Featured Research

from universities, journals, and other organizations

Are North Atlantic right whales mating in the Gulf of Maine?

Date:
July 24, 2013
Source:
NOAA Northeast Fisheries Science Center
Summary:
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 new study.

Surface Active Groups, or SAGs, are considered a reproductive behavior, but may also be a social activity among right whales.
Credit: Cynthia Christman, NOAA

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.


Story Source:

The above story is based on materials provided by NOAA Northeast Fisheries Science Center. Note: Materials may be edited for content and length.


Journal Reference:

  1. TVN Cole, P Hamilton, AG Henry, P Duley, RM Pace, BN White, T Frasier. Evidence of a North Atlantic right whale Eubalaena glacialis mating ground. Endangered Species Research, 2013; 21 (1): 55 DOI: 10.3354/esr00507

Cite This Page:

NOAA Northeast Fisheries Science Center. "Are North Atlantic right whales mating in the Gulf of Maine?." ScienceDaily. ScienceDaily, 24 July 2013. <www.sciencedaily.com/releases/2013/07/130724200514.htm>.
NOAA Northeast Fisheries Science Center. (2013, July 24). Are North Atlantic right whales mating in the Gulf of Maine?. ScienceDaily. Retrieved October 23, 2014 from www.sciencedaily.com/releases/2013/07/130724200514.htm
NOAA Northeast Fisheries Science Center. "Are North Atlantic right whales mating in the Gulf of Maine?." ScienceDaily. www.sciencedaily.com/releases/2013/07/130724200514.htm (accessed October 23, 2014).

Share This



More Plants & Animals News

Thursday, October 23, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Working Mother DIY: Pumpkin Pom-Pom

Working Mother DIY: Pumpkin Pom-Pom

Working Mother (Oct. 22, 2014) How to make a pumpkin pom-pom. Video provided by Working Mother
Powered by NewsLook.com
San Diego Zoo's White Rhinos Provide Hope for the Critically Endangered Species

San Diego Zoo's White Rhinos Provide Hope for the Critically Endangered Species

Reuters - Light News Video Online (Oct. 22, 2014) The pair of rare white northern rhinos bring hope for their species as only six remain in the world. Elly Park reports. Video provided by Reuters
Powered by NewsLook.com
Raw: Bear Cub Strolls Through Oregon Drug Store

Raw: Bear Cub Strolls Through Oregon Drug Store

AP (Oct. 22, 2014) Shoppers at an Oregon drug store were surprised by a bear cub scurrying down the aisles this past weekend. (Oct. 22) Video provided by AP
Powered by NewsLook.com
Family Pleads for Pet Pig to Stay at Home

Family Pleads for Pet Pig to Stay at Home

AP (Oct. 22, 2014) The Johnson family lost their battle with the Chesterfield County, Virginia Planning Commission to allow Tucker, their pet pig, to stay in their home, but refuse to let the board keep Tucker away. (Oct. 22) Video provided by AP
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:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

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