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University of Nebraska - Lincoln

1997

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Articles 31 - 60 of 555

Full-Text Articles in Life Sciences

Diet Of The Double-Crested Cormorant In Western Lake Erie, Michael T. Bur, Sandra L. Tinnirello, Charles D. Lovell, Jeff T. Tyson Dec 1997

Diet Of The Double-Crested Cormorant In Western Lake Erie, Michael T. Bur, Sandra L. Tinnirello, Charles D. Lovell, Jeff T. Tyson

Symposium on Double-Crested Cormorants: Population Status and Management Issues in the Midwest

Sport and commercial fishing interest groups are concerned about potential impacts double-crested cormorants (Phalacrocorax auritus) may have on fish species. Our objectives for this study were to determine the diet of the cormorant in western Lake Erie and the diet overlap and competition for resources with piscivorous fish, such as walleye (Stizostedion vitreum.) The stomach contents of 302 double-crested cormorants collected in western Lake Erie consisted primarily of young-of-the-year gizzard shad (Dorosoma cepedianum), emerald shiner (Notropis atherinoides,) and freshwater drum (Aplodinotus grunniens). In the spring, freshwater drum were the most …


Double-Crested Cormorant Impacts On Sport Fish: Literature Review, Agency Survey, And Strategies, John L. Trapp, Stephen J. Lewis, Diane M. Pence Dec 1997

Double-Crested Cormorant Impacts On Sport Fish: Literature Review, Agency Survey, And Strategies, John L. Trapp, Stephen J. Lewis, Diane M. Pence

Symposium on Double-Crested Cormorants: Population Status and Management Issues in the Midwest

In response to concerns expressed by anglers, the U.S. Fish and Wildlife Service conducted an extensive review of published studies done throughout the United States and Canada on the impacts of double-crested cormorants (Phalacrocorax auritus) on sport-fish populations in open waters. The literature review indicated that fish species valued by sport and commercial anglers make up a very small proportion of the cormorants’ diet and that these birds have a minor effect on fish populations compared to the effects of sport and commercial fishing, natural predation, and other mortality factors. The Service sent a questionnaire to State agencies, …


Strategies To Reduce Double-Crested Cormorant Depredation At Aquaculture Facilities In Mississippi, David S. Reinhold, Charles A. (Bo) Sloan Dec 1997

Strategies To Reduce Double-Crested Cormorant Depredation At Aquaculture Facilities In Mississippi, David S. Reinhold, Charles A. (Bo) Sloan

Symposium on Double-Crested Cormorants: Population Status and Management Issues in the Midwest

Double-crested cormorant (Phalacrocorax auritus) depredation throughout the Southeastern United States has been on the increase over the past 20 years. The increase in depredation coincides with the growth of the aquaculture industry and an expansion of double-crested cormorant wintering populations throughout the Southeast. The U.S. Department of Agriculture–Animal and Plant Health Inspection Service–Wildlife Services plays a major role in reducing double-crested cormorant damage. Nonlethal harassment on farms, dispersal from night roosts, and lethal control have reduced double-crested cormorant depredation at aquaculture farms in Mississippi. However, the efficiency and compatibility of current methods of reducing double-crested cormorant depredation must …


Possible Effects Of Catfish Exploitation On Overwinter Body Condition Of Double-Crested Cormorants, James F. Glahn, Mark E. Tobin, J. Brent Harrel Dec 1997

Possible Effects Of Catfish Exploitation On Overwinter Body Condition Of Double-Crested Cormorants, James F. Glahn, Mark E. Tobin, J. Brent Harrel

Symposium on Double-Crested Cormorants: Population Status and Management Issues in the Midwest

Concurrent with the rapid growth of the Mississippi catfish industry during the 1980’s, there was evidence of similar growth of double-crested cormorant (Phalacrocorax auritus) populations wintering in the delta region of Mississippi. Observational and food habits studies indicate that this expansive industry, incorporating more than 100,000 acres of ponds, provides an enormous food base for overwintering populations estimated in recent years to exceed 50,000 birds. As much as 75 percent of the diet in certain roosting areas of the Mississippi delta consisted of catfish, and according to bioenergetic models cormorants can exploit as much as 940 metric tons …


A Geographic Information System To Monitor Nest Distributions Of Double-Crested Cormorants And Black-Crowned Night-Herons At Shared Colony Sites Near Toronto, Canada, S. Jarvie, H. Blokpoel, T. Chipperfield Dec 1997

A Geographic Information System To Monitor Nest Distributions Of Double-Crested Cormorants And Black-Crowned Night-Herons At Shared Colony Sites Near Toronto, Canada, S. Jarvie, H. Blokpoel, T. Chipperfield

Symposium on Double-Crested Cormorants: Population Status and Management Issues in the Midwest

In the early 1990’s, it became apparent that the rapid colonization of Tommy Thompson Park on Lake Ontario near Toronto by double-crested cormorants (Phalacrocorax auritus) would eventually affect the existing colonies of blackcrowned night-herons (Nycticorax nycticorax) owing to competition for nest sites and destruction of nest trees. As a result, monitoring of these two species was expanded in 1992 by individually marking all nest trees (using permanent metal tree tags) and by recording the numbers of heron and cormorant nests for all nest trees. In 1996, professional surveyors determined the exact locations of nest trees. We have developed …


Colonial Waterbird Nesting On West Sister Island National Wildlife Refuge And The Arrival Of Double-Crested Cormorants, Mark C. Shieldcastle, Larry Martin Dec 1997

Colonial Waterbird Nesting On West Sister Island National Wildlife Refuge And The Arrival Of Double-Crested Cormorants, Mark C. Shieldcastle, Larry Martin

Symposium on Double-Crested Cormorants: Population Status and Management Issues in the Midwest

Recent survey data have shown the importance of West Sister Island National Wildlife Refuge, Lake Erie, to nesting waders. About 40 percent of all herons and egrets nesting in the U.S. Great Lakes are found there, including the Great Lakes’ largest colonies of great blue heron (Ardea herodias), great egret (Ardea alba), and black-crowned nightheron (Nycticorax nycticorax), and the largest of two snowy egret (Egretta thula). West Sister Island’s importance to Ohio has grown in recent decades with the loss of smaller mainland colonies of waders, especially the black-crowned night-heron. The double-crested …


Appendix 1: Authors' Affiliations Dec 1997

Appendix 1: Authors' Affiliations

Symposium on Double-Crested Cormorants: Population Status and Management Issues in the Midwest

Authors' affiliations


Double-Crested Cormorants In The Midwest: Symposium Summary, Francesca J. Cuthbert Dec 1997

Double-Crested Cormorants In The Midwest: Symposium Summary, Francesca J. Cuthbert

Symposium on Double-Crested Cormorants: Population Status and Management Issues in the Midwest


Populations of double-crested cormorants (DCCO’s, Phalacrocorax auritus) have increased dramatically in North America during the past 2 decades (1978–98), especially in the Great Lakes region and Southeastern United States. Concern about the impact, real or imagined, of DCCO’s on economics and ecosystem health has risen in parallel to the increase in cormorant numbers.

A daylong symposium on this subject was opened by Stephen Lewis and D. V. (Chip) Weseloh, who introduced the audience to the general problems associated with cormorants in the Midwest. The moderators identified the following symposium objectives: (1) to provide current information on the status and …


Fish Losses To Double-Crested Cormorant Predation In Eastern Lake Ontario, 1992–97, Robert M. Ross, James H. Johnson Dec 1997

Fish Losses To Double-Crested Cormorant Predation In Eastern Lake Ontario, 1992–97, Robert M. Ross, James H. Johnson

Symposium on Double-Crested Cormorants: Population Status and Management Issues in the Midwest

We examined 4,848 regurgitated digestive pellets of double-crested cormorants (Phalacrocorax auritus) over a 6-year period (1992–97) to estimate annual predation on sport and other fishes in the eastern basin of Lake Ontario. We found more than 51,000 fish of 28 species. Using a model that incorporates annual colony nest counts; fledgling production rates; adult, immature, and young-of-year residence times (seasonal); estimates of mean number of fish per pellet and mean fish size; and a fecal pathway correction factor (4.0 percent), we estimate total annual number of fish consumed by cormorants in the eastern basin of Lake Ontario to …


Review Of The Population Status And Management Of Double-Crested Cormorants In Ontario, C. Korfanty, W.G. Miyasaki, J.L. Harcus Dec 1997

Review Of The Population Status And Management Of Double-Crested Cormorants In Ontario, C. Korfanty, W.G. Miyasaki, J.L. Harcus

Symposium on Double-Crested Cormorants: Population Status and Management Issues in the Midwest

We prepared this review of the status and management of double-crested cormorants (Phalacrocorax auritus) in Ontario, with management options, in response to concerns expressed about possible negative impacts of large numbers of the birds on fish stocks, and vulnerable, threatened and endangered species. Double-crested cormorants are native to Ontario and were first recorded breeding on Lake of the Woods in northwestern Ontario in the late 1700’s. The birds spread eastward to colonize all of the Great Lakes by the 1930’s. A decline in cormorant populations on the Great Lakes from the 1950’s to the 1970’s has been attributed …


Information Needs For The Double-Crested Cormorant In Midwestern North America, As Identified By An Audience Survey , D.V. (Chip) Weseloh, Stephen J. Lewis Dec 1997

Information Needs For The Double-Crested Cormorant In Midwestern North America, As Identified By An Audience Survey , D.V. (Chip) Weseloh, Stephen J. Lewis

Symposium on Double-Crested Cormorants: Population Status and Management Issues in the Midwest

Double-crested cormorant (DCCO) research needs and data gaps were identified in the early 1990’s by Erwin (1995) and Nisbet (1995). Erwin (1995) recommended four areas of research: (1) large-scale banding and marking to determine age- and sex specific survival and fecundity, (2) studies of movements during migration and winter, (3) assessment of limiting factors such as contaminants and disease, especially in light of recent Newcastle disease in cormorants, and (4) evaluation of economic impacts of cormorants on cultured fishes and ways to reduce predation by fish-eating birds.


Basic Immunology, Lynn F. Woodward Dec 1997

Basic Immunology, Lynn F. Woodward

Range Beef Cow Symposium

The immune system can be thought of as a surveillance system to discriminate between “self" and "non-self." From simple life forms such as insects to advanced life forms such as humans, all living organisms have some form of host defense mechanism. Most have multiple, overlapping mechanisms ranging from very non-specific resistance to highly specific immunity. White blood cells forming "pus" around a splinter is representative of non-specific host resistance to invasion while immunity to IBR virus after vaccination or following recovery from active infection is representative of specific active immunity.

These host defense systems protect livestock and man from the …


Breeding For Profit: An Introduction To Selection Index Concepts, M. D. Macneil, R. A. Nugent, W. M. Snelling Dec 1997

Breeding For Profit: An Introduction To Selection Index Concepts, M. D. Macneil, R. A. Nugent, W. M. Snelling

Range Beef Cow Symposium

The selection problem, that of choosing which individuals become parents, is inherent in all of beef production. This problem almost invariably involves evaluating animals on more than one trait and making compromises among traits to arrive at a final evaluation of each candidate for selection. In a capitalist society, profitability seems a logical unit of expression for that final evaluation. It is certainly the basis of evaluation intended in the original development of selection index in the animal sciences (Hazel and Lush, 1942; Hazel, 1943). Thus, a desire on the part of producers to maximize profitability is assumed throughout this …


Ingestion Of Ponderosa Pine Needles By Cattle, S. L. Kronberg, R. E. Short, E. E. Grings Dec 1997

Ingestion Of Ponderosa Pine Needles By Cattle, S. L. Kronberg, R. E. Short, E. E. Grings

Range Beef Cow Symposium

Given the relatively high fiber and moderate crude protein concentrations in Ponderosa pine needles (Adams et al., 1992; Pfister et al., 1992) and their potential negative effect on organic matter digestibility and nitrogen retention in ruminants (Adams et al., 1992), it is not readily apparent why cattle eat them. However, there are a number of ideas that may help explain why they do. Ponderosa pine needles contain a variety of nutrients and precursors including glucose, fructose, galactose, sucrose, citric acid, shikimic acid (a precursor in the biosynthesis of the amino acids phenylalanine, tyrosine and tryptophan), crude protein (Pfister et al., …


Synchronization Programs Update, Tom Geary Dec 1997

Synchronization Programs Update, Tom Geary

Range Beef Cow Symposium

Synchronization of estrus involves methods of manipulating the estrous cycle of females within a herd so they express estrus at approximately the same time. There are several traditional protocols available for synchronizing estrus (heat) among beef cows. Traditional protocols include one or two Prostaglandin protocols, the MGA/prostaglandin protocol and the Syncro- Mate B protocol. None of these methods have been universally adopted because none are able to satisfy all situations. There are also a couple of new protocols that have been developed within the last 2 years that have resulted in higher success than traditional protocols. These new protocols include …


Factors Affecting Calf Survival, R. A. Bellows Dec 1997

Factors Affecting Calf Survival, R. A. Bellows

Range Beef Cow Symposium

Survival of the calf at or shortly after birth can be compromised leading to high death losses and a serious impact on net income for the cattle producer. This paper will briefly review some findings related to causes of death of the newborn calf.


Cows And Computers: Choosing Records Management Software, Martha Malm Ellis Dec 1997

Cows And Computers: Choosing Records Management Software, Martha Malm Ellis

Range Beef Cow Symposium

Back in 1990, those of us at Malm Ranch Company decided it was becoming more and more difficult to keep accurate records on over 800 head of cows using the paper/pencil method-- especially when the "paper" ended up being the inside of boxes from our vaccines and Ivomec! So when my two kids and I returned to work at the ranch full time, I was given the job of computerizing the cattle records for our family farming/ranching operation. I started out using a data base program but soon found myself having to enter the same information over and over because …


Computer Software Selection: Financial, Kory M. Bierle Dec 1997

Computer Software Selection: Financial, Kory M. Bierle

Range Beef Cow Symposium

Over and over we as producers are told we need to know our cost of production. As the title of my college accounting book stated, accounting is the basis for business decisions.

The question comes up: how do we track these costs and make sense of all the numbers? As soon as we realize the importance of the office work and the need to get it done in a timely and efficient manner, we address how to get it done. What has been the answer for the past 20 to 25 years to help get the work done? That's right, …


Characterization Of Alliances, Mike Miller Dec 1997

Characterization Of Alliances, Mike Miller

Range Beef Cow Symposium

Content:

Today’s Cattle Market

Future Cattle Market

“Average” Grid

The Target

“Value” Checklist

Factors to Consider

Potential Trade Offs

The Bottom Line: Does It Increase Profit


Carcass Value Marketing, Dick Kjerstad Dec 1997

Carcass Value Marketing, Dick Kjerstad

Range Beef Cow Symposium

A. Importance of individual source identification as it relates to carcass value

B. Criteria for USDA Quality Grades

C. Criteria for USDA Yield Grades


Innovative Marketing And Angus America, Douglas Hoff Dec 1997

Innovative Marketing And Angus America, Douglas Hoff

Range Beef Cow Symposium

Marketing sounds easy, right? All that you have to do is sell when the market is high and buy when it's low. The problem is that only God could accomplish this! Even if we had the time to do the research required to make these predictions they're still, at best, only educated guesses. How does a cow/calf producer market in an innovative manner when he only has the option to go to a sale barn, an order buyer, or a feedlot with his years' work, just to get the same average price?


New National Research Council (Nrc) Beef Cattle Requirements - Range Application, Ivan G. Rush Dec 1997

New National Research Council (Nrc) Beef Cattle Requirements - Range Application, Ivan G. Rush

Range Beef Cow Symposium

Beef producers have used experience and guidelines for many years to determine proper level of nutrition for their cow herd. In the early 1900s, research started to compare various feeding programs to determine which feeds or supplements worked best, and then comparisons were made on various levels of supplements to determine how much supplement was needed. In the 1920s, considerable research was conducted at the Valentine, Nebraska Experiment Station (no longer in existence) to see if calves wintered on sandhills range would benefit from cottonseed cake (cottonseed meal was large chunks or "cake" in the 1920s), and a series of …


Applications Of Monitoring For Producers, Roy Roath Dec 1997

Applications Of Monitoring For Producers, Roy Roath

Range Beef Cow Symposium

The context in which rangeland livestock enterprises operate is changing in the United States. Economic pressures, markets, agency policies, and greater environmental awareness are challenging range livestock operators to mange their operations mare effectively and to respond to meet the challenges of the question "Are you a good steward of the land?" being posed by friend and foe, alike. This debate on land management practices is increasing. Much of this discussion is focusing on conflicts between the multiple uses of the resource. This affects the western livestock industry in a major way because the industry will be judged on its …


Cow/Calf Analysis: Key Indicators Of Profitability, Don Boggs, Eddie Hamilton Dec 1997

Cow/Calf Analysis: Key Indicators Of Profitability, Don Boggs, Eddie Hamilton

Range Beef Cow Symposium

Which of the following herds is more profitable: herd A that weans a 90% calf crop of 450 lb. calves that go on to grade 60% Choice or herd B that weans a 95% calf crop of 600 lb. calves that go on to grade 80% Choice? Obviously the question can not be answered with the information at hand. We have only the output side of the profitability equation and none of the inputs. It is likely that herd B will generate more revenue, but without knowing the costs of producing that revenue we can never know which herd is …


Hyaluronan Synthase Of Chlorella Virus Pbcv-1, Paul L. Deangelis, Wei Jing, Michael V. Graves, Dwight E. Burbank, James L. Van Etten Dec 1997

Hyaluronan Synthase Of Chlorella Virus Pbcv-1, Paul L. Deangelis, Wei Jing, Michael V. Graves, Dwight E. Burbank, James L. Van Etten

Department of Plant Pathology: Faculty Publications

Sequence analysis of the 330-kilobase genome of the virus PBCV-1 that infects a chlorella-like green algae revealed an open reading frame, A98R, with similarity to several hyaluronan synthases. Hyaluronan is an essential polysaccharide found in higher animals as well as in a few pathogenic bacteria. Expression of the A98R gene product in Escherichia coli indicated that the recombinant protein is an authentic hyaluronan synthase. A98R is expressed early in PBCV-1 infection and hyaluronan is produced in infected algae. These results demonstrate that a virus can encode an enzyme capable of synthesizing a carbohydrate polymer and that hyaluronan exists outside of …


Ard News December 1997 Dec 1997

Ard News December 1997

Agricultural Research Division: News and Annual Reports

CONTENTS:

SEASON'S GREETINGS
CSREES Accountability Report Status
External Grant Support
Federal Research and Development Funding for FY 1998
FY 1998 Appropriation for CSREES Research
Proposals Submitted for Federal Grants
Grants and Contracts Received October and November, 1997
New or Revised Projects
Free Publication on Highlights of NAPIAP
Superfund Cleanup Progress at the ARDC
World Rankings of Scientific Papers


Nebraska Bird Review (December 1997) 65 (4), Whole Issue Dec 1997

Nebraska Bird Review (December 1997) 65 (4), Whole Issue

Nebraska Bird Review

Whooping Crane Sightings, August 1997-January 1998 … 146

A Probable Nesting of Clark's Nutcracker (Nucifraga columbiana) in Nebraska … 147

Notes on the Nesting Biology of Pygmy Nuthatches in Nebraska … 150

Fall Field Report, August-November 1997 … 159

Observers for Fall Field Report … 178

Black-throated Sparrow Banded in Omaha, Nebraska … 179

Editor's Comments … 179

Index to Volume 65 (compiled by R. G. Cortelyou) … 180


Calculation Of Breed Direct And Maternal Genetic Fractions And Breed Specific Direct And Maternal Heterozygosity For Crossbreeding Data, L. Dale Van Vleck Dec 1997

Calculation Of Breed Direct And Maternal Genetic Fractions And Breed Specific Direct And Maternal Heterozygosity For Crossbreeding Data, L. Dale Van Vleck

Department of Animal Science: Faculty Publications

Teaching, research, and herd breeding applications may require calculation of breed additive contributions for direct and maternal genetic effects and fractions of heterozygosity associated with breed specific direct and maternal heterosis effects. These coefficients can be obtained from the first NB rows of a pseudo numerator relationship matrix where the first NB rows represent fractional contributions by breed to each animal or group representing a specific breed cross. The table begins with an NB x NB identity matrix representing pure breeds. Initial animals or representative crosses must be purebreds or two-breed crosses. Parents of initial purebreds are represented by the …


A Probable Nesting Of Clark's Nutcracker (Nucifraga Columbiana) In Nebraska,, Wayne Mollhoff Dec 1997

A Probable Nesting Of Clark's Nutcracker (Nucifraga Columbiana) In Nebraska,, Wayne Mollhoff

Nebraska Bird Review

This report provides details on the probable nesting of Clark's Nutcracker (Nucifraga columbiana) in Morrill, Scotts Bluff Co., Nebraska, in 1997. It also corrects an erroneous report of nesting in the Pine Ridge area of Nebraska (Silcock & Jorgensen 1997b).

A single Clark's Nutcracker was first noted corning to a suet feeder at the home of Ms. Edna C. Thomas in Morrill 8-9 Jan 1997. It came to the feeder at least weekly and was often seen daily. A second Clark's Nutcracker appeared during the second week of Feb. Initially, the bird already present was antagonistic towards it …


Black-Throated Sparrow Banded In Omaha, Nebraska, Ruth C. Green Dec 1997

Black-Throated Sparrow Banded In Omaha, Nebraska, Ruth C. Green

Nebraska Bird Review

On 20 December 1997, I banded a Black-throated Sparrow in the vicinity of 43rd and J Streets in South Omaha, Nebraska. The band number on this bird is 2120/83856. It was an AHY-Male and, according to the description given by James D. Rising in his book, A Guide to the Identification and Natural History of the Sparrows of the United States and Canada, it was of the subspecies Amphispiza b. bilineata. This is the smallest of the three races found in the united States and it is indigenous to central Texas. Besides the smaller size, the identifying field …