Featured Research

from universities, journals, and other organizations

Fish larvae find the reef by orienting: The earlier the better

Date:
April 23, 2012
Source:
University of Miami Rosenstiel School of Marine & Atmospheric Science
Summary:
For the first time, a numerical study incorporates horizontal larval fish navigation skills into realistic 3D flow fields, creating a powerful tool that spells out how larvae use environmental cues to find their way back to the reef after being out on the open ocean. This model can be used for a wide variety of marine species.

Damselfish larvae (Chromis atripectoralis) swimming freely in the open ocean, all in the same direction, off Lizard Island, Australia.
Credit: Ricardo Paris

The behavior of marine larvae is central to fully understanding and modeling the pelagic (open ocean) stage for many coastal organisms. For the first time, a numerical study conducted by the University of Miami (UM) incorporates horizontal larval fish navigation skills into realistic 3D flow fields, creating a powerful tool that spells out how larvae use environmental cues to find their way back to the reef after being out on the open ocean. The new model uses reliable larval swimming speeds and vertical migration, known life history traits and spawning time to create realistic scenarios that can be studied in detail.

In an article entitled: "Orientation behavior in fish larvae: A missing piece to Hjort's critical period hypothesis" that appears in the latest edition of the Journal of Theoretical Biology, scientists Erica Staaterman, Claire Paris and Judith Helgers demonstrate that despite very low swimming speeds -- approximately a few centimeters per second -- orientation behavior during early stages is critical to bringing larvae back to the juvenile habitat. The research team shows that baby reef-fish must possess, as early as possible, the ability to sense cues radiating from the habitat that help them to navigate and survive the pelagic phase.

The team used Hjort's "critical period" hypothesis, which says that fish recruitment variability is driven by the fate of the earliest larval stages, and that food and "aberrant drift" are the main factors contributing to the survivorship during this early phase. According to this hypothesis, the proportion of survivors during this "critical" larval phase is carried over throughout the entire life history of the fish's population.

"Orientation during the "critical period" appears to have remarkable demographic consequences," said UM Applied Marine Physics Professor Paris. "Larvae need to orient themselves soon after hatching to increase their chance to find any reef or to come back to their home reef. This notion of 'larval homing behavior' is a new concept, but it makes sense when compared to other essential larval developmental traits such as first feeding and swimming. If early fish larvae can sense their way home, we were certainly missing an important component in current bio-physical models that would change predictions of marine population connectivity."

"Using this model we can add to Hjorts' hypothesis that 'behavior' is a main factor contributing to the survivorship of the larvae, as well," said Staaterman, a Ph.D. student at UM. "We have discovered that recruitment of reef-fish is linked to signals perceived by the pelagic larvae; if the signals disappear or weaken, larvae can get lost. Therefore, the health of the coral reef and its cues is not only critical to the adult reef-fishes, but it is also essential to the survivorship of their pelagic larvae."

This study also shows the importance of the health of the habitat, even in complex coastal circulation with eddies and counter-currents: The stronger the cue information radiating from the surrounding habitat, the higher the survival rate of the larvae.

The flexible numerical tool that was developed through this study will allow scientists to set up hypotheses about both the nature of the cues and the larval behavior of a wide variety of marine species. This knowledge will allow us to better understand the enigmatic ecological "black box" of the pelagic larval phase, and help communities to better manage marine resources.

"These kind of studies, where the paths of millions of fish larvae are simulated in a model ocean, are really only feasible with the newest generation of numerical models," said Helgers, a computer scientist who contributed to the model algorithm which is designed to answer questions on the interaction of larvae with ocean currents. "The model we have built is fast and reliable, which allows us to perform the complex computations required to track the larvae in a high resolution model ocean."

"The outcomes of this study should serve to re-focus research on basic understanding of what larvae are capable of sensing, how they use their capabilities in the pelagic environment, and finally on the sequential importance of navigational cues needed for survival," added Paris.


Story Source:

The above story is based on materials provided by University of Miami Rosenstiel School of Marine & Atmospheric Science. Note: Materials may be edited for content and length.


Journal Reference:

  1. Erica Staaterman, Claire B. Paris, Judith Helgers. Orientation behavior in fish larvae: A missing piece to Hjort's critical period hypothesis. Journal of Theoretical Biology, 2012; DOI: 10.1016/j.jtbi.2012.03.016

Cite This Page:

University of Miami Rosenstiel School of Marine & Atmospheric Science. "Fish larvae find the reef by orienting: The earlier the better." ScienceDaily. ScienceDaily, 23 April 2012. <www.sciencedaily.com/releases/2012/04/120423132013.htm>.
University of Miami Rosenstiel School of Marine & Atmospheric Science. (2012, April 23). Fish larvae find the reef by orienting: The earlier the better. ScienceDaily. Retrieved July 30, 2014 from www.sciencedaily.com/releases/2012/04/120423132013.htm
University of Miami Rosenstiel School of Marine & Atmospheric Science. "Fish larvae find the reef by orienting: The earlier the better." ScienceDaily. www.sciencedaily.com/releases/2012/04/120423132013.htm (accessed July 30, 2014).

Share This




More Plants & Animals News

Wednesday, July 30, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Raw: Otters Enjoy Water Slides at Japan Zoo

Raw: Otters Enjoy Water Slides at Japan Zoo

AP (July 30, 2014) River otters were hitting the water slides to beat the summer heatwave on Wednesday at Ichikawa City's Zoological and Botanical Garden. (July 30) Video provided by AP
Powered by NewsLook.com
In Virginia, the Rise of a New Space Coast

In Virginia, the Rise of a New Space Coast

AP (July 30, 2014) Every summer, tourists make the pilgrimage to Chincoteague Island, Va. to see wild ponies cross the Assateague Channel. But, it's the rockets sending to supplies to the International Space Station that are making this a year-round destination. (July 30) Video provided by AP
Powered by NewsLook.com
Rodents Rampant in Gardens Around Louvre

Rodents Rampant in Gardens Around Louvre

AP (July 29, 2014) Food scraps and other items left on the grounds by picnickers brings unwelcome visitors to the grounds of the world famous and popular Louvre Museum in Paris. (July 29) Video provided by AP
Powered by NewsLook.com
Jane Goodall Warns Great Apes Face Extinction

Jane Goodall Warns Great Apes Face Extinction

AFP (July 29, 2014) The world's great apes face extinction within decades, renowned chimpanzee expert Jane Goodall warned Tuesday in a call to arms to ensure man's closest relatives are not wiped out. Duration: 00:58 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins