The Effect of a Change in the Size at First Capture in the Rhode Island Inshore Lobster Fishery: A Bioeconomic Analysis

1983 ◽  
Vol 12 (2) ◽  
pp. 121-121
Author(s):  
Edward J. Richardson
Keyword(s):  
Rhode Island ◽  
Homarus Americanus ◽  
Minimum Size ◽  
Full Time ◽  
Fleet Size ◽  
Regional Market ◽  
Length Increase ◽  
Short Run ◽  
Lobster Fishery ◽  
Social Surplus

At this time minimum size limit regulations are the primary tool used to manage Rhode Island's American lobster (Homarus americanus) resource. One shortcoming of this policy is its lack of foundation in bioeconomic analysis. To encourage the incorporation of bioeconomic considerations into the management strategy used on this valuable resource, a fishery simulator (Gates 1974) was modified and employed to analyze the effects of changing the size at first capture in Rhode Island's inshore lobster fishery.A cost and earnings survey of Rhode Island's commercial lobster license holders was conducted to provide the economic data required to simulate the fishery. This survey uncovered information characterizing the exploitation of the resource. For example, the survey estimated inshore catch of 2.1 million pounds indicates that three quarters of the inshore catch may go unrecorded. The survey also revealed that full-time commercial harvesters are outnumbered by part-time personnel by a factor of seven, but still land over 90% of Rhode Island's lobster catch.The simulation results also proved quite informative. They suggest that an increase in Rhode Island's minimum size at first capture, if promulgated alone, will not confer increased benefits to society or fishermen. In fact, if a reasonable rate of discount is employed, the analysis indicates the measure will decrease the present value of social surplus generated by Rhode Island's inshore lobster fishery. Averaging over the range of results obtained, an 0.8 mm carapace length increase will reduce annualized benefits by 7%. Alternative larger increases of 1.6 mm and 9.5 mm (3.5 inch minimum) are estimated to bring about 10% and 38% reductions in the annualized value of social surplus that the inshore fishery can be expected to generate. These results are due in part to the substantial short run decreases in catch that the increased minimum sizes generate, and in part because it is assumed that the increased minimum size will govern Rhode Island's landings only.The immediate short run decreases in benefits that accompany the minimum size increases were found to fall primarily on the harvesters of the resource. Averaging over the discount rates employed, 87% of the short run reductions in social surplus subtracted from producer revenues. All results assume that stock recruitment is independent of stock size, that stock reproductive security is not at issue, and that lobster prices are determined in a regional market for live lobsters.Additional simulations were performed to compare the social surplus in the open access fishery with that which might be obtained should access to the fishery be restricted. Also, social surpluses were obtained for the fishery under the assumption that an increased size at first capture results in increased recruitment. These simulations point to the general result that increased harvest selectivity will maximize the sustainable fleet size while concurrently reducing the annual social surplus generated by the fishery.

Delayed Recruitment Models and Their Application to the American Lobster (Homarus americanus) Fishery

1976 ◽  
Vol 33 (8) ◽  
pp. 1779-1787 ◽  
Author(s):  
Guy D. Marchesseault ◽  
Saul B. Saila ◽  
William J. Palm
Keyword(s):  
Rhode Island ◽  
Homarus Americanus ◽  
Management Decision ◽  
American Lobster ◽  
Stock Level ◽  
Analytical Properties ◽  
Management Decision Making ◽  
Subsequent Behavior ◽  
Lobster Fishery ◽  
Recruitment Model

A delayed recruitment model intended for use in developing dynamic strategies for fisheries management is proposed. The conceptual and analytical properties of the model are elaborated and compared with those of the instantaneous model of Schaefer and the delayed recruitment model recently suggested by Walter. Of the three models discussed, the delayed recruitment model proposed herein constitutes the more biologically meaningful tool for use in management decision making with fisheries characterized by a multiple year delay between spawning and recruitment. The proposed delay and Schaefer models are fitted to catch and effort data from the Rhode Island inshore pot lobster fishery, and the generated coefficients are examined with respect to their interpretation and relative importance. Values of optimum equilibrium catch and effort are calculated for the proposed delay and Schaefer models, and we show that the delay model’s estimates of these management indices are more conservative than those derived from Schaefer’s model. The proposed delay and Schaefer models are compared in a dynamic analysis of the fishery, in which perturbations in the stock level and fluctuations in the applied effort are simulated to predict the subsequent behavior of the stock.

scholarly journals American lobster nurseries of southern New England receding in the face of climate change

2015 ◽  
Vol 72 (suppl_1) ◽  
pp. i69-i78 ◽  
Author(s):  
Richard A. Wahle ◽  
Lanny Dellinger ◽  
Scott Olszewski ◽  
Phoebe Jekielek
Keyword(s):  
New England ◽  
Rhode Island ◽  
Size Composition ◽  
Homarus Americanus ◽  
Warming Trend ◽  
Shore Crab ◽  
American Lobster ◽  
Southern New England ◽  
Study Sites ◽  
Outer Coast

Abstract Historically, southern New England has supported one of the most productive American lobster (Homarus americanus) fisheries of the northeast United States. Recently, the region has seen dramatic declines in lobster populations coincident with a trend of increasingly stressful summer warmth and shell disease. We report significant declines in the abundance, distribution, and size composition of juvenile lobsters that have accompanied the warming trend in Narragansett Bay, Rhode Island, since the first comprehensive survey of lobster nurseries conducted there in 1990. We used diver-based visual surveys and suction sampling in 1990, 2011, and 2012, supplemented by post-larval collectors in 2011 and 2012. In 1990, lobster nurseries extended from the outer coast into the mid-sections of the bay, but by 2011 and 2012 they were largely restricted to the outer coast and deeper water at the mouth of the bay. Among five new study sites selected by the lobster fishing industry for the 2011 and 2012 surveys, the deepest site on the outer coast (15–17 m depth) harboured some of the highest lobster densities in the survey. Separate fixed site hydrographic monitoring at 13 locations in the bay by the Rhode Island Division of Fish and Wildlife recorded an approximately 2.0°C increase in summer surface temperatures over the period, with 2012 being the warmest on record. Additional monitoring of bottom temperatures, dissolved oxygen and pH at our sampling sites in 2011 and 2012 indicated conditions falling below physiological optima for lobsters during summer. The invasion of the Asian shore crab, Hemigrapsus sanguineus, since the 1990s may also be contributing to declines of juvenile lobster shallow zones (<5 m) in this region. Because lobster populations appear increasingly restricted to deeper and outer coastal waters of southern New England, further monitoring of settlement and nursery habitat in deep water is warranted.

Neurohormonal alteration of integrative properties of the cardiac ganglion of the lobster Homarus americanus

1975 ◽  
Vol 63 (1) ◽  
pp. 33-52
Author(s):  
I. M. Cooke ◽  
D. K. Hartline
Keyword(s):  
Impulse Activity ◽  
Homarus Americanus ◽  
Firing Frequency ◽  
Small Cell ◽  
Small Cells ◽  
Cardiac Ganglion ◽  
Cardiac Ganglia ◽  
Length Increase ◽  
Proximal Site ◽  
Intermediate Value

The spontaneous burst discharges of isolated lobster (Homarus americanus) cardiac ganglia were recorded with a spaced array of electrodes. Small regions (less than 1 mm) of the ganglion were exposed to the cardioexcitor neurohormone in extracts of pericardial organs (XPO) or to 10(−5) M 5-hydroxytryptamine (5HT). All axons were excited (increased mean firing frequency, f) by both substances, but only by applications in the region between the soma (but excluding it) and proximal site of impulse initiation. Units not so exposed changed their f relatively little despite f increases of as much as threefold in exposed units and changes in burst rate and overall length. Regularity and grouping of all impulse activity into bursts was never disturbed. 5HT increases burst rate at any point of application. The increases are larger if small cells are affected than if only large cells are exposed. Burst length decreases except when the pacemaker is affected. In contrast, XPO affects neither burst rate or length unless small cells are affected. Length is increased if non-pacemaker small cells are affected; both rate and length increase if the pacemaker is affected. The pacemaker usually exhibits an f of intermediate value. Rate changes are not simply related to its f. A small cell can “burst” in the absence of impulses from any other cells. XPO may enhance endogenous “driver potentials,” while 5HT may excite by depolarizing at limited sites.

scholarly journals Mason biodiesel: A family℉s new venture in a new industry

2009 ◽  
Vol 12 (2) ◽  
pp. 63-70
Author(s):  
Matthew Eriksen ◽  
George H. Tompson
Keyword(s):  
United States ◽  
Rhode Island ◽  
The United States ◽  
New Venture ◽  
Full Time ◽  
Bank Debt ◽  
Start Up ◽  
Personal Savings ◽  
New Industry ◽  
Biodiesel Industry

This case describes a real family that has been running a labor-intensive business since 1992. The father, Phil Mason, runs the business with the help of his wife and two of his sons in southwestern Rhode Island. The business is a franchisee of ServiceMaster Clean. In 2006, the franchise employed 20 full-time employees and was the 50th largest ServiceMaster Clean franchise among the approximately 1,200 franchises located in the United States. Annual revenue is approximately $2.5 million. In late 2005, one of Phil℉s sons began researching the biodiesel industry. As he was growing weary of the labor-intensive nature of his franchise business, Phil fully researched the industry himself. By the middle of 2006, Phil was convinced that he could profitably manufacture biodiesel in his spare warehouse space. In July 2006, he formed Mason Biodiesel, LLC and financed the $1.5 million start-up costs through a combination of personal savings and bank debt.

An Analysis of Temperature Effects on the Inshore Lobster Fishery

1972 ◽  
Vol 29 (8) ◽  
pp. 1221-1225 ◽  
Author(s):  
J. M. Flowers ◽  
S. B. Saila
Keyword(s):  
World War Ii ◽  
Homarus Americanus ◽  
The United States ◽  
Fishing Effort ◽  
Yield Prediction ◽  
World War ◽  
Independent Variables ◽  
The Past ◽  
Summer Temperatures ◽  
Lobster Fishery

In the past, water temperature has been utilized in combination with some measure of fishing effort in the development of economic estimator or predictor equations for the yield of the lobster Homarus americanus. The hypothesis that the inshore lobster fishery in the United States has been overfished since the end of World War II to the point where increases in fishing effort since that time have had only minor effects on the yields was examined. It was shown that suitable yield prediction equations could be developed using only lagged and present temperatures as the independent variables. Comparisons were made of equations developed for the Maine fishery and sections of the Canadian fishery. Further analyses were done comparing equations developed using winter vs. summer temperatures and surface vs. bottom temperatures.

Perceptions of opioid misuse and chronic pain: A qualitative assessment of Rhode Island commercial fishing captains

2019 ◽  
Vol 15 (2) ◽  
pp. 129-135 ◽  
Author(s):  
Travis Brown, BS ◽  
Paul George, MD, MHPE
Keyword(s):  
Chronic Pain ◽  
Rhode Island ◽  
Healthcare Access ◽  
Qualitative Assessment ◽  
Commercial Fishing ◽  
Full Time ◽  
Opioid Misuse ◽  
Work Related ◽  
Opiate Use ◽  
Recurrent Patterns

Objectives: To better understand how the contextual circumstances and lifestyle of commercial fishermen influence their access to healthcare and potentially contribute to the use and misuse of opioids.Methods: The authors conducted in-person, semistructured interviews with 15 full-time fishing captains in Rhode Island between the months of May and July of 2017.Results: The authors identified five major themes: Recurrent patterns of addiction and opiate use among crewmembers; chronic pain and injury as common constructs of life in the fishing industry; insufficient pain management resources; practical barriers to obtaining primary healthcare; and perceived lack of support from state government.Conclusions: Rhode Island commercial fishing captains perceived opioid misuse among crewmembers, work-related chronic pain, and inadequate healthcare access as barriers to sustainability of their industry.

Modeling shell disease in American lobster (Homarus americanus) as individual-based health trajectories

2014 ◽  
Vol 71 (6) ◽  
pp. 808-813 ◽  
Author(s):  
Michael F. Tlusty ◽  
Anita Kim ◽  
Kathleen M. Castro
Keyword(s):  
Conceptual Understanding ◽  
Gulf Of Maine ◽  
Homarus Americanus ◽  
Molt Cycle ◽  
Health Trajectories ◽  
Human Parasite ◽  
Before And After ◽  
Shell Disease ◽  
Lobster Fishery ◽  
Important Disease

The emergence of epizootic shell disease in American lobsters (Homarus americanus) has presented many new challenges to understanding the interface between disease and the management of the lobster fishery. While a variety of the potentially causative and correlative factors for shell disease have been explored, a clear etiological agent remains elusive. The recency of this disease and the lack of identifiable causal agents have hindered the development of conceptual models that can yield testable predictions. Here, a model originally developed for human–parasite interactions was applied to lobster shell disease as a means to unify the broad experimental and field observations. The model is a graphical means to understand the onset and severity of shell disease and is a function of the length of the molt cycle and the rate of the decrease of health both before and after lesion formation as a function of bacterial abundance and pathogenicity. The model also accounts for shell hardening and passive and active portals of entry for the bacteria. The timing for a conceptual understanding of the epidemiology of shell disease is critical because its prevalence is increasing in key fishing areas. Ideally, such a model will help researchers create hypothesis-driven predictive experiments from which we can further our understanding of an important disease to a critical member of the Gulf of Maine ecosystem.

Seasonal Distributions of Bottom Fishes in the Narragansett Bay Area: Seven-Year Variations in the Abundance of Winter Flounder (Pseudopleuronectes americanus)

1974 ◽  
Vol 31 (6) ◽  
pp. 1057-1066 ◽  
Author(s):  
H. Perry Jeffries ◽  
William C. Johnson
Keyword(s):  
Rhode Island ◽  
Homarus Americanus ◽  
Narragansett Bay ◽  
Winter Flounder ◽  
Pseudopleuronectes Americanus ◽  
Commercial Catch ◽  
Average Temperature ◽  
Climatic Trends ◽  
Bay Area ◽  
Time Required

Weekly bottom trawl samples taken in Narragansett Bay and Rhode Island Sound from January 1966 through December 1972 showed patterns of occurrence within a diverse assemblage of migratory and resident stocks. Relative abundance of winter flounder (Pseudopleuronectes americanus), the commonest species in the Bay, appeared to be associated with climatic trends but not with fishing pressure. Catch decreased 78% from 1968 to 1972. Average temperature during 30-mo periods, the time required for flounder to reach catchable size, explained 76% of variation in abundance through the study. Annual abundance in the Bay is also reflected 2–3 yr later in the commercial catch. A speculative explanation for control of the population in an estuarine nursery is developed, based on subtle climatic trends whose effects have been magnified many times over by competitive processes among migratory populations.The sand flounder (Scophthalmus aquosus), second in general abundance, varied far less than the winter flounder. Catches of the lobster (Homarus americanus) and winter flounder were directly related, both on a monthly as well as yearly basis. The remaining species of numerical importance appeared to avoid peak abundances of one another in the Bay and Sound; rarely did seasonal maxima of two or more species occur during the same month.

A simulation study to evaluate impacts of uncertainty on the assessment of American lobster fishery in the Gulf of Maine

2002 ◽  
Vol 59 (8) ◽  
pp. 1394-1403 ◽  
Author(s):  
Yong Chen ◽  
Carl Wilson
Keyword(s):  
Confidence Level ◽  
Gulf Of Maine ◽  
Homarus Americanus ◽  
American Lobster ◽  
Large Uncertainty ◽  
Decision Confidence ◽  
The Status ◽  
Status Assessment ◽  
Lobster Fishery ◽  
Risk Managers

The status of the American lobster (Homarus americanus) in the Gulf of Maine (GOM) has been assessed for the last two decades by comparing an estimated current fishing mortality rate for females (Fcur) with a deterministically estimated biological reference point, F10%. The most recent assessment determined that GOM had exceeded the F10% for every year calculated, although in this time landings and abundance have doubled. The current policy does not consider uncertainty in the assessment. This study evaluates the impacts of uncertainty in F10% and Fcur on the status assessment of lobster fishery. Using a Monte Carlo simulation approach, we found that the status assessment would be influenced by uncertainties in estimating F10% and Fcur, and by the choice of decision confidence level reflecting the level of risk managers would like to take. A large uncertainty in Fcur and F10% and a high decision confidence level reduce the likelihood of defining the stock as overfished, and vice versa. Our results suggest that the probability of lobster overfishing may be less than previously thought, and that uncertainty in Fcur and F10% should be quantified and considered in determining the status of the GOM lobster stock.

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