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!
How does the loss of species alter ecosystems?
18.05.2017 | Deutsches Zentrum für integrative Biodiversitätsforschung (iDiv) Halle-Jena-Leipzig
Excess diesel emissions bring global health & environmental impacts
16.05.2017 | International Institute for Applied Systems Analysis (IIASA)
The world's highest gain high power laser amplifier - by many orders of magnitude - has been developed in research led at the University of Strathclyde.
The researchers demonstrated the feasibility of using plasma to amplify short laser pulses of picojoule-level energy up to 100 millijoules, which is a 'gain'...
Staphylococcus aureus is a feared pathogen (MRSA, multi-resistant S. aureus) due to frequent resistances against many antibiotics, especially in hospital infections. Researchers at the Paul-Ehrlich-Institut have identified immunological processes that prevent a successful immune response directed against the pathogenic agent. The delivery of bacterial proteins with RNA adjuvant or messenger RNA (mRNA) into immune cells allows the re-direction of the immune response towards an active defense against S. aureus. This could be of significant importance for the development of an effective vaccine. PLOS Pathogens has published these research results online on 25 May 2017.
Staphylococcus aureus (S. aureus) is a bacterium that colonizes by far more than half of the skin and the mucosa of adults, usually without causing infections....
Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.
The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....
An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.
We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...
Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.
Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...
24.05.2017 | Event News
23.05.2017 | Event News
22.05.2017 | Event News
29.05.2017 | Physics and Astronomy
29.05.2017 | Physics and Astronomy
29.05.2017 | Earth Sciences