New Zealand Coastal Seabirds
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A fisher’s guide: New Zealand coastal seabirds In this companion guide From Australasian gannets to a number of threats, including to A Fisher’s Guide to yellow-eyed penguins, this guide being caught in New Zealand gives distinguishing physical fisheries. While some of New Zealand Seabirds characteristics, ecology, range New Zealand’s fisheries have you can learn about and potential threats to each effective mitigation measures in additional seabirds species listed. It also provides place to reduce the number of the current New Zealand seabirds being killed and injured, that you may see in conservation status of each a number of others need to New Zealand’s EEZ. species. We’ve included the better address this issue if future While some of these Ministry for Primary Industries generations are to enjoy these seabirds migrate great Species Code and Group remarkable birds. Code for each species to assist It’s our goal with this guide to distances and may be fishers in accurately recording provide you with the information species interactions. seen far from shore, many you need to identify and are likely to be seen near Protection of seabirds is learn more about some of the our coasts or even inland. provided for under the Wildlife seabirds you might see around Act 1953. Most of the birds New Zealand’s coasts. in this guide breed only in New Zealand and many face List of seabirds found in this guide Gannets Otago shag Mid-sized petrels Australasian gannet Leucocarbo chalconotus and shearwaters Morus serrator Foveaux shag Fluttering shearwater Leucocarbo stewarti Gulls Puffinus gavia Black shag Black-backed gull (kelp gull) Hutton’s shearwater Phalacrocorax carbo novaehollandiae Larus dominicanus dominicanus Puffinus huttoni Little black shag Black-billed gull North Island little shearwater Phalacrocorax sulcirostris Larus bulleri Puffinus assimilis haurakiensis Little shag Red-billed gull (silver gull) Cook’s petrel Phalacrocorax melanoleucos brevirostris Larus novaehollandiae scopulinus Pterodroma cookii Pied shag Pycroft’s petrel Terns Phalacrocorax varius varius Pterodroma pycrofti Black-fronted tern Pitt Island shag Chlidonias albostriatus Stictocarbo featherstoni Storm-petrels Black-bellied storm-petrel Caspian tern Spotted shag Fregetta tropica Hydroprogne caspia Stictocarbo punctatus punctatus White-fronted tern Grey-backed storm-petrel Sterna striata striata Penguins Garrodia nereis Fiordland crested penguin New Zealand storm-petrel Shags Eudyptes pachyrhynchus Fregetta maoriana Chatham Island shag Little blue penguin Leucocarbo onslowi New Zealand white-faced storm-petrel Eudyptula minor Pelagodroma marina maoriana New Zealand king shag Yellow-eyed penguin Leucocarbo carunculatus Megadyptes antipodes NZ Conservation Status: Not Threatened MPI Species Code: XGT MPI Group Code: XSU Species group: Australasian gannet Gannets Morus serrator Feeding and range Eats: Fish and squid. Range: When not breeding, gannets disperse widely over the continental shelf, including harbours, estuaries, bays, and fiords. Juvenile gannets migrate to Australia and are common off eastern and southern Photo: © M. P. Pierre Photo: © M. P. Photo: DOC Australia ranging as far west as the Indian Ocean. Distinguishing characteristics • large seabird (84–91 cm in length) • white body with dusty yellow colouring on top of head Interesting facts Gannets plunge dive from great heights • white wings with dark flight feathers in pursuit of their prey. When diving they • wingspan approximately 1.7 to 2 metres can reach speeds up to 145 km an hour • long, bill that is pale grey and dive to depths of more than • short, thick black legs 15 metres. Juvenile features Gannets are specially adapted for plunge diving, for example they have air • mottled grey-brown plumage that lightens each year until they sacs in their lower neck to help cushion reach maturity the impact when they hit the water. Breeding Threats Breeding sites: Numerous small islands, At sea as well as the mainland in New Zealand. A few gannets are caught in the trawl fisheries and by line-fishing Colonies are found at the Three Kings techniques such as trolling for kahawai. Islands, Poor Knights, Mokohinau Islands, islands off Great Barrier Island, the Gannets have been found dead on beaches after swallowing fish hooks Coromandel Peninsula, White Island, or becoming entangled in fishing line. west coast of the North Island, Tolaga Gannets tend to take non-commercial fish such as pilchards or small size Bay, Cape Kidnappers and Black Rocks. classes of commercial fish stocks. Periodic die-offs of pilchards and other South Island breeding sites are at fish appear to increase gannet mortality rates. The largest recorded wreck Farewell Spit, Marlborough Sounds of gannets on New Zealand beaches occurred in 1995 when 283 gannets and Little Solander Island. died of starvation due to a pilchard die-off event. The species also breeds in Australia. On land Breeding period: Gannets return to The main threat to mainland gannet colonies is disturbance by dogs their breeding colonies around June or and humans. July each year. Both parents take turns Gannets at mainland colonies can, however, become tolerant of people protecting first the egg and then the chick. as long as they keep their distance from the colony itself. Frequency of breeding: Annual. The colony on White Island has to survive periodic volcanic eruptions, Number of eggs: One egg, but can and some eggs and chicks are lost in thermal areas. replace it if the egg is lost. Nesting: Gannets usually breed in large colonies. NZ Conservation Status: Not Threatened MPI Species Code: XBG MPI Group Code: XSG Species group: Black-backed gull (kelp gull) Gulls Larus dominicanus dominicanus Feeding and range Eats: Scavenges on carcasses of whales, seals, fish and birds, also feeds on eggs, chicks and adult birds, and catches small fish. Frequently scavenges at refuse tips. Range: Gulls disperse over coastal and continental seas, land, lakes, Photo: © M. P. Pierre Photo: © M. P. Photo: © M. P. Pierre Photo: © M. P. and rivers. The same species is common on coasts of temperate Distinguishing characteristics and subantarctic landmasses • very large gull (49–62 cm in length) – largest gull in New Zealand around the southern hemisphere. • white head and body • upperwings are black with some white on the tips • underwings are white Interesting fact • bright yellow bill with a red dot on the lower bill They open shellfish by picking them up • pale greenish-yellow legs and feet and flying straight up before dropping Juvenile features them on the sand, rocks or asphalt so • although a similar size, juveniles look like a completely different bird, with that the shell will break. mottled brown plumage and black bills and feet • juveniles do not develop full adult plumage until they are about three years old Breeding Threats Breeding sites: Breeds in loose At sea colonies or individually throughout Black-backed gulls, which often scavenge prey items, are prone to ingesting New Zealand, including on numerous plastic or getting entangled in plastics. offshore islands. Recorded as bycatch in commercial fisheries. The species also breeds in eastern and southern Australia, the Antarctic On land Peninsula, South America and Mustelids (especially stoats and ferrets) and feral cats take eggs and chicks at South Africa, and many subantarctic mainland colonies. Norway rats may also take eggs and chicks at some colonies. islands. Other possible introduced predators include hedgehogs. Breeding period: Return to breeding Uncontrolled dogs are a major threat to chicks. sites in October. Incubation is completed in 25–30 days and chicks Human disturbance is a primary cause of nest failure. Motorbikes and 4WD fledge at about 50 days. vehicles on beaches or riverbeds disturb nesting birds and sometimes destroy nest sites. Frequency of breeding: Annual. Number of eggs: Two to three eggs, and can lay up to three clutches if eggs are damaged or lost. Nesting: Nest on the mainland at beaches, estuaries, sandspits, shellbanks, lake margins, rocky headlands, riverbeds, farmland, roofs of buildings, and even on mountain-tops. NZ Conservation Status: Nationally Critical MPI Group Code: XSG Species group: Black-billed gull Gulls Larus bulleri Feeding and range Eats: Insects, small fish and will also scavenge. Range: Breed only in New Zealand. Black-billed gulls disperse widely in the winter after breeding with some recorded inland over farmland, lakes, and rivers but most flock at Photo: © M. P. Pierre Photo: © M. P. Walmsley Photo: DOC. Photographer Andrew coastal estuaries and over inshore seas. Birds regularly visit Stewart Distinguishing characteristics Island and have straggled to the • small gull (35-38 cm in length) Snares Islands. • white head and body • long, thin black bill • wings are grey on top with narrow black tips and white underneath Interesting fact • dark legs and feet In New Zealand the black-billed gull • similar size and colouring to red-billed gulls, but the black-billed gull is paler, is considered in serious decline and is with less black on the wing tips vulnerable to predation. For example, • adults are easily distinguished by bill colour over a two-month period in 2006, one cat and a ferret killed hundreds of black- Juvenile features billed gull chicks on the Aparima River • similar features, but darker wings, and pale bill and legs in Southland. Breeding Threats Breeding sites: Breeds on both the At sea North Island and South Island. Few known threats at sea. Key South Island strongholds are in Southland (Mataura, Oreti, Aparima On land and Waiau rivers) and Canterbury The most serious threat to gull populations is from mammalian predators (Ashburton, Opihi, and Waiau rivers). such as Norway rats, ship rats, cats, stoats, ferrets, hedgehogs, possums, pigs, and dogs. All these predators take eggs, and most are capable of Although overall, the population is in killing adults and chicks. decline, black-billed gulls have been expanding their range northwards in Farmed or feral stock can impact gulls by trampling nests or increasing erosion.