Chatham Islands

Geographical Information:  43º 40’S – 44º 25’S to 177º 00’W - 176º 00’W, in the South Pacific Ocean, 860 kilometres east of New Zealand
Area:  They have a total area of 97,000 hectares which is spread unevenly amongst some 40 different islands. Chatham Island (90,000 hectares) and Pitt Island (6,190 hectares) are the only two islands permanently inhabited by people.
Maximum Altitude:  283  metres

About 65 million years ago, marine volcanism began to form the group. Over the millenia, erosion and sea level changes have produced a varied landscape of volcanic outcrops, sand dunes, lagoons and peat bogs, each with its own set of natural environments.

The geology of the archipelago is complex, consisting of ancient volcanics and schists and more recent sediments, including limestone. The land has been uplifted, eroded and drowned several times. This has resulted in a mosaic of habitats: steep, gentle, wet, dry, acidic, lime-rich, exposed and sheltered. The richness and distinctiveness of the flora and fauna reflect that.

The Chatham Islands are located at the eastern extension of the Chatham Rise which runs due west towards New Zealand and which together with Campbell Plateau, the Lord Howe Rise, Norfolk Rise and Three Kings Rise, is considered to be part of the ancient supercontinent Gondwanaland.

The islands are the only part of the Chatham Rise above sea level. This results in part from block faulting initiated about 100 million years ago and exposing older rocks of which the basement rock, Chatham Schist is the oldest and in part results from repeated episodes of basaltic volcanism in the last 80 million years. Different formations of limestone and other associated sedimentary rocks indicate episodes and prolonged histories of marine submergence and emergence. This has largely been due to sealevel changes associated with the ice ages and from the late Pliocene era (2 million years ago) through the Pleistocene to the present.

The convergence zone of the colder (north bound) ocean currents from the south and the warmer (southbound) ocean currents from the north surround the Chatham Islands. Climatically, the islands reflect their mid latitude oceanic setting. Temperate conditions predominate, low 20 degrees Celsius in mid summer and 5 – 8 degrees in mid winter, with mists associated with ocean current convergence, and strong prevailing north-west and south-west winds.

The first human habitation of the Chatham Islands involved migrating Polynesian tribes who settled the Islands, and in their isolation became the Moriori people. The exact origin of these people remains a matter of some dispute. The Moriori population of the islands numbered about 2,000. Their agricultural resources were not suited for the colder Chathams, so they lived as hunter-gatherers, taking food from the sea and from native flora. Whilst their new environment deprived them of the resources with which to build ocean-going craft for long voyages, their intelligence and perseverance saw the invention of the most ingenuous craft afloat. Moriori built what was known as the waka korari, a semi-submerged craft constructed of flax and lined with air bladders made from kelp. This craft was used to travel to the outer islands on ‘birding’ missions. The Moriori society was a peaceful one and bloodshed was outlawed by the chief Nunuku after generations of warfare. Arguments were solved by consensus or by individual duels of singular combat rather than warfare – but at the first sign of bloodshed, the fight was over.

The name ‘Chatham Islands’ comes from the ship HMS Chatham of the Vancouver Expedition, whose Captain William R. Broughton landed on 29 November 1791, claimed possession for Great Britain and named the islands after the political head of the Royal Navy. A relative of his, Thomas Pitt, was also a member of the Vancouver Expedition. Sealers and whalers soon started hunting in the surrounding ocean, using the islands as their base. It is estimated that 10 to 20 per cent of the indigenous population soon died from diseases introduced by foreigners. The sealing and whaling industries ceased activities about 1861, while fishing remained as a major economic activity.

On 19 November 1835, a British ship carrying 500 Maori armed with guns, clubs and axes arrived, followed by another ship on 5 December 1835 with a further 400 Maori. They proceeded to massacre the Moriori and enslave the survivors. A Moriori survivor recalled: "The Maori commenced to kill us like sheep... we were terrified, fled to the bush, concealed ourselves in holes underground, and in any place to escape our enemies. It was of no avail; we were discovered and killed – men, women and children indiscriminately". A Maori conqueror justified their actions as follows: “We took possession...in accordance with our customs and we caught all the people. Not one escaped....”

After the invasion, Moriori were forbidden to marry Moriori, nor to have children with each other. All became slaves of the Ngati Tama and Ngati Mutunga invaders. Many died from despair and many Moriori women had children to their Maori masters. A small number of Moriori women eventually married either Maori or European men. Some were taken from the Chatham Islands and never returned.

An all-male group of German Lutheran missionaries arrived in 1843. When a group of women were sent out to join them three years later, several marriages ensued and many members of the present-day population can trace their ancestry back to the missionary families.

The Moriori numbers fell to 101. Most of the Maori eventually left the Chathams by 1870. It was Solomon’s grandfather, the chief of the Rauru tribe, who convinced the Moriori to remain pacifist during the invasion of their land. Tame Horomona Rehe Solomon, known as Tommy Solomon, the last full blooded Moriori, died in 1933.

The Chatham Islands were the last islands in the Pacific to be settled by people. Residents today are descended from Moriori, Maori and Europeans, and their distinctive culture is reflected in the many significant archaeological and historical sites. There are various wahi tapu and burial sites, as well as remnants of European settlement relating to whaling and farming. Evidence of Moriori occupation includes the internationally significant Moriori tree carvings (rakau momori) at J. M. Barker (Hapupu) National Historic Reserve.

Flora:  Most of the land is fern or pasture-covered, although there are some areas of forest. Of interest are the macrocarpa trees, with branches trailing almost horizontally in the lee of the wind. The islands are generally hilly, Pitt more so than Chatham, although the highest point, at 299 metres (981 feet), is located on a plateau near the southernmost point of the main island of Rekohu. This island is dotted with numerous lakes and lagoons, notably the large Te Whanga Lagoon. Other lakes on Chatham include Huro and Rangitahi. Rekohu has a number of streams including Te Awainanga and Tuku.

The Chatham Islands form a complex archipelago well to the east of the New Zealand mainland. They have been isolated for more than 80 million years – long enough to develop many plants found nowhere else. These include forest trees, several giant herbs and seaweeds. Even the local flax (Phormium ‘Chathams’) is different. Of 388 indigenous terrestrial plant species, 47 (about one eighth) are endemic to the Chatham Islands. Most well-known of the endemics is the Chatham Island Forget-me-not Myosotidium hortensia, Rautini Brachyglottis huntii, Chatham Islands Kakaha Astelia chathamica and Soft Speargrass Aciphylla dieffenbachii.

The plants of the Chathams show a much higher proportion of coloured flowers than in mainland New Zealand. Examples are the Chatham Island Forget-me-not (blue), Linen Flax Linum monogynum var. chathamicum (blue), Chatham Island Geranium Geranium traversii (pink), Swamp Aster Olearia semidentata (mauve), keketerehe O. chathamica (purple), and Giant Sowthistle Embergeria grandifolia (purple).

The leaves of the Chathams’ species are also often fleshier and trees bigger than their New Zealand counterparts. The Chathams’ plants do not generally show juvenile forms.

Plants have colonised the Chatham Islands in the past from both the northern and southern parts of the New Zealand region. Species with northern affinities include Chatham Islands Nikau (possibly related to Rhopalostylis baueri subspecies with affinity to the palms of Norfolk Island and the Kermadec Islands), Kowhai (Sophora chathamica, also found in western North Island) and the three Hebe species: H. barkeri, H. dieffenbachi, and H. chathamica. Those with a southern or Subantarctic connection include Swamp Heath (Dracophyllum scoparium, found also on Campbell Island), Keketerehe, closely related to a shrub daisy of Fiordland and Stewart Island) and Rautini (closely related to Brachyglottis stewartiae of The Snares, Solander Islands and small islands in Foveaux Strait).

The oceanic setting of the Chatham Islands has had a profound influence on the plant life. Winds sweep the islands, bringing gales, salt spray, cloudy skies, frequent showers and occasional blasts of cold air. But temperature extremes, droughts, frosts and snow are rare. Annual sunshine hours are about half those of the sunny parts of the New Zealand mainland.

Plants have adapted to these conditions in many ways. Some, such as Tarahinau (Dracophyllum arboreum), have wind-resistant needle leaves. Protective leaf and twig furriness is a feature of the tree and shrub daisies, and the indigenous trees have the remarkable ability to layer themselves after having been blown over.

Other species have developed giant leaves. Examples of these include megaherbs such as the Chatham Islands Forget-me-not and Giant Sowthistle Embergeria grandifolia. Gigantism is also evident among trees and shrubs. Chatham Islands Karamu Coprosma chathamica, which grows into a forest tree, is by far the largest species in a genus of shrubs. Tree Koromiko Hebe barkeri is also the largest of its genus, and Akeake Olearia traversii is one of the largest tree daisies on earth. Button Daisy Leptinella featherstonii is a woody shrub – all other members of its genus are creeping herbs. These significant enlargements may be due to the climate, long isolation and high soil fertility.

Megaherbs, the Button Daisy and fleshy herbs such as Cook’s scurvy grass Lepidium oleraceum evolved and thrived in soils made highly fertile through the effects of millions of sea birds inhabiting the islands. The decline in the abundance of these plants is partly due to the loss of seabirds. The cool humid overcast climate has also influenced the plants of the Chathams in other ways. Tree ferns predominate in the forests, where they provide germination sites on their trunks for seedlings of forest trees, as well as filmy ferns and orchids. Peat has developed as a result of thousands of years of accumulated plant matter, mostly from sphagnum moss and the rain of Tarahinau needles.

People have lived in the Chatham Islands for many hundreds of years and many plants have been introduced. The most significant introduced tree is Karaka or Kopi Corynocarpus laevigatus, brought centuries ago from mainland New Zealand by Moriori. It was cultivated in groves, eventually becoming widespread and self-perpetuating in the forests. The kernel/seed of Kopi is highly toxic if eaten raw, but was an important source of carbohydrate when prepared appropriately.

Other mainland New Zealand plants brought more recently and now well established include Cabbage Tree, Tree Fuchsia, Tutu, Karamu and flaxes. More sinister are weeds from other countries. Gorse, Broom, Selaginella, Old Man’s Beard, Sweet Briar, Cotoneaster, Elderberry and Himalayan Honeysuckle are all a worry. Worse though is Chilean Guava, also known locally as Cranberry, which seems superbly adapted to flourish in Chatham Island peatlands, progressively elbowing out the indigenous vegetation unless controlled.

Chatham Island Wetlands

Wetlands on the Chatham Islands are extensive and diverse, containing around 8.5% of New Zealand’s threatened freshwater fish.

Although the annual rainfall is relatively low at 500–1500 millimetres (20 to 59 inches.) for Waitangi, the land is of low relief, rising to just 299 metres (981 feet.), and with gently rolling slopes, so that drainage is poor. Peat development is encouraged by the climate, as it is cloudy, cool, coastal, humid, and windy. About 60% of the land surface is covered with peat (to about 10 metres (33 feet.) deep in places) or peaty soils. Bogs occur on elevated peat surfaces where they are nourished only by rainfall, and are therefore quite infertile. Small valleys carry moving groundwater and a certain amount of nutrients from mineral soils, and these are occupied by fens and swamps.

Lakes, ponds, and pools of many sizes are common, some associated with peatland and others enclosed by sand dunes. These provide further wetland habitats, especially shallow freshwater aquatic habitats with marshes around their margins. Close to the coast, the strong influence of sea salt produces distinctive wetland communities: seepages with coastal wetland plants, damp turf vegetation on headlands and on shallow peats overlying rock, and small estuaries with tidal marshes.

The wetland interface between land and sea is especially well represented around the margin of Te Whanga, a huge shallow coastal lagoon that occupies a fifth of the area of Chatham Island. Te Whanga is valued as a source of freshwater fish such as Inanga and Patiki, as well as swan eggs and cockles. Its marginal zones of mudflats, shell ridges, saltmarsh turf and rushlands are important for many coastal, freshwater, and migrant wading birds.

Habitat degradation has contributed to the extinction of some bird species associated with freshwater habitats including Brown Teal, Chatham Island Fernbird, and Chatham Island Rail. Game birds such as Black Swan and ducks are present on several bodies of water.

Many Chatham Islands wetlands have been affected by fire, livestock – especially cattle, sheep and pigs – and wild animals, but compared with mainland New Zealand they are less impacted by nutrient enrichment and weeds. The freshwater aquatic habitats of lakes and rivers, for example, have so far escaped invasion by the many potentially troublesome aquatic weeds.

Fauna:
The Chatham Islands are home to a number of endemic birds. The most famous species on the islands are the Magenta Petrel and the Black Robin, both of which came perilously close to extinction before being saved through conservation efforts. Other endemic species are the Chatham Island Oystercatcher, the Chatham Gerygone (Grey Warbler) the Parea or Chatham Islands Pigeon, Forbes’ Parakeet, the Chatham Islands Snipe and the Shore Plover. Several species are extinct, including the three endemic species of rail, Chatham Islands Raven and the Chatham Islands Fernbird.

Of the 24 species of seabird which breed on the Chatham Islands, six of them are New Zealand’s most threatened seabirds, while several species have already become extinct in the islands following human settlement. The Chatham Island Taiko is now regarded as the world’s rarest seabird and is classed as a critically endangered endemic with a total population of 100 to 140 birds and only 6 known nesting burrows.

In the past, the Chatham Islands swarmed with animal life. Marine birds and mammals came ashore to breed or roost, bringing nutrients to enrich the soil. The forests were alive with bird and invertebrate life. Waterways supported huge numbers of wetland birds and fish. The shore was a treasure trove of shellfish, crustaceans, fish and birds. Harvesting, large-scale clearance of vegetation (especially forest) for farming, and human-imported animals have taken a large toll on the wildlife.

Rats, mice, pigs, possums, hedgehogs, cats and dogs consumed innumerable indigenous animals and their food supplies. Cattle, sheep, goats, pigs, horses and possums have reduced the complex indigenous vegetation cover to scattered fragments. These animals are now controlled in most areas of the Chathams, which are protected.

Several bird species have become extinct since humans arrived at the Chatham Islands. They include a penguin, a swan, several ducks, several flightless rails, a fernbird and a bellbird. Endemic seabirds that have survived include Toroa (Northern Royal Albatross), which also breeds at Taiaroa Head near Dunedin; Chatham Island Taiko (now confined to one tiny population); Torea (Chatham Island Oystercatcher) found around the shores; Chatham Island Shag and Pitt Island Shag, and Chatham Petrel. The Chatham Petrel was confined to Rangatira Island until 2002 to 2005, when the New Zealand Department of Conservation began to establish a second population on Pitt Island. More recently, in April 2008, 43 chicks were moved from Rangatira Island to artificial burrows within the Sweetwater Conservation Covenant in the south of the main Chatham Island. This was the first return of an endangered bird species to the main Chatham Island, made possible by landowners Liz and Bruce Tuanui, and the Taiko Trust, who predator-proof fenced the two and a half-hectare Sweetwater Covenant with the aim of restoring seabirds to the site. This includes the critically endangered Chatham Island Taiko which was successfully transferred there for the first time in 2007.

Surviving endemic land birds include Parea (Chatham Island Pigeon), Chatham Island Sarbler, Forbes’ Parakeet, Chatham Island Snipe, Chatham Island Tui, Chatham Island Tomtit and Black Robin. None of these birds are common and recovery programmes are underway for the most threatened of them.

Many seabird species are still quite common around the Chatham Islands. Buller’s Mollymawk, prions, skuas, Sooty Shearwaters, storm-petrels and Little (Blue) Penguins are most likely to be seen at sea. Around the coasts, those most frequently seen include the Black-backed Gull, Red-billed Gull, White-fronted Tern, shags and skuas. Banded Dotterel and Pipit are often found on shore as well.

 Te Whanga Lagoon and the freshwater lakes and swamps of Chatham Island provide extensive habitat for wetland birds. Most common are Black Swan, Black Shag, Mallard and Grey Ducks, Pukeko, Welcome Swallow, Pied Stilt and various migratory waders. In open country, meaning farmland, bracken and shrubland, introduced finches and songbirds are common, as are Harrier, Spur-winged Plover and Buff Weka.

 Weka, imported from Canterbury (where they are now extinct) around 1905, have proliferated to such an extent that they are regarded as something of a pest at times, and are also a favourite seasonal menu item. Birds of the forests include the Kakariki (Red-crowned Parakeet), Parea, Chatham Island Warbler and Chatham Island Fantail. Chatham Island Tui and Chatham Island Tomtit are now confined to Pitt Island, although a few Tuis visit the main Chatham Island.

Taiko
The Chatham Island Taiko, Pterodroma magentae, endemic to the Chatham Islands, has a population estimated to number less than 150 birds. It was in fact believed to be extinct for almost a century, until its rediscovery by David Crockett in 1978. Nearly 10 years later, in 1987, the first Taiko burrow was discovered in southern Chatham Island. The arrival of mammalian predators, particularly cats, pigs, and rodents, the introduction of Weka and the loss of forest habitat are likely to have been the main causes of decline within the last 100 years. Stray dogs and trampling of burrows by domestic and feral stock are likely to have been additional threats. The key present-day threat to Taiko continues to be predation from cats, pigs, Weka and rodents during the Taiko breeding season.

 Taiko is one of the larger Gadfly Petrels weighing between 500 and 600 kilograms (17½ and 21 pounds.) and has a wingspan of around one metre (3.3 feet.). The plumage is black with a white breast. The Taiko is an ocean wanderer, spending its entire life at sea and feeding in the subtropical waters of the South Pacific Ocean between the Chatham Islands and South America. It returns to land only to breed. Current population estimates range between 120 and 150 individuals, with only 14 known breeding pairs. The New Zealand Government’s Department of Conservation classes the Taiko as category A – the highest priority for conservation management. The IUCN Red List Categories (IUCN 1994) also ranks Taiko as critically endangered.

The breeding grounds are located in dense forest in the south-west of the main island. Sub-fossil and historical evidence suggests that they once bred in huge numbers in the southwest of the island. Once Europeans arrived along with introduced mammalian predators, however, the Taiko all but disappeared within 100 years.

Magenta Petrel or Taiko
Taiko, like all Gadfly Petrels, are very vocal both in the air and on the ground, and have a large repertoire of calls. Common to many species is a ‘ti-ti’ call; other calls include long, low frequency moans and persistent churring sounds.

More than other tubenoses, Gadfly Petrels will often respond to human imitations of their calls. This has become a very useful technique for encouraging some of the more endangered species such as the Bermuda Petrel and the Galápagos Petrel to sites where they can be better protected. This technique is also planned for use with the Taiko.

Breeding takes place during the Southern Hemisphere summer, from September until May. Adults return in late September to clean out and prepare their burrows. Taiko are a burrowing petrel that can construct burrows up to 5 metres (16½ feet.) in length which the male excavates. The end of the burrow opens into a nest chamber where the chick will spend the first 105 days of its life after hatching. The breeding pair will use the same burrow each year and usually mate for life with the same partner. A single white egg is laid around the end of November or beginning of December. Both parents share incubation over a period of 55 days. Once the chick hatches, usually around the middle of January, both parents will feed it for approximately 105 days until the chick is ready to fledge. When the chick is finally ready, it will climb a tree in the dense forest and then launch itself for the five kilometre flight to the coast and out into the South Pacific Ocean. The Taiko chicks will then remain at sea for seven or eight years until they are ready to return to the Chatham Islands, find a mate and breed.

Chatham Island Black Robin
The recovery of the Chatham Islands Black Robin from the brink of extinction is an internationally renowned conservation success story. This little black bird is only found on the Chatham Islands. Numbers continue to increase, but because it still has such a small population it is classified as critically endangered. The Black Robin can live to be 13 years old and it grows to 15 centimetres high. It eats insects such as cockroaches and Weta, as well as grubs and worms.

Black Robins often pair for life. Females usually lay two eggs and often re-lay if a clutch is lost. All the Black Robins alive are descended from that last breeding pair, named ‘Old Blue,’ and ‘Old Yellow.’

Black Robins live in woody vegetation beneath the canopy of trees. They spend a lot of time in the lower branches of the forest in order to shelter from the strong winds that buffet the Chatham Islands group. They also like foraging in the deep layers of litter found on flat areas of the forest floor.

They are currently located on South East Island and Mangere Island in the Chatham Islands group. Attempts are being made to establish another population in a fenced covenant on Pitt Island.

In 1972, wildlife officers could find only 18 Black Robins living on Little Mangere Island. In 1976 there were a mere seven birds left. These were all moved to Mangere Island where 120,000 trees had been planted to provide better shelter. By 1980 a further two birds had died and none had bred.

The outlook was bleak, but a dedicated team of New Zealand Wildlife Service staff took the daring step of cross-fostering eggs and young to another species to boost productivity. The last breeding pair, named Old Blue and Old Yellow, and a foster species, the Chatham Island Tits, ended up saving the Black Robin from extinction. The fostering programme used to save the Black Robin was such a fantastic success that it has been used as a case model on how to save endangered birds around the world. With the Black Robin population now well established on Mangere and South East Islands, the Department of Conservation is attempting to establish a third population in a predator-free area of Pitt Island. There are even hopes that the Black Robin may one day be returned to its ancestral home, Little Mangere, where the vegetation is slowly regenerating. Today the population stands at around 250.

Native Grey Warbler (Riroriro)
The Native Grey Warbler or Riroriro, Gerygone igata, and the endemic Chatham Island Warbler, Gerygone albofrontata, are New Zealand’s only members of the Australasian family Pardalotidae. They sing a delicate and complex trill, which Maori took as a seasonal reminder to plant their crops. The Grey Warbler weighs 6.5 grams (0.23 pounds); the Chatham Island species weighs 9 grams (0.32 pounds). Grey warblers have adapted well to human changes to the landscape, but Chatham Island Warblers prefer undisturbed sites.

The females of both species build enclosed pear-shaped nests with side entrance holes, usually hanging from a branch. They lay four white eggs with reddish speckles, each nearly one-quarter of the mother’s body weight, in seven days. The males defend the territory while the females incubate the eggs alone. Then males help feed the chicks while females prepare to lay a second clutch.

A Shining Cuckoo may lay an egg in the Warbler’s second clutch. The Cuckoo chick typically hatches first and expels the warbler’s eggs or chicks. It is fed by the apparently unsuspecting warbler until it fledges. Both species mainly eat invertebrates and some small fruits. They glean food from leaves, and sometimes the Grey Warbler hovers beside branches to catch prey.

Shore Plover
Rangatira Island in the Chathams was, until recently, the last home of the endangered Shore Plover, Thinornis novaeseelandiae, down to only 130 birds in the wild by the 1990s. In 1991, 14 of these small wading birds were hatched from eggs taken from the Chatham Islands and transferred to the National Wildlife Centre (NWC). Incredibly, only a year later, the birds paired and bred at one year old, thus beginning the captive breeding programme. In 1994, the first releases of captive-bred plover into the wild were trialled, with transfers to Motuora Island in the Hauraki Gulf. A total of 75 birds were produced in captivity and released there over the following 5 years.

Unfortunately the programme was not successful in establishing a new Shore Plover population, with released birds dispersing from the predator-free island to neighbouring estuaries and beaches where they were probably killed by predators. This is a highly mobile species, and it was thought that the birds were being scared off the island by resident Morepork. Another predator-free island was sought – one that also lacked avian predators. A suitable privately owned island off the east coast was found in 1998. Now all the young Shore Plover raised at NWC are released here and the island has a very healthy population, thought to be self-sustaining. While some of the birds have dispersed, enough have stayed to make the project a success. With one wild Shore Plover population established, attention now turns to another suitable safe island haven upon which to release the next five years’ worth of progeny.

The Shore Plover is a small member of the plover/dotterel family (Charadriidae). The head is black in males, brown in females. Both have a white band across the forehead. The bill is orange with a dark tip. They can be noisy, making loud, ringing calls, especially in aggression towards neighbours. The alarm call is a loud, repetitive ringing ‘ching’, which is sustained until the threat has passed. They are strongly territorial during the breeding season, but in winter they may roost and feed in flocks. The Shore Plover nests from mid-October to January, with both the male and female incubating. Nests are hidden under thick vegetation, or in holes or crevices amongst boulders and driftwood. They lay two to three dark blotchy eggs, which are incubated for 28 days. The chicks fledge at approximately 35 days of age.

The New Zealand Shore Plover was once widespread around the New Zealand coastline and the Chatham Islands, but by the 1880s, Shore Plover were restricted to the Chatham Islands only. Introduced predatory mammals such as cats and rats are thought to have caused their extinction on the New Zealand mainland.

After the introduction of cats to the Chathams, shore plover remained only on predator-free Rangatira Island, otherwise known as South East Island, and Western Reef in the Chathams group. The population there is approximately 120 birds – which makes the Shore Plover one of the rarest shore birds in the world.

Shore plover live on coastal rocky wave platforms, sandy and rocky beaches, saltmeadows and river mouths. They feed on small crustaceans (copepods, ostracods, amphipods, isopods), spiders, molluscs (gastropods, bivalves), insects and their larvae.

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