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Publications

These publications showcase the significant science conducted in our Science Centers.

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Direct simulation of groundwater age Direct simulation of groundwater age

A new method is proposed to simulate groundwater age directly, by use of an advection-dispersion transport equation with a distributed zero-order source of unit (1) strength, corresponding to the rate of aging. The dependent variable in the governing equation is the mean age, a mass-weighted average age. The governing equation is derived from residence-time-distribution concepts for the...
Authors
Daniel J. Goode

Silt heavy-mineral distributions off the Southeastern United States Silt heavy-mineral distributions off the Southeastern United States

Until recently heavy-mineral studies of marine sediments were largely restricted to sand fractions. New techniques permitting analysis of decalcified silt fractions have been applied to sediments off the southeastern United States. Our data, which confirm predictions from the basic relationship among grain size, specific gravity, and equivalent hydraulic transport behavior, show that
Authors
L.J. Poppe, J.A. Commeau

Control of external Aeromonas salmonicida: topical disinfection of salmonids with Chloramine-T Control of external Aeromonas salmonicida: topical disinfection of salmonids with Chloramine-T

Brook trout Salvelinus fontinalis were treated with single 60-min static baths of 250 mg formalin/L, 3% NaCl, and 15 mg Chloramine-T/L to evaluate the efficacy of these compounds against external infections of Aeromonas salmonicida. Prevalence of A. salmonicida was significantly lower in brook trout treated with Chloramine-T than among those treated with formalin or salt. Further...
Authors
R. C. Cipriano, L.A. Ford, C. E. Starliper, J.D. Teska, J.T. Nelson, B.N. Jensen

Feeding ecology of larval and juvenile American shad (Alosa sapidissima) in a small pond Feeding ecology of larval and juvenile American shad (Alosa sapidissima) in a small pond

Release ponds are used as part of a multifacet effort to restore American shad (Alosa sapidissima) in the upper Susquehanna River basin. Little information exists, however, on the feeding ecology of young shad in small ponds. Consequently, we examined feeding ecology and prey selection of 299 larval and 299 juvenile American shad in a small pond during spring and summer. Larval shad...
Authors
J. H. Johnson, D. S. Dropkin

A passive integrated transponder (PIT) tag system for monitoring fishways A passive integrated transponder (PIT) tag system for monitoring fishways

An application of passive integrated transponder (PIT) technology was used to monitor movements of adult American shad (Alosa sapidissima), blueback herring (A. aestivalis) and gizzard shad (Dorosoma cepedianum) in two experimental fishways. Tag reading efficiency was between 88–96%, detection ranges were 50–100 cm from orifices of 3100–9600 cm2, and read rates were 5–7 Hz. The system...
Authors
Theodore R. Castro-Santos, Alexander Haro, S. Walk

Pellets versus feces: their relative importance describing the food habits of double-crested cormorants Pellets versus feces: their relative importance describing the food habits of double-crested cormorants

We compared the amount of taxonomically identifiable (diagnostic) fish remains in double-crested cormorant (Phalacrocorax auritus) feces to that exiting the birds via regurgitated pellets. Feces and pellets were collected concurrently during June 1994 from cormorant colonies on Little Galloo Island, eastern Lake Ontario. About 90% of the diagnostic fish remains were found in pellets and...
Authors
J. H. Johnson, R. M. Ross

Predicting watershed acidification under alternate rainfall conditions Predicting watershed acidification under alternate rainfall conditions

The effect of alternate rainfall scenarios on acidification of a forested watershed subjected to chronic acidic deposition was assessed using the model of acidification of groundwater in catchments (MAGIC). The model was calibrated at the Panola Mountain Research Watershed, near Atlanta, Georgia, U.S.A. using measured soil properties, wet and dry deposition, and modeled hydrologic...
Authors
Thomas G. Huntington

Survival of breeding male American woodcock in Maine Survival of breeding male American woodcock in Maine

The authors investigated the survival of breeding male American woodcock in Washington County, Maine. A total of 150 birds were radio-arked during 1987-1989 and relationships were evaluated between survival, body mass, predation, weather, and habitat use. Survival varied from 0.690 (1989) to 0.924 (1988), with a 3-year mean (95% confidence interval) of 0.789 (0.693-0.885)
Authors
J. R. Longcore, D.G. McAuley, G.F. Sepik, G.W. Pendleton

Productivity of the spruce grouse in fragmented habitat at the edge of its range Productivity of the spruce grouse in fragmented habitat at the edge of its range

We measured productivity of the Spruce Grouse (Dendragapusc anadensicsa nadensis) in patchy black spruce (Picea mariana) habitat along the southeastern limit of its range in mid-coastal Maine. We captured grouse and attached necklace-mounted radio transmitters to hens prior to nesting. Of 19 females monitored, only 26% raised chicks to the late brood-rearing period. Predation was high on...
Authors
S.D. Whitcomb, A.F. O'Connell, F. A. Servello
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