Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Healthy Parents Provide Clues to Survival of Young Haddock on Georges Bank

29.05.2008
Large fall phytoplankton bloom could control reproduction, future stock size

In 2003, haddock on Georges Bank experienced the largest baby boom ever documented for the stock, with an estimated 800 million new young fish entering the population. With typical annual averages of 50 to 100 million new fish in the last few decades, fisheries biologists have been puzzled by the huge increase and its ramifications for stock management. They have been looking for answers and may have found one - healthy adults.

In a study to be published in the June issue of the Canadian Journal of Fisheries and Aquatic Sciences, Dr. Kevin Friedland and colleagues from NOAA’s National Marine Fisheries Service and the University of Massachusetts suggest that the successful 2003 recruitment year is related to the fall phytoplankton bloom the year before spawning, and to the condition of the adult haddock. Phytoplankton, microscopic marine plants, form the basis of the ocean food web, and are the main source of food for many fish and other animals in the ocean. The fall 2002 bloom was significant, providing a larger than usual source of food for the ecosystem.

“Simply put, having more food to eat gives adult haddock a chance to get into better physical shape to reproduce healthy offspring with a higher chance of survival,” says Friedland, a research scientist at NOAA Fisheries’ Northeast Fisheries Science Center. “We reviewed the commonly applied factors that control recruitment, and found that the fall phytoplankton bloom the year before seems to link parental condition with a good recruitment. We call this new approach the parental condition hypothesis.”

The researchers analyzed various factors that control recruitment, from egg and larval retention, feeding conditions for larvae, size of juveniles in the fall and their estimated hatch dates, prey and time of spawning to circulation patterns and the timing and size of spring and fall phytoplankton blooms. They found that the fall phytoplankton bloom the year prior to spawning and its affect on the condition of adults to be the best supported hypothesis.

Their study suggests that the condition of the adult haddock not only leads to an improved chance to reproduce, but that the adults will produce more eggs of higher quality with higher fertilization rates. Those factors in turn will produce more abundant, larger and potentially better-conditioned offspring with a higher probability of survival to adulthood, which can significantly affect haddock stocks.

Georges Bank haddock have been heavily fished by domestic and foreign fleets over the past 50 years, with shifting patterns of fishery yieldsthat are largely dependent on successful recruitment events. The paradigm that processes affecting mortality during the early life stages determine recruitment has guided research on Georges Bank for decades, with many recent studies suggesting that the formation of each incoming year class of new fish is driven by differing sets of external environmental factors ranging from climate change patterns like the North Atlantic Oscillation to timing of spawning and the feeding environment.

Friedland and colleagues suggest a new paradigm, that the condition of parents affects egg size and fertilization success through the most difficult growth-mortality period early in the haddock life cycle. The bottom line: the number and quality of offspring is more important than the external environmental factors that occur after spawning.

“We need to be able to explain extreme recruitment events for species like haddock, where recruitment is typified by highly unusual circumstances like that in 2003,” Friedland says. “Factors that may be responsible for these large recruitments will help dictate how the haddock resource on Georges Bank is utilized and conserved. This new hypothesis needs to be tested, but it seems to be the only one that explains the 2003 record year class. If it proves true, the implications could be significant.”

NOAA Fisheries Service is dedicated to protecting and preserving our nation's living marine resources and their habitat through scientific research, management and enforcement. NOAA Fisheries Service provides effective stewardship of these resources for the benefit of the nation, supporting coastal communities that depend upon them, and helping to provide safe and healthy seafood to consumers and recreational opportunities for the American public.

The National Oceanic and Atmospheric Administration, an agency of the U.S. Commerce Department, is dedicated to enhancing economic security and national safety through the prediction and research of weather and climate-related events and information service delivery for transportation, and by providing environmental stewardship of our nation's coastal and marine resources. Through the emerging Global Earth Observation System of Systems (GEOSS), NOAA is working with its federal partners, more than 70 countries and the European Commission to develop a global monitoring network that is as integrated as the planet it observes, predicts and protects.

Shelley Dawicki | EurekAlert!
Further information:
http://www.noaa.gov

More articles from Ecology, The Environment and Conservation:

nachricht Successful calculation of human and natural influence on cloud formation
04.11.2016 | Goethe-Universität Frankfurt am Main

nachricht Invasive Insects Cost the World Billions Per Year
04.10.2016 | University of Adelaide

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: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

Im Focus: Molecules change shape when wet

Broadband rotational spectroscopy unravels structural reshaping of isolated molecules in the gas phase to accommodate water

In two recent publications in the Journal of Chemical Physics and in the Journal of Physical Chemistry Letters, researchers around Melanie Schnell from the Max...

Im Focus: Fraunhofer ISE Develops Highly Compact, High Frequency DC/DC Converter for Aviation

The efficiency of power electronic systems is not solely dependent on electrical efficiency but also on weight, for example, in mobile systems. When the weight of relevant components and devices in airplanes, for instance, is reduced, fuel savings can be achieved and correspondingly greenhouse gas emissions decreased. New materials and components based on gallium nitride (GaN) can help to reduce weight and increase the efficiency. With these new materials, power electronic switches can be operated at higher switching frequency, resulting in higher power density and lower material costs.

Researchers at the Fraunhofer Institute for Solar Energy Systems ISE together with partners have investigated how these materials can be used to make power...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

UTSA study describes new minimally invasive device to treat cancer and other illnesses

02.12.2016 | Medical Engineering

Plasma-zapping process could yield trans fat-free soybean oil product

02.12.2016 | Agricultural and Forestry Science

What do Netflix, Google and planetary systems have in common?

02.12.2016 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>