Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Non-native marine species' spread, impact explained by time since introduction

11.08.2015

The time since the introduction of a non-native marine species best explains its global range, according to new research by an international team of scientists led by University of Georgia ecologist James E. Byers. The study, published in the open access journal Nature Scientific Reports, also contains a warning: The vast majority of marine invaders have not yet finished spreading.

Invasion by non-native species is a worldwide problem that causes billions of dollars of damage annually--more than $120 billion in the U.S. alone, according to a 2005 study cited by the U.S. Fish and Wildlife Service. Preventing future invasions, and mitigating the impacts of those already underway, is a critical goal, Byers said.


The European green crab, Carcinus maenas, is found throughout New England, the Canadian Maritimes, the west coast of North America from California to British Columbia as well as South Africa, New Zealand and Tasmania. It has large impacts on shellfish stocks and can reach high densities. It's been present in New England for almost 200 years.

Credit: D. Hazerli

Effective defenses against species invasions depend on understanding the mechanisms driving them. Control strategies have typically been based on key characteristics of the non-native species and the environments they're invading. For marine invaders, these include traits like mobility, maximum body size and larvae dispersal, and environmental conditions such as salinity, temperature and strength of ocean currents. Control strategies differ depending on which traits or environmental conditions are thought to be the main drivers of invasion.

Despite numerous studies, there has not been scientific consensus on which of these factors are most important.

While attending an invited workshop for experts in marine invasions in Sydney, Australia, in 2012, Byers and his colleagues conceived the idea for a comprehensive analysis to determine which variables were the best predictors of an invader's spread.

"This paper arose because we saw that we could gather data on a large number of species," Byers said. "Data clearing houses have gotten much better at recording species occurrence data."

Byers and his co-authors focused on marine benthic invertebrates--creatures such as crabs and barnacles that live on the ocean floor--that are non-native to the U.S., Australia or New Zealand, because those countries have the most comprehensive records.

They combed through national port surveys, invasive species databases and scientific literature, compiling information on as many of the animals' physical characteristics as possible, as well as environmental conditions of areas outside their native ranges. They also included records of each species' first introduction anywhere in the world. In all, they found 138 species with enough information to include in their analysis.

They then created a model to test which of the variables--species' traits, environmental conditions or time since introduction--did the best job of predicting the global ranges of those non-native species.

Time since introduction proved to be the most useful measurement.

"The fact that the physical variables didn't do such a good job of helping to predict range surprised us," Byers said. "Those variables must be important, but, in hindsight, if species are only occupying a fraction of their total potential non-native range, it does make sense that the physical variables would not yet work well."

He explained that a newly introduced species needs time to fully occupy its potential range in a new region.

"There may be plenty of places suitable for it to live in that novel region, but it just hasn't had time to spread there yet," he said. "Because we don't yet see the fully realized extent, it is hard to characterize a species' tolerances and limits that would otherwise control range size."

Byers said the study's results could nevertheless provide some guidance for managers.

"There is a lot of emphasis in invasion ecology in looking for predictive factors that can tell us what species or what habitats may be most at risk," Byers said. "Our analysis says at a large scale this may be hard to come up with, at least at this point in time before we are able to analyze the fully realized ranges of a sufficient number of invaders. Thus instead, we advocate careful vigilance at sites receiving the greatest number of potential invasive species delivery vectors, like ships with ballast water or imports for aquaculture."

###

The paper is available online at http://www.nature.com/srep/2015/150731/srep12436/full/srep12436.html.

The study's co-authors are Rachel S. Smith, UGA Odum School of Ecology; James M. Pringle, University of New Hampshire; Graeme F. Clark, Paul E. Gribben and Emma L. Johnston, University of New South Wales, Australia; Chad L. Hewitt, University of Waikato, New Zealand; Graeme J. Inglis, National Institute of Water and Atmospheric Research, New Zealand; Gregory M. Ruiz, Smithsonian Environmental Research Center; John J. Stachowicz, University of California, Davis; and Melanie J. Bishop, Macquarie University, Australia.

Funding was provided by Macquarie University, the University of New South Wales, the National Science Foundation, the New Zealand Ministry for Primary Industries and National Institute of Water and Atmospheric Research, the National Sea Grant Program and the Smithsonian Institution.

Media Contact

James E. Byers
jebyers@uga.edu
706-583-0012

 @universityofga

http://www.uga.edu 

James E. Byers | EurekAlert!

More articles from Ecology, The Environment and Conservation:

nachricht Scientists team up on study to save endangered African penguins
16.11.2017 | Florida Atlantic University

nachricht Climate change: Urban trees are growing faster worldwide
13.11.2017 | Technische Universität München

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Frictional Heat Powers Hydrothermal Activity on Enceladus

Computer simulation shows how the icy moon heats water in a porous rock core

Heat from the friction of rocks caused by tidal forces could be the “engine” for the hydrothermal activity on Saturn's moon Enceladus. This presupposes that...

Im Focus: Nanoparticles help with malaria diagnosis – new rapid test in development

The WHO reports an estimated 429,000 malaria deaths each year. The disease mostly affects tropical and subtropical regions and in particular the African continent. The Fraunhofer Institute for Silicate Research ISC teamed up with the Fraunhofer Institute for Molecular Biology and Applied Ecology IME and the Institute of Tropical Medicine at the University of Tübingen for a new test method to detect malaria parasites in blood. The idea of the research project “NanoFRET” is to develop a highly sensitive and reliable rapid diagnostic test so that patient treatment can begin as early as possible.

Malaria is caused by parasites transmitted by mosquito bite. The most dangerous form of malaria is malaria tropica. Left untreated, it is fatal in most cases....

Im Focus: A “cosmic snake” reveals the structure of remote galaxies

The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.

Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...

Im Focus: Visual intelligence is not the same as IQ

Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.

That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...

Im Focus: Novel Nano-CT device creates high-resolution 3D-X-rays of tiny velvet worm legs

Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.

During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Ecology Across Borders: International conference brings together 1,500 ecologists

15.11.2017 | Event News

Road into laboratory: Users discuss biaxial fatigue-testing for car and truck wheel

15.11.2017 | Event News

#Berlin5GWeek: The right network for Industry 4.0

30.10.2017 | Event News

 
Latest News

Desert ants cannot be fooled

23.11.2017 | Life Sciences

By saving cost and energy, the lighting revolution may increase light pollution

23.11.2017 | Earth Sciences

Retreating permafrost coasts threaten the fragile Arctic environment

23.11.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>