Disappearing Crayfish

It was not until crayfish became scare around the shores of the Hauraki Gulf that they obtained any real commercial value. Before World War Two crayfish were everywhere and could be easily harvested amongst the rocky reefs close to Auckland.

“Initially there were sacks coming off Waiheke and North Head. Fishermen didn’t need to travel to get crayfish … the problem wasn’t lack of crayfish. They were everywhere … After the war, crayfish were worth very little, something like thruppence a pound.”

Crayfish in pots
Crayfish being harvested in pots around the Red Mercury Islands. Note the generally small size of the animals, many which are under the limit and therefore have to be returned to the sea.

Then things changed. New equipment, such as echo sounders, enabled crayfishermen to  locate new reefs to target. Improved gear such as winches enabled fishermen to lift many more pots a day and larger boats enabled them to travel further afield. Once the export market opened up for live crayfish in Japan very high prices could be obtained, reaching over $80 a kilo. This incentivised continued crayfishing even when catch rates plummeted. Recreational divers also target crayfish increasing pressure on the stocks.

“Now catch rates are so poor, at only around a third of a kilo per pot, that crayfishermen are reliant on high prices to survive.”

Crayfishing out from Whitianga
Hauling a crayfish pot in fishing grounds out from Whitianga with a poor catch.

Scientific models suggest that, prior to human arrival, crayfish were the third most ecologically important benthic invertebrate group in the Hauraki Gulf. However, the impact of fishing activity since then has been so great that they are now considered to be ecologically extinct. Stocks are probably less than a quarter of their original levels.

There has been poor recruitment of crayfish into the Hauraki Gulf over the past 6 or so years, and this has exacerbated stock depletion, as a high level of fishing activity has continued during this period.

This has had flow on effects throughout the food web, as crayfish prey on sea urchins which in turn graze on kelp. When the number of crayfish in a system is reduced, the sea urchin numbers rapidly increase due to a lack of predation and they end up stripping the kelp off the rocks. This results in ‘kina barrens’ which are depauperate of reef life. This is why it is important that crayfish stocks are rebuilt to ensure healthy reef systems throughout the Hauraki Gulf.

Kina barren
A kina barren showing what happens when top predators such as crayfish and snapper are overfished, the kina explode in numbers and strip the rocks of kelp and other seaweeds.

Rangitoto baches are little gems

Some of the earliest baches in the Hauraki Gulf were constructed on the lava-strewn shores of Rangitoto Island. The island was purchased from Ngāti Paoa in 1854 primarily as a source of stone for the construction of Auckland. In 1890 the island was declared a recreational reserve. The Rangitoto Island Domain Board took over administration of the island and pursued a policy of opening up the island for pubic enjoyment. This involved the construction of a wharf on the southern side (Rangitoto Wharf) and the development of a track to the summit.

Rangitoto wharf waharoa
The first Rangitoto wharf was opened in 1897. Shown here is the new wharf which was opened in 2014 with the waharoa (customary gateway) welcoming visitors.

In 1911 the Domain Board started to lease out sites for campers in order to raise funds to cover the costs of administering the island. Eventually baches were built on the sites, with over 140 baches being built at 3 locations; adjacent to the Rangitoto Wharf, in Islington Bay and in McKenzie Bay near the Rangitoto Light. Vibrant holiday communities developed around the baches with families spending the entire summer school holidays there.

Isobel Conning (nee Simmons) remembers wonderful times at her family bach in Islington Bay before World War Two. “At night the bay would be full of yachts and launches. They were so numerous that you could almost walk across the bay on boats. Then someone, on one of the boats, would start up with a mouth organ. Someone else, in another boat, would follow. The crews would start singing and then people on the shore would join in.”

Simmons bach Rangitoto
Simmons bach in Islington Bay Rangitoto Island.

“One Islington Bay bach owner, Jock Loch, was noted for his unusual fishing methods. Wanting to fish from the comfort of his verandah he rigged up a line around a couple of pulleys, with one end attached to the outside of his house, and the other anchored in the sea. After baiting up his hooks, he would wind them down into the tide, tying a bell onto the rope, so that he would be alerted if there was a bite. He would then wind the line back up to his house, with the fish attached.”

By the 1920s there was disquiet about the impact of the baches on the island’s unique ecology. By 1937 a policy of gradually removing the baches had been adopted with owners being given 20 years to vacate and remove the structures. In 1957, when the 20 year time period had expired,  there was a reprieve when the remaining bach owners were granted a new lease for 33 years or the lifetime of the current owner. As the owners gradually reached the end of their lives, the baches started disappearing from the landscape.

Islington Bay bach and remaining infrastructure
At one time there were around 140 baches on Rangitoto Island. Now only some 34 baches remain. The empty infrastructure of vacant building sites and boat ramps can be seen around the coastline as shown here in Islington Bay.

Currently some 34 baches remain on Rangitoto Island. Rather than being seen as a blot on the landscape their historical and cultural value has now been recognised. But their future is still uncertain.

 

Recreational Fishing Park for the Gulf a good idea?

Read a Dialogue piece in today’s NZ Herald by Sue, Rod and Zoe Neureuter, the family who acts as guardians of the Noises Islands. Sue Neureuter’s personal Story of the Gulf features in The Story of the Hauraki Gulf.

“Creating a fishing park in a region in such alarming decline brings division where the opposite is required write Sue, Rod and Zoe Neureuter.”

Sue Neureuter on her boat at the Noises Islands
Sue Neureuter on her boat at the Noises Islands.

Prospective locations for the Auckland CBD

The location and naming of Auckland was determined by Irish sailor Captain William Hobson. Hobson had arrived in New Zealand as Lieutenant-Governor on 29 January 1840 aboard the HMS Herald. After the successful signing of the Treaty of Waitangi in the Bay of Islands on 6 February, Hobson set about determining the location for the new capital of the colony.

On visiting the Waitematā harbour on the invitation of Ngāti Whatua, Hobson was very taken with a prospective location in the upper harbour in the vicinity of what is now called Hobsonville. But he suffered a crippling stroke, and returned to the Bay of Islands, before confirming a location for the capital.

Vessels moored near Herald Island
Hobson was very enamoured with the upper Waitematā harbour as the location for New Zealand’s first capital, with its sheltered deep water. The area was subsequently named Hobsonville. Herald Island (shown on the left of this image) was named after the vessel on which Hobson visited the area, the HMS Herald.

Surveyor-General Felton Mathew was then instructed by Hobson to undertake another voyage to investigate prospective locations. Mathew was very enamoured with the Panmure Basin as the location for the new capital due to the low-lying and fertile volcanic soil, an abundance of freshwater draining from Maungarei (Mount Wellington), and proximity to the Manukau Harbour portage.

Panmure Basin Auckland
The Panmure Basin was another prospective location for the Auckland CBD due to its fertile, undulating land and ample freshwater.

When Hobson returned to the Waitematā on 6 July 1840 Hobson revisited the Hobsonville and Panmure locations but concluded that neither were suitable. The land at Hobsonville had poor fertility (evidenced by the stunted ferns growing in the area), little drainage and no obvious water supply. There was also very shallow water near the shore. The one significant downside for the Panmure option was the sand bar across the mouth of the Tāmaki River which made access by large vessels difficult.

The Watchman or Sentinal Island Herne Bay
It was whilst anchored near Watchman Island (the Sentinal) that Hobson’s doctor noted the promising look of the land on the southern shore near Herne Bay. This lead to further investigation and the ultimate establishment of Auckland on the Tāmaki isthmus on 18 September 1840.

Whilst the HMS Herald was anchored in the vicinity of Herne Bay near Watchman Island, Hobson’s physician Dr Johnson commented on the inviting appearance of the land on the southern shore. After closer investigation it was determined that the land looked promising and there was a deep anchorage close by. Hobson named the new settlement Auckland in honour of his benefactor Lord Auckland who had given Hobson command of a ship after six years of being stranded ashore.

Longline Fishing in the Gulf

Longlining was introduced into the Hauraki Gulf as a method of commercial fishing in 1912. It replaced the use of single baited hooks and immediately increased catches. Longling involves setting a main line, with numerous branches lines or snoods connected to it, each containing a baited hook. Each line can hold thousands of hooks. The method was quickly adopted and is still widely used in the Hauraki Gulf. It is a labour intensive, hands-on commercial fishing method, which is targeted and can produce very high quality fish.

Longline gear
Longlining involves the use of one main line (as shown on the drum here) to which hundreds of small branch lines with hooks are attached.
longline baiting the hooks
Hooks are pre-baited and stored on boards prior to being hooked onto the longline as it runs out from the boat.

In the early 1980s a lucrative market for fresh ‘iki jime’ snapper opened up in Japan. This involved spiking the fish in the brain after capture to kill it instantly, and then putting the fish into an ice slurry to rapidly cool its temperature. This resulted in a high quality fish which fetched premium prices. Longline fishermen in the Gulf rapidly adopted the new methods, initially pioneered by Leigh Fisheries.

Longline bringing in the line
Longlining involves retrieving each fish individually. This means that a higher quality of fish can be harvested in comparison to bulk methods such as trawling and Danish seining.
Longline spiking the fish
Longline snapper are spiked in the brain immediately after capture to retain quality. Shown here is a fishermen about to use a spike on a snapper.
longline snapper in slurry
Once released from the line, the snapper are placed into an ice slurry which quickly reduces their temperature also helping to retain quality.

The fish are transported back to port on the same day, sent to the factory for packing and then quickly flown out to high value markets around the world including Australia, the USA and Europe.

Longline vessel unloading a catch at Leigh
Leigh Harbour is still a popular port for longline fishing boats. Shown here is a vessel unloading its catch into a truck for transport to the Leigh Fisheries factory in Leigh.

“Thanks to Dave Moore from Wildfish and the skipper and crew of Coral V for taking me out on a great long lining trip. I was very impressed by how hard you guys worked.”

Hauraki Gulf’s special whales

A group of Bryde’s whales have chosen the Hauraki Gulf as a place to live all year round and as somewhere to bring up their calves. This is unusual for a whale species, as most migrate from the tropics to the polar regions each year. We are very lucky to have a population of whales right on Auckland’s doorstep and we need to look after them.

View this fantastic drone video of the Bryde’s whales in the Gulf taken by AUT scientists.

Bryde’s whales are small baleen whales that can often be seen feeding amongst seabirds and dolphins in large ‘boil ups’ of fish in the Hauraki Gulf. The population is considered to be threatened, being listed by the Department of Conservation as “nationally critical”.

The whales used to be hunted, with 19 animals being taken at the whaling station at Whangaparapara, Great Barrier Island during the 1960s. However, Bryde’s whales do not produce much oil so they were not targeted in the same way that humpback whales were.

Old Whangaparapara Whaling Station
19 Bryde’s whales were taken at the Whangaparapara whaling station on Great Barrier Island during the 1960s. The remains of the old whaling station, shown here, can still be seen in the harbour.

The biggest risk the whales now face is being hit by the large ships that transit the Gulf to enter the Port of Auckland. The shipping lanes cut right across the areas where the whales spend much of their time, and if they are hit by the large hulls travelling at high speed, the whales have little chance of surviving. A total of 18 whales are known to have died from ship strike in the Hauraki Gulf since 1996.

Container ship leaving the Port of Auckland
Large ships are a risk to whales if they travel at fast speeds transiting through the Hauraki Gulf. If the ships slow down to 10 knots or less that risk is significantly reduced.

Responding to this issue, in 2013, Ports of Auckland issued a voluntary protocol that advised ships to reduce speed, where possible, when transiting through the Gulf. At speeds of 10 knots or less there is a much higher chance that the whales will survive a collision. Since the release of the protocol, speeds have been reducing and are now on average less than 11 knots. There has only been one recorded whale death from ship strike, on 12 September 2014, since the protocol was put in place.

Bryde's whale Transit Protocol page 1 Bryde's whale Transit Protocol page 2

Origin of the name Coromandel

Coromandel harbour was named after the visit of the HMS Coromandel to the harbour in June 1820. The entire peninsula now also bears the vessel’s name. The name itself originates from India, where the Coromandel was originally built, and refers to the Indian south-eastern coast.

Coromandel harbour showing oyster farms
Coromandel Harbour looking towards Whanganui Island and showing an oyster farm and moored boats.

Hauraki Gulf Seabird Hotspot

The Hauraki Gulf has an extraordinary wealth of seabirds, supported by its productive marine area, diverse habitats and numerous predator free islands. Over 80 species have been seen in the region which comprises 20 per cent of the world’s total species. Of these at least 27 species breed in the wider Hauraki Gulf region.

Group of fleshfooted shearwaters off teh Mokohinaus
Group of flesh footer shearwaters off the Mokohinau Islands in the Hauraki Gulf

Seabirds spend most of their lives at sea; they only come to land to breed. Although many of the birds travel enormous distances, some to the north and eastern Pacific – to waters off Japan, Hawaii, California and Ecuador – others venturing down to the Polar Front, they return each year to breed in burrows on the Gulf’s islands.

Maria Island the Noises
Maria Island in the Noises Group is one of the many islands within the Hauraki Gulf where seabirds breed.

Historically, seabirds would have also bred on New Zealand’s mainland, but the destruction of habitats and predation by introduced animals have left the remnant populations mostly on islands. Where once seabirds brought fertility to soils, adding nutrients through the decomposition of guano and dead eggs, chicks and adults, farmers now spread fertiliser, much of it derived from seabird islands elsewhere in the Pacific.

Birders at the Mokohinau Islands
Overseas birders out at the Mokohinau Islands to view the Hauraki Gulf’s very special seabird populations.

The Hauraki Gulf’s rich seabird population attracts birders from all over the world. Threats to the seabirds include longline fishing hooks (the birds dive on the bait and get caught on the hooks), predators at breeding sites and lack of food through overfishing and depletion of fish stocks, especially bait fish.

Setting a tori line on a long line fishing boat
A longline fishing boat with a tori line set out the back at dawn to avoid seabird capture on the hooks as they are set.

Commercial fishers are adopting seabird friendly fishing methods to avoid seabird bycatch which include setting their lines at night, weighting the lines so they sink quickly and running tori lines over the top of the long line.

 

Hauraki Gulf Māori place names

Many of the Māori names for the islands and waterways of the Hauraki Gulf are wonderfully descriptive of the natural environment. Here are a few.

Waitematā Harbour: Water as smooth as obsidian

Waitemata harbour from Point Chevalier
Waitematā Harbour from Point Chevalier looking towards the North Shore.

Pakatoa Island: Ebb and flow of the tide

Pakatoa Island showing old holiday resort
Pakatoa Island showing old holiday resort.

Rātōroa [Rotoroa] Island: Prolonged sunset

Rotoroa Island from the air
Rotoroa Island from the air showing the restoration work.

Pō-nui Island: Great extended night

Ponui Island homestead Oranga bay
Homstead at Oranga bay on Ponui Island

Rangitoto: Blood reddened sky

Sunset looking out to Rangitoto Island from Omana Beach
Rangitoto viewed from Ōmana Beach, Maraetai at sunset.

Tiritiri-o-Matangi: Sanctified heaven of fragrant breezes

Hobbs Beach Tiritiri Matangi
People enjoying Hobbs Beach Tiritiri Matangi Island

‘Goat Island’ Marine Reserve World First

The marine reserve surrounding Goat Island near Leigh, called the Cape Rodney-Ōkakari Point Marine Reserve, was the first no-take marine reserve in the Hauraki Gulf, in New Zealand and probably in the world. It was established in 1975 after a long campaign by scientists at the Leigh marine laboratory.

The idea was first mooted in 1965 by Professor Valentine Chapman who suggested that the scientists needed a place where their scientific equipment was protected and where the fish weren’t eaten.

Leigh marine reserve from teh north
Goat Island was chosen as the site for the first marine in reserve in the Hauraki Gulf in 1975.

Chapman wrote to the then Marine Department suggesting that a marine reserve should be established. But they showed no interest in taking action on the basis that there was no legislation on the statute books enabling government to establish a reserve in the sea.

Leigh glass bottom boat
The marine reserve at Leigh attracts thousands of visitors each year and supports local business such as the glass bottom boat.

But Chapman wasn’t put off. He simply escalated the issue. He wrote to the Marine Department every month and obtained support from Ngāti Manuhiri, the Marine Sciences Association and the New Zealand Underwater Association. He also held public meetings and addressed school groups. In the end the government passed the Marine Reserves Act 1971 and created the new reserve in 1975.

The marine reserve has been an outstanding success. The abundance of fish has increased substantially and hundreds of thousands of visitors visit each year. It is a place where parents can take their children to see underwater life. It is also a great tourist attraction for visitors to New Zealand.

Bill Ballantine
The late Bill Ballantine was a fearless promoter of marine protection and he was the first Director of the Leigh Marine Laboratory.

The reserve has served as inspiration for other marine reserves around the Gulf, throughout the country and overseas. The late Bill Ballantine was a strong advocate for the reserve and he was the driving force behind the Leigh Marine Laboratory for many years.