Reproduction of a hector's dolphins

Feeding

The use of echolocation is very dominant for them to find their foods sources. Primarily, they will dine on various fish and squid. They will follow the fish where they move for spawning, and that is when you will see the Hector’s Dolphin closer to the shorelines. Even though they can dive for up to 3 minutes, they usually only do so for about 1 ½ minutes at a time. During that span of time, they are able to get a substantial amount of food.

Reproduction

Females take part in mating when they are from 7 to 9 years of age. For males it ranges from 5 to 9 years. When a pair is going to mate, they spend time with courtship rituals. They can include chasing, leaping, displaying the belly, and touching. They will also move through the water in very close proximity to each other.

It takes from 10 to 12 months after mating for the calf to arrive, tail first. The young arrive either in the later part of spring or the early summer. The young form very close bonds with their mother and they will be fully weaned about 2 years of age. The development stage of a Hector’s Dolphin will often play a role in where it goes in the pod. Sometimes they will be with juveniles, other times with breeding populations, and then at times with non-breeding populations.

One of the concerns for this species of dolphin is their slow rate of reproduction. The females will have a calf once every 2 to 4 years. They won’t mate until the young calf they are caring for is completely weaned and taking care of its own needs. The average lifespan in the wild is from 20 to 25 years.

Conservation Status and Threats

The overall population of Hector’s Dolphins is estimated to be about 7,400 at this time. They are classified as a species that is vulnerable at this time. They were once widely hunted to be used as fishing bait but that is no longer allowed. Chemicals and other types of pollution do continue to be common threats for them.

Stress created by boats is common for these dolphins. They tend to swim closer together when boats are around. It is possible doing so helps them to reduce some of that stress. Limiting boating in certain areas where they live can be helpful. Efforts to reduce pollution have also been helpful.

In 1988 The Department of Conservation created the Banks Peninsula Marine MammalSanctuary to help them. The goal of this effort has been to help reduce the risk of Hector’s Dolphins getting tangled up in commercial fishing nets.

(source:google/http://www.dolphins-world.com/)