Research published today in the international journal Oecologia sheds new light on the dispersal of marine fish in their larval stages, important information for the effective design of marine protected areas (MPAs), a widely advocated conservation tool.
Using a novel genetic analysis, researchers at the University of Windsor, Canada, and the United Nations University's Canadian-based Institute for Water, Environment and Health (UNU-INWEH) studied dispersal and connectivity among populations of the bicolor damselfish -- a species common to Caribbean coral reefs and a convenient proxy for many coral reef fish species with similar biology, including a typical 30-day larval stage.
Using samples of newly settled juvenile fish from sites in Belize and Mexico, they traced the origins of hundreds of individual fish larvae back to putative source populations.
"This is the first time that genetic 'assignment tests' have been used to delineate the pattern of connectivity for a marine fish in a region of this size (approximately 6,000 square kilometers)," says lead author Derek Hogan of the University of Windsor, now at University of Wisconsin.
"We found that larvae of this species, on average, traveled 77 km from home in the 30-day larval period," says Dr. Hogan. "Although some fish remained close to home in the same period, some traveled almost 200 km - roughly the distance from New York City to Albany - an impressive feat for a larva about the size of a baby fingernail."
The scientists were surprised to find that patterns of larval dispersal among reefs changed from year to year, driven perhaps by changes in oceanographic currents or meteorological events.
"These results show that it is possible to characterize the pattern of connectivity for selected species, with considerable detail" says co-author Prof. Daniel Heath of the University of Windsor.
"These studies are invaluable for understanding how to design networks of marine protected areas effectively," says Dr. Hogan. "The functioning, and therefore the success, of networks of MPAs designed for conserving species depends fundamentally on our deep understanding of larval migrations."
The authors caution that more work is needed to determine factors that cause larval dispersal to fluctuate from year to year.
"Our results reveal that developing a precise understanding of connectivity patterns is going to be more difficult than previously assumed, because they vary through time," says co-author Peter F. Sale, Assistant Director at UNU-INWEH.
"Long-term, we need to be building models that can simulate connectivity in ways that reproduce these year-to-year changes. Models that can do that will be broadly applicable and powerful management tools."
The study is part of the Coral Reef Targeted Research Project (CRTR), a World Bank and University of Queensland-led project funded by the Global Environment Facility. CRTR involves over 100 investigators from universities and research centers worldwide. Its Connectivity Working Group, led by Dr. Sale and managed by UNU-INWEH, focuses its research activity primarily in the western Caribbean.
These results add to the CRTR Project's impressive total of new science results on selected questions deemed key to improving management of coral reef systems worldwide.
Further more information:The Connectivity Program:
The University of Windsor is an internationally-oriented, multi-disciplined institution that actively fosters an atmosphere of close cooperation between faculty and students, creating a unifying atmosphere of excellence across all of its faculties to encourage lifelong learning, teaching, research and discovery.
Terry Collins | EurekAlert!
Dispersal of Fish Eggs by Water Birds – Just a Myth?
19.02.2018 | Universität Basel
Removing fossil fuel subsidies will not reduce CO2 emissions as much as hoped
08.02.2018 | International Institute for Applied Systems Analysis (IIASA)
At the Hannover Messe 2018, the Bundesanstalt für Materialforschung und-prüfung (BAM) will show how, in the future, astronauts could produce their own tools or spare parts in zero gravity using 3D printing. This will reduce, weight and transport costs for space missions. Visitors can experience the innovative additive manufacturing process live at the fair.
Powder-based additive manufacturing in zero gravity is the name of the project in which a component is produced by applying metallic powder layers and then...
Physicists at the Laboratory for Attosecond Physics, which is jointly run by Ludwig-Maximilians-Universität and the Max Planck Institute of Quantum Optics, have developed a high-power laser system that generates ultrashort pulses of light covering a large share of the mid-infrared spectrum. The researchers envisage a wide range of applications for the technology – in the early diagnosis of cancer, for instance.
Molecules are the building blocks of life. Like all other organisms, we are made of them. They control our biorhythm, and they can also reflect our state of...
University of Connecticut researchers have created a biodegradable composite made of silk fibers that can be used to repair broken load-bearing bones without the complications sometimes presented by other materials.
Repairing major load-bearing bones such as those in the leg can be a long and uncomfortable process.
Study published in the journal ACS Applied Materials & Interfaces is the outcome of an international effort that included teams from Dresden and Berlin in Germany, and the US.
Scientists at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) together with colleagues from the Helmholtz-Zentrum Berlin (HZB) and the University of Virginia...
Novel highly efficient and brilliant gamma-ray source: Based on model calculations, physicists of the Max PIanck Institute for Nuclear Physics in Heidelberg propose a novel method for an efficient high-brilliance gamma-ray source. A giant collimated gamma-ray pulse is generated from the interaction of a dense ultra-relativistic electron beam with a thin solid conductor. Energetic gamma-rays are copiously produced as the electron beam splits into filaments while propagating across the conductor. The resulting gamma-ray energy and flux enable novel experiments in nuclear and fundamental physics.
The typical wavelength of light interacting with an object of the microcosm scales with the size of this object. For atoms, this ranges from visible light to...
13.04.2018 | Event News
12.04.2018 | Event News
09.04.2018 | Event News
24.04.2018 | Information Technology
24.04.2018 | Earth Sciences
24.04.2018 | Life Sciences