The Pathway ahead for hoiho Te ara whakamua Impacts on hoiho: Literature review and recommendations Report written by Dr Trudi Webster Conservation Science Advisor | Kaitohutohu Pūtaiao-whāomoomo Yellow-eyed Penguin Trust | Te Tautiaki Hoiho February 2018 This work was funded by grants to the Yellow-eyed Penguin Trust from Otago Regional Council and Otago Museum IMPACTS ON HOIHO: LITERATURE REVIEW AND RECOMMENDATIONS CONTENTS | HE RĀRAKI UPOKO EXECUTIVE SUMMARY | HE WHAKARĀPOPOTOTAKA .......................................................................... 4 TERRESTRIAL IMPACTS | KĀ PĀKA UTA ............................................................................................... 4 MARINE IMPACTS | KĀ PĀKA KI TAI ...................................................................................................... 5 RECOMMENDATIONS | KĀ WHAKATAUKA ........................................................................................... 6 Gaps in knowledge ................................................................................................................................. 6 Research implications .......................................................................................................................... 7 Conservation management implications .......................................................................................... 8 USE OF THE MARINE ENVIRONMENT | KĀ MAHIKA KI TAI .................................................................. 10 USE OF THE TERRESTRIAL ENVIRONMENT | KĀ MAHIKA KI UTA ..................................................... 11 MARINE IMPACTS | KĀ PĀKA KI TAI ........................................................................................................ 13 FISHERIES .................................................................................................................................................. 13 Bycatch ................................................................................................................................................... 13 Ecosystem effects ................................................................................................................................. 15 Habitat disturbance ............................................................................................................................ 18 Aquaculture .......................................................................................................................................... 19 Management of fisheries .................................................................................................................... 20 FISHERIES RECOMMENDATIONS ...................................................................................................... 23 CLIMATE AND WEATHER RELATED IMPACTS ................................................................................... 25 Direct effects of weather and climate .............................................................................................. 26 Indirect effects of weather and climate ........................................................................................... 27 Management of climate ...................................................................................................................... 30 CLIMATE RECOMMENDATIONS ......................................................................................................... 30 POLLUTION ............................................................................................................................................... 31 Oil pollution .......................................................................................................................................... 31 Marine debris ....................................................................................................................................... 32 Sedimentation ...................................................................................................................................... 33 Increased nutrients and eutrophication ......................................................................................... 33 Heavy metals ........................................................................................................................................ 34 Persistent organic pollutants ............................................................................................................ 35 Marine biotoxins .................................................................................................................................. 35 Invasive species ................................................................................................................................... 37 Sound ...................................................................................................................................................... 37 Page 1 Management of pollution ................................................................................................................... 37 POLLUTION RECOMMENDATIONS .................................................................................................... 38 MARINE PREDATION ............................................................................................................................... 39 Pinnipeds ............................................................................................................................................... 39 Sharks and cetaceans .......................................................................................................................... 40 Barracouta ............................................................................................................................................ 40 Management of marine predation .................................................................................................... 41 MARINE PREDATION RECOMMENDATIONS ................................................................................... 41 TERRESTRIAL IMPACTS | KĀ PĀKA UTA ................................................................................................. 42 TERRESTRIAL PREDATION .................................................................................................................... 42 Mustelids ............................................................................................................................................... 43 Cats ......................................................................................................................................................... 43 Dogs ........................................................................................................................................................ 43 Pigs ......................................................................................................................................................... 43 Rats and mice........................................................................................................................................ 43 Other species ........................................................................................................................................ 44 Management of terrestrial predation .............................................................................................. 44 TERRESTRIAL PREDATION RECOMMENDATIONS ......................................................................... 45 HABITAT DEGRADATION ....................................................................................................................... 45 Land use changes ................................................................................................................................. 45 Fire .......................................................................................................................................................... 46 Harvest ................................................................................................................................................... 47 Management of habitat degradation ............................................................................................... 47 HABITAT DEGRADATION RECOMMENDATIONS ............................................................................ 47 HUMAN DISTURBANCE ........................................................................................................................... 48 Tourism ................................................................................................................................................. 48 Research ................................................................................................................................................ 49 Recreation ............................................................................................................................................. 50 Management of human disturbance ................................................................................................ 50 HUMAN DISTURBANCE RECOMMENDATIONS ................................................................................ 51 DISEASES AND PARASITES ..................................................................................................................... 51 Viral infections ....................................................................................................................................