In 1991, an exotic bivalve called the zebra mussel moved into the Hudson River. Over the past two decades, the prolific species has colonized habitats with hard sediments, becoming the most abundant animal in the rivers freshwater reaches. As competitors in the aquatic food chain, scientists have long speculated that zebra mussels may impact fish. A recent Canadian Journal of Fisheries and Aquatic Sciences article, written by Dr. David L. Strayer of the Institute of Ecosystem Studies (IES) and Drs. Kathryn A. Hattala and Andrew W. Kahnle of the NY State Department of Environmental Conservation (NYSDEC), has revealed that open-water fish species, like the commercially important American shad, are declining in response to the exotic invader.
Invasive species research is often limited by a lack of ecological data on pre-invasion conditions. Since the 1970s, utility companies on the Hudson River have gathered long-term data on juvenile fish populations as a condition of withdrawing cooling water from the river. These surveys began prior to the zebra mussel introduction, allowing for pre and post invasion assessment. Hudson River food web data has been collected by IES since the 1980s. Through analysis of this data, Strayer and colleagues have discovered that open-water fish, such as American shad and striped bass, have decreased in growth and abundance since the zebra mussel invasion. Conversely, species like sunfishes, which prefer vegetated shoreline habitat, have increased significantly.
Many of the open-water fish population declines were large and involved species of commercial or recreational importance, such as American shad and black bass. Strayer notes, "The changes we observed may lead to fewer adults of species such as American shad, and more adults of species such as redbreast sunfish in the Hudson. Maintaining a sustainable fishery for species like American shad, in the face of sharp population reductions, will be challenging. When a rivers ability to support young fish changes, it becomes more difficult to develop and evaluate sound management strategies."
Lori M. Quillen | EurekAlert!
Protecting fisheries from evolutionary change
27.04.2016 | International Institute for Applied Systems Analysis (IIASA)
From waste to resource – how can we turn garbage into gold?
27.04.2016 | DLR Projektträger
Researchers from the Max Planck Institute Stuttgart have developed self-propelled tiny ‘microbots’ that can remove lead or organic pollution from contaminated water.
Working with colleagues in Barcelona and Singapore, Samuel Sánchez’s group used graphene oxide to make their microscale motors, which are able to adsorb lead...
Neutron scattering and computational modeling have revealed unique and unexpected behavior of water molecules under extreme confinement that is unmatched by any known gas, liquid or solid states.
In a paper published in Physical Review Letters, researchers at the Department of Energy's Oak Ridge National Laboratory describe a new tunneling state of...
Honeycomb structures as the basic building block for industrial applications presented using holo pyramid
Researchers of the Alfred Wegener Institute (AWI) will introduce their latest developments in the field of bionic lightweight design at Hannover Messe from 25...
Polymer solar cells can be even cheaper and more reliable thanks to a breakthrough by scientists at Linköping University and the Chinese Academy of Sciences (CAS). This work is about avoiding costly and unstable fullerenes.
Polymer solar cells can be even cheaper and more reliable thanks to a breakthrough by scientists at Linköping University and the Chinese Academy of Sciences...
As one of the leading R&D partners in the development of surface technologies and organic electronics, the Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP will be exhibiting its recent achievements in vacuum coating of ultra-thin glass at SVC TechCon 2016 (Booth 846), taking place in Indianapolis / USA from May 9 – 13.
Fraunhofer FEP is an experienced partner for technological developments, known for testing the limits of new materials and for optimization of those materials...
27.04.2016 | Event News
15.04.2016 | Event News
12.04.2016 | Event News
29.04.2016 | Physics and Astronomy
29.04.2016 | Health and Medicine
29.04.2016 | Life Sciences