Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Pioneer Study Examines Declining Coral Reef Health Due to Pesticides/Sea Surface Temperatures


The declining health of coral reefs is intensifying worldwide at an alarming rate, due to the combined effects of land-based sources of pollution and climate change. Despite the persistent use of mosquito-control pesticides in populated coastal areas, studies examining the survival and physiological impacts on the early life stages of foundation species, like corals, are limited.

In order to better understand the combined effects of mosquito pesticides and rising sea-surface temperatures, Dr. Cliff Ross, an associate professor of biology at the University of North Florida, along with scientists from Mote Marine Laboratory, exposed larvae from the coral, Porites astreoides, to selected concentrations of pesticides and temperatures.

Image of Porites astreoides as an adult on a reef.

In this pioneer study, recently published in Ecotoxicology, Ross and his colleagues—Kevin Olsen, Michael Henry and Dr. Richard Pierce—uncovered that this particular coral larvae were shown to have a moderate degree of resistance against short-term exposure to ecologically relevant concentrations of pesticides, even in the presence of elevated temperature.

“The significance of this work is that coral reefs across the globe are declining at an alarming rate due to climate change (warming ocean temperatures) and pollution. If baby corals don’t survive exposure to these stressors, then you won’t have adults, which are needed to reproduce and maintain the populations,” said Ross, who is focusing his current research at UNF on understanding the effects of climate change and environmental stressors on marine organisms, such as corals and sea grasses.

One big issue in the Florida Keys and many other coastal environments, Ross noted, is the use of mosquito-control pesticides. The Florida Keys relies heavily upon tourism. Unfortunately, the same beautiful habitat is conducive towards mosquito growth. According to Ross, the Florida Keys Mosquito Control district does an excellent job controlling mosquito populations by applying pesticides. Unfortunately, he said, some of these pesticides can inadvertently end up in the ocean and have a negative effect on marine life.

What kind of possible negative effects? In order to better understand the combined effects of mosquito pesticides and rising sea-surface temperatures, Ross collected and exposed coral larvae to selected concentrations of two major mosquito pesticide ingredients, naled and permethrin, and seawater elevated to +3.5 degrees Celsius. After 18 to 20 hours of exposure, larvae subjected to high naled concentrations had significantly reduced survivorship compared to controls. These effects weren’t detected in the presence of permethrin or elevated temperature.

Additionally, larval settlement, post-settlement survival and bleaching weren’t impacted by any treatment. To evaluate the sub-lethal stress response of larvae, several cellular and molecular assays were run. These assays determine if the larvae are stressed, much like a human blood test. The molecular responses to pesticide exposure were variable and contingent upon pesticide type, as well as the specific biomarker being employed.

In some cases, such as with the protein carbonylation and catalase gene expression, the effects of naled exposure and temperature were interactive. In other cases, pesticide exposure failed to induce any sub-lethal stress response.

Overall, these results demonstrate that Porites astreoides larvae have a moderate degree of resistance against short-term exposure to ecologically relevant concentrations of pesticides, even in the presence of elevated temperature. However, Ross notes much more work is needed on this topic, since there are many different types of environmental stressors that can interact with pesticides to cause damage to corals.

“With the onset of increasing stress to coral reefs, via direct human activities, or indirectly through effects associated with climate change, a more complete understanding of how stress impacts corals is essential,” said Ross. “In particular, as the use of pesticides increases in coastal communities there is a need to investigate the negative effects on early life stages of foundation species like corals.”

The full study, to be published in the February 2015 issue, can be found at 

The University of North Florida in Jacksonville is a nationally ranked university located on an environmentally beautiful campus, offers students who are dedicated to enriching the lives of others the opportunity to build their own futures through a well-rounded education.

Contact Information
Joanna Norris
Public Relations Director
Phone: 904-620-2102

Joanna Norris | newswise
Further information:

More articles from Ecology, The Environment and Conservation:

nachricht Dispersal of Fish Eggs by Water Birds – Just a Myth?
19.02.2018 | Universität Basel

nachricht Removing fossil fuel subsidies will not reduce CO2 emissions as much as hoped
08.02.2018 | International Institute for Applied Systems Analysis (IIASA)

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: Locomotion control with photopigments

Researchers from Göttingen University discover additional function of opsins

Animal photoreceptors capture light with photopigments. Researchers from the University of Göttingen have now discovered that these photopigments fulfill an...

Im Focus: Surveying the Arctic: Tracking down carbon particles

Researchers embark on aerial campaign over Northeast Greenland

On 15 March, the AWI research aeroplane Polar 5 will depart for Greenland. Concentrating on the furthest northeast region of the island, an international team...

Im Focus: Unique Insights into the Antarctic Ice Shelf System

Data collected on ocean-ice interactions in the little-researched regions of the far south

The world’s second-largest ice shelf was the destination for a Polarstern expedition that ended in Punta Arenas, Chile on 14th March 2018. Oceanographers from...

Im Focus: ILA 2018: Laser alternative to hexavalent chromium coating

At the 2018 ILA Berlin Air Show from April 25–29, the Fraunhofer Institute for Laser Technology ILT is showcasing extreme high-speed Laser Material Deposition (EHLA): A video documents how for metal components that are highly loaded, EHLA has already proved itself as an alternative to hard chrome plating, which is now allowed only under special conditions.

When the EU restricted the use of hexavalent chromium compounds to special applications requiring authorization, the move prompted a rethink in the surface...

Im Focus: Radar for navigation support from autonomous flying drones

At the ILA Berlin, hall 4, booth 202, Fraunhofer FHR will present two radar sensors for navigation support of drones. The sensors are valuable components in the implementation of autonomous flying drones: they function as obstacle detectors to prevent collisions. Radar sensors also operate reliably in restricted visibility, e.g. in foggy or dusty conditions. Due to their ability to measure distances with high precision, the radar sensors can also be used as altimeters when other sources of information such as barometers or GPS are not available or cannot operate optimally.

Drones play an increasingly important role in the area of logistics and services. Well-known logistic companies place great hope in these compact, aerial...

All Focus news of the innovation-report >>>



Industry & Economy
Event News

Ultrafast Wireless and Chip Design at the DATE Conference in Dresden

16.03.2018 | Event News

International Tinnitus Conference of the Tinnitus Research Initiative in Regensburg

13.03.2018 | Event News

International Virtual Reality Conference “IEEE VR 2018” comes to Reutlingen, Germany

08.03.2018 | Event News

Latest News

Development and Fast Analysis of 3D Printed HF Components

19.03.2018 | Trade Fair News

In monogamous species, a compatible partner is more important than an ornamented one

19.03.2018 | Life Sciences

Signaling Pathways to the Nucleus

19.03.2018 | Life Sciences

Science & Research
Overview of more VideoLinks >>>