Biological reference points for American lobster (Homarus americanus) populations: limits to exploitation and the precautionary approach

2004 ◽  
Vol 61 (8) ◽  
pp. 1392-1403 ◽  
Author(s):  
Michael J Fogarty ◽  
Louise Gendron
Keyword(s):  
United States ◽  
Egg Production ◽  
Large Scale ◽  
Abiotic Factors ◽  
Homarus Americanus ◽  
The United States ◽  
Reference Points ◽  
Population Increase ◽  
American Lobster ◽  
Precautionary Approach

Large-scale changes in American lobster (Homarus americanus) landings and abundance have been documented in both Canada and the United States over the last several decades. The spatial coherence of these changes suggests the importance of common environmental and fishery-related factors operating over broad areas in the western North Atlantic. Changes in both biotic and abiotic factors have been hypothesized to underlie the recent increases in lobster production. Area expansion of lobsters to previously unoccupied or low-density areas appears to be an important element of the population increase. Here, we review biological reference points applied to American lobster populations in the United States and Canada. Egg production per recruit models have been used to specify limit reference points (F10% in the United States) or target reference points (increasing egg production per recruit to twice its 1995 level in Canada). Surplus production and yield-per-recruit models have also been employed to provide qualitative management guidelines. We describe sources of uncertainty in the development of biological reference points for American lobster based on dynamic pool models in relation to the precautionary approach. Finally we consider auxiliary indicators and reference points with potential application to lobster stocks.

scholarly journals Developing and evaluating harvest control rules with different biological reference points for the American lobster (Homarus americanus) fishery in the Gulf of Maine

2011 ◽  
Vol 68 (7) ◽  
pp. 1511-1524 ◽  
Author(s):  
Yuying Zhang ◽  
Yong Chen ◽  
Carl Wilson
Keyword(s):  
Gulf Of Maine ◽  
Homarus Americanus ◽  
The United States ◽  
Reference Points ◽  
Systematic Evaluation ◽  
American Lobster ◽  
Natural Mortality ◽  
Control Rules ◽  
The Status ◽  
Harvest Control Rules

Abstract Zhang, Y., Chen, Y., and Wilson, C. 2011. Developing and evaluating harvest control rules with different biological reference points for the American lobster (Homarus americanus) fishery in the Gulf of Maine. – ICES Journal of Marine Science, 68: 1511–1524. The American lobster (Homarus americanus) supports one of the most valuable commercial fisheries in the United States. Controversy exists, however, in terms of the biological reference point (BRP) used in assessing lobster stock status, and there is no fully established or evaluated harvest control rule (HCR). A sex-specific, size-dependent operating model is developed to evaluate the performance of two HCRs, discrete and continuous, which adjust annual fishing mortality discretely and linearly, respectively, based on the status of the fishery. For each HCR, different BRPs are considered along with management duration, recruitment dynamics, and natural mortality. HCRs with a suitable set of BRPs can drive the fishery from an undesirable status to an optimal status. The continuous HCR tends to perform better than the discrete one. The Ftarget of 0.31 year−1 showed the best performance in the long term by balancing the needs of the fishing industry and conservation bodies. However, this was not the case in the short term. An Ntarget of 49.6 million would allow the American lobster to be maintained at its current stock level, with high recruitment and stable natural mortality. The study provides a framework for a systematic evaluation of management regulations for the American lobster.

Recruitment overfishing reference point for the American lobster, Homarus americanus

1997 ◽  
Vol 48 (8) ◽  
pp. 1029 ◽  
Author(s):  
G. P. Ennis ◽  
M. J. Fogarty
Keyword(s):  
Median Survival ◽  
Reference Point ◽  
Egg Production ◽  
Adult Population ◽  
Homarus Americanus ◽  
Reference Points ◽  
American Lobster ◽  
Survival Ratio ◽  
Low Level ◽  
Exploitation Rate

A 21-year series of annual estimates of egg production and recruitment in a Newfoundland lobster population indicates similar asymptotic relationships for recruitment to the fishery and to the adult population, both derived from legal stock estimates. Lines with slopes equal to the 90th-percentile and median survival ratios drawn through the origin of the egg production–adult recruitment scatterplot were examined as potential recruitment overfishing reference points for the Arnold’s Cove lobster stock. If the inverse of the estimated lifetime egg production per recruit (E/R) for a given exploitation rate exceeds the slope of the selected reference point, the risk of recruitment overfishing is high. For the Arnold’s Cove stock, the E/R level at a nominal 90% exploitation rate is estimated at 4.2% of the unfished population, compared with 2.5% for the overfishing reference point corresponding to the median survival ratio. Female lobsters at Arnold’s Cove mature at sizes below the minimum legal size, providing a buffer against high exploitation rates. Small, scattered refugia of large lobsters could also help to explain how heavily exploited populations of this species persist at such a low level of egg production.

Bobcat Population Status and Management in North America: Evidence of Large-Scale Population Increase

2010 ◽  
Vol 1 (2) ◽  
pp. 169-174 ◽  
Author(s):  
Nathan M. Roberts ◽  
Shawn M. Crimmins
Keyword(s):  
United States ◽  
North America ◽  
Wildlife Management ◽  
Large Scale ◽  
The United States ◽  
Lynx Rufus ◽  
Population Increase ◽  
Population Status ◽  
Current Population ◽  
Monitoring Protocols

Abstract Bobcat Lynx rufus populations are thought to be increasing in North America; however, little information exists on their current population status. In the United States, management and monitoring of bobcat populations is the responsibility of state wildlife management agencies. We surveyed state wildlife management agencies in each of the 48 contiguous states regarding the current population status, distribution, and monitoring protocols of bobcats within each respective jurisdiction. We also surveyed the governments of Mexico and Canada regarding bobcat population status within their jurisdictions. We received responses from 47 U.S. states, Mexico, and 7 Canadian provinces. Responses indicate that bobcats occur in each of the contiguous states except for Delaware. Populations were reported to be stable or increasing in 40 states, with 6 states unable to report population trends and only 1 state (Florida) reporting decreases in bobcat populations. Of the 47 states in which bobcats occur, 41 employ some form of population monitoring. Population density estimates were available for 2,011,518 km2 (33.6%) of the estimated bobcat range in the United States, with population estimates between 1,419,333 and 2,638,738 individuals for this portion of their range and an estimated 2,352,276 to 3,571,681 individuals for the entire United States. These results indicate that bobcat populations have increased throughout the majority of their range in North America since the late 1990s and that populations within the United States are much higher than previously suggested.

On the Viability of Small Countries

1975 ◽  
Vol 17 (3) ◽  
pp. 259-280 ◽  
Author(s):  
John Kirby
Keyword(s):  
United States ◽  
Latin America ◽  
Large Scale ◽  
Rio Grande ◽  
The United States ◽  
Small Population ◽  
Population Increase ◽  
Rio Grande Do Sul ◽  
Self Interest ◽  
Small Countries

The argument advanced by Bordaberry … by the United States and Brazilian embassies, and by the cattle and meat interests, is that Uruguay does not have a viable independent economy. It is smaller, on most terms of reference, than the southernmost state of Brazil–Rio Grande do Sul–and would, they say, be far better off if its economy were “rationalized” and integrated with the more “modern” large-scale Brazilian economy.Latin America, Vol. VIII, No. 31, August 3 ,1973Leaving aside the obvious self-interest of the various proponents (although one is tempted to speculate whether President Bordaberry argues on behalf of his country or his own ranching interests), their conclusion follows logically on much of the analysis which has focused on the causes of Uruguay's stagnation. Since the mid-1950s, the growth of the economy has barely kept pace with the small population increase of 1.2 percent per annum.

scholarly journals River Otter Status, Management, and Distribution in the United States: Evidence of Large-Scale Population Increase and Range Expansion

2020 ◽  
Vol 11 (1) ◽  
pp. 279-286 ◽  
Author(s):  
Nathan M. Roberts ◽  
Matthew J. Lovallo ◽  
Shawn M. Crimmins
Keyword(s):  
United States ◽  
Geographic Distribution ◽  
Large Scale ◽  
The United States ◽  
Lontra Canadensis ◽  
Population Increase ◽  
River Otter ◽  
River Otters ◽  
Scale Population ◽  
Management Approaches

Abstract River otter Lontra canadensis populations in the United States have expanded during the past 50 y as a result of improvements in habitat quality and effective management programs implemented by state and federal agencies and native tribes. Periodic assessments of river otter status, population trends, and geographic distribution are needed to detect changes in populations, assess management approaches, and to identify and prioritize conservation efforts. We surveyed state wildlife agency experts to assess the current population and regulatory status of river otters in their jurisdictions. River otters were legally harvested in 40 states as of 2016. Twenty-two states reported increasing populations while 25 reported stable populations. Most states used multiple methods to monitor river otter populations including harvest-based surveys, presence–absence surveys, and empirically derived population model predictions; harvest-based surveys were the most commonly used monitoring approach. As populations have expanded, river otter reintroduction efforts have become less frequent; two additional states had conducted reintroductions since 1998 and only one state had conducted a reintroduction since 2010. We estimated that river otter distribution increased by 10.2% in the continental United States and by 13.7% in the contiguous United States during an 18-y period. Although populations may continue to increase numerically, river otters may be approaching their potential maximum geographic distribution in the United States.

Quality Control of Data in a Large-Scale Cancer Register Program

1966 ◽  
Vol 05 (02) ◽  
pp. 67-74 ◽  
Author(s):  
W. I. Lourie ◽  
W. Haenszeland
Keyword(s):  
United States ◽  
Quality Control ◽  
Cancer Patients ◽  
Large Scale ◽  
The United States ◽  
Newly Diagnosed ◽  
Related Data ◽  
Cancer Register ◽  
Independent Review ◽  
End Results

Quality control of data collected in the United States by the Cancer End Results Program utilizing punchcards prepared by participating registries in accordance with a Uniform Punchcard Code is discussed. Existing arrangements decentralize responsibility for editing and related data processing to the local registries with centralization of tabulating and statistical services in the End Results Section, National Cancer Institute. The most recent deck of punchcards represented over 600,000 cancer patients; approximately 50,000 newly diagnosed cases are added annually.Mechanical editing and inspection of punchcards and field audits are the principal tools for quality control. Mechanical editing of the punchcards includes testing for blank entries and detection of in-admissable or inconsistent codes. Highly improbable codes are subjected to special scrutiny. Field audits include the drawing of a 1-10 percent random sample of punchcards submitted by a registry; the charts are .then reabstracted and recoded by a NCI staff member and differences between the punchcard and the results of independent review are noted.

Utopias of One

2019 ◽  
Author(s):  
Joshua Kotin
Keyword(s):  
United States ◽  
Soviet Union ◽  
World War I ◽  
Large Scale ◽  
Jim Crow ◽  
Personal Autonomy ◽  
The United States ◽  
Soviet Period ◽  
Original Research ◽  
The Soviet Union

This book is a new account of utopian writing. It examines how eight writers—Henry David Thoreau, W. E. B. Du Bois, Osip and Nadezhda Mandel'shtam, Anna Akhmatova, Wallace Stevens, Ezra Pound, and J. H. Prynne—construct utopias of one within and against modernity's two large-scale attempts to harmonize individual and collective interests: liberalism and communism. The book begins in the United States between the buildup to the Civil War and the end of Jim Crow; continues in the Soviet Union between Stalinism and the late Soviet period; and concludes in England and the United States between World War I and the end of the Cold War. In this way it captures how writers from disparate geopolitical contexts resist state and normative power to construct perfect worlds—for themselves alone. The book contributes to debates about literature and politics, presenting innovative arguments about aesthetic difficulty, personal autonomy, and complicity and dissent. It models a new approach to transnational and comparative scholarship, combining original research in English and Russian to illuminate more than a century and a half of literary and political history.

Situational Breakdowns

2019 ◽  
Author(s):  
Anne Nassauer
Keyword(s):  
United States ◽  
Large Scale ◽  
Contextual Factors ◽  
The United States ◽  
Social Outcomes ◽  
Dynamic Processes ◽  
Collective Decisions ◽  
Different Types ◽  
The Impact

This book provides an account of how and why routine interactions break down and how such situational breakdowns lead to protest violence and other types of surprising social outcomes. It takes a close-up look at the dynamic processes of how situations unfold and compares their role to that of motivations, strategies, and other contextual factors. The book discusses factors that can draw us into violent situations and describes how and why we make uncommon individual and collective decisions. Covering different types of surprise outcomes from protest marches and uprisings turning violent to robbers failing to rob a store at gunpoint, it shows how unfolding situations can override our motivations and strategies and how emotions and culture, as well as rational thinking, still play a part in these events. The first chapters study protest violence in Germany and the United States from 1960 until 2010, taking a detailed look at what happens between the start of a protest and the eruption of violence or its peaceful conclusion. They compare the impact of such dynamics to the role of police strategies and culture, protesters’ claims and violent motivations, the black bloc and agents provocateurs. The analysis shows how violence is triggered, what determines its intensity, and which measures can avoid its outbreak. The book explores whether we find similar situational patterns leading to surprising outcomes in other types of small- and large-scale events: uprisings turning violent, such as Ferguson in 2014 and Baltimore in 2015, and failed armed store robberies.

Ban Ki-moon, 2007–2016

2018 ◽  
Author(s):  
Richard Gowan
Keyword(s):  
United States ◽  
Decision Making ◽  
Security Council ◽  
Large Scale ◽  
Central African Republic ◽  
The United States ◽  
Cautious Approach ◽  
Peacekeeping Operations ◽  
Council Decision ◽  
The Face

During Ban Ki-moon’s tenure, the Security Council was shaken by P5 divisions over Kosovo, Georgia, Libya, Syria, and Ukraine. Yet it also continued to mandate and sustain large-scale peacekeeping operations in Africa, placing major burdens on the UN Secretariat. The chapter will argue that Ban initially took a cautious approach to controversies with the Council, and earned a reputation for excessive passivity in the face of crisis and deference to the United States. The second half of the chapter suggests that Ban shifted to a more activist pressure as his tenure went on, pressing the Council to act in cases including Côte d’Ivoire, Libya, and Syria. The chapter will argue that Ban had only a marginal impact on Council decision-making, even though he made a creditable effort to speak truth to power over cases such as the Central African Republic (CAR), challenging Council members to live up to their responsibilities.

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