Facts about sharks/mangō

Introduction

Find out more about the different species of shark/mangō found in New Zealand waters.

Many species of sharks and rays live in shallow coastal waters at least for part of the year. The most familiar of these are the school shark, rig, spiny dogfish, shorttail stingray and eagle ray. Many of the larger species are wide-ranging, open-ocean species such as the mako, whale shark, pelagic stingray, spinetailed devil ray and manta ray.

The greatest diversity of New Zealand’s sharks and rays occurs on the upper continental slope between 200 m and 1800 m depth. This zone is characterised by many species of often bizarre looking dogfishes and skates.

Encounters with large sharks, those reaching more than 1.5 m total length, in coastal waters usually happen over spring and summer when many species move inshore to give birth and feed. These include the broadnose sevengill shark, common thresher shark, mako, great white shark, bronze whaler, blue shark and smooth hammerhead.

While mako and blue sharks are normally found well offshore in oceanic waters they are sometimes seen close to shore during summer. Blue sharks will occasionally enter large harbours and the surf zone at this time.

Shark facts

  • Sharks and rays belong to the class of fish called Chondrichthyes – fish with skeletons of cartilage, not bone.
  • About 110 species of chondrichthyans are found in New Zealand waters, of which 73 are sharks, 25 are rays and 12 are chimaeras (a.k.a. ghost sharks); like other types of marine life these numbers will change as scientists continue to discover or recognise new species of sharks and rays from our waters.
  • New Zealand sharks are diverse – they range in size from the tiny pygmy shark which grows up to 27 cm long, to giant basking and whale sharks which can exceed 10 m in length.
  • The basking shark and whale shark are the largest fishes in the world and feed almost exclusively on copepods and krill (small shrimp-like animals) and small bait fishes.
  • It has been estimated that a 4.5 m great white shark can survive for a month and a half and swim over 3500 km on 30 kg meal of whale blubber.
  • The cookie cutter shark feeds on large fish and marine mammals by taking a single circular, cookie-shaped bite from their flesh or blubber.
  • Sharks continuously replace their teeth throughout their lives; some sharks generate new teeth every eight days. 
  • In the 180 years before 2020, there have only been 15 fatal shark attacks documented in New Zealand.

Protected sharks and rays

The following species are protected under the Wildlife Act 1953:

It is an offence to hunt, kill, disturb, or possess or trade in any part of these species. Anyone accidentally catching a protected shark or ray must release it immediately and report the circumstances to DOC. Commercial fishers must also report captures of protected species to Fisheries New Zealand, Ministry of Primary Industries (MPI).    

Great white sharks, basking sharks and oceanic whitetip sharks are also protected under the Fisheries Act 1996, this means that in addition to being protected within New Zealand waters these species are protected from New Zealand vessels fishing on the High Seas.

Threats

Many species of sharks and rays are vulnerable to overfishing because of their low biological productivity (i.e. slow growth, late age at maturity and small number of young).

Research and management of sharks and rays is guided by the National Plan of Action for the Conservation and Management of Sharks (NPOA Sharks). The effects of fishing on New Zealand sharks and rays are managed by Fisheries New Zealand, MPI, under the Fisheries Act 1996. .  Catches of the main commercially fished species, rig (spotted smoothhound), school shark, spiny dogfish, blue shark, porbeagle, mako shark, elephantfish, rough skate and smooth skate, are regulated through the quota management system (QMS).

 In some places coastal nursery areas of sharks are threatened by coastal development and run-off, particularly fine sediment, from the land.  Sharks are also vulnerable to ingestion of, and entanglement in marine debris.  Little is known of how shark populations will respond to the effects of global climate change but profound changes to many of the ecosystems that support them are expected.

Significance to Māori

Kapeta/school shark and mangō / rig were important seasonal foods of Māori and were taken with nets and lines in large well organised fisheries. The flesh once dried kept for a long time and was an important form of koha at hui and tangihanga. Whai/skates and rays were taken with nets, lines, and harpoons.

Shark liver oil was also mixed with red ochre to make paint. Items of jewellery (necklaces, pendants and earrings) were made from the teeth of larger species particularly mako and occasionally great white sharks / mangō taniwha. In some cases, pendants resembling shark teeth were fashioned out of bone.

Sharks appear in many Māori creation stories and legends, and many important or tapu / sacred places had kaitiaki/guardians that took the form of sharks or rays. One story of the origin of sharks is that they are the progeny of Te Pu-whakahara and Takaaho (one of the children of Rangi and Papa), who appointed them, along with whales and dolphins, inhabitants of freshwaters. However, they refused and persisted in roaming the oceans.

DOC's work with sharks

DOC includes all sharks and rays recorded from New Zealand waters in threatened species assessments of marine fishes. This work includes research on the correct identification of New Zealand species and the description of newly recognised species.

DOC also contributes information and expertise to global threat assessments of sharks and rays by the IUCN Shark Specialist Group.

DOC works with scientists from crown research institutes, universities, government agencies and NGOs in New Zealand and internationally to improve our knowledge of the biology, movements and management of protected and threatened species of sharks and rays.

Several shark species (including their parts and derivatives) are protected under the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES). CITES protection aims to ensure that international trade in not putting the species long term survival in the wild at risk. To import/export these species, CITES permits are required to be obtained and presented as the items cross international borders.

Related link

Sharks - Ministry of Primary Industries website