10 facts you didn't know about common dolphins
1. There are several recognised species of common dolphin around the world. The ones in New Zealand are known as the short-beaked common dolphin (Delphinus delphis).
2. They are called common dolphins as they have been sighted in every ocean and most seas (except polar regions). However, it does not mean they are common everywhere, in fact in some areas of the world they are considered to be endangered!
3. The first abundance estimate in the Hauraki Gulf was completed in 2016 and it was found that an estimated 10,500 common dolphins had been using Auckland's waters over the four-year study - that's a lot of dolphins!!
First Mate Sarah-lyn used to be a Research Assistant on the common dolphin abundance estimate project!
4. Normally an oceanic species found in deeper waters, the common dolphin species is resident to the Hauraki Gulf year round thanks to plenty of food and sheltered waters for raising young calves.
5. Common dolphins are often seen hunting and feeding in large groups. There are usually a variety of seabird species and sometimes whales feeding in the same place as these dolphins!
6. They are one of the only dolphins which are tricolour - grey, white and yellow in a distinctive hourglass pattern.
A porpoising common dolphin clearly shows it's unique yellow hourglass pattern
7. They are also quite a small species of dolphin, growing to around 2.5m and a weight of 200kg.
8. Dolphins produce lots of different sounds to communicate with each other and locate food. If you listen closely, you can sometimes hear them whistling to each other when they are bow-riding at the front of the Dolphin Explorer!
9. The common dolphin can be seen in groups of different sizes from small groups of 20-30 animals to groups joining together to form super- or megapods which can result in thousands of animals!
10. The Hauraki Gulf Marine Park is a calving ground. Most common dolphin babies are born in the summer when the water is warmer meaning they have a higher chance of survival.
Two calves flanked on the outsides by their presumed mothers