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Jeff C. Jolley

Publications and source records attributed to Jeff C. Jolley.

5 recordsLinked to original sources
USGS2026

Beyond technical expertise: The role of mindset, interpersonal, and intrapersonal skills in the development of fisheries professionals

Objective Recognized as essential components for success, mindset and inter- and intrapersonal skills (often referred to as soft skills) play a crucial role in the growth and effectiveness of individuals throughout their careers. Individuals with strong inter- and intrapersonal skills and a mindset open to growth can efficiently navigate complex challenges that may involve working with diverse stakeholder groups, managing interdisciplinary teams, or resolving conflicts in ways that allow them to excel beyond their technical skill sets. Although formal education of natural resources professionals (and many other professions) generally prioritizes technical skills, cultivating inter- and intrapersonal skills and a growth mindset is critical to success. Methods Drawing on presentations and discussion from an early-career symposium at the 2023 American Fisheries Society Conference, we summarize skill sets valuable for success in fisheries and natural resources. Results We provide an overview of the roles mindset and inter- and intrapersonal skills have in developing a career, how to use these competencies to navigate natural resources professions, and actions for enhancing personal skills. This paper aims to provide a compendium of information and lessons learned from natural resources professionals with diverse experiences and to emphasize familiar concepts to help formalize their discussion in the fisheries profession. Conclusion Fisheries and other natural resource fields have become increasingly interdisciplinary, necessitating a broad suite of skills to effectively communicate across disciplines, convey multiple data types, and make decisions to address complex problems. Inter- and intrapersonal skill sets are foundational to successfully navigating the fisheries profession. Moreover, personal skills transcend our profession into our everyday lives, thus strengthening personal skills is a worthy endeavor.

Fisheries↗
USGS2023

Movement ecology of diploid and triploid grass carp in a large reservoir and upstream tributaries

Grass carp Ctenopharyngodon idella , is an herbivorous fish originally brought to North America from Asia in 1963 to control nuisance aquatic vegetation. Since their arrival, detrimental alterations to aquatic ecosystems have sometimes occurred in waterways where they were initially stocked and into which they have escaped. The movements of grass carp from lentic systems into tributaries required for spawning is poorly understood, and understanding environmental conditions associated with upstream migrations may aid in management of the species. We stocked 43 fertile diploid and 43 sterile triploid grass carp implanted with acoustic transmitters into Truman Reservoir, Missouri, USA between January 2017 and October 2018 to characterize movements during spring and summer when spawning conditions occur. Twenty fish (11 diploid/9 triploid) exhibited upstream migration behavior in the Osage River, a major tributary, in 2018 and 2019. Migration primarily occurred in April and May, during high discharge events associated with increasing river stage when water temperatures were between 15 and 28°C. Observed migrations ranged from 3.0–108 river km in length, and six individuals were observed making multiple upstream migrations in one season. Eleven fish initiated upstream migrations while in the lentic main body of the reservoir. These findings provide some evidence for upstream migrations by diploid and triploid grass carp as well both lake and river residents. Evidence of similar upstream migration behavior by both diploid and triploid grass carp suggests that triploids may be suitable surrogates for diploids for study of movement ecology. Removal efforts in tributaries targeting periods of increasing river stage during spring may provide the best opportunity of encountering large concentrations of grass carp.

Missouri↗
USGS2021

Winter habitat selection and efficacy of telemetry to aid Grass Carp removal efforts in a large reservoir

Grass Carp Ctenopharyngodon idella were introduced in North America to control aquatic vegetation in small, closed systems. However, when they escape into larger systems in which they can reproduce, they have the potential to cause significant declines and alterations in aquatic vegetation communities. These alterations can in turn affect native species that are dependent on aquatic vegetation. Increased captures and observations of spawning have elevated concerns about Grass Carp establishment in new locations, with particular concern for establishment in Lake Erie and its tributaries. Recent efforts using telemetered fish that co-locate with wild conspecifics, sometimes in aggregations that are susceptible to harvest, have been used successfully to control invasive Common Carp Cyprinus carpio populations. If Grass Carp aggregate in winter similarly to Common Carp, they might be susceptible to similar control or harvest methods. During the winters (December–March) of 2017–2019, we tracked 86 Grass Carp tagged with acoustic transmitters in Truman Reservoir, Missouri, to evaluate winter habitat selection and to determine the effectiveness of using tagged fish in locating and removing wild fish by comparing harvest at locations of tagged fish to harvest at control sites that we believed were suitable Grass Carp habitat. Discrete-choice models showed that Grass Carp exhibited strong selection for shallow water, as 75% of locations were in littoral habitats with depths of 3 m or less. On average, we harvested more fish at sites where tagged fish were located (3.6 fish/attempt) than at control sites (1.2 fish/attempt). Full guts in individuals that were harvested may indicate that fish were using shallow-water habitats to feed. Our results suggested that Grass Carp did not usually form large winter aggregations, and although targeting locations with tagged fish slightly increased harvest success compared to efforts without them, efforts to reduce populations via harvest may be difficult in large systems when fish are widely dispersed.

Missouri↗
USGS2012

Priority effects among young‐of‐the‐year fish: reduced growth of bluegill sunfish (Lepomis macrochirus) caused by yellow perch (Perca flavescens)?

1. When available, Daphnia spp. are often preferred by age-0 yellow perch and bluegill sunfish because of energetic profitability. We hypothesised that predation by age-0 yellow perch could lead to a midsummer decline (MSD) of Daphnia spp. and that priority effects may favour yellow perch because they hatch before bluegill, allowing them to capitalise on Daphnia spp. prior to bluegill emergence. 2. Data were collected from 2004 to 2010 in Pelican Lake, Nebraska, U.S.A. The lake experienced a prolonged MSD in all but 1 year (2005), generally occurring within the first 2 weeks of June except in 2008 and 2010 when it occurred at the end of June. MSD timing is not solely related to seasonal patterns of age-0 yellow perch consumption. Nevertheless, when Daphnia spp. biomass was low during 2004 and 2006–2010 (<4 mg wet weight L −1 ), predation by age-0 yellow perch seems to have suppressed Daphnia spp. biomass (i.e. <1.0 mg wet weight L −1 ). The exception was 2005 when age-0 yellow perch were absent. 3. Growth of age-0 bluegill was significantly faster in 2005, when Daphnia spp. were available in greater densities (>4 mg wet weight L −1 ) compared with the other years (<0.2 mg wet weight L −1 ). 4. We conclude that age-0 yellow perch are capable of reducing Daphnia biomass prior to the arrival of age-0 bluegill, ultimately slowing bluegill growth. Thus, priority effects favour age-0 yellow perch when competing with age-0 bluegill for Daphnia . However, these effects may be minimised if there is a shorter time between hatching of the two species, higher Daphnia spp. densities or lower age-0 yellow perch densities.

Nebraska↗