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Little penguins (Eudyptula minor) occur around most of New Zealand but the only systematic regional surveys have been carried out in Otago (1991-92, 2013) and Banks Peninsula (2000-02). This is the first national effort to map the location of their colonies and attempt to estimate penguin numbers. Little penguins are not evenly distributed around New Zealand. They are more common in eastern New Zealand than in the west. In the east of the North Island they are common in the Bay of Plenty north, but there are just a few small colonies south of Napier with only one known colony in the Wairarapa. In the eastern South Island, little penguins are (or were) numerous on Motunau Island, Banks Peninsula and Otago, but rare in eastern Marlborough and south Canterbury. Along New Zealand’s western shores, colonies tend to be smaller and more widely dispersed; even in those areas where little penguins are most common (Far North, Auckland, Taranaki, Wellington, Buller and Okarito). Little penguins are common on both sides of Cook Strait but uncommon in Fiordland and Southland. The southernmost colonies are on Stewart Island where they are thought to be common although the region is poorly surveyed. At the Chatham Islands their distribution is tolerably well known but not their numbers. We will discuss the role both land-based and sea-based threats may have had on influencing the distribution of little penguins. Presented at the 10th International Penguin Conference, Dunedin, New Zealand, August 2019

Little penguins (Eudyptula minor) occur around most of New Zealand but the only systematic regional surveys have been carried out in Otago (1991-92, 2013) and Banks Peninsula (2000-02). This is the first national effort to map the location of their colonies and attempt to estimate penguin numbers. Little penguins are not evenly distributed around New Zealand. They are more common in eastern New Zealand than in the west. In the east of the North Island they are common in the Bay of Plenty north, but there are just a few small colonies south of Napier with only one known colony in the Wairarapa. In the eastern South Island, little penguins are (or were) numerous on Motunau Island, Banks Peninsula and Otago, but rare in eastern Marlborough and south Canterbury. Along New Zealand’s western shores, colonies tend to be smaller and more widely dispersed; even in those areas where little penguins are most common (Far North, Auckland, Taranaki, Wellington, Buller and Okarito). Little penguins are common on both sides of Cook Strait but uncommon in Fiordland and Southland. The southernmost colonies are on Stewart Island where they are thought to be common although the region is poorly surveyed. At the Chatham Islands their distribution is tolerably well known but not their numbers. We will discuss the role both land-based and sea-based threats may have had on influencing the distribution of little penguins. Presented at the 10th International Penguin Conference, Dunedin, New Zealand, August 2019

International audience; The density and distribution of Westland Petrel burrows was assessed over a 12-year period (2007–2019). During that time, burrow densityincreased while occupancy remained stable, commensurate with an annual population growth rate of 1.022 (95% confidence interval:0.971–1.076), as estimated using mark recapture data. From our surveys, we estimated a 2019 baseline population of ~6 200 breeding pairsand a world population of 13 800–17 600 individuals, covering around 95% of the population. Transects were conducted to establish thelocation and density of 17 petrel sub-colonies in rugged, untracked terrain in Paparoa National Park, West Coast, New Zealand. Major stormsin 2014–2018 caused widespread treefall and landslides, destroying breeding habitat throughout the species’ breeding range. Demographiceffects of the major and ongoing habitat loss may continue in the medium to long term, as birds re-establish burrows and partnershipsfollowing loss of their habitat. Our study illustrates the complex effects of climate-related disruption on the biology of a long-lived species.With a single nesting area in the West Coast region, climate change will likely have an ongoing influence on the species’ global population,since an increase in the frequency of severe weather events, including ex-tropical cyclones, is expected. However, current indications suggestthat the species has some flexibility to adapt and to occupy new areas following habitat disturbance.

International audience; The use of long-term ecological datasets to explore the importance of the effects of environmental variability onhigher predator populations has been focused mainly on high-latitude areas. We modeled the population dynamics ofthe Westland Petrel (Procellaria westlandica), which spends its time mostly in subtropical waters during both breedingand the interbreeding migration across the Pacific Ocean. We found that the population has slowly increased since theearly 1970s, a result of high adult survival, high fecundity (0.6 of all eggs laid survived to fledge) and moderate meanage at first return to the colony (7.7 yr; a recruitment age typical for this genus), strong recruitment rate of juveniles,and negligible emigration. The modeled population trends were supported by similar rates of increase in nestoccupancy since 2001 and nest density since 2007. Annual adult survival for breeders was the same for both sexes(0.954, 95% CI: 0.918–0.975) and constant across years. However, nonbreeders had lower survival rates than breeders,and, among nonbreeders, males tended to survive better (0.926, 95% CI: 0.917–0.934) than females (0.917, 95% CI:0.900–0.931). Breeders transitioned to the nonbreeding state at a rate of 0.232 and nonbreeders to the breeding stateat a rate of 0.295. Sea-surface temperature anomalies had a negative effect on adult survival during the breedingperiod and a positive effect on survival outside the breeding season. Local marine productivity as measured by fisherycatches was strongly correlated with adult survival: Years with a greater fish catch were also years of higher adultsurvival. Despite many threats operating throughout the breeding and foraging range of Westland Petrels, it appearsthat marine environmental change is a strongly influential factor for the species, with uncertainty in population growthdue to predicted increases in sea-surface temperature in the future.

We propose that the Kiwi visual system has undergone adaptive regression evolution driven by the trade-off between the relatively low rate of gain of visual information that is possible at low light levels, and the metabolic costs of extracting that information.