Digital Commons Network^™

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 …

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 …

Double-Crested Cormorant Culling In The St. Lawrence River Estuary: Results Of A 5-Year Program, J. Bedard, A. Nadeau, M. Lepage

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

Modeling indicated that lowering the doublecrested cormorant population from 17,361 to 10,000 pairs could be attained only by a combination of techniques: culling breeding birds in arboreal colonies to lower breeding stock and egg spraying in accessible ground nests to lower recruitment. The 5-year program was launched in 1989; culling was halted 4 years later because the population had fallen below the threshold of 10,000 breeding pairs. A greater vulnerability of males to shooting (203:100) probably accounted for the faster-than-predicted drop in numbers. Egg spraying spanned the entire 5-year period, during which 25,095 nests were treated with inert mineral oil. …

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 …

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 …

Calving Difficulty, Robert G. Mortimer

Range Beef Cow Symposium

The recognition of abnormal calving (dystocia) comes FIRST from a basic understanding of normal calving. From this understanding, the establishment of guidelines for observation of cattle and for intervention will reduce calf losses. In Colorado, as part of a pilot program of the National Animal Health Monitoring System (NAHMS), two-thirds of the costs of disease losses were associated with death loss. From a subset of 73 of the 86 NAHMS herds in studied in 1986- 87 in 24,396 births, 4.5% of the calves were lost. Of the 4.5% losses, 34% were attributed to dystocia related losses. In addition, losses attributed …

Empowering People, Burke Teichert

Range Beef Cow Symposium

Empowerment is a function of systems, attitudes and access. A ranching system is a grouping of subsystems which includes biological, climatic, business, financial and managerial processes. The system may be structured to enable and encourage or to impede empowerment of the team members. Access to ideas, research, training, tools, mentoring, modeling, etc. is vital to high level empowering. If the system is right, then the attitudes of the people involved will determine how much empowerment will take place.

Bosses and managers don't empower people. They enable and facilitate, but people at all levels of reporting are responsible for their own …

Addressing The Beef Tenderness Problem, Chris R. Calkins

Range Beef Cow Symposium

We've all heard time and again the importance of beef tenderness to customer satisfaction. Research continually supports this concept. In the Beef Customer Satisfaction report from the National Cattlemen's Beef Association, tenderness was highly correlated to consumer ratings of their satisfaction with the product (r=.85), as was flavor desirability (r=.86). Recent focus group participants in a session discussing beef quality were quick to identify tenderness as one of the primary descriptors to quality. There is no doubt that tenderness is a critical characteristic of beef and providing product which does not meet consumer expectations will definitely reduce satisfaction with the …

Realities Of Cow Herd Genetics: Expectations And Impact, Don Marshall

Range Beef Cow Symposium

Beef cattle production in the United States remains largely a segmented rather than integrated industry. The needs and goals of the various segments of the production chain, with respect to production specification targets, are often different and sometimes conflicting. The resulting inadequate response of the industry to consumer needs has occurred at the same time as intensified competition from pork and poultry products, each of which has contributed to the decline of beef consumption.

Seedstock and commercial cow-calf producers represent particularly important links in the beef production chain because they have primary control of the genetics and produce the ''raw …

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 …

Overview Of A Tqm Approach For Improving Beef Tenderness, J. D. Tatum, M. H. George, K. E. Belk, G. C. Smith

Range Beef Cow Symposium

Steers and heifers comprising the U.S. "fed" beef supply are highly variable in biological type, age, and management background (most are grain-finished, but they are started on feed at different ages, given different growth promoting implants, fed for differing periods of time, and slaughtered at different ages). The beef industry's current system for ensuring acceptable product tenderness involves "mass inspection" (USDA Quality Grading) of completed products (carcasses) at the end of the production process. Although this system results in general categorization according to tenderness differences, product value is lost due to inaccuracy of sorting methodology (Quality Grades account for approximately …

Reproductive Toxicology: Pine Needles And Plant Estrogens, R. E. Short, S. L. Kronberg, E. E. Grings, J. P. Rosazza, S. P. Ford

Range Beef Cow Symposium

Reproductive rate or efficiency, the number of live offspring produced from a herd of a specified number each year, is the main determinate of biological and economic efficiency of a beef cattle enterprise. Reproduction is a complex and continuous process that starts before birth and continues through puberty and a series of endocrine and behavioral events that include estrous cycles, breeding, conception, gestation, parturition, and lactation. The culmination of reproduction is live offspring produced for sale or for reentering the herd as replacements. Whenever any of these events are interfered with, reproductive rate and economic efficiency will decrease. In most …

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., …

Introduction To The Symposium On Double-Crested Cormorants: Population Status And Management Issues In The Midwest, Stephen J. Lewis, D.V. (Chip) Weseloh

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

Populations of double-crested cormorants (Phalacrocorax auritus) have increased dramatically in the last 2 decades, particularly in the Great Lakes and the Southeastern United States. Their food habits and propensity for killing the trees in which they nest and roost have made cormorants the subject of much controversy. Cormorants affect—or are perceived to affect—sport fishing, aquaculture operations, vegetation, and other colonial waterbirds. Anglers, aquaculturists, resort operators, lakehome owners, politicians, and others are calling for a solution to these problems. This symposium was convened to provide information that will help conservation agencies and others make sound resource management decisions about …

The Problems Of Being Successful: Managing Interactions Between Humans And Double-Crested Cormorants, Douglas Siegel-Causey

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

The natural history, behavior, and ecology of double-crested cormorants (Phalacrocorax auritus) predispose this species for conflict with human sport and commercial fisheries. Cormorants breed early in life, have large broods, are efficient predators even in marginal conditions, seem to be able to adjust colony sizes quickly in response to local conditions, and have limited requirements for feeding and nesting habitats. A survey of the past history of successes and failures in managing cormorants reveals that economic impact is greatest with aquaculture and least in sport fisheries. Research during the past 5 years suggests that some control methods like …

Nesting Populations Of Double-Crested Cormorants In The United States And Canada, Laura A. Tyson, Jerrold L. Belant, Francesca J. Cuthbert, D.V. (Chip) Weseloh

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

Double-crested cormorants (Phalacrocorax auritus) are receiving increasing attention in North America because of depredations at aquaculture facilities and alleged impacts on sport and commercial fisheries. We obtained recent (most since 1994) estimates for the number of nesting double-crested cormorants in the United States and Canada from published references and by conducting telephone interviews with State and Provincial biologists. Using published data, we also determined annual rates of change in the number of cormorants since about 1990. The estimated minimum number of nesting pairs (colonies) of double-crested cormorants was 372,000 (852). Most cormorants nested in the Interior region (68 …

Changes In The Status, Distribution, And Management Of Double-Crested Cormorants In Wisconsin, Summer W. Matteson, Paul W. Rasmussen, Kenneth L. Stromborg, Thomas I. Meier, Julie Van Stappen, Eric C. Nelson

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

We reviewed and summarized historical data and conducted population surveys from 1973 through 1997 to determine the breeding status and distribution of doublecrested cormorants (Phalacrocorax auritus) in Wisconsin. Breeding cormorants historically occupied large, isolated lakes and wetlands in northern Wisconsin, but there were no known nesting sites until 1919, when cormorants were reported nesting on Lake Wisconsin in south-central Wisconsin. From the 1920’s to the 1950’s, cormorants occupied 17 colony sites in 16 counties, though no more than 7 sites were occupied during any particular year. From the 1950’s to the early 1970’s, the number of cormorant nests …

Impact Of Double-Crested Cormorant Predation On The Yellow Perch Population In The Les Cheneaux Islands Of Michigan, Glenn Y. Belyea, Susan L. Maruca, James S. Diana, Philip J. Schneeberger, Steve J. Scott, Richard D. Clark Jr., James P. Ludwig, Cheryl L. Summer

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

The Michigan Department of Natural Resources, in conjunction with the University of Michigan and the U.S. Fish and Wildlife Service, initiated a research study to determine the impact of double-crested cormorants (Phalacrocorax auritus) on the yellow perch (Perca flavescens) population in the Les Cheneaux Islands area of northern Lake Huron. Aerial and nesting colony counts were conducted to monitor cormorant abundance. Creel census counts and tagging of 8,400 perch were used to study perch abundance. We collected 373 cormorants to study food habits via stomach-content analysis. We found that (1) cormorants fed heavily on yellow perch …

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 …

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

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

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 …

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

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.

Appendix 1: Authors' Affiliations

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

Authors' affiliations

Draft: Plan For The Management Of The Houtman Abrolhos Islands Fish Habitat Protection Area (Schedule 1), Abrolhos Islands Management Advisory Council, Fisheries Department Of Western Australia

Fisheries Management Papers

This document is a separate draft plan which has been prepared to meet the requirements of Section 117 of the Fish Resources Management Act 1994. It contains a description of the area; outlines the purposes for which the area is to be set aside; and lists the recommendations contained in Fisheries Management Paper No. 104, Management of the Houtman Abrolhos System, which relate to the management of the proposed Fish Habitat Protection Area.

Management Of The Houtman Abrolhos System, Abrolhos Islands Management Advisory Council, Fisheries Department Of Western Australia

Fisheries Management Papers

In November 1995 Cabinet resolved that the Minister for Fisheries would establish the Abrolhos Islands Management Advisory Committee (AIMAC) pursuant to Section 42 of the Fish Resources Management Act 1994. The role of AIMAC is to advise the Minister for Fisheries about the management of the Abrolhos Islands and the adjoining State Territorial Waters, as detailed in Section 2.2.3.1 of this report. The AIMAC has overseen the preparation of this report on behalf of the Minister for Fisheries. This draft report contains a brief description of the Abrolhos System and its special values. It also states goals and objectives for …

Index To Volume 65 Of The Nebraska Bird Review

Nebraska Bird Review

Index to Volume 65

Avocet, American 134

Alaska 53(2), 57

Albino 41

Alexander, George 35

Irene 35

Allen, Betty 36, 67

Alt, Jim 178

Anas Valisineria 58

Anhinga 7

Ani, Groove-billed 11

Anschutz, Steven Whooping Crane Sighting during March-May 132

.................

Zendeh, Soheil 126

Notes On The Nesting Biology Of Pygmy Nuthatches In Nebraska, Wayne Mollhoff

Nebraska Bird Review

Introduction

Pygmy Nuthatches (Sitta pygmaea) were considered to be no more than casual or rare winter visitors to the northwest part of Nebraska by previous investigators (Bruner et al. 1904; Swenk 1918; Haecker et al. 1945; Rapp et al. 1958, 1971). I. S. Trostler's earlier comment that the species was "a rare resident, breeds in Omaha" (Bruner 1896) was later felt to be in error, as evidenced by Bruner's later comment that it was, "A fall and winter visitor . . . not breeding in the state" (Bruner et al. 1904).

The first evidence of breeding was the …

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