Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Are North Atlantic Right Whales Mating in the Gulf of Maine?

25.07.2013
Using data obtained during six years of regular aerial surveys and genetics data collected by a consortium of research groups, scientists have strengthened evidence pointing to the central Gulf of Maine as a mating ground for North Atlantic right whales, according to a study recently published online in the journal Endangered Species Research.

The North Atlantic right whale (Eubalaena glacialis) is one of the most endangered marine mammal species in the world and has been intensively studied for decades. Much has been learned about its habitat, behavior, and population demographics. But until now, there was little to indicate where these whales mated, a big missing piece in the puzzle of their life history.

"A high proportion of potential mates aggregated in the central Gulf of Maine between November and January, and these same individuals produced a calf a year later. We concluded that this is a pretty strong indication of a mating ground if the gestation period is 12 months," said Tim Cole, lead author and a biologist at the Woods Hole Laboratory of NOAA’s Northeast Fisheries Science Center (NEFSC).

Through aerial surveys, the researchers documented not only how many but also which right whales were present in the study area during 2002-2008. Individual animals were identified using a photo identification catalog maintained at the New England Aquarium that includes most of the adults in the population. Using genetic data gathered in other field work, known fathers seen in the surveys were identified, as were known mothers, who were identified by association with a calf.

The resulting analyses showed that the animals seen included a higher proportion of reproductively successful animals than were present in other areas that these whales used seasonally. The researchers further assumed a 12-month gestation period for North Atlantic right whales, similar to that estimated for the closely-related southern right whale (Eubalaena australis) by the South African whale biologist Dr. Peter Best.

How definitive is the study? Cole says that while it's a strong indicator, there could well be other mating areas, and its not clear how fixed the areas might be. In fact, since the study ended, fewer right whales have been observed in the area during what would be the mating period. The study also found a similar, if less dramatic, indication that Roseway Basin - an area south of Nova Scotia - may also serve as a mating ground.

"We are still seeing right whales in the central Gulf of Maine, just not in the same numbers. They are still out there, but where they all are is the big question. The decline is significant, so something appears to have changed," Cole said. "The good news is that calf production has been fairly good, with 22 calves born in 2011, 7 in 2012, and 20 this past winter. It will be interesting to see how many calves are born next year."

Most of the North Atlantic right whale population spends the spring and summer on feeding grounds off the northeastern U.S. and the Canadian Maritimes. In late fall and early winter, pregnant females migrate to waters off the southeastern U.S. to give birth. Mothers and calves are detected during intensive aerial surveys conducted from December through March off the coasts of Florida, Georgia, South Carolina, and North Carolina. Mothers and calves return to the northeast feeding grounds in the early spring, and the calves stay with their mothers for a year following birth.

Recovery of this endangered species depends on successful reproduction, but current reproductive rates for North Atlantic right whales are much lower than those for the recovering populations of southern right whales. The reasons for this are unknown, but may include a low level of genetic variability and /or inbreeding, disease, biotoxins, pollutants, food supply limitations, and habitat loss. Increased ocean noise from coastal development could also impact the species by triggering behavioral changes that negatively impact reproduction. Determining the right whale's conception period and mating grounds are important steps in learning about the factors that may be impairing reproduction.

In addition to Cole, study authors included Allison Glass Henry, Peter Duley and Richard Pace from NOAA's Northeast Fisheries Science Center; Philip Hamilton from the New England Aquarium; Bradley White from Trent University in Ontario, Canada; and Tim Frasier from St. Mary’s University in Halifax, Nova Scotia, Canada.

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.

NOAA’s mission is to understand and predict changes in the Earth's environment, from the depths of the ocean to the surface of the sun, and to conserve and manage our coastal and marine resources. Join us on Facebook, Twitter and our other social media channels.

Shelley Dawicki | EurekAlert!
Further information:
http://www.noaa.gov
http://www.nefsc.noaa.gov/press_release/2013/SciSpot/SS1308/

More articles from Ecology, The Environment and Conservation:

nachricht How fires are changing the tundra’s face
12.12.2017 | Gesellschaft für Ökologie e.V.

nachricht Using drones to estimate crop damage by wild boars
12.12.2017 | Gesellschaft für Ökologie e.V.

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: Long-lived storage of a photonic qubit for worldwide teleportation

MPQ scientists achieve long storage times for photonic quantum bits which break the lower bound for direct teleportation in a global quantum network.

Concerning the development of quantum memories for the realization of global quantum networks, scientists of the Quantum Dynamics Division led by Professor...

Im Focus: Electromagnetic water cloak eliminates drag and wake

Detailed calculations show water cloaks are feasible with today's technology

Researchers have developed a water cloaking concept based on electromagnetic forces that could eliminate an object's wake, greatly reducing its drag while...

Im Focus: Scientists channel graphene to understand filtration and ion transport into cells

Tiny pores at a cell's entryway act as miniature bouncers, letting in some electrically charged atoms--ions--but blocking others. Operating as exquisitely sensitive filters, these "ion channels" play a critical role in biological functions such as muscle contraction and the firing of brain cells.

To rapidly transport the right ions through the cell membrane, the tiny channels rely on a complex interplay between the ions and surrounding molecules,...

Im Focus: Towards data storage at the single molecule level

The miniaturization of the current technology of storage media is hindered by fundamental limits of quantum mechanics. A new approach consists in using so-called spin-crossover molecules as the smallest possible storage unit. Similar to normal hard drives, these special molecules can save information via their magnetic state. A research team from Kiel University has now managed to successfully place a new class of spin-crossover molecules onto a surface and to improve the molecule’s storage capacity. The storage density of conventional hard drives could therefore theoretically be increased by more than one hundred fold. The study has been published in the scientific journal Nano Letters.

Over the past few years, the building blocks of storage media have gotten ever smaller. But further miniaturization of the current technology is hindered by...

Im Focus: Successful Mechanical Testing of Nanowires

With innovative experiments, researchers at the Helmholtz-Zentrums Geesthacht and the Technical University Hamburg unravel why tiny metallic structures are extremely strong

Light-weight and simultaneously strong – porous metallic nanomaterials promise interesting applications as, for instance, for future aeroplanes with enhanced...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

AKL’18: The opportunities and challenges of digitalization in the laser industry

07.12.2017 | Event News

 
Latest News

A whole-body approach to understanding chemosensory cells

13.12.2017 | Health and Medicine

Water without windows: Capturing water vapor inside an electron microscope

13.12.2017 | Physics and Astronomy

Cellular Self-Digestion Process Triggers Autoimmune Disease

13.12.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>