 1979 had light-phase plumage; the remainder were dark. Fulmars of different plumage types mated indiscriminantly, but the lighter member of a mixed pair was more likely to be male than female. Pairs that included at least one light-phase member had lower breeding success than dark/dark pairs in one of six years. Constancy of breeding site use differed between light/dark and dark/dark pairs, suggesting dark birds skipped more breeding attempts or had lower over-winter survival than light birds. The apparent effect of breeding experience (assessed by site fidelity) on success also differed between pair types. The polymorphism on the Semidi Islands may result from light-phase fulmars immigrating from the Bering Sea, but there is also evidence to suggest it is maintained by balancing selection in a closed population.

Alaska↗
USGS2002

Life history and propagation of the endangered fanshell pearlymussel, Cyprogenia stegaria Rafinesque (Bivalvia: Unionidae)

Aspects of the reproduction, age, growth, fish hosts, and culture of juveniles were determined for the endangered fanshell pearlymussel, Cyprogenia stegaria Rafinesque, 1820, in the Clinch River, Tennessee. Glochidia of C. stegaria are contained in red, worm-like conglutinates that resemble oligochaetes. Conglutinates are 20 to 80 mm long and are released through the excurrent aperture. Estimated fecundity was 22,357 to 63,459 glochidia/mussel. Eighty-four valves of C. stegaria were thin-sectioned for aging; ages ranged from 6 to 26 y. Of 16 fish species tested, 9 hosts were identified through induced infestations of glochidia: mottled sculpin (Cottus bairdi), banded sculpin (Cottus carolinae), greenside darter (Etheostoma blennioides), snubnose darter (Etheostoma simoterum), banded darter (Etheostoma zonale), tangerine darter (Percina aurantiaca), blotchside logperch (Percina burtoni), logperch (Percina caprodes), and Roanoke darter (Percina roanoka). Newly metamorphosed juveniles were cultured in recirculating and nonrecirculating aquaculture systems within dishes containing sediments of 300 to 500 μm diameter (sand) or <105 μm diameter (silt), and fed either the green algae Neochloris oleoabundans or Scenedesmus quadricauda daily. Growth and survival of juvenile mussels were highest in the nonrecirculating aquaculture system, with a mean survival of 72% after 2 wk and 38% after 4 wk.

Journal of the North American Benthological Societ↗
USGS2001

Life in the fast lane: Fish and foodweb structure in the main channel of large rivers

We studied the main channel of the lower Illinois River and of the Mississippi River just upstream and downstream of its confluence with the Illinois River to describe the abundance, composition, and/or seasonal appearance of components of the main-channel community. Abundance of fishes in the main channel was high, especially adults. Most adult fishes were present in the main channel for either 3 or 4 seasons/y, indicating that fishes regularly reside in the main channel. We documented abundant zooplankton and benthic invertebrates in the main channel, and the presence of these food types in the diets of channel catfish and freshwater drum. All trophic levels were well represented in the main channel, indicating that the main channel supports a unique food web. The main channel also serves as an important energetic link with other riverine habitats (e.g., floodplains, secondary channels, backwater lakes) because of the mobility of resident fishes and because of the varied energy sources supplying this food web. It may be more realistic to view energy flow in large-river systems as a combination of 3 existing concepts, the river continuum concept (downstream transport), the flood pulse concept (lateral transport to the floodplain), and the riverine productivity model (autochthonous production). We urge additional research to quantify the links between the main channel and other habitat types in large rivers because of the apparent importance of main-channel processes in the overall structure and function of large-river ecosystems.

Illinois↗
USGS1959

The life-cycle of the digenetic trematode, Proctoeces maculatus (Looss, 1901) Odhner, 1911 (Syn. P. rubtenuis [Linton, 1907] Hanson, 1950), and description of Cerceria adranocerca n. sp

The genus Proctoeces was erected by Odhner ( 191 1) to contain Distonium maculatuni Looss, 1901, from Labrus merula and Crenilabrus spp . at Triest. Odhner had found the parasite in Blennius ocellaris at Naples. One adult specimen from Chrysophrys bifasciata and two immature specimens from lulis lunaris taken in the Red Sea, were described as a new species, Proctoeces erythraeus . Dawes (1946) listed P. erythraeus as a synonym of P. maculatus (Looss) , but the species was recognized by Manter ( 1947) on the basis of six specimens he had collected from Calamus calamus and Calamus bajonado at the biological laboratory of the Carnegie Institution at Dry Tortugas, Florida. Several additional species have been de scribed. Fujita ( 1925) reported a metacercaria from the Japanese oyster, Ostrea gigas , as a new species, Proctoeces ostreae . The paper was translated by R. Ph. Dollfus who noted (p. 57) ,&ldquo;Il est &agrave; souhaiter que des recherches chez les poissons mangers de Lamellibranches, sur les c&ocirc;tes de la pr&eacute;fecture d'Hiroshima, permettent de d&eacute;couvrir des exemplaires compl&egrave;tement adultes de Proctoeces ostreae Fuj., chez lesquels l'extension des vitellog&egrave;nes et les dimensions des oeufs puissent &ecirc;tre observ&eacute;es avec pr&eacute;cision; il sera alors possible de savoir d&eacute;finitivement si P. ostreae Fuj. doit ou non tomber en synonymie avec P. maculatus (Looss)." Yamaguti (1934) described P. maculatus from Sparus aries , Sparws macrocephalus, Pagrosomus auratus , and Epinephelus akaara in Japan. Several specimens from Pagrosomus auratus , which differed from P. maculatus in larger size, larger eggs, and trilobed ovary, he described as a new species, Proctoeces major . Yamaguti ( 1938) reported P. nzaculatus from Sensicossyphus reticulatus and described a larva from the liver of the pelecypod mollusk, Brachidontes senhausi , as an unidentified member of the genus Proctoeces. Manter ( 1940) described Proctoeces tnagnorus from a single specimen found in the intestine of Caulolatilus ano ,nalus, taken at Cerros Island, Mexico. Hanson ( 1950) identified two specimens collected from Calamus sp . at Bermuda by the late F. D. Barker as Distontuni subtenue Linton, 1907, a species described originally from Calantus calanius in the same area. Comparison of these specimens with those from Tortugas identified by Manter as P. erythraeus established their identity, and P. erythraeus was suppressed as a synonym of Proctoeces subtenue (Linton, 1907). Hanson corrected the statement of Manter (1947), noting that it is the vitellaria, not the uterus, which never extends into the post testicular region.

Biological Bulletin↗
USGS1963

Some phases of the life history of the trout-perch

The trout-perch, Percopsis omiscomaycus (Walbaum), is one of the more abundant forage fishes in the larger lakes of midwestern United States and central Canada where walleye, Stizostedion v. vitreum (Mitchill), yellow perch, Perca flavescens (Mitchill), and coregonids predominate. It has been suggested that it may have considerable effect on perch and walleye populations of these lakes. The present study describes growth, food habits, population structure, year-class strengths, and reproductive capacity of the trout-perch in relation to its population dynamics in lower Red Lake, Minnesota.

Ecology↗
USGS2010

Multi-stage origin of the Coast Range ophiolite, California: Implications for the life cycle of supra-subduction zone ophiolites

The Coast Range ophiolite of California is one of the most extensive ophiolite terranes in North America, extending over 700 km from the northernmost Sacramento Valley to the southern Transverse Ranges in central California. This ophiolite, and other ophiolite remnants with similar mid-Jurassic ages, represent a major but short-lived episode of oceanic crust formation that affected much of western North America. The history of this ophiolite is important for models of the tectonic evolution of western North America during the Mesozoic, and a range of conflicting interpretations have arisen. Current petrologic, geochemical, stratigraphic, and radiometric age data all favor the interpretation that the Coast Range ophiolite formed to a large extent by rapid extension in the forearc region of a nascent subduction zone. Closer inspection of these data, however, along with detailed studies of field relationships at several locales, show that formation of the ophiolite was more complex, and requires several stages of formation. Our work shows that exposures of the Coast Range ophiolite preserve evidence for four stages of magmatic development. The first three stages represent formation of the ophiolite above a nascent subduction zone. Rocks associated with the first stage include ophiolite layered gabbros, a sheeted complex, and volcanic rocks vith arc tholeiitic or (roore rarely) low-K calc-alkaline affinities. The second stage is characterized by intrusive wehrlite-clinopyroxenite complexes, intrusive gabbros, Cr-rich diorites, and volcanic rocks with high-Ca boninitic or tholeiitic ankaramite affinities. The third stage includes diorite and quartz diorite plutons, felsic dike and sill complexes, and calc-alkaline volcanic rocks. The first three stages of ophiolite formation were terminated by the intrusion of mid-ocean ridge basalt dikes, and the eruption of mid-ocean ridge basalt or ocean-island basalt volcanic suites. We interpret this final magmatic event (MORB dikes) to represent the collision of an active spreading ridge. Subsequent reorganization of relative plate motions led to sinistral transpression, along with renewed subduction and accretion of the Franciscan Complex. The latter event resulted in uplift and exhumation of the ophiolite by the process of accretionary uplift.

California↗
USGS1997

Natural disasters: forecasting economic and life losses

Events such as hurricanes, earthquakes, floods, tsunamis, volcanic eruptions, and tornadoes are natural disasters because they negatively impact society, and so they must be measured and understood in human-related terms. At the U.S. Geological Survey, we have developed a new method to examine fatality and dollar-loss data, and to make probabilistic estimates of the frequency and magnitude of future events. This information is vital to large sectors of society including disaster relief agencies and insurance companies.

Fact Sheet↗