Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Ocean heat content reveals secrets of fish migration behaviors

22.10.2015

Study uses hurricane forecasting tool to show fishes affinity for ocean fronts and eddies

Researchers at the University of Miami (UM) Rosenstiel School of Marine and Atmospheric Science developed a new method to estimate fish movements using ocean heat content images, a dataset commonly used in hurricane intensity forecasting.


This image shows front and eddy utilization in the Gulf of Mexico by pelagic fishes revealed by ocean heat content: (a) a yellowfin tuna (Thunnus albacares); and, (b) an Atlantic sailfish. OHC maps are based on calculating thermal energy from the depths of the 20°C isotherm.

Credit: Jiangang Luo, UM Rosenstiel School of Marine and Atmospheric Science

With Atlantic tarpon as the messenger, this is the first study to quantitatively show that large migratory fishes, such as yellowfin and bluefin tunas, blue and white marlin, and sailfish have affinities for ocean fronts and eddies.

"Ocean heat content data revealed detailed movements of fishes that were not readily apparent using surface temperature data," said Jerald S. Ault, UM Rosenstiel School professor of marine biology and ecology. "This offers a powerful new approach to study how fish interact with dynamic water features relatively common in the ocean."

Ocean heat content (OHC) relative to the 26°C isotherm, a measure of heat stored in the upper surface layers of the ocean, has been used for more than four decades by scientists to help predict hurricane intensity. Over the past two decades, OHC has been monitored daily using satellite fields and in-situ data that provide basin-scale variability for both weather and climate studies.

In addition to providing the OHC for forecasting, these previous studies showed OHC images reveal dynamic ocean features, such as fronts and eddies, in the ocean better than just using standard techniques (e.g., sea surface temperature), especially during the summer months.

The researchers compared data on fish movements obtained from pop-up satellite tags affixed to the highly migratory fish alongside maps of the heat stored in the upper ocean. "Using an advanced optimization algorithm and OHC maps, we developed a method to greatly improve geolocation accuracy and refine fish movement tracks derived from satellite tags," said Jiangang Luo, lead author and UM scientist at the Tarpon and Bonefish Research Center. The analysis revealed that fish commonly swim along the boundaries of water features in the ocean, such as fronts, like the Florida and Loop Current and their complex eddy fields.

"Using the OHC approach in a new way offers an unprecedented view of how these animals move with currents and eddies in the ocean," said Nick Shay, UM Rosenstiel School professor of ocean sciences. "Our study provides a more detailed picture of the ocean ecosystem as an entity."

In one 109-day analysis, the researchers documented a yellowfin tuna move along a weak front off the Mississippi River before reaching an eddy centered in the Gulf of Mexico. In separate analysis, a yellowfin tuna swam around the periphery of the same eddy many times over a 20-day period, rarely passing over it.

Eddies are swirling masses of water that have been shed from strong ocean current fronts, and pump nutrient-rich water to the surface. Fronts are a type of current created at a boundary between two distinct water masses with differing physical properties, such as different temperatures, salinities. In the Gulf of Mexico, warm eddies are often shed from the Loop Current in the summer months causing a rapid intensification of hurricanes (e.g., Katrina) as they pass over it.

"Our new method shows that hurricanes and highly migratory fish share at least one common oceanographic interest - warm swirling ocean eddies," said Ault.

###

The study, titled "Ocean Heat Content Reveals Secrets of Fish Migration," was published in the Oct. 20 issue of the journal PLOS ONE. The study's authors include: Jiangang Luo, Jerald S. Ault, Lynn "Nick" Shay of the UM Rosenstiel School; John P. Hoolihan from the Cooperative Institute for Marine and Atmospheric Science at the University of Miami; Eric D. Prince and Craig A. Brown from the NOAA Southeast Fisheries Science Center; and Jay R. Rooker from Texas A&M University. The work was supported by grants from the Bonefish and Tarpon Trust, the Robertson Foundation, National Science Foundation, McDaniel Charitable Foundation, The Billfish Foundation, Adopt-A-Billfish Program and the National Oceanic and Atmospheric Administration (NOAA).

The study can be accessed on line here:

http://www.plosone.org/article/fetchObject.action?uri=info:doi/10.1371/journal.pone.0141101&representation=PDF

A video of a migration can be seen at:

https://youtu.be/-AmUKikPLuc

About the University of Miami's Rosenstiel School

The University of Miami is one of the largest private research institutions in the southeastern United States. The University's mission is to provide quality education, attract and retain outstanding students, support the faculty and their research, and build an endowment for University initiatives. Founded in the 1940's, the Rosenstiel School of Marine & Atmospheric Science has grown into one of the world's premier marine and atmospheric research institutions. Offering dynamic interdisciplinary academics, the Rosenstiel School is dedicated to helping communities to better understand the planet, participating in the establishment of environmental policies, and aiding in the improvement of society and quality of life. For more information, visit: http://www.rsmas.miami.edu.

Diana Udel | EurekAlert!

More articles from Life Sciences:

nachricht Mass spectrometry sheds new light on thallium poisoning cold case
14.12.2018 | University of Maryland

nachricht Protein involved in nematode stress response identified
14.12.2018 | University of Illinois College of Agricultural, Consumer and Environmental Sciences

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Data use draining your battery? Tiny device to speed up memory while also saving power

The more objects we make "smart," from watches to entire buildings, the greater the need for these devices to store and retrieve massive amounts of data quickly without consuming too much power.

Millions of new memory cells could be part of a computer chip and provide that speed and energy savings, thanks to the discovery of a previously unobserved...

Im Focus: An energy-efficient way to stay warm: Sew high-tech heating patches to your clothes

Personal patches could reduce energy waste in buildings, Rutgers-led study says

What if, instead of turning up the thermostat, you could warm up with high-tech, flexible patches sewn into your clothes - while significantly reducing your...

Im Focus: Lethal combination: Drug cocktail turns off the juice to cancer cells

A widely used diabetes medication combined with an antihypertensive drug specifically inhibits tumor growth – this was discovered by researchers from the University of Basel’s Biozentrum two years ago. In a follow-up study, recently published in “Cell Reports”, the scientists report that this drug cocktail induces cancer cell death by switching off their energy supply.

The widely used anti-diabetes drug metformin not only reduces blood sugar but also has an anti-cancer effect. However, the metformin dose commonly used in the...

Im Focus: New Foldable Drone Flies through Narrow Holes in Rescue Missions

A research team from the University of Zurich has developed a new drone that can retract its propeller arms in flight and make itself small to fit through narrow gaps and holes. This is particularly useful when searching for victims of natural disasters.

Inspecting a damaged building after an earthquake or during a fire is exactly the kind of job that human rescuers would like drones to do for them. A flying...

Im Focus: Topological material switched off and on for the first time

Key advance for future topological transistors

Over the last decade, there has been much excitement about the discovery, recognised by the Nobel Prize in Physics only two years ago, that there are two types...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

ICTM Conference 2019: Digitization emerges as an engineering trend for turbomachinery construction

12.12.2018 | Event News

New Plastics Economy Investor Forum - Meeting Point for Innovations

10.12.2018 | Event News

EGU 2019 meeting: Media registration now open

06.12.2018 | Event News

 
Latest News

Data use draining your battery? Tiny device to speed up memory while also saving power

14.12.2018 | Power and Electrical Engineering

Tangled magnetic fields power cosmic particle accelerators

14.12.2018 | Physics and Astronomy

In search of missing worlds, Hubble finds a fast evaporating exoplanet

14.12.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>