Thursday, November 11, 2010

Who Do They Kill and How Many?

 Taiji in 08-09 had a total quota of 2,393 dolphins, we do not know the actual numbers taken but here is a break down of the types of dolphins killed there.

Pacific White-Sided Dolphin (Lagenorhynchus obliquidens)

2008-09 Quota = 134

Pacific white-sided dolphins are extremely playful and highly social animals. Schools of thousands of Pacific white-sided dolphins are occasionally observed, but group size generally ranges from 10-100 animals. They are often observed "bow riding" and doing acrobatic somersaults. This species commonly associates with other cetaceans, such as Northern right whale dolphins and Risso's dolphins.
They prey on squid and small schooling fish such as capelin, sardines, and herring. This species is capable of diving more than 6 minutes to feed. They have small conical teeth that are helpful in grasping their prey. When feeding during the day, they can be seen working together as a group to herd schools of fish.
Pacific white-sided dolphins reach sexual maturity around 7-10 years of age around lengths of 5.5-6 ft (1.7-1.8 m). Gestation lasts for 12 months with calves being born in the summer months. Calves weigh approximately 30 pounds (15 kg) and are about 2.5-4 feet (1-1.2 m) in length. Females give birth less than every other year.

Striped Dolphin (Stenella coeruleoalba)

 2008-09 Quota = 450

Striped dolphins are usually found in tight, cohesive groups averaging between 25 and 100 individuals, but have been occasionally seen in larger groups of up to several hundred and even thousands of animals. Within these schools there is a complex system of individuals that may be organized by age, sex, and breeding status. They rarely associate with other species of whales, dolphins, and seabirds. Their surface behavior is often characterized as sociable, athletic, energetic, active, and nimble with rapid swimming. They can often be observed breaching, "roto-tailing" (a circular motion using the tail while jumping out of the water), jumping, and leaping up over 20 ft (7 m) above the surface of the water.

Bottlenose Dolphin (Tursiops truncatus)

 2008-09 Quota = 795

Bottlenose dolphins are commonly found in groups of 2 to 15 individuals. Offshore herds sometimes have several hundred individuals. This species is often associated with pilot whales and other cetacean species.
Bottlenose dolphins are generalists and feed on a variety of prey items "endemic" to their habitat, foraging individually and cooperatively. Like other dolphins, bottlenose dolphins use high frequency echolocation to locate and capture prey. Coastal animals prey on "benthic" invertebrates and fish, and offshore animals feed on pelagic squid and fish. Bottlenose dolphins employ multiple feeding strategies, including "fish whacking," where they strike a fish with their flukes and knock it out of the water.

Spotted Dolphin (Stenella attenuata)

2008-09 Quota = 400

Like other dolphins of the genus Stenella, these are relatively small dolphins, reaching lengths of 6 to 7 feet (2 m) and weighing approximately 250 pounds (114 kg) at adulthood. They have long, slender snouts or beaks. Like the Atlantic spotted dolphin (Stenella frontalis), pantropical spotted dolphins are without spots when born, accumulating them as they age until they are almost completely covered with overlapping patterns. Pan-tropical spotted dolphins are also distinguished by a dark "cape" or coloration on their backs stretching from their head to almost mid-way between the dorsal fin and the tail flukes and by a white-tipped beak.

Risso's Dolphin (Grampus griseus)

2008-09 Quota = 290

Risso's dolphins, sometimes called "gray dolphins," have a robust body with a narrow tailstock. These medium sized cetaceans can reach lengths of approximately 8.5-13 feet (2.6-4 m) and weigh 660-1,100 pounds (300-500 kg). Males and females are usually about the same size. They have a bulbous head with a vertical crease, and an indistinguishable beak. They have a tall, "falcate", sickle-shaped dorsal fin located mid-way down the back. Calves have a dark cape and saddle, with little or no scarring on their body. As Risso's dolphins age, their coloration lightens from black, dark gray or brown to pale gray or almost white. Their bodies are usually heavily scarred, with scratches from teeth raking between dolphins, as well as circular markings from their prey (e.g., squid), cookie-cutter sharks (Isistius brasiliensis), and lampreys. Mature adults swimming just under the water's surface appear white. 

Short-finned Pilot Whale (Globicephala macrorhynchus)

2008-09 Quota = 254

Short-finned pilot whales are larger members of the dolphin group reaching average lengths of 12 feet (3.7 m) for females and 18 feet (5.5 m) for males with maximum male size of 24 feet (7.3 m). Adult weight is 2200 to 6600 pounds (1000 to 3000 kg).
They have a bulbous melon head with no discernable beak. Their dorsal fin is located far forward on the body and has a relatively long base. Body color is black or dark brown with a large gray saddle behind the dorsal fin.
They are polygynous (males have more than one mate) and are often found in groups with a ratio of one mature male to about every eight mature females. Males generally leave their birth school, while females may remain in theirs for their entire lifetime.

False Killer Whale (Pseudorca crassidens)

2008-09 Quota = 70
These whales are gregarious and form strong social bonds. They are usually found in groups of ten to twenty that belong to much larger groups of up to 40 individuals in Hawai'i and 100 individuals elsewhere. They are known to "strand" in large groups as well. False killers are also found with other cetaceans, most notably bottlenose dolphins. To increase success of finding prey, these whales travel in a broad band that can be up to several miles wide.
Food sharing has been documented between individual false killer whales. They feed during the day and at night on fishes and cephalopods, and they are known to attack smaller dolphins that are involved in the tuna purse-seine fishery in the Pacific Ocean.


  1. This is great information. Thanks for sharing. =)

  2. Very informative post. Thanks!

  3. Thanks great information that all activists fighting to save the dolphin families, and communities that swim by Taiji should know.

  4. So... They mean common bottlenose right?