Aquaculture and Fisheries Commons^™

The Future Of Recreational Fisheries: Advances In Science, Monitoring, Management, And Practice, Jacob W. Brownscombe, Kieran Hyder, Warren Potts, Kyle L. Wilson, Kevin L. Pope, Andy J. Danylchuk, Steven J. Cooke, Adrian Clarke, Robert Arlinghaus, John R. Post

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Recreational fisheries (RF) are complex social-ecological systems that play an important role in aquatic environments while generating significant social and economic benefits around the world. The nature of RF is diverse and rapidly evolving, including the participants, their priorities and behaviors, and the related ecological impacts and social and economic benefits. RF can lead to negative ecological impacts, particularly through overexploitation of fish populations and spread of non-native species and genotypes through stocking. Hence, careful management and monitoring of RF is essential to sustain these ecologically and socioeconomically important resources. This special issue on recreational fisheries contains diverse research, syntheses, …

Age-0 Walleye Sander Vitreus Display Length-Dependent Diet Shift To Piscivory, Christopher S. Uphoff, Casey W. Schoenebeck, Keith D. Koupal, Kevin L. Pope, W. Wyatt Hoback

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

The ontogenetic diet shift to piscivory can be energetically beneficial for fish growth and allows larger, more energetically profitable prey to be consumed. A shift to piscivory may be easier for longer individuals within a cohort due to larger gape size, and an early shift is likely advantageous, potentially leading to increased growth rates and survival. Such length-dependent ontogenetic diet shifts may explain the intracohort variability in length that is common for age-0 walleye (Sander vitreus). The objectives of this study were to describe seasonal intracohort variability in length, identify the timing of the shift to piscivory and …

Ecosystem Size Predicts Social-Ecological Dynamics, Mark A. Kaemingk, Christopher J. Chizinski, Craig R. Allen, Kevin L. Pope

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Recreational fisheries are complex adaptive systems that are inherently difficult to manage because of heterogeneous user groups (consumptive vs. nonconsumptive) that use patchily distributed resources on the landscape (lakes, rivers, coastlines). There is a need to identify which system components can effectively predict and be used to manage nonlinear and cross-scale dynamics within these systems. We examine how ecosystem size or water body size can be used to explain complicated and elusive angler-resource dynamics in recreational fisheries. Water body size determined angler behavior among 48 Nebraska, U.S.A. water bodies during an 11- year study. Angler behavior was often unique and …

Simulating Detection-Censored Movement Records For Home Range Analysis Planning, Lyndsie S. Wszola, Victoria L. Simonsen, Lucía Corral, Christopher J. Chizinski, Joseph J. Fontaine

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Home range estimation is an important analytical method in applied spatial ecology, yet best practices for addressing the effects of spatial variation in detection probability on home range estimates remain elusive. We introduce the R package “DiagnoseHR,” simulation tools for assessing how variation in detection probability arising from landscape, animal behavior, and methodological processes affects home range inference. We demonstrate the utility of simulation methods for home range analysis planning by comparing bias arising from three home range estimation methods under multiple detection scenarios. We simulated correlated random walks in three landscapes that varied in detection probability and constructed home …

Ecosystem Based Fisheries Management (Ebfm) Risk Assessment Of The Western Australian Sea Cucumber Fishery, F J. Webster, Anthony M. Hart

WA Marine Stewardship Council report series

This report provides a comprehensive overview of the commercial Western Australian Sea Cucumber Fishery (SCF) and the outcomes from the 2016 ecological risk assessment for this fishery. Two key species, sandfish (Holothuria scabra) and redfish (Actinopyga echinites), are targeted by the commercial SCF through hand collection by diving and wading primarily in shallow waters of northern WA.

The Influence Of Habitat Preference On Longitudinal Population Composition And Distribution Of Groupers (Serranidae) In Chumbe Island Coral Park, Zanzibar Tanzania, Caroline Daley

Independent Study Project (ISP) Collection

A survey of six common grouper (Serranidae) species was conducted on both the western protected and eastern unprotected reefs around Chumbe Island. Species, estimated maturity, and fundamental niche and general habitat preference was extrapolated based on observed realized niche and qualified according to substrate, depth, slope position, and general reef region. Abundance, biomass density, and biodiversity of Serranid populations were compared among locations on the reef with habitat preference in mind in order to best assess how habitat influences population composition, distribution, and health. The results of this study provide depth to previous research on the protected reef and indicate …

Growth Of Pelagic Age-0 Yellow Perch In Relation To Hatch Dates And Water Temperature In North-Central Minnesota Lakes, Ethan Karppinen

Biology Graduate Theses

Exposure to consistent water warming rates and access to abundant populations of edible sized zooplankton affects growth and increases the probability of survival for newly hatched Yellow Perch Perca flavescens. Seven lakes with varying physical characteristics were selected in north-central Minnesota to study abiotic (water temperature) and biotic (zooplankton community and fish growth) progressions during the spring and early summer (April-June). Mean water temperatures from ice-out to 28 June (11.98-14.62 °C) had significant relationships with mean depth (P < 0.01, R? = 0.85), max depth (P < 0.01, R? = 0.73), and total volume (P < 0.01, R2 = 0.54). Hatch periods ranged from 13 to 19 days in 2015 and 13 to 25 days in 2016. Cumulative degree-days (CDD) were used to predict Yellow Perch hatch periods and explain growth. CDD predicted 21-81% of hatch periods in 2015 and 11-50% in 2016. Mean predicted total lengths at 28 June were 19.65-30.41 mm in 2015 and 20.88-28.54 mm in 2016. There was a significant relationship between CDD and predicted total length (R? = 0.62, P < 0.01) to explain differences in Yellow Perch total length while inhabiting the pelagic zone. Observed gape measurements were highly correlated with predicted gapes from the Schael formula (R? = 0.89, P < 0.01) that was used to assess the availability of edible sized zooplankton for age-0 Yellow Perch in each lake. No predator-prey mismatches were found and earlier hatch dates produced age-0 Yellow Perch with greater predicted total lengths in late June on the majority of lakes. This suggests that earlier hatched Yellow perch have an advantage over later hatched Yellow Perch in attaining greater lengths by late June. Our study provides information on a variety of physical and biological progressions in lakes, which may be used for fisheries management practices in the future.

Ecological Neighborhoods As A Framework For Umbrella Species Selection, Erica F. Stuber, Joseph J. Fontaine

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Umbrella species are typically chosen because they are expected to confer protection for other species assumed to have similar ecological requirements. Despite its popularity and substantial history, the value of the umbrella species concept has come into question because umbrella species chosen using heuristic methods, such as body or home range size, are not acting as adequate proxies for the metrics of interest: species richness or population abundance in a multi-species community for which protection is sought. How species associate with habitat across ecological scales has important implications for understanding population size and species richness, and therefore may be a …

Population Characteristics Of A Closed Northern Pike (Esox Lucius) Catch-And-Release Population In Minnesota, John Kempe

Biology Graduate Theses

Literature regarding catch-and-release populations of Northern Pike are rare and provide a unique perspective on their population dynamics. Shingobee Lake is a 64- ha mesotrophic lake with a maximum depth of 12.2 m located in northern Minnesota. Northern Pike fishing has been catch-and-release only since 2005, and there are no public accesses on the lake. Annual ice-out trap-netting occurred from 2009-2017, and a sizable amount of the Northern Pike recaptured via trapnet or angling had been previously tagged (37-59%). The lack of exploitation and high tagging percentage provided a unique opportunity to study the population dynamics of Northern Pike. Shinogbee’s …

Synchrony — An Emergent Property Of Recreational Fisheries, Mark A. Kaemingk, Christopher J. Chizinski, Keith Hurley, Kevin L. Pope

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

1. Recreational fisheries are traditionally managed at local scales, but more effective management could be achieved using a cross-scale approach. To do this, we must first understand how local processes scale up to influence landscape patterns between anglers and resources. We highlight how population-based synchrony methods, used in conjunction with a complex-adaptive-systems framework, can reveal emergent spatial properties within social-ecological systems such as recreational fisheries.

2. Herein, we quantified the level of spatial synchrony in angler behaviour, defined the relationship between angler synchrony and distance among waterbodies, and highlighted social-ecological attributes contributing to these patterns. We leveraged a 111 waterbody-year …

Summary Of The Stock Structure Information Used For Determining Spatial Management Of The Index Species For The Scalefish Resources Of Northern Western Australia, Daniel J. Gaughan, Stephen J. Newman, Corey B. Wakefield

WA Marine Stewardship Council report series

This paper was specifically developed in response to issues raised in an assessment of the Pilbara Trap Managed Fishery (PTMF) against the fishery sustainability standard of the Marine Stewardship Council (MSC).

Resource Assessment Report Western Australian Sea Cucumber Resource, Anthony M. Hart, D. V. Murphy, N Caputi, Alexander Hesp, E. A. Fisher

WA Marine Stewardship Council report series

This document provides a cumulative description and assessment of the Sea Cucumber Resource and all of the fishing activities (i.e. fisheries / fishing sectors) affecting this resource in Western Australia (WA). The overall resource comprises two main species (sandfish Holothuria scabra and redfish Actinopyga echinites), and few minor species that inhabit the tropical shallow continental shelf waters of the North Coast Bioregion.

Resource Assessment Report Western Australian Octopus Resource, Anthony M. Hart, Daniel Murphy, Alastair Harry, E. A. Fisher

WA Marine Stewardship Council report series

This document provides a cumulative description and assessment of the Octopus Resource and all of the fishing activities (i.e. fisheries / fishing sectors) affecting this resource in Western Australia (WA). The overall resource essentially comprises a single species of octopus, Octopus aff. tetricus, which occurs in inshore waters to 70 m depth from Shark Bay to Esperance.

Growth Rate And Hatch Date Of Age-0 Fishes On Leech Lake, Minnesota Before Zebra Mussel Establishment, Kayla Morey, Emily Larson

Journal of Earth and Life Science

The introduction of an invasive species to an ecosystem is considered a very severe environmental problem. Zebra Mussel veligers Dreissena polymorpha have recently been found in Leech Lake, Minnesota, and are likely going to have a large influence on this ecosystem. Zebra Mussels are filter-feeders that rely on phytoplankton and zooplankton as their main source of energy. A shift in populations of plankton due to Zebra Mussels may affect the growth rates of larval fish. Median hatch dates and growth rates were estimated from four age-0 fish species (Yellow Perch Perca flavescens, Walleye Sander vitreus, Smallmouth Bass Micropterus …

Thermal Tolerance Limits Of The Chinese Mystery Snail (Bellamya Chinensis): Implications For Management, Jessica L. Burnett, Kevin L. Pope, Alec Wong, Craig R. Allen, Danielle Haak, Bruce J. Stephen, Daniel R. Uden

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

The Chinese mystery snail, Bellamya chinensis (Gray, 1834) is a gastropod native to East Asia and is considered an invasive species in North America where its impacts on native species and ecosystems are not well understood. Scientific literature describing its biology and life history are sparse. Thermal tolerance limits, or the maximum and minimum temperature under which a species can survive, are key to identifying the potential geographical range of a species. The ability of managers to control invasive species is directly impacted by the thermal tolerance limits of a species. We attempted to identify the thermal tolerance limits of …

The Effect Of Size On Juvenile Green Sturgeon (Acipenser Medirostris) Behavior Near Water-Diversion Fish Screens, Jamilynn B. Poletto, Dennis E. Cocherell, Natalie Ho, Joseph J. Cech Jr., A. Peter Klimley, Nann A. Fangue

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Anthropogenic water management projects and facilities that alter the local and regional hydrology of riverine environments greatly influence the behavior, physiology, and survival of native fishes. To mitigate for losses of native fishes at these structures, many are outfitted with fish-exclusion screens to reduce entrainment. The effect of fish size and age on behavior near fish screens, however, is largely unknown. Therefore, we tested two size classes of juvenile green sturgeon (Acipenser medirostris; small, early juveniles: 9.2 ± 0.2 cm fork length [FL], 6.9 ± 0.3 g; intermediate juveniles: 18.8 ± 0.2 cm FL, 36.9 ± 0.8 g) …

Resilience In Environmental Risk And Impact Assessment: Concepts And Measurement, David G. Angeler, Craig R. Allen, Ahjond S. Garmestani, Kevin L. Pope, Dirac L. Twidwell Jr, Micro Bunschuh

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Different resilience concepts have different assumptions about system dynamics, which has implications for resilience-based environmental risk and impact assessment. Engineering resilience (recovery) dominates in the risk assessment literature but this definition does not account for the possibility of ecosystems to exist in multiple regimes. In this paper we discuss resilience concepts and quantification methods. Specifically, we discuss when a system fails to show engineering resilience after disturbances, indicating a shift to a potentially undesired regime. We show quantification methods that can assess the stability of this new regime to inform managers about possibilities to transform the system to a more …

Agroecology For The Shrinking City, Dustin L. Herrmann, Wen-Ching Chuang, Kristen Schawrz, Timothy M. Bowles, Ahjond S. Garmestani, William D. Shuster, Tarsha Eason, Matthew E. Hopton, Craig R. Allen

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Many cities are experiencing long-term declines in population and economic activity. As a result, frameworks for urban sustainability need to address the unique challenges and opportunities of such shrinking cities. Shrinking, particularly in the U.S., has led to extensive vacant land. The abundance of vacant land reflects a loss of traditional urban amenities, economic opportunity, neighbors, businesses, and even basic city services and often occurs in neighborhoods with socially and economically vulnerable or underserved populations. However, vacant land also provides opportunities, including the space to invest in green infrastructure that can provide ecosystem services and support urban sustainability. Achieving desirable …

Age-0 Walleye Growth Rates Following Spiny Water Flea Bythotrephes Longimanus Invasion, Joseph Amundson

Journal of Earth and Life Science

Within Voyageurs National Park, spiny water flea Bythotrephes longimanus has reduced Lake Kabetogama and Rainy Lake native zooplankton biomass during summer peak by 40-60%. Subsequently, planktivorous age-0 Yellow Perch Perca flavescens growth has decreased. A possible trophic cascade may influence predatory fish growth rates like that of age-0 Walleye Sander vitreus. Using seine net and electrofishing data, age-0 Walleye growth rates were modeled as a linear function of growing degree days (GDD) and the slope was compared between pre- and post-spiny water flea establishment. Nearby Lake Vermilion, assumed to have been unaffected by spiny water flea until 2015 and …

Opportunities And Challenges For Big Data Ornithology, Frank A. La Sorte, Christopher A. Lepczyk, Jessica L. Burnett, Allen H. Hurlbert, Morgan W. Tingley, Benjamin Zuckerberg

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Recent advancements in information technology and data acquisition have created both new research opportunities and new challenges for using big data in ornithology. We provide an overview of the past, present, and future of big data in ornithology, and explore the rewards and risks associated with their application. Structured data resources (e.g., North American Breeding Bird Survey) continue to play an important role in advancing our understanding of bird population ecology, and the recent advent of semistructured (e.g., eBird) and unstructured (e.g., weather surveillance radar) big data resources has promoted the development of new empirical perspectives that are generating novel …

A Framework For Tracing Social–Ecological Trajectories And Traps In Intensive Agricultural Landscapes, Daniel R. Uden, Craig R. Allen, Francisco Munoz-Arriola, Gengxin Ou, Nancy Shank

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Charting trajectories toward sustainable agricultural development is an important goal at the food–energy–water–ecosystem services (FEWES) nexus of agricultural landscapes. Social–ecological adaptation and transformation are two broad strategies for adjusting and resetting the trajectories of productive FEWES nexuses toward sustainable futures. In some cases, financial incentives, technological innovations, and/or subsidies associated with the short-term optimization of a small number of resources create and strengthen unsustainable feedbacks between social and ecological entities at the FEWES nexus. These feedbacks form the basis of rigidity traps, which impede adaptation and transformation by locking FEWES nexuses into unsustainable trajectories characterized by control, stability, and efficiency, …

Quantifying Uncertainty And Trade-Offs In Resilience Assessments, Craig R. Allen, Hannah E. Birgé, David G. Angeler, Craig A. Arnold, Brian C. Chaffin, Daniel A. Decaro, Ahjond S. Garmestani, Lance Gunderson

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Several frameworks have been developed to assess the resilience of social-ecological systems, but most require substantial data inputs, time, and technical expertise. Stakeholders and practitioners often lack the resources for such intensive efforts. Furthermore, most end with problem framing and fail to explicitly address trade-offs and uncertainty. To remedy this gap, we developed a rapid survey assessment that compares the relative resilience of social-ecological systems with respect to a number of resilience properties. This approach generates large amounts of information relative to stakeholder inputs. We targeted four stakeholder categories: government (policy, regulation, management), end users (farmers, ranchers, landowners, industry), agency/public …

A Method To Detect Discontinuities In Census Data, Chris Barichievy, David G. Angeler, Tarsha Eason, Ahjond S. Garmestani, Kirsty L. Nash, Craig A. Stow, Shana Sundstrom, Craig R. Allen

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

The distribution of pattern across scales has predictive power in the analysis of complex systems. Discontinuity approaches remain a fruitful avenue of research in the quest for quantitative measures of resilience because discontinuity analysis provides an objective means of identifying scales in complex systems and facilitates delineation of hierarchical patterns in processes, structure, and resources. However, current discontinuity methods have been considered too subjective, too complicated and opaque, or have become computationally obsolete; given the ubiquity of discontinuities in ecological and other complex systems, a simple and transparent method for detection is needed. In this study, we present a method …

Effects Of Large-Scale Wetland Loss On Network Connectivity Of The Rainwater Basin, Nebraska, Bram H. F. Verheijen, Dana M. Varner, David A. Haukos

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Context The Rainwater Basin region in south-central Nebraska supports a complex network of spatiallyisolated wetlands that harbor diverse floral and faunal communities. Since European settlement, many wetlands have been lost from the network, which has increased distances among remaining wetlands. As a result, populations of wildlife species with limited dispersal capabilities may have become isolated and face greater local extinction risks.

Objectives We compared the pre-European settlement and current extent of the Rainwater Basin network to assess the effects of wetland losses on network connectivity for a range of maximum dispersal distances.

Methods We constructed network models for a range …

Synchrony - An Emergent Property Of Recreational Fisheries, Mark A. Kaemingk, Christopher J. Chizinski, Keith L. Hurley, Kevin L. Pope

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

No abstract provided.

Bipartite Networks Improve Understanding Of Effects Of Waterbody Size And Angling Method On Angler–Fish Interactions, Christopher J . Chizinski, Dustin R. Martin, Daizaburo Shizuka, Kevin L. Pope

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Networks used to study interactions could provide insights to fisheries. We compiled data from 27 297 interviews of anglers across waterbodies that ranged in size from 1 to 12 113 ha. Catch rates of fish species among anglers grouped by species targeted generally differed between angling methods (bank or boat). We constructed angler–catch bipartite networks (angling method specific) between anglers and fish and measured several network metrics. There was considerable variation in networks among waterbodies, with multiple metrics influenced by waterbody size. Number of species-targeting angler groups and number of fish species caught increased with increasing waterbody size. Mean number …

Variation In Angler Distribution And Catch Rates Of Stocked Rainbow Trout In A Small Reservoir, Brian S. Harmon, Dustin R. Martin, Christopher J . Chizinski, K. L. Pope

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

We investigated the spatial and temporal relationship of catch rates and angler party location for two days following a publicly announced put-and-take stocking of rainbow trout (Oncorhynchus mykiss). Catch rates declined with time since stocking and distance from stocking. We hypothesized that opportunity for high catch rates would cause anglers to fish near the stocking location and disperse with time, however distance between angler parties and stocking was highly variable at any given time. Spatially explicit differences in catch rates can affect fishing quality. Further research could investigate the variation between angler distribution and fish distribution within a …

Population Characteristics Of Shovelnose Sturgeon During Low- And High-Water Conditions In The Lower Platte River, Nebraska, Jeremy J. Hammen, Martin J. Hamel, Matthew L. Rugg, Edward J. Peters, Mark A. Pegg

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Cycles of low- and high-water periods (i.e., years) in river systems are natural occurrences, but understanding how cyclical climatological patterns affect fishes, especially long-lived species, is unclear. We assessed Shovelnose Sturgeon population dynamics between a period of low- (2001-2004) and high- (2009-2012) water years in the lower Platte River, Nebraska. Low-flow periods in the lower Platte River can cause disconnection(s) between upstream and downstream reaches resulting in isolated pools and elevated water temperatures leading to stressful situations for aquatic life and possible mortality. Our data show no measurable differences between key population indices between flow condition periods which is consistent …

Resilience Concepts In Psychiatry Demonstrated With Bipolar Disorder, David G. Angeler, Craig R. Allen, Maj-Liz Persson

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Background: The term resilience describes stress–response patterns of subjects across scientific disciplines. In ecology, advances have been made to clearly distinguish resilience definitions based on underlying mechanistic assumptions. Engineering resilience (rebound) is used for describing the ability of subjects to recover from adverse conditions (disturbances), and is the rate of recovery. In contrast, the ecological resilience definition considers a systemic change: when complex systems (including humans) respond to disturbances by reorganizing into a new regime (stable state) where structural and functional aspects have fundamentally changed relative to the prior regime. In this context, resilience is an emergent property of complex …

Translating Statistical Species-Habitat Models To Interactive Decision Support Tools, Lyndsie S. Wszola, Victoria L. Simonsen, Erica F. Stuber, Caitlyn R. Gillespie, Lindsey N. Messinger, Karie L. Decker, Jeffrey J. Lusk, Christopher F. Jorgensen, Andrew A. Bishop, Joseph J. Fontaine

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Understanding species-habitat relationships is vital to successful conservation, but the tools used to communicate species-habitat relationships are often poorly suited to the information needs of conservation practitioners. Here we present a novel method for translating a statistical species-habitat model, a regression analysis relating ring-necked pheasant abundance to landcover, into an interactive online tool. The Pheasant Habitat Simulator combines the analytical power of the R programming environment with the user-friendly Shiny web interface to create an online platform in which wildlife professionals can explore the effects of variation in local landcover on relative pheasant habitat suitability within spatial scales relevant to …