Ecology and Evolutionary Biology Commons^™

Lake Mead Prefertilization Study: Preliminary Nutrient Enhancement Studies In Lake Mead, Richard P. Axler, Larry J. Paulson, Patrick J. Sollberger, Donald H. Baepler, U.S. Bureau Of Reclamation

Publications (WR)

Studies conducted by the University of Nevada-Las Vegas (UNLV), the Nevada Department of Wildlife (NDOW), the Arizona Game and Fish Department (AGFD), The Nevada Division of Environmental Protection (NDEP), and the United States Bureau of Reclamation (USBR) have identified decreased algal production as a major factor involved in the decline of the Lake Mead sport fishery. Phosphorus-laden silt particles in the Colorado River have been sedimenting out in Lake Powell since the completion of Glen Canyon Dam 286 miles upstream in 1963. This sharp decrease in phosphorus loading to Lake Mead (>5000 tons per year) has resulted in decreased …

Use Of Woody Vegetation By Beavers In Southeastern Virginia, John L. Echternach, Robert K. Rose

Biological Sciences Faculty Publications

Nonbreeding and sometimes transient beavers, Castor canadensis, cut a variety of woody plants throughout the year during a 15-month study at three sites in southeastern Virginia. Ten species of trees were cut in proportions greater than would be expected according to their availabilities. Beavers heavily used viburnum, alder, ironwood, bayberry, tulip poplar, and dogwood. Winter food caches were constructed but were only lightly used.

Report Of The Rock Lobster Industry Advisory Committee To The Hon. Minister For Fisheries., Rock Lobster Industry Advisory Committee

Fisheries Management Papers

The Committee recognises that the exploitation rate on the rock lobster stocks is very high and that this factor is a major importance in formulating the advice on management measures. However, the Committee also recognises the high level of capital investment in the industry and that any recommendation which leads to a significant change in the management rules is likely to have a far reaching effect on many of the participants. Accordingly, the Committee endeavours to reduce to a minimum the year to year changes in the management rules. When changes are required the Committee places considerable weight on matters …

Benthic Invertebrates And Crayfish Of Lake Mead, Susan K. Peck, William L. Pratt, James E. Pollard, Larry J. Paulson, Donald H. Baepler

Publications (WR)

The objectives of this study were to:

1. Establish baseline densities of benthic invertebrates and relative abundance of crayfish in Lake Mead.

2. Evaluate the distributions of benthic organisms and crayfish in relation to existing habitat conditions and 1imnological characteristics of Lake Mead.

3. Measure seasonal changes in abundances of benthic organisms and crayfish in Lake Mead.

4. Compare observations of Procambarus clarkii life history in Lake Mead to reports from other aquatic systems.

5. Evaluate the importance of benthic organisms and crayfish as food sources for game fish in Lake Mead.

Comparison Of Littoral And Limnetic Zooplankton Communities Of Lake Mead, Patrick Joseph Sollberger

Publications (WR)

Microfaunal communities were studied in littoral (inshore) and limnetic (offshore) areas of the lower basin in Lake Mead to compare species composition and abundance between the two zones. Planktonic forms (zooplankton) dominated inshore and offshore habitats and the occurrence of littoral species was low. Therefore, high similarity in zooplankton species composition was found among all sampling stations. This was perhaps due to two main factors: (i) the physical and chemical environment among the stations were very similar and (ii) the lack of aquatic vegetation in the littoral zone reduced the occurrence of littoral species.

Although species composition did not vary …

Behavioral Feeding Specialization In Pinaroloxias Inornata, The “Darwin's Finch” Of Cocos Island, Costa Rica, Tracey K. Werner, Thomas W. Sherry

Dartmouth Scholarship

As a population, Cocos Finches exhibit a broad range of feeding behaviors spanning those of several families of birds on the mainland, while individuals feed as specialists year-round. Although this extreme intraspecific variability occurs as predicted in a tropical oceanic island environment, these specializations challenge contemporary ecological theory in that they are not attributable to individual differences in age, sex, gross morphology, or opportunistic exploitation of patchy resources. Instead, they appear to originate and be maintained behaviorally, possibly via observational learning. This phenomenon adds another direction to the evolutionary radiation of the Darwin's Finches and underscores the necessity for detailed …

Book Review Of Evolution As Religion, Carl J. Bajema

Other Scholarly Publications

No abstract provided.

Western Rock Lobster Industry Compensation Study. Report To The Rock Lobster Industry Advisory Committee By Arthur Young Services., Arthur Young Services

Fisheries Management Papers

Terms of reference are outlined in letter dated 11 August 1986. The Fisheries Department seeks to reduce western rock lobster fishing capacity to ensure the long-term viability of the fishery and has asked us to evaluate the financial implications of a number of specific resource management proposals.

Report Of The Rock Lobster Industry Advisory Committee Meeting Of 27 January 1987 - Report By The Chairman Mr. B.K. Bowen., B. K. Bowen

Fisheries Management Papers

The Rock Lobster Industry Advisory Committee met in Perth on Tuesday 17 January 1987. Committee discussed the following: Policy on 5% pot loss on replacement of vessels less than six years old. Study of industry funded compensation mechanism for fishing capacity reductions. 20 Fathom rule. Future maintenance of the zone E boundary. The recreational Rock Lobster Fishery. Rock Lobster pot distribution. Options for a 10 per cent reduction in fishing effort. 1987 coastal tour. Augusta-Windy Harbour Rock Lobster Working Group. Report on the 1986/87 season.

Specimen Catalog, Joseph A. Cook

Division of Mammals - Field Notes and Catalogs

No abstract provided.

Distribution And Current Status Of The Threatened Dismal Swamp Southeastern Shrew, Sorex Longirostris Fisheri, Robert K. Rose, Roger K. Everton, Thomas M. Padgett

Biological Sciences Faculty Publications

The Dismal Swamp southeastern shrew, Sorex longirostris fisheri, was given "Threatened" status by the U.S. Fish and Wildlife Service in 1986 because of its limited distribution and the potential threat of interbreeding with the nearby upland subspecies, Sorex l. longirostris. Known from about 20 specimens collected before 1980 and a few dozen taken since then, "fisheri" seems to have morphologically diverged from the smaller upland "longirostris" in association with the development of the Dismal Swamp. The detection of southeastern shrews that are intermediate in size between the two subspecies, coupled with the location of these collection sites on …

The Identification Of The Threatened Southeastern Shrew Using Multivariate Statistical Techniques, Thomas M. Padgett, Roger K. Everton, Robert K. Rose

Biological Sciences Faculty Publications

The threatened subspecies of the southeastern shrew, Sorex longirostris fisheri, is endemic to the Great Dismal Swamp of southeastern Virginia. Previous studies based on discriminant analysis of external measurements determined that intergrades with the upland form, Sorex l. longirostris, exist along the periphery of the Swamp. To better discriminate among these populations, a study of cranial morphology was initiated. Fifteen cranial measurements were taken, using 59 specimens of Sorex collected previously form southeastern Virginia, including the Dismal Swamp. Both Principal Component and Cluster Analyses revealed no significant cranial variation or morphometric patterns within the specimens examined, but a …

Specimen Catalog, Forrest W. Davis

Division of Mammals - Field Notes and Catalogs

No abstract provided.

Field Notes, Joseph A. Cook

Division of Mammals - Field Notes and Catalogs

No abstract provided.

Miscellaneous Notes, William L. Gannon

Division of Mammals - Field Notes and Catalogs

No abstract provided.

The Windy Harbour-Augusta Rock Lobster Working Group. Interim Report By The Chairman Mr. A. Pallot To The Western Australian Fishing Industry., A. Pallot

Fisheries Management Papers

Summary of Recommendations: Boat Access: That the Windy Harbour-Augusta Rock Lobster Fishery be declared a limited entry fishery. That the limited entry fishery related to the taking of Western Rock Lobster (Panulirue cygnus) and Southern Rock Lobster (Jasus novaehollandiae) That the southern boundary of Zone E of the W.C.R.L.F. terminate at a point where it intersects with a line drawn in a southerly direction from the Cape Leeuwin lighthouse. That the eastern boundary remain at Point D'Entrecasteaux (approximately 1160east longitude). That the western and southern boundaries by limits of the Australian Fishing Zone. That the season be for the period …

Bird Use Of Lakes In The Claremont-Upland Area, Valerie Banschbach

Pomona Senior Theses

I studied water bird use of two lakes in the Claremont-Upland area to determine what physical, chemical, and biological aspects of these lakes provide suitable water bird habitat and food resources. I censused the Bernard Field Station Lake in Claremont and a gravel pit freshwater area in Upland from 10/85 to 3/86 for water bird use. I also mapped these sites, noted their water surface area and water depth changes, monitored their water chemistry, and censused their vegetation. The results of this work showed more total water birds per hour of observation time, and more birds per hour of observation …

Life History And Production Of Three Species Of Isopods In Beargrass Creek Louisville, Ky, James A. Eckstein

Electronic Theses and Dissertations

The life history and annual production of the aquatic isopods L. fontinalis, C. intermedia and C. brevicaudus in a spring stream, Beargrass Creek, Louisville, Kentucky was studied. Reproductive activity was observed with the greatest intensity in the spring months from March to May. Smaller secondary peaks for recruitment of young were seen in the fall months for L. fontinalis and C. intermedia. Brood size for the three isopods was compared by linear regression. The mean annual biomass for the three isopods ranged from 0.67 g/m2 for C. intermedia, 0.83 g/m2 for C. brevicaudus to 2.1 g/m2 for L. fontinalis. Annual …

Genetic Engineering, W. John Hayden

Biology Faculty Publications

Why do so many biologists express so little concern for biology as a whole and such contempt for fields other than their own? The current debate on release of genetically engineered organisms into the environment, specifically, J. E. Fox's recent reply (Letters, 18 Oct., p. 237) to an earlier letter by R. K. Colwell et al. (12 July, p. 111), offers a case in point.

Reproductive Strategies Of Meadow Voles, Hispid Cotton Rats, And Eastern Harvest Mice In Virginia, Robert K. Rose

Biological Sciences Faculty Publications

Patterns of reproduction in small mammals in Virginia were examined by autopsying samples of meadow voles (Microtus pennsylvanicus) collected for 23 months near Charlottesville, of hispid cotton rats (Sigmodon hispidus) collected for 14 months in Portsmouth, and by evaluating live-caught eastern harvest mice (Reithrodontomys humulis) trapped for 15 months in Suffolk and for 12 months in Chesapeake. The meadow vole, a microtine rodent with a north temperate and sub-arctic distribution throughout North America, suspended breeding during the winter of peak density but not of declining density. High metabolic rates and other adaptations for winter …

Specimen Catalog, Part 1, Brian D. Frank

Division of Mammals - Field Notes and Catalogs

No abstract provided.

Specimen Catalog, James S. Findley

Division of Mammals - Field Notes and Catalogs

No abstract provided.

Field Notes, James S. Findley

Division of Mammals - Field Notes and Catalogs

No abstract provided.

Biotic Interactions Among Estuarine Infaunal Opportunistic Species, Roman Zajac, R. B. Whitlatch

Biology and Environmental Science Faculty Publications

Biotic interactions among soft-sediment infauna were investigated in a small New England estuary in order to determine what effect(s) established opportunistic species had on subsequent recolonization. Interactions were defined according to successional models developed by Connell and Slatyer (1977), e.g. facilitation, tolerance and inhibition. Adults of the opportunistic polychaetes Streblospio benedicti, Polydora ligni and Hobsonia florida were added at 2 densities to separate cores containing defaunated sediment. These cores and control cores containing no worms were sampled at 10 d intervals for 40 d. Cores containing capillary tubes to simulate polychaete tubes were also deployed and sampled at 10 d …

Gametogenesis En Chthonerpeton Indistinctum (Gymnophiona: Typhlonectidae), Rafael O. De Sá, Nibia Berois

Biology Faculty Publications

RESUMEN:

Histológicamente, las gónadas de Chthonerpeton indistinctum son similares a las ya descritas para otras especies del orden Gymnophiona. Los lóbulos testiculares se hallan compartimentados en unidades estructurales denominadas lóculos. La espermatogénesis ocurre en cistos sincrónicos de células germinales. Durante la espermiogénesis se identifican cuatro estados consecutivos de desarrollo: 1) cistos de espermátidas redondeadas; 2) cistos de espermátidas arrifionadas; 3) cistos de espermátidas bastoniformes y 4) espermátidas en ramillete.

El análisis histológico de los ovarios mostró la presencia de tres estados en la maduración de los folículos ováricos. Estas etapas pueden ser identificadas de acuerdo a: 1) ubicación del folículo …

Community Ecology, Robert K. Rose, Elmer C. Birney

Biological Sciences Faculty Publications

COMMUNITIES with Microtus tend to be structurally simple, usually grasslands or tundra, and to have no more than two species of Microtus and rarely more than six species of small mammals. Microtus often dominates both numerically and in total small mammal biomass, especially at higher latitudes. The small mammal community is most influenced by Microtus through its fluctuations in density, and thus also in biomass, by its relatively high level of diurnal activity, and by its year-round activity. Other species of small mammals may be adversely affected because Microtus usually is larger and behaviorally dominant and also because the mere …

Estructura Del Ovario De Chthonerpeton Indistinctum (Reinhardt Y Lutken, 1862) (Amphibia: Gymnophiona) Durante La Gestación, Rafael O. De Sá, Nibia Berois

Biology Faculty Publications

La morfología e histología del ovario para varias especies del orden Gymnophiona ha sido reportada por Wake (1968, J. Morphol. 126, 291) y para C. indistinctum por los autores (1984, XXIV Reunión de Comunicaciones, Soc. Zool. Uruguay).

Continuando con los estudios sobre el aparato genital de esta especie vivípara, se presenta ahora la estructura del ovario durante la gestación.

Se procesaron con fines histológicos, ovarios de dos hembras grávidas colectadas en las costas de los Dep. Montevideo y San José en abril, 1983. El número de ejemplares trabajados es muy reducido dado lo difícil que resulta su colecta …

Benthic Diatom Community Dynamics In The Colorado River: Interactive Effects Of Periodic Dessication And Current Regime, Christopher Gerard Peterson

Publications (WR)

The response to periodic desiccation of periphyton communities developed in eddy environments or in areas exposed to variable, direct current was examined. Algal communities were incubated on clay tiles for between 2 and 12 weeks in the Colorado River, directly below Hoover Dam from October, 1983 - January, 1984. Mean daily discharge from the dam decreased over this period. To assess the influence of these discharge changes on community dynamics, samples collected over the first 12 weeks of the investigation were compared to samples of the same age collected over the final 8 weeks.

The small diatom taxon Achnahthes spp …

An Evaluation Of Naturally Occurring Populations Of Magnolia Tripetala L. In Indiana, Kemuel S. Badger

All-Inclusive List of Electronic Theses and Dissertations

Magnolia tripetala L. occurs in Indiana as a disjunct from the Appalachian mountains populations. Currently, the known distribution of ~· tripetala in Indiana is confined to seven sites in Crawford County. The current status of ~· tripetala and the surrounding plant community was evaluated to aid in the future study, protection and management of this species, which is endangered in Indiana. Systematic random sampling of the tree stratum was done with belt transects. The sapling and seeding strata were sampled with subplots, placed along the belt transects. Permanent plots were established to enable future monitoring of what is currently prime …

The Role Of Colonization Predation And Season In Determining Macroinvertebrate Community Structure In A Temperate Lake, Cheryl Lynn Frew

Biological Sciences Theses & Dissertations

Field experiments were conducted to examine the effects of distance from shore, vertebrate predation, and season on macroinvertebrate colonization dynamics in a temperate lake in Suffolk, VA. In a year-long colonization study, artificial plants, half of which were caged to exclude vertebrate predators, were deployed in patches at three distances from shore (2m, 15m, 50m). Artificial plant subsamples were removed at weekly intervals over 28 days during four seasons to monitor colonization by macroinvertebrates. Colonization of artificial plants occurred more quickly in the summer and spring than in fall and winter. The interactive effect of distance from shore and cage …