scholarly journals Managing a complex population structure: exploring the importance of information from fisheries-independent sources

2014 ◽  
Vol 72 (2) ◽  
pp. 528-542 ◽  
Author(s):  
N. T. Hintzen ◽  
B. Roel ◽  
D. Benden ◽  
M. Clarke ◽  
A. Egan ◽  
...  
Keyword(s):  
Population Structure ◽  
Simulation Modelling ◽  
Reference Points ◽  
Success Rates ◽  
Classification Problems ◽  
Population Unit ◽  
Catch Data ◽  
Resource Managers ◽  
Complex Population ◽  
Natural Resource Managers

Abstract Natural resource managers aim to manage fish stocks at sustainable levels. Often, management of these stocks is based on the results of analytical stock assessments. Accurate catch data, which can be attributed to a specific population unit and reflects the population structure, are needed for these approaches. Often though, the quality of the catch data is compromised when dealing with a complex population structure where fish of different population units mix in a fishery. The herring population units west of the British Isles are prone to mixing. Here, the inability to perfectly allocate the fish caught to the population unit they originate from, due to classification problems, poses problems for management. These mixing proportions are often unknown; therefore, we use simulation modelling combined with management strategy evaluation to evaluate the role fisheries-independent surveys can play in an assessment to provide unbiased results, irrespective of population unit mixing and classification success. We show that failure to account for mixing is one of the major drivers of biased estimates of population abundance, affecting biomass reference points and MSY targets. When mixing of population units occurs, the role a survey can play to provide unbiased assessment results is limited. Either different assessment models should be employed or stock status should be considered from the survey data alone. In addition, correctly classifying the origin of fish is especially important for those population units that are markedly smaller in size than other units in the population complex. Without high classification success rates, smaller population units are extremely vulnerable to overexploitation.

Participatory Mapping in Browns Canyon National Monument, Colorado (USA)

2017 ◽  
Vol 1 (1) ◽  
pp. 1-16
Author(s):  
John Harner ◽  
Lee Cerveny ◽  
Rebecca Gronewold
Keyword(s):  
Land Management ◽  
Planning Process ◽  
Management Plan ◽  
Bureau Of Land Management ◽  
National Monument ◽  
Resource Managers ◽  
Different Types ◽  
Us Forest Service ◽  
Natural Resource Managers

Natural resource managers need up-to-date information about how people interact with public lands and the meanings these places hold for use in planning and decision-making. This case study explains the use of public participatory Geographic Information System (GIS) to generate and analyze spatial patterns of the uses and values people hold for the Browns Canyon National Monument in Colorado. Participants drew on maps and answered questions at both live community meetings and online sessions to develop a series of maps showing detailed responses to different types of resource uses and landscape values. Results can be disaggregated by interaction types, different meaningful values, respondent characteristics, seasonality, or frequency of visit. The study was a test for the Bureau of Land Management and US Forest Service, who jointly manage the monument as they prepare their land management plan. If the information generated is as helpful throughout the entire planning process as initial responses seem, this protocol could become a component of the Bureau’s planning tool kit.

Integration of Human/Social Dimensions into the Traditional European Model of Natural Resource Education and Management

2005 ◽  
Vol 156 (8) ◽  
pp. 264-268
Author(s):  
James J. Kennedy ◽  
Niels Elers Koch
Keyword(s):  
Natural Resources ◽  
Natural Resource ◽  
Life Forms ◽  
Western World ◽  
Social Dimensions ◽  
Roles And Responsibilities ◽  
Resource Managers ◽  
Natural Resource Managers ◽  
Rural Ecosystem ◽  
Professional Roles And Responsibilities

The increasing diversity, complexity and dynamics of ecosystem values and uses over the last 50 years requires new ways for natural resource managers (foresters, wildlife biologists, etc.)to understand and relate to their professional roles and responsibilities in accommodating urban and rural ecosystem users, and managing the complimentary and conflicting interactions between them. Three stages in Western-world natural resources management are identified and analyzed, beginning with the (1) Traditional stage: natural resources first, foremost and forever, to (2) Transitional stage: natural resource management,for better or worse, involves people, to (3) Relationship stage: managing natural resources for valued people and ecosystem relationships. The impacts of these three perspectives on how natural resource managers view and respond to ecosystems,people and other life-forms is basic and can be profound.

Aquatic Stewardship Education in Theory and Practice

2007 ◽  
Keyword(s):  
Native American ◽  
North America ◽  
Cultural Influences ◽  
Theory And Practice ◽  
Faith Communities ◽  
Specific Expression ◽  
Religious Traditions ◽  
Resource Managers ◽  
Natural Resource Managers ◽  
Stewardship Behavior

<i>Abstract</i>.—Contemporary definitions of aquatic resource stewardship are a specific expression of ethical themes that humankind has wrestled with for millennia. The foundations for a stewardship ethic can be secular or spiritual. Other chapter contributors discuss a range of the secular foundations (e.g., fishing, boating); we discuss the implications of stewardship ethics rooted in religious traditions. Some fisheries professionals recognize religious–cultural influences on aquatic stewardship, such as those seen in Native American or Asian immigrant communities. But fisheries professionals have commonly ignored mainline Judeo-Christian faith traditions as an ethical basis for aquatic stewardship behavior, despite the fact that those traditions inform ethical development for large numbers of people in North America and that denominations within those traditions have increasingly engaged in stewardship-based environmental education and advocacy. The proposition that religious values often form the basis for a stewardship ethic presents several challenges for fisheries professionals striving to foster stewardship behavior. However, a basic understanding of these religious foundations could contribute to an improved practice of stewardship education, through outreach to a new constituency—faith communities. To illustrate this point, we briefly summarize some of the sources for stewardship found in the biblical corpus. We offer three examples of how Christian stewardship principles are manifest in aquatic stewardship programs delivered by faith communities. Models of partnership between natural resource managers and local faith communities are emerging across North America. In revisiting the ethical bases of stewardship and identifying new opportunities for stewardship education partnerships, we hope to demonstrate one more means by which fisheries professionals can bridge from stewardship education in principle to an effective practice of stewardship education.

Mitigating Impacts of Natural Hazards on Fishery Ecosystems

2008 ◽  
Keyword(s):  
Coho Salmon ◽  
Radio Telemetry ◽  
Columbia River ◽  
Future Research ◽  
Army Corps ◽  
The North ◽  
Resource Managers ◽  
North Fork ◽  
Natural Resource Managers ◽  
Mount St Helens

<em>Abstract</em>—The North Fork Toutle River drains the northwest face of Mount St. Helens to the Cowlitz River, a major tributary of the Columbia River in southwestern Washington. In response to the 1980 eruption of Mount St. Helens, the U.S. Army Corps of Engineers constructed a sediment retention structure (SRS) in the North Fork Toutle River watershed to reduce the transport of fine sediment to the lower Cowlitz and Columbia River systems. The SRS was built without fish passage facilities and currently presents a significant barrier to migrating adult salmonids. To facilitate passage of coho salmon <em>Oncorhynchus kisutch </em>and steelhead <em>O. mykiss </em>to the upper watershed, a fish collection facility (FCF) was constructed 1.5 km downstream of the SRS, where fish are currently captured and transported to tributaries upstream of the SRS. We used radio telemetry to evaluate the movement of adult coho salmon and steelhead in the North Fork Toutle River in 2005 and 2006. A total of 40 coho and 42 steelhead were released from four different release sites in varied proportions. Release sites included the FCF, the SRS, and Alder Creek and Hoffstadt Creek, both North Fork Toutle River tributaries upstream of the SRS. Results from this research effort suggest that (1) unlike adult coho, adult steelhead are able to ascend the SRS spillway; (2) upstream adult coho and steelhead passage through the sediment plain is possible but may be flow-dependent; (3) adult coho and steelhead released in Alder Creek and Hoffstadt Creek tend to remain within their respective release tributary; and (4) postspawn steelhead emigration is limited. Future research is required to adequately address factors that influence movement of adult coho and steelhead in the upper North Fork Toutle River. The information resulting from this collaborative effort is enabling natural resource managers to determine whether the SRS spillway is a barrier to anadromous fish, to refine existing trap and haul operations, or, if appropriate, to consider modifying the spillway to enable volitional passage by upstream-migrating fish.

Streams and Dreams and Cross-site Studies

2016 ◽  
Author(s):  
Sherri L. Johnson
Keyword(s):  
Stream Temperature ◽  
Principal Investigator ◽  
Ecosystem Dynamics ◽  
University Of Oklahoma ◽  
Resource Managers ◽  
Long Term Ecological Research ◽  
Natural Resource Managers ◽  
Heat Budgets ◽  
Postdoctoral Fellowship

The influence of the Long-Term Ecological Research (LTER) program on my science has been to broaden my scope through exposure to long-term research and to encourage me to explore major questions across biomes. Communication and outreach with natural resource managers and policy makers has given me insight into translation of science and shaped my research. Through my experiences in the LTER program, I began collaborations with stream ecologists and biogeochemists across sites, which expanded into a high-profile research project that spanned several decades. I encourage scientists to work at LTER sites because they are supportive science communities with a wealth of information to share. Currently, I am a co–principal investigator at the H. J. Andrews Experimental Forest LTER project (AND) in Oregon and have been involved with LTER sites most of my professional life. In 1990, I began graduate research on freshwater shrimp responses to a hurricane at the Luquillo LTER site (LUQ) with Alan Covich, my PhD advisor at the University of Oklahoma. My involvement with LTER research expanded during my postdoctoral fellowship. Through the LTER All Scientists Meetings, I met Julia Jones and other researchers from AND. With their encouragement, I received a National Science Foundation (NSF) Postdoctoral Fellowship Grant in 1996 to examine stream temperature dynamics at AND. After several years at Oregon State University, I was hired by the US Forest Service (USFS) Pacific Northwest Research Station in 2001 as a USFS scientist for AND and became a co–principal investigator in 2002. I have had the benefit of being mentored for multiple years by Fred Swanson and have gradually assumed lead USFS responsibilities for AND. As a stream ecologist, I have studied basic questions and applied issues involving water quality, water quantity, and stream food webs, primarily in forested streams. My research at the LUQ site has examined responses of fresh water shrimp to disturbances and their role in ecosystem dynamics. At AND, my research exploring patterns and controls of stream temperature began as a theoretical landscape-scale question and expanded to examination of temperature responses to flow paths, calculations of heat budgets, and policy implications of forest management (Johnson and Jones 2000; Johnson 2004).

Advances in the Ocean Observing System in the Gulf of Maine: Technical Capabilities and Scientific Results

2011 ◽  
Vol 45 (1) ◽  
pp. 85-97 ◽  
Author(s):  
Neal R. Pettigrew ◽  
C. Patrick Fikes ◽  
M. Kate Beard
Keyword(s):  
Gulf Of Maine ◽  
Meteorological Data ◽  
Coast Guard ◽  
Remote Access ◽  
Resource Managers ◽  
Salinity Anomaly ◽  
Natural Resource Managers ◽  
Scientific Results ◽  
The University ◽  
Ocean Observing

AbstractThe Northeastern Regional Association of Coastal Ocean Observing Systems (NERACOOS), which began in 2008, includes the University of Maine’s comprehensive data buoy array in the Gulf of Maine (GoM). The University of Maine buoy system started in 2001 as part of the Gulf of Maine Ocean Observing System (GoMOOS). The buoys provide a wide variety of oceanographic and marine meteorological data in real time to scientists, environmentalists, the National Weather Service, the U.S. Coast Guard and Canadian Coast Guard, educators, regional natural resource managers, the GoM fishing and maritime industries, and the general public. The GoM observing system is presently undergoing a redesign of the buoy control system to enhance remote access and reduce operational costs. The enhancements will allow remote trouble-shooting and reprogramming of the buoys and subsurface sensors. The system will also accommodate sensors from other research groups and allow them post-deployment control without assistance from our buoy group.Over the near-decade of operation, the system has revealed marked seasonal and interannual variability of the circulation and physical properties of the GoM. In the fall of 2004 to spring of 2005, Doppler currents measured an outflow of deep salty slope waters that suggest a regime shift in the inflow and outflow of transports through the Northeast Channel. During the same period, a salinity anomaly event lowered salinity throughout the GoM by roughly 2 psu by the winter of 2005. In following years, the previously unusual slope outflow and reduced salinity have often reoccurred.

Detecting mortality variation to enhance forage fish population assessments

2018 ◽  
Vol 76 (1) ◽  
pp. 124-135 ◽  
Author(s):  
Nis S Jacobsen ◽  
James T Thorson ◽  
Timothy E Essington
Keyword(s):  
Test Performance ◽  
Size Structure ◽  
Stock Assessment ◽  
Reference Points ◽  
Forage Fish ◽  
Natural Mortality ◽  
Time Varying ◽  
Fishing Mortality ◽  
Catch Data ◽  
Over Time

Abstract Contemporary stock assessment models used by fisheries management often assume that natural mortality rates are constant over time for exploited fish stocks. This assumption results in biased estimates of fishing mortality and reference points when mortality changes over time. However, it is difficult to distinguish changes in natural mortality from changes in fishing mortality, selectivity, and recruitment. Because changes in size structure can be indicate changes in mortality, one potential solution is to use population size-structure and fisheries catch data to simultaneously estimate time-varying natural and fishing mortality. Here we test that hypothesis, using a simulation experiment to test performance for four alternative estimation models that estimate natural and fishing mortality from size structure and catch data. We show that it is possible to estimate time-varying natural mortality in a size-based model, even when fishing mortality, recruitment, and selectivity are changing over time. Finally, we apply the model to North Sea sprat, and show that estimates of recruitment and natural mortality are similar to estimates from an alternative multispecies population model fitted to additional data sources. We recommend exploring potential trends in natural mortality in forage fish assessments using tools such as the one presented here.

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