Investigations into climate influence on population dynamics of yellow‐eyed penguinsMegadyptes antipodes

Abstract

to chance. The models also suggested that fledgeling success increased in seasons that were slightly cooler and wetter than average. Modelling studies were also carried out on a historical dataset of penguin population variables in the 1930s. It was found that the population tended to increase in seasons that were warmer and drier than average. Average temperatures have risen and average precipitation levels have become highly variable in the study area during this time. Therefore, long term climate change in general, rather than the El Nino-Southern Oscillation events in particular, could be among the underlying causes of gradual decline in yellow-eyed penguin numbers.Keywords Megadyptes antipodes; yellow-eyed penguin population variables; climate variables; computer models; causal link; climate change Abstract Since 1980, the yellow-eyed penguin Megadyptes antipodes has had three seasons of poor breeding success or low adult survival. Causes for poor seasons are not identified but could be related to climate -in particular, the El Nino-Southern Oscillation event, which affects ocean currents and climate over the penguins' range. We carried out an exploratory analysis to determine whether fluctuations in penguin population variables were correlated with fluctuations in climate variables. Population variables across breeding areas showed consistently strong correlations with rainfall and sea surface temperature. We modelled changes in climate variables and penguin population variables to test whether the effect could be explained as a chance correlation. Investigations using these models indicated that the observed relationship was unlikely to have been due

Neonatal Mortality in New Zealand Sea Lions (Phocarctos Hookeri ) at Sandy Bay, Enderby Island, Auckland Islands From 1998 to 2005

“…As a consequence, New Zealand sea lions are very likely to be susceptible to fluctuations of food resources as caused by El Niñ o/La Niñ a events or other climatic fluctuations. The effect of these events has not been investigated in New Zealand sea lion, but foraging patterns of other marine species that share the same latitudes have been studied in parallel with El Niñ o (low prey abundance) and La Niñ a (high prey abundance) events (Boyd et al, 1994;Peacock et al, 2000;Bowen et al, 2001;Soto et al, 2004). Availability of prey in the equatorial Pacific region varies considerably with the El Niñ o-Southern Oscillation (ENSO) (Barber and Chavez, 1983;Glynn, 1988).…”

Effects of climate change and fisheries bycatch on Southern Ocean seabirds: a review

“…Recently, several studies have investigated the effects of climate change (e.g. Peacock et al 2000, Barbraud & Weimerskirch 2001b, Sydeman et al 2001, Thompson & Ollason 2001, Ainley et al 2005, Jenouvrier et al 2005, Forcada et al 2006, Le Bohec et al 2008, Wolf et al 2010 and bycatch (e.g. Oro et al 1995, Tuck et al 2003, Cuthbert et al 2003, Votier et al 2004, Lewison et al 2004, Véran et al 2007, Frederiksen et al 2008) separately on seabirds worldwide, but few have addressed both issues simultaneously (Frederiksen et al 2004, Rolland et al 2009a).…”

Quantifying climate change impacts emphasises the importance of managing regional threats in the endangered Yellow-eyed penguin

“…As such the lagged correlation between SST and red cod abundance reported by Beentjes & Renwick (2001) also seems to be manifested in penguin body condition. This explains the relative importance of the corresponding covariate (i.e., sst_anomaly_minus1year) for survival rates (Tables 3A and 3B) and corresponds to findings of a previous analysis of climate variables on YEP numbers (Peacock, Paulin & Darby, 2000).…”

“…Most New Zealand penguin species including YEPs are believed to have undergone significant population declines in the past century, with climate change suspected to be playing a major role (e.g., Cunningham & Moors, 1994;Peacock, Paulin & Darby, 2000). At the same time, penguin populations are exposed to numerous anthropogenic threats (Trathan et al, 2015).…”