Water & Atmosphere June 2015 Weathering the storm How science serves the stormiest region on earth Building resilience Dealing with the growing pains of urbanisation Cleaning up Island solutions to pollution Actions stations on climate Putting better climate data to good use Water & Atmosphere June 2015 Cover: Severe Tropical Cyclone Pam at peak strength near Vanuatu on 13 March 2015. (NASA) Water & Atmosphere is published by the National Institute of Water & Atmospheric Research (NIWA). It is available online at www.niwa.co.nz/pubs/wa Enquiries to: 4 News The Editor SENSITIVE SOULS: where whitebait Water & Atmosphere really spawn NIWA GLIDE TIME: a new underwater Private Bag 14901 Kilbirnie exploration tool Wellington 6241 NEW MARINE LIFE: 141 new creatures New Zealand found in three years email: [email protected] ©National Institute of Water & Atmospheric Research Ltd 2015 6 In brief ISSN 1172-1014 Counting fish in Tonga, tracking South Water & Atmosphere team: Island pollution, beer science, the life of freshwater bugs, a new spectrometer Editor: Mark Blackham in Antarctic, and tracing land use in Production: NIWA Communications and Marketing Team sediment Editorial Advisory Board: Geoff Baird, Mark Blackham, Bryce Cooper, Elizabeth Griffin, Barb Hayden, Rob Murdoch 8 Panorama Science helping out in the Pacific John Morgan, NIWA CEO Follow us on: 20 NIWA in the Pacific Working with our Pacific partners facebook.com/nzniwa 32 Gallery twitter.com/niwa_nz Pacific Portrait – Photographer Dave Allen visits Kiribati with a NIWA team google.com/+niwanz 37 Profile Nava Fedaeff is a spirited addition www.niwa.co.nz to NIWA’s climate capability 39 Solutions Water & Atmosphere is produced using vegetable-based inks on Quantifying the fiscal benefits of paper made from FSC certifed mixed-source fibres under the ISO environmental research 14001 environmental management system. enhancing the benefits of New Zealand’s natural resources 2 Water & Atmosphere June 2015 www.niwa.co.nz 10 Building resilience How the Pacific is grappling with building urban environments in a region prone to natural hazards 17 Cleaning up Novel and pragmatic solutions are being found to pollution caused by development and population growth 26 Climate action stations A new generation of climate forecasting is helping Pacific Islanders adjust to weather changes 29 Samoa's climate choices Forecasts from Samoa’s climate early warning system are used throughout the nation www.niwa.co.nz Water & Atmosphere June 2015 3 Sensitive souls Research on the spawning biology of whitebait species shows that populations of the native fish are highly sensitive to a wide range of human-related factors, not just fishing. While whitebaiters lament declining catches, concerns are also being raised about overfishing. NIWA freshwater ecologist Dr Paul Franklin says recreational fishing is just one human factor influencing populations of whitebait in New Zealand waterways. He says the species’ unusual spawning habit of laying eggs in temporarily submerged plants is a high-risk reproductive technique easily affected by human use of land and water. Whitebait are the juveniles of five species of native fish that return to freshwater after spending the first few months of their lives at sea. This migration into freshwater is a critical part of their life cycle, as they move upstream to find the habitats where they will feed, grow into adults, mature Scooped from a net at Neil's Beach, Jackson's Bay. (Colin Monteath, hedgehoghouse.com) and then begin the cycle all over again. After spawning sites of the giant kōkopu “Mortality at sea is something we can’t “As we use waterways in different (Galaxias argenteus) were discovered for control – the only way we can (increase ways there is a greater impact on the first time in a suburban Hamilton populations) is by improving the number the life cycle of the fish. Activities stream in 2013, Dr Franklin set out to (of larval fish) that gets there in the first from agriculture to power generation understand more about the spawning place.” constantly change flow and flooding biology of the five whitebait species. conditions. Dr Franklin said changing land and “All five species deposit their eggs in water use was influencing spawning. “Riparian management is also a habitats – vegetation and grasses – only factor. Given that spawning takes “The unusual reproductive strategy temporarily submerged by high water place in bankside vegetation, anything of whitebait makes them uniquely levels. For inanga (Galaxias maculatus), that affects this (mowing, clearing or susceptible to changes to river flows which migrate downstream to estuaries planting) can have an effect. The type and bankside vegetation. The eggs to lay their eggs, this is high spring of vegetation is also important. For of inanga, for example, are typically tides. For the other four species, this is example, fish won’t spawn at all in the laid within dense grasses that retain high river flows caused by rainfall. lower Waikato River where glyceria (an moisture and provide shading. These introduced plant) is common.” “It’s not clear why they would do this, conditions help the eggs survive out because it is a high-risk strategy.” of water until they are ready to hatch Dr Franklin said it was clear that many about three to four weeks later. elements determined overall whitebait An average-sized adult female inanga populations. will lay about 2000–3000 eggs. On “The eggs then hatch when the average, only about 11 per cent survive spawning sites are re-inundated by “What this emphasises is the to hatch, and once the eggs hatch and future high river flows or, in the case susceptibility of the species to changes the larvae make it to sea, survival is very of inanga, high spring tides. The larvae in habitat, and in all stages of their low. There is no specific information are then washed out to sea, where they life cycle there are things that impact on inanga, but mortality of larval fish stay for several months, before finally them. in the marine environment has been returning to freshwater as whitebait.’’ “Only by considering all these things estimated at 98 per cent. That meant that if the eggs were not re- together will we get a clearer picture.” submerged within a suitable time, they would die. 4 Water & Atmosphere June 2015 www.niwa.co.nz Gliding time A state-of-the-art underwater research glider has been unveiled by NIWA scientists in Wellington. Coastal oceanographer Joanne O’Callaghan has taken delivery of the 1.5-metre long glider, which can carry a variety of sensors to measure temperature, salinity, light, oxygen and fluorescence under the surface of the ocean. NIWA discovers The Slocum Glider – named Manaia, after the representation often carved into the figureheads of sea-going waka to give 141 new creatures spiritual direction to the waka's journey – is one of about 500 NIWA biologists have discovered 141 new marine creatures around the world, but is the first in New Zealand. The gliders in the past three years, an important contribution to the are named after Joshua Slocum, the first man to sail alone worldwide register of underwater life. around the world. The glider is designed to travel the oceans alone, like Captain Slocum, and will be initially deployed off The World Register of Marine Species (WoRMS), published northeast New Zealand. in Ostend, Belgium, has almost completed logging all the world’s known marine species. The list relies on Unlike powered submarines, the glider does not use a contributions from marine biologists around the world. propeller to move through the water. It moves by changing its buoyancy to glide up or down in the ocean. Wings on the More than 1000 new-to-science marine fish species have glider convert vertical displacement into horizontal motion, been described globally since 2008 – an average of more resulting in a vertical saw-tooth dive pattern down to 200m, than 10 per month – according to the scientists completing at a horizontal speed of about one kilometre per hour. This the consolidated inventory of all known ocean life. efficient means of locomotion leaves most of the on-board Among new fish species worldwide are 122 new sharks battery power for operating the scientific instruments it and rays, 131 new members of the goby family, and a new carries. A glider deployment usually lasts about 30 days, barracuda found in the Mediterranean. during which time the glider will travel about 400km through the ocean. A recent NIWA-led inventory of New Zealand’s marine species counted close to 12,500 named marine species O’Callaghan says the data, transmitted via a phone call for the WoRMS. At least 3000 more species are in New made during occasional surfacing, will be valuable for Zealand museum collections awaiting formal naming and understanding the coastal shelf seas around New Zealand. description. Satellites have collected measurements about the ocean’s NIWA’s Dr Dennis Gordon, who led New Zealand’s marine surface for more than 30 years, but, just as the weather is species inventory, and two other NIWA biologists, are part of constantly changing above us, so is the ocean below us. an editorial group that determines which species should be We have very limited information on sub-surface variations in the WoRMS. Dr Gordon also helped shape the higher-level in temperature, salinity, oxygen and biological parameters management classification of life used by the WoRMS. The in water shallower than a few hundred metres – what we latest version of this classification is about to be published. consider to be the Continental Shelf. Dr Gordon says New Zealand is still in the discovery Manaia will help gather more data on the part of the ocean phase when it comes to marine life.