Kārearea Protecting a southern land November 2020 How long is a piece of string? Stoats, penguins & genomics Jane Young ou can't make a piece of string any longer – or three kilometres. Forensic markers in stoat DNA can be shorter – by measuring it. But you can make a used to help determine where the invaders are likely to Ybetter job of protecting biodiversity if you can have come from, and provide useful information about measure the numbers, distribution and behaviour of the most efficient way to deploy traps or poison baits. the microbes, animals and plants that make up New In July this year it was announced that the 2.4 billion Zealand's unique ecosystems. DNA bases of the stoat genome had been sequenced. These measurements can involve some very Over 20,000 protein-coding genes had been identified. sophisticated – and expensive – technology. Recently, I This detailed information may make it possible to watched a webinar on the sequencing and mapping of develop new toxins that are more specific for stoat the stoat genome. It was all fascinating stuff, although proteins, which will reduce the risk of bycatch. some of the technical info made my head hurt. But even More controversial, are suggestions that gene without being able to understand the finer points of drives could be used to control or even eliminate stoat SNPs, SINEs or STRs (genomics has more acronyms than populations altogether. Gene drives are designed to your average government department), it's possible to spread a harmful gene through a whole population glimpse the enormous potential that this knowledge of pests or predators. In the case of stoats, where the has for conservation work. development of embryos is naturally delayed after In the case of stoats, for example, DNA from saliva fertilisation, it might be possible to manipulate the or scat (faeces) can give information not just about genes responsible in order to reduce fertility. whether there are animals present in an area, but about You might think that mustelids (stoats, ferrets and their gender and relatedness. Tieke (saddlebacks) are weasels) would be too small to trouble a yellow-eyed an indicator species for the presence of stoats. If tieke penguin, but the chicks can be extremely vulnerable. can be spotted, you can be pretty sure that there are no In the 2019-20 breeding season, despite a predator stoats around. Conversely, a single stoat incursion can trapping regime being in place, three of the 49 chicks at spell disaster for a tieke population. Moeraki were killed. Staff at Penguin Rescue made the In 2015, a flourishing tieke population at difficult decision to take the remaining chicks into care Orokonui ecosanctuary, north of Dunedin, until the danger was removed. It seemed most likely was wiped out by a stoat incursion. Cont p2 Two of the stoats were caught Yellow-eyed penguin chick fairly quickly, and DNA tests carried out by Ecogene identified them as siblings. To the dismay of the Orokonui staff, however, there was footprint and camera evidence that at least one more stoat was present. After a prolonged campaign, the stoat and her two Stoat kits were finally located and dispatched with the aid of a trained conservation dog called Macca. No predator proof fence, such as the one at Orokonui, is completely fail-safe. But most areas of New Zealand aren't protected at all and are completely open to stoat invasion. Stoats can run, climb, and even swim for up to How long is a piece of string? cont from p1 that stoats were responsible, but a change to the trapping strategy actually resulted in the capture of three ferrets. Hopefully in the future the ready availability of genomic information and testing will provide speedy, definitive answers about the identity of predators. Penguins in the Catlins are known to have been killed by dogs. Forensic profiling could be used to confirm which individual animal is responsible. New applications for genomic technology have been coming in thick and fast. Yellow-eyed penguin studies, for example, have benefited from DNA analysis of penguin faeces that makes it possible not only to determine what prey the birds are eating, but also what Low-tech predator monitoring uses inked tracking proportion of each species is found in their diet. Faeces tunnels at the Yellow-eyed Penguin Trust's Long Point can be collected when the penguin are away from the Reserve in the Catlins. The tunnels are made from nest, so no stress is caused to the birds, unlike the use of upcycled election ads with the political messages the only technique available a few decades ago, which carefully obscured with green paint. Since 2010, involved forcible evacuating their stomach contents. South Otago Forest & Bird volunteers have carried Researchers are concerned that blue cod now out predator trapping at this and other Catlins sites. makes up more than half of the penguin's diet at the Although there is little or no evidence that penguins expense of key species that were available to them a are now being killed by introduced predators at few decades ago. Penguin numbers have plummeted Long Point, nest numbers have decreased by about during the last seven years for a variety of reasons. In 90% since 2013. Forest & Bird members have been the Catlins, starvation is the most significant factor. We lobbying for more than three decades to get marine don't have time to wait until all the results are in, but all protection for the Catlins. the evidence we have indicates that a priority must be protection of their foraging grounds. Marine Metre Squared (Mm2) Project An opportunity to help monitor the NZ environment South Otago KCC carry out an Mm2 study at Kaka Point in the Catlins 2 Nov 2020 Kārearea I Spy Sharks! Let’s be honest. When it comes to sharks, many of us have never got past Jaws. (Peter Benchley later regretted writing the blockbuster thriller on which the paranoia-inducing movie was based.) The reality is that sharks are beautiful, superbly adapted animals that, worldwide, are in big trouble because of human impacts. Researcher Rob Lewis tells us about Shark Spy, the citizen science project set up to help provide data that will underpin the conservation of NZ sharks. harks are crucial parts of marine food webs where they act as middle and top predators. SThey control the populations of their prey, not only by consuming them, but also by controlling their feeding behaviour. Remove the sharks, and the whole ecosystem becomes unbalanced. Sharks are also simply impressive animals, whose ancestors go back as far as 450 million years. To ensure the health of New Zealand’s coastal ecosystems in the future, we need to monitor shark populations and maintain their wellbeing if necessary. New Zealand sharks seem to be generally faring ok, but we are missing some key pieces of information on shark species that would help us better understand and conserve their populations. These include population parameters such as diversity, seasonality, coastal movements, residency, and population structure (age, sex, size). Sharks reproduce much more slowly than bony fish, so their populations don't recover as quickly from impacts such as overfishing or habitat degradation. Shark Spy is a citizen science project with the dual aim of (1) collecting baseline data on sharks local to New Zealand coasts to fill the gaps in our knowledge, and (2) connecting schools and the local community to their coastal environment via contribution and collaboration in the project. Shark Spy has partnered with school and community groups in order to actively collect information on sharks using baited underwater video systems (BUVs). These school and community groups not only collect the Seven gill shark data, but aid in its analysis as well. In tandem with the BUV surveys, Shark Spy also collects information about sightings from the community. Anyone who has seen a Rough skate shark or an egg case and snapped a video or picture can help us grow our database. If you have a sighting of a shark or an egg case and want to help, you can submit this info to us in one of PATERSON INLET, STEWART ISLAND these three ways: • Go to www.inaturalist.org and search for Shark Spy. Then simply upload your encounter. As long Carpet shark as it is a shark it will automatically be added to our database. • Upload your encounter to our Facebook page – simply search for Shark Spy Otago. • Email your encounter to: [email protected]. TAIAROA HEAD, OTAGO If you would like to get further information, to ask questions, or request a talk for a club or group by one of Spiny dogfish our scientists, you can reach Shark Spy on: [email protected]. 3 Nov 2020 Kārearea Red-billed gulls – where are they nesting? Sally Carson New Zealand Marine Studies Centre ed-billed gulls/Tarapunga (Larus novaehollandiae scopulinus), are common residents of the New RZealand coast, or so it seems. They frequent our beaches, try to steal our lunch and squawk loudly when we come too close. Most New Zealanders have seen red-billed gulls and many can identify them by name. Although they are commonly encountered, recently they have been designated as a threatened species due to a steady decline in numbers at their largest breeding colonies. Laura Findlay Understanding where red-billed gulls are breeding in Otago is part of a new participatory science project, The red-billed gull's nest is a simple bowl of seaweed, run by the Royal Albatross Centre. Although most large twigs and grass, about 30 cm wide.