Coupling ecology and economy: modeling optimal release scenarios for summer flounder (Paralichthys dentatus) stock enhancement

Increasing interest in the use of stock enhancement as a management tool necessitates a better understanding of the relative costs and benefits of alternative release strategies. We present a relatively simple model coupling ecology and economic costs to make inferences about optimal release scenarios for summer flounder (Paralichthys dentatus), a subject of stock enhancement interest in North Carolina. The model, parameterized from mark-recapture experiments, predicts optimal release scenarios from both survival and economic standpoints for varyious dates-of-release, sizes-at-release, and numbers of fish released. Although most stock enhancement efforts involve the release of relatively small fish, the model suggests that optimal results (maximum survival and minimum costs) will be obtained when relatively large fish (75–80 mm total length) are released early in the nursery season (April). We investigated the sensitivity of model predictions to violations of the assumption of density-independent mortality by including density-mortality relationships based on weak and strong type-2 and type-3 predator functional responses (resulting in depensatory mortality at elevated densities). Depending on postrelease density, density-mortality relationships included in the model considerably affect predicted postrelease survival and economic costs associated with enhancement efforts, but do not alter the release scenario (i.e. combination of release variables) that produces optimal results. Predicted (from model output) declines in flounder over time most closely match declines observed in replicate field sites when mortality in the model is density-independent or governed by a weak type-3 functional response. The model provides an example of a relatively easy-to-develop predictive tool with which to make inferences about the ecological and economic potential of stock enhancement of summer flounder and provides a template for model creation for additional species that are subjects of stock enhancement interest, but for which limited empirical data exist

Rethinking Supply Chains as Neighborhoods

This paper explores the implication of a neighborhood model for interfirm interactions that explicitly tries to create an equality matching relationship among firms in an industry. The aim is to examine what would happen if these firms worked to gain trust with each other with an eye toward maximizing the value of the collaboration across projects rather than just maximizing revenues in individual projects. A review of extant literature and an analysis of in-depth interviews yielded three actionable strategies that support the creation of a sustainable neighborhood in the construction industry: 1) Hub Strategy, 2) Trust Exercise Strategy, and 3) Sustainable Neighborhood Strategy. As envisioned in this study, the hub is a concentrated, inter-organizational structure for supply chain participants in large, complex projects. Importantly, hub members engage in a variety of technical activities that infuse ongoing and future projects with innovation, scope optimization, and operational efficiencies. Additionally, other activities within the hub are designed to purposefully allow participants to develop trust through collaboration before or outside of their primary contractual engagements. At present, this model has been examined for construction megaprojects, but the general neighborhood concept could be applied to many different industries and settings including manufacturing supply chains and collaborations among communities engaging in economic development. Future work will explore whether mechanisms like the hub and trust exercises can be applied in these other settings as well.IC2 Institut

Resources for Texas Sexual Assault Survivors: Inventory and Survey Findings on Services, Gaps, and Accessibility

Texas is a leader among states on the issue of sexual assault, and has promoted and funded the study of sexual violence as well as created the Sexual Assault Survivors’ Task Force (SASTF) through the Office of the Texas Governor (OOG). Sexual assault is clearly established as a public health problem affecting 6.3 million women and men in the state, or 33.2% of adult Texans over their lifetime.1 This statistic comes from thorough research by the Institute on Domestic Violence & Sexual Assault (IDVSA) at The University of Texas at Austin on the prevalence and impact of sexual assault on Texans, service providers, and the social and economic system at large. The bipartisan passage of HB 1590 (86R) B signifies a continued commitment by Texas lawmakers to serve sexual assault survivors. Lawmakers and Texans alike acknowledge the seriousness of sexual assault crimes. With the research findings derived from this project, survivors and their families, professionals supporting survivors, and lawmakers can better see the landscape of resources, service provision gaps, and unmet needs across our state. The specific project aims were to: • Inventory the sexual assault services available in Texas. • Assess sexual assault survivors’ needs by region for the 11 Texas regions. • Develop a sexual assault services resource inventory. IDVSA accomplished those aims by: • Developing and implementing a statewide survey to a broad and diverse set of providers who serve survivors of sexual violence. • Conducting a collaborative analysis of the survey findings with a specific focus on service availability and service gaps, and presenting those in this report to the OOG. • Developing an HB 1590 Inventory List of the resources available to survivors across the state and delivering it to the OOG to inform the creation of a comprehensive statewide service directory in the futureInstitute on Domestic Violence and Sexual Assault (IDVSA

Marine nurseries and effective juvenile habitats: concepts and applications

Much recent attention has been focused on juvenile fish and invertebrate habitat use, particularly defining and identifying marine nurseries. The most significant advancement in this area has been the development of a standardized framework for assessing the relative importance of juvenile habitats and classifying the most productive as nurseries. Within this framework, a marine nursery is defined as a juvenile habitat for a particular species that contributes a greater than average number of individuals to the adult population on a per-unit-area basis, as compared to other habitats used by juveniles. While the nursery definition and framework provides a powerful approach to identifying habitats for conservation and restoration efforts, it can omit habitats that have a small per-unit-area contribution to adult populations, but may be essential for sustaining adult populations. Here we build on the nursery concept by developing a framework for evaluating juvenile habitats based on their overall contribution to adult populations, and introduce the concept of Effective Juvenile Habitat (EJH) to refer to habitats that make a greater than average overall contribution to adult populations.Craig P. Dahlgren, G. Todd Kellison, Aaron J. Adams, Bronwyn M. Gillanders, Matthew S. Kendall, Craig A. Layman, Janet A. Ley, Ivan Nagelkerken, Joseph E. Seraf

Marine nurseries and effective juvenile habitats

Craig A. Layman, Craig P. Dahlgren, G. Todd Kellison, Aaron J. Adams, Bronwyn M. Gillanders, Matthew S. Kendall, Janet A. Ley, Ivan Nagelkerken and Joseph E. Seraf

Political activity in escalation of commitment: Sport facility funding and government decision making in the United States

In the United States, the decision to commit extensive public resources to sport facilities is a contentious topic of debate. Elected officials often commit substantial public resources to sport facility projects amidst contrary empirical evidence and mixed residential approval. This behavior not only implicates the presence of political activity to advance a course of action, but also suggests an escalation of commitment (EoC), the subject of this study. The authors implemented a collective case study approach to examine three municipalities with long-standing histories of subsidizing professional sport facilities. Data collected from influential elected officials and public leaders (N = 13) as well as documents and records revealed (a) political action to be essential in EoC with decisions involving multiple stakeholder groups; (b) the influence and interaction of political action within each EoC determinant; (c) the substantial role of support, resources, power, and influence in efforts to increase and prevent commitment to a failing course of action; and (d) noticeable spillover effects from use of political activity in EoC

A comparative analysis of infractions in Texas alcohol establishments and adult entertainment clubs

A crucial yet disputed element in the attempt to regulate sexually oriented businesses has been the negative secondary effects these firms have on nearby businesses and residential communities. This paper addresses a new dimension of the negative effects from such businesses by examining data on administrative and criminal infractions inside a large number of sexually oriented businesses and a comparable group of alcohol establishments. We compare administrative and criminal violations data from the Texas Alcohol Beverage Commission for all adult entertainment clubs (AECs) serving alcohol against a randomly selected sample of bars in the State of Texas. We find that there are important differences between the clubs and bars in 10 of the 23 t-test comparisons. What is more, even though alcohol-related infractions are the most common type of infraction for both AECs and for bars, the number of sex- and drug-related offenses was consistently more prevalent for sexually oriented businesses than for bars. In contrast, the bars have much higher numbers of criminal violations, primarily because of the higher incidence of infractions involving minors. This paper contributes to the literature on negative primary and secondary effects of sexually oriented businesses.clos

Potential Sources of Red Snapper (\u3ci\u3eLutjanus campechanus\u3c/i\u3e) Recruits Estimated With Markov Chain Monte Carlo Analysis of Otolith Chemical Signatures

Otolith chemical signatures were used to estimate the number of likely nursery sources that contributed recruits to a suite of red snapper (Lutjanus campechanus) year-classes sampled in 2012 in US Atlantic Ocean waters from southern Florida (28°N) to North Carolina (34°N). Otoliths from subadult and adult fish (n = 139; ages 2–5 years) were cored and their chemical constituents analysed for δ13C, δ18O, as well as the elemental ratios of Ba : Ca, Mg : Ca, Mn : Ca and Sr : Ca. Results from multiple linear regression analyses indicated that there was significant latitudinal variation for δ13C, Ba : Ca, Mg : Ca and Mn : Ca. Therefore, these variables were used to parameterise Markov Chain Monte Carlo (MCMC) models computed to estimate the most likely number of nursery sources to each age class. Results from MCMC models indicated that between two and seven nursery sources were equally plausible among the four age classes examined, but the likely number of nursery sources declined for fish aged 4 and 5 years because of apparent mixing between more northern and more southern signatures. Overall, there is evidence to reject the null hypothesis that a single nursery source contributed recruits among the age classes examined, but increased sample size from a broader geographic range may be required to refine estimates of the likely number of nursery sources

Functional response of sport divers to lobsters with application to fisheries management. Ecological Applications 18:258–272

Abstract. Fishery managers must understand the dynamics of fishers and their prey to successfully predict the outcome of management actions. We measured the impact of a twoday exclusively recreational fishery on Caribbean spiny lobster in the Florida Keys, USA, over large spatial scales (.100 km) and multiple years and used a theoretical, predator-prey functional response approach to identify whether or not sport diver catch rates were densityindependent (type I) or density-dependent (type II or III functional response), and if catch rates were saturated (i.e., reached an asymptote) at relatively high lobster densities. We then describe how this predator-prey framework can be applied to fisheries management for spiny lobster and other species. In the lower Keys, divers exhibited a type-I functional response, whereby they removed a constant and relatively high proportion of lobsters (0.74-0.84) across all pre-fishing-season lobster densities. Diver fishing effort increased in a linear manner with lobster prey densities, as would be expected with a type-I functional response, and was an order of magnitude lower in the upper Keys than lower Keys. There were numerous instances in the upper Keys where the density of lobsters actually increased from before to after the fishing season, suggesting some type of ''spill-in effect'' from surrounding diver-disturbed areas. With the exception of isolated reefs in the upper Keys, the proportion of lobsters removed by divers was density independent (type-I functional response) and never reached saturation at natural lobster densities. Thus, recreational divers have a relatively simple predatory response to spiny lobster, whereby catch rates increase linearly with lobster density such that catch is a reliable indicator of abundance. Although diver predation is extremely high (;80%), diver predation pressure is not expected to increase proportionally with a decline in lobster density (i.e., a depensatory response), which could exacerbate local extinction. Furthermore, management actions that reduce diver effort should have a concomitant and desired reduction in catch. The recreational diver-lobster predator-prey construct in this study provides a useful predictive framework to apply to both recreational and commercial fisheries, and on which to build as management actions are implemented