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New Zealand penguins - current knowledge and research priorities

Authors:
  • Global Penguin Society

Abstract and Figures

The New Zealand region is a hot spot for seabirds and hosts six of the world’s eighteen penguin species; of these, four are endemic species that occur only in New Zealand. Despite this regional species richness and New Zealand’s reputation for international leadership in species conservation, very little is actually known about our penguins. In comparison to most other non-NZ penguin species, there is a dearth of information about the biology and ecology of most New Zealand penguin species. Five of our six penguin species are in decline. There is very little published literature for most New Zealand penguins, which means that the reasons for those population declines remain unknown. Consequently, current conservation actions principally revolve around occasional population counts and ad hoc research or conservation actions that may or may not address the real threats. With ever increasing pressure from anthropogenic factors, be it climate change, pollution, or fisheries interactions our penguins are in trouble. In order to prevent or reverse their population declines and to put in place evidence based management, we first need to identify the actual rather than the perceived threats. For this research is essential. In this report, we collate the information available on all six New Zealand penguin species. This includes published accounts (scientific papers, reports), grey literature (unpublished reports and data sets), and personal observations made by of researchers that have worked with New Zealand penguins.
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... Interactions with recreational and commercial fisheries pose a risk to the species across the entire mainland range, as each incident of bycatch-related mortality removes a potential breeding individual from the population. Survival to adulthood is only c. 20.5%; however, survival increases to c. 87% in adult birds [33,42]. Survival rates of chicks and juveniles are much lower than adult survival; c. 20.5% as juveniles compared to c. 87 as adults [33,42]. ...
... Survival to adulthood is only c. 20.5%; however, survival increases to c. 87% in adult birds [33,42]. Survival rates of chicks and juveniles are much lower than adult survival; c. 20.5% as juveniles compared to c. 87 as adults [33,42]. Nutritional stress resulting from poor quality or insufficient prey returned by adults has been identified as a contributing factor to low survival rates in chicks [35,43], whereas a combination of low fledging mass and risk of bycatch while dispersing from natal sites contributes to low juvenile survival [31,35]. ...
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Technical Report
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Article
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Camera loggers are increasingly used to examine behavioural aspects of free-ranging animals. However, often video loggers are deployed with a focus on specific behavioural traits utilizing small cameras with a limited field of view, poor light performance and video quality. Yet rapid developments in consumer electronics provide new devices with much improved visual data allowing a wider scope for studies employing this novel methodology. We developed a camera logger that records full HD video through a wide-angle lens, providing high resolution footage with a greater field of view than other camera loggers. The main goal was to assess the suitability of this type of camera for the analysis of various aspects of the foraging ecology of a marine predator, the yellow-eyed penguin in New Zealand. Frame-by-frame analysis allowed accurate timing of prey pursuits and time spent over certain seafloor types. The recorded video footage showed that prey species were associated with certain seafloor types, revealed different predator evasion strategies by benthic fishes, and highlighted varying energetic consequences for penguins pursuing certain types of prey. Other aspects that could be analysed were the timing of breathing intervals between dives and observe exhalation events during prey pursuits, a previously undescribed behaviour. Screen overlays facilitated analysis of flipper angles and beat frequencies throughout various stages of the dive cycle. Flipper movement analysis confirmed decreasing effort during descent phases as the bird gained depth, and that ascent was principally passive. Breathing episodes between dives were short (<1 s) while the majority of the time was devoted to subsurface scanning with a submerged head. Video data recorded on free-ranging animals not only provide a wealth of information recorded from a single deployment but also necessitate new approaches with regards to analysis of visual data. Here, we demonstrate the diversity of information that can be gleaned from video logger data, if devices with high video resolution and wide field of view are utilized.
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Technical Report
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