NATURALIST'S 



NOTEBOOK 



"In this stranding, we had full adults, older 

 animals, calves and a few pregnant females," he 

 adds. "There was a full range of age structure 

 involved." 



Hohn cites an average of about 150 stand- 

 ings per year, including whales and dolphins. 

 "Most are dead or die after beaching," she says. 



If a stranding involves two or more 

 animals, it's called a mass stranding. "We get 

 several mass standings a year," Hohn adds. 



The UNCW Marine Mammal Stranding 

 Program report says North Carolina has the 

 highest species diversity of standings along 

 the Atlantic Coast. "All but two species known 

 to occur in the North Atlantic have stranded on 

 North Carolina beaches." 



The state's coastal environment may be 

 a factor in the number and diversity of marine 

 mammal standings. 



"The physical characteristics of the 

 shoreline [off the coast of North Carolina] can 



facilitate standings," says Harms. "We have a 

 shallow, sloping shoreline and it is acoustically 

 difficult to interpret." 



"Whale sonar may not pick up the 

 shoreline," he explains. "This is why the Navy 

 wants to train there — because it is difficult to 

 interpret." 



"We have not seen many mass standings 

 of this size — and that's been a blessing for us 

 in North Carolina," Harms adds. "Our 33 was 

 about all we could handle." 



PILOT WHALE PODS 



"Pilot whales are very social," Harms says 

 of the animals known to organize themselves 

 into pods with hundreds of individuals. An 

 average pod contains 20 to 90 pilot whales. 



A large pod is a not only a social structure, 

 but also a useful defense mechanism. "They can 

 coordinate hunts and concentrate their prey," 

 Harms says. "They also have a mutual defense." 



But the social bonds also can be 

 detrimental. "Pilot whales are social, and it 

 promotes the largest number of standings," 

 Harms explains. "They often stay together when 

 it is not to their advantage." 



Sometimes the whales follow each other 

 to their deaths upon beaches. "If you follow 

 the behavior stranding theory, they may follow 

 a leader sometimes that is not 100 percent 

 healthy," he adds. "When one pilot whale is in 

 distress or sick, the pod does not abandon that 

 member. Sometimes they are led to shallow 

 waters." 



In some cases, members of the stranding 

 network arrive in time to rescue the animals. 

 Other times, the whales must be euthanized 

 because they are too distressed from being out 

 of the water for too long. 



But even when part of a pod is rescued, 

 those animals often wait offshore until the last 

 live member of the pod is back in the water. □ 



Pilot Whale Fast Facts 



Scientific name: Globicephala melaena (long-finned) and Globicephala macrorhynchus (short-finned) Life Span: Average 40 to 50 years 

 Males: Average of 18 feet long and a maximum of 6,500 pounds Females: Average of 12 feet long and a maximum of 2,600 pounds 



Pilot whales travel in "pods," sometimes only six animals, other times 

 more than 100. 



■ They have dark bodies — mostly black and gray — with a lighter 

 underbelly. 



Pilot whales have rounded heads, slight beaks and an up-curved mouth 

 line. Sometimes the head protrudes up to four inches over the lower jaw. 

 Pilot whales have 40 to 48 teeth that are used for catching and 

 grasping. Other dolphin species have about 120 teeth. 



■ The shape of a pilot whale's head varies depending on age and sex. 

 Adult males have the roundest heads. 



Globicephala melaena 



Pilot whales eat about 5 percent of their body weight each day. 

 * The peak mating seasons are spring and early summer. Calves are 



usually born in the late summer after a 1 6-month gestation period. 

 ■ Females in the wild sometimes live 65 years. 



Short-finned pilot whales maintain average swimming speeds of 5 



miles per hour. 



8 For more information on pilot whales, check out Pdiode Island Sea 

 Grant's Guide to Marine Mammals & Turtles of the U.S. Atlantic & 

 Gulf of Mexico. To order the book: go online to http://seagrant.gso. 

 uri.edu/ and click on "Bookstore." 



Coastwatch I Autumn 2006 I www.ncseagrant.org 29 



