As one of the most highly prized game fish in the upper Midwest, muskellunge (also known as muskies) and northern pike help support a $20 billion sport fishing industry. Facing declines in natural reproduction, a team of scientists, including a Michigan State University inland fisheries researcher, has developed a list of research and management needs to help keep the fish -- and the industry -- thriving.
'Muskies and northern pike are the largest predatory fishes in this region, making them high-profile fisheries,' explained Joe Nohner, doctoral student in fisheries at the MSU Center for Systems Integration and Sustainability. 'By supporting strong pike and muskellunge populations, we can provide better fishing opportunities and a strong recreational fishing industry.'
Working with scientists from across the region, Nohner helped prioritize research and management needs for muskie and northern pike, including:
According to Nohner, most of the past research and management programs have focused on adult fish and protection from overfishing. While managers and anglers focus on adult fish populations, some fisheries have been undercut by declining natural reproduction. Fish populations have been kept up through stocking, so in many areas the fishery isn't self-sustaining.
'We believe we need a more holistic approach to managing these fishes,' Nohner said. 'We want to include genetics, habitat needs at all life stages, and include the effects of humans in the equation. It's somewhat daunting, but new technologies will help us meet the challenge.'
Nohner has started tackling part of the challenge himself, creating a computer mapping technique to predict the location of muskie spawning habitats.
By studying 28 lakes in northern Wisconsin, he and his colleague found that muskies preferred spawning in bays with moderately sloping lake bottoms and that the fish also preferred not to spawn along shorelines with houses or other development.
'Lakes with more development are less likely to be muskie spawning habitats,' Nohner said. 'Fisheries managers, county commissioners and lakeshore property owners may have to consider where development is located and how that will affect the fish.
'We found that muskie spawning site selection may be more complex than previously thought,' he continued. 'There is not just one particular characteristic that makes the fish gravitate to an area for spawning. There seem to be several factors that affect the location, which is why we need a modelling program to help identify those critical habitats.'
The paper 'Muskellunge and northern pike ecology and management: important issues and research needs' is published in the June issue of Fisheries. Besides Nohner, other authors are Derek Crane, John Farrell and Kevin Kapuscinski, of the State University of New York-Syracuse; Loren Miller, of the Minnesota Department of Natural Resources; James Diana, of the University of Michigan; and John Casselman, of Queen's University.
The paper 'Muskellunge spawning site selection in northern Wisconsin and a GIS-based predictive model' is published in the February issue of the North American journal of Fisheries Management. Nohner and Diana are the authors. The research was funded by the Wisconsin Department of Natural Resources, the Musky Clubs Alliance of Wisconsin, the University of Michigan and the Alvan Macauley Fellowship.
The Center for Systems Integration and Sustainability integrates ecology with socioeconomics, demography and other disciplines to conduct cutting-edge research on ecological sustainability on local, national and global scales.
Sue Nichols | EurekAlert!
Kakao in Monokultur verträgt Trockenheit besser als Kakao in Mischsystemen
18.09.2017 | Georg-August-Universität Göttingen
Ultrasound sensors make forage harvesters more reliable
28.08.2017 | Fraunhofer-Institut für Zerstörungsfreie Prüfverfahren IZFP
Plants and algae use the enzyme Rubisco to fix carbon dioxide, removing it from the atmosphere and converting it into biomass. Algae have figured out a way to increase the efficiency of carbon fixation. They gather most of their Rubisco into a ball-shaped microcompartment called the pyrenoid, which they flood with a high local concentration of carbon dioxide. A team of scientists at Princeton University, the Carnegie Institution for Science, Stanford University and the Max Plank Institute of Biochemistry have unravelled the mysteries of how the pyrenoid is assembled. These insights can help to engineer crops that remove more carbon dioxide from the atmosphere while producing more food.
A warming planet
Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.
The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...
Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...
Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!
When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...
For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.
Multiferroics are materials that simultaneously react to electric and magnetic fields. These two properties are rarely found together, and their combined...
19.09.2017 | Event News
12.09.2017 | Event News
06.09.2017 | Event News
22.09.2017 | Life Sciences
22.09.2017 | Medical Engineering
22.09.2017 | Physics and Astronomy