Andre Chiaradia

Phillip Island Nature Parks

As charismatic and iconic species, penguins can act as "ambassadors" or flagship species to promote the conservation of marine habitats in the Southern Hemisphere. Unfortunately, there is a lack of reliable, comprehensive, and systematic analysis aimed at compiling spatially explicit assessments of the multiple impacts that the world's 18 species o...

Understanding the spatial-temporal marine habits is crucial to conserving air-breathing marine animals that breed on islands and forage at sea. This study, focusing on little penguins from Phillip Island, Australia, employed tracking data to identify vital foraging areas during breeding season. Long-term data from sub-colonies and breeding stages w...

The COVID-19 pandemic and its lock-down measures have resulted in periods of reduced human activity, known as anthropause. While this period was expected to be favorable for the marine ecosystem, due to a probable reduction of pollution, shipping traffic, industrial activity and fishing pressure, negative counterparts such as reduced fisheries surv...

1. Protected areas are a widely adopted resource management strategy for mitigating the consequences of global change and preserve functioning ecosystems. Long-term species monitoring programmes, aided by bio-logging technology, provide insights into the extent and spatial variation of areas occupied by wild animals and inform conservation and mana...

Culturally dependent human social behaviours involving artificial light usage can potentially affect light pollution patterns and thereby impact the night-time ecology in populated areas, although to date this has not been examined globally. By analysing continuous (monthly), highly resolved, spatially explicit data on global night lights (Visible...

While the heterogeneity among individuals of a population is more and more documented, questions on the paths through which it arises, particularly whether it is linked to fixed heterogeneity or chance alone, are still widely debated. Here, we tested how individual quality, energy allocation trade-offs and environmental stochasticity define individ...

The COVID-19 pandemic and its lock-down measures have resulted in periods of reduced human activity, known as anthropause. While this period was expected to be favorable for the marine ecosystem, due to a probable reduction of pollution, shipping traffic, industrial activity and fishing pressure, negative counterparts such as the increased use of d...

1. Culturally dependent human social behaviours involving artificial light usage can potentially affect light pollution patterns and thereby impact the night-time ecology in populated areas, although to date this has not been examined globally. 2. By analysing continuous (monthly), highly resolved, spatially explicit data on global night lights (Vi...

While differences in foraging and reproductive success are well studied between seabird colonies, they are less understood at a smaller subcolony scale. Working with little penguins (Eudyptula minor) at Phillip Island, Australia, we used an automated penguin monitoring system and performed regular nest checks at two subcolonies situated 2 km apart...

Animal-borne tagging (bio-logging) generates large and complex datasets. In particular, accelerometer tags, which provide information on behaviour and energy expenditure of wild animals, produce high-resolution multi-dimensional data, and can be challenging to analyse. We tested the performance of commonly used artificial intelligence tools on data...

Persistent organic pollutants (POPs) are pervasive and a significant threat to the environment worldwide. Yet, reports of POP levels in Antarctic seabirds based on blood are scarce resulting in significant geographical gaps. Blood concentrations offer a snapshot of contamination within live populations, and have been used widely for Arctic and nort...

Foraging provides an integrative view of the effects of environmental variability on marine predators, from direct effects through increased energetic costs at sea to indirect effects through modification of prey accessibility. Using a 19 yr automated monitoring system of ~400 individuals (>45000 foraging trips), we investigated short-term and inte...

Foraging behaviour is crucial to breeding success for marine predators, including seabirds. Yellow-eyed penguins Megadyptes antipodes are central-place, predominantly benthic foragers around mainland New Zealand. The northern (mainland) population of this Endangered species is declining, with changes in the marine environment a suspected cause, par...

Reproductive performance typically improves with age, reaching a plateau at middle age and subsequently declining in older age classes (senescing individuals). Three potential non‐exclusive mechanisms can explain the improvement in reproductive performance with age: (1) selection (poor quality individuals are removed from the population with increa...

Changes in vegetation cover and dune mobility of Woolamai dune fields on the southeast coast of Australia were quantified based on a time-series of aerial imagery (1939 to 2020). Results showed that the dune fields have shifted from nearly all bare sand (with <5% vegetation cover) to a new quasi-equilibrium state, being almost fully stabilized by v...

Procellariiform use the sense of smell to find food in the middle of the ocean, to orient and navigate. For these seabirds, olfaction has been evidenced as they key cue for homing at night in burrow-nesting species. Penguins are phylogenetically closely related to Procellariiforms but very little is known on their use of odours for foraging. In add...

As extreme weather is expected to become more frequent with global climate change, it is crucial to evaluate the capacity of species to respond to short-term and unpredictable events. Here, we examined the effect of a strong storm event during the chick-rearing stage of little penguins (Eudyptula minor) from a mega colony in southern Australia. We...

Seabirds allocate different amounts of energy to reproduction throughout the breeding season, depending on the trade-off between their own needs and those of their chicks and/or changes in environmental conditions. Provisioning parents therefore modulate their foraging behaviour and diet accordingly. However, for diving seabirds, many studies have...

The extrinsic and intrinsic factors affecting differing reproductive strategies among populations are central to understanding population and evolutionary ecology. To evaluate whether individual reproductive strategies responded to annual patterns in marine productivity and age‐related processes in a seabird we used a long term (2003–2013), a conti...

McGuirk, M.T.; Kennedy, D.M.; Konlechner, T., and Chiaradia, A., 2021. Quantifying changes in surface elevation in conjunction with growth characteristics of incipient and foredune vegetation. Journal of Coastal Research, 37(1), 216–224. Coconut Creek (Florida), ISSN 0749-0208.Vegetation is critical for the initiation and growth of incipient dunes...

While globally distributed throughout the world's ecosystems, there is little baseline information on persistent organic pollutants (POPs) in marine environments in Australia and, more broadly, the Southern Hemisphere. To fill this knowledge gap, we collected baseline information on POPs in migratory short-tailed shearwaters (Ardenna tenuirostris)...

Detecting changes in marine food webs is challenging, but top predators can provide information on lower trophic levels. However, many commonly measured predator responses can be decoupled from prey availability by plasticity in predator foraging effort. This can be overcome by directly measuring foraging effort and success and integrating these in...

1. Changes in marine ecosystems are easier to detect in upper-level predators, like seabirds, which integrate trophic interactions throughout the food web. 2. Here, we examined whether diving parameters and complexity in the temporal organisation of diving behaviour of little penguins (Eudyptula minor) are influenced by sea surface temperature (SS...

Article Impact Statement: Safeguarding the future of penguins requires collaboration among scientists and policymakers and immediate, informed conservation action. Abstract More than half of the world's 18 penguin species are declining. We, the Steering Committee of the International Union for Conservation of Nature Species Survival Commission Peng...

More than half of the world's 18 penguin species are declining. We, the Steering Committee of the International Union for Conservation of Nature Species Survival Commission Penguin Specialist Group, determined that the penguin species in most critical need of conservation action are African penguin (Spheniscus demersus), Galápagos penguin (Sphenisc...

Penguins face a wide range of threats. Most observed population changes have been negative and have happened over the last 60 years. Today, populations of 11 penguin species are decreasing. Here we present a review that synthesizes details of threats faced by the world’s 18 species of penguins. We discuss alterations to their environment at both br...

Shearwaters and petrels (hereafter petrels) are highly adapted seabirds that occur across all the world’s oceans. Petrels are a threatened seabird group comprising 124 species. They have bet-hedging life histories typified by extended chick rearing periods, low fecundity, high adult survival, strong philopatry, monogamy and long-term mate fidelity...

There have been efforts around the globe to track individuals of many marine species and assess their movements and distribution, with the putative goal of supporting their conservation and management. Determining whether, and how, tracking data have been successfully applied to address real-world conservation issues is, however, difficult. Here, w...

Aim Animal movement is an important determinant of individual survival, population dynamics and ecosystem structure and function. Nonetheless, it is still unclear how local movements are related to resource availability and the spatial arrangement of resources. Using resident bird species and migratory bird species outside the migratory period, we...

Central-place foraging in large seabird colonies leads to high levels of intra-specific competition for food resources, often resulting in between-colony spatial segregation. However, little is known about within-colony variation in foraging behaviour that may arise from breeding locations. Using little penguins Eudyptula minor from a large colony...

High precision, high coverage DNA-based diet analysis tools allow great insight into the food web interactions of cryptic taxa. We used DNA fecal-metabarcoding to look for unrecorded taxa within the diet of a generalist central-placed predator, the little penguin Eudyptula minor. We examined 208 scats from 106 breeding pairs throughout August–Febru...

Under climate change, seabirds can provide a means to monitor rapid changes in the marine environment. An emerging approach uses fractal analysis to assess structural complexity in behavioural sequences, yet identifying how such complexity is affected by intrinsic and extrinsic parameters remains underexplored. Here, we examined how diving paramete...

Despite the increase of literature on seabird plastic ingestion in recent years, few studies have assessed how plastic loads vary according to different sampling methods. Most studies use necropsies of seabirds with a natural cause of death, e.g. beached or predated, to determine plastic loads and monitor marine debris. Sampling naturally dead seab...

Due to ongoing climate change, it is necessary to understand how ecosystems and food webs are affected by these environmental changes. As upper-level predators, seabirds’ behaviour provides a way to monitor changes occurring in the marine environment, but identifying how the complexity in the temporal structure of behaviour depend on intrinsic and...

Reproductive timing in many taxa plays a key role in determining breeding productivity ¹, and is often sensitive to climatic conditions ² . Current climate change may alter the timing of breeding at different rates across trophic levels, potentially resulting in temporal mismatch between the resource requirements of predators and their prey ³ . Thi...

Wildlife watching is an emerging ecotourism activity around the world. In Australia and New Zealand, night viewing of little penguins attracts hundreds of thousands of visitors per year. As penguins start coming ashore after sunset, artificial lighting is essential to allow visitors to view them in the dark. This alteration of the nightscape warran...

Restrictions on roaming Until the past century or so, the movement of wild animals was relatively unrestricted, and their travels contributed substantially to ecological processes. As humans have increasingly altered natural habitats, natural animal movements have been restricted. Tucker et al. examined GPS locations for more than 50 species. In ge...

Penguins are the most threatened group of seabirds after albatrosses. Despite being regularly captured in fishing gear, the threat to penguins, as a group, has not yet been assessed. We reviewed both published and grey literature to identify the fishing gear types that penguins are most frequently recorded in, the most impacted species and, for the...

The use of artificial light at night and its ecological consequences are increasing around the world. Light pollution can lead to massive mortality episodes for nocturnally active petrels, one of the most threatened avian groups. Some fledglings can be attracted or disoriented by artificial light on their first flights. Studies testing the effect o...

Little penguins (Eudyptula minor) have one of the widest geographic distributions among penguins, exposing them to variable ecological constraints across their range, which in turn can affect their foraging behaviour. Presumably, behavioural flexibility exists to allow animals to adapt to prevailing environmental conditions throughout their foragin...

One of the most critical phases in the life of petrels (Procellariiformes) is at fledging when young birds pass from parental dependence on land to an independent life at sea. To mitigate mortality at this time, rescue programs are implemented near breeding sites around the world, especially for birds grounded by artificial lights. We evaluated the...

Human activities drive environmental changes at scales that could potentially cause ecosystem collapses in the marine environment. We combined information on marine biodiversity with spatial assessments of the impacts of climate change to identify the key areas to prioritize for the conservation of global marine biodiversity. This process identifie...

Artificial lights at night cause high mortality of seabirds, one of the most endangered groups of birds globally. Fledglings of burrow-nesting seabirds, and to a lesser extent adults, are grounded by lights when they fly at night. We review the current state of knowledge of light attraction, identify information gaps and propose measures to address...

Most effects of environmental and climate variability on predator life-history traits and population dynamics result from indirect effects mediated through the food chain. There is growing evidence that wind strength might affect seabirds while foraging at sea. Here, we investigated the effect of wind speed on the foraging performance of a flightle...

This PDF file includes: fig. S1. Significance and magnitudes of observed environmental changes. fig. S2. Major contributors to fishing pressure. fig. S3. Identifying hot spots of marine biodiversity. table S1. Long-term, remote-sensing records of oceanographic features.

Visible light on Earth largely comes from the sun, including light reflected from the moon. Predation risk is strongly determined by light conditions, and some animals are nocturnal to reduce predation. Artificial lights and its consequent light pollution may disrupt this natural behavior. Here, we used 13 years of attendance data to study the effe...

Supplementary information reporting all steps during data analysis so anyone can execute the same analysis and obtain the same results. By reporting our analysis in a reproducible way, we hope that this single file can be useful to others by making all coding available.

Marine top and meso predators like seabirds are limited by the need to breed on land but forage on limited or patchily distributed resources at sea. Constraints imposed by such central-place foraging behavior change during breeding or even disappear outside the breeding period when there is no immediate pressure to return to a central place. Howeve...

Spatially scale-invariant Lévy walk (power-law) patterns seem common among animals that move continually during searching. Scaling-laws also describe well the spontaneous patterns of waiting times of sit-and-wait ambush predators, which show random ‘burstiness’ that appears scale-invariant across a broad set of scales. The occurrence of these scali...

Animal movement exhibits self-similarity across a range of both spatial and temporal scales reminiscent of statistical fractals. Stressors are known to induce changes in these statistical patterns of behavior, although the direction and interpretation of such changes are not always clear. We examined whether the imposition of known hydrodynamic dis...

Life-history strategies have evolved in response to predictable patterns of environmental features. In practice, linking life-history strategies and changes in environmental conditions requires comparable space-time scales between both processes, a difficult match in most marine system studies. We propose a novel spatio-temporal and dynamic scale t...

The wide geographic distribution of penguins (Order Sphenisciformes) throughout the Southern Hemisphere provided a unique opportunity to use a single taxonomic group as biomonitors of mercury among geographically distinct marine ecosystems. Mercury concentrations were compared among ten species of penguins representing 26 geographically distinct br...

The distribution of predators relative to specific abiotic and biotic factors within estuarine plume fronts is largely unexplored due to the lack of fine-scale temporal and spatial oceanographic data. Defining preferred foraging conditions of seabirds in these areas is critical to identifying important foraging habitats. Here, we use data obtained...

Marine animals forage in areas that aggregate prey to maximize their energy intake. However, these foraging 'hot spots' experience environmental variability, which can substantially alter prey availability. To survive and reproduce animals need to modify their foraging in response to these prey shifts. By monitoring their inter-annual foraging beha...

Unlike migratory seabirds with wide foraging ranges, resident seabirds forage in a relatively small range year-round and are thus particularly vulnerable to local shifts in prey availability. In order to manage their populations effectively, it is necessary to identify their key prey across and within years. Here, stomach content and stable isotope...

1. Summary Using body mass and breeding data of individual penguins collected continuously over 7 years (2002–2008), we examined carry-over effects of winter body mass on timing of laying and breeding success in a resident seabird, the little penguin (Eudyptula minor). The austral winter month of July consistently had the lowest rate of colony atte...

Light pollution is increasing around the world and altering natural nightscapes with potential ecological and evolutionary consequences. A severe ecological perturbation caused by artificial lights is mass mortalities of organisms, including seabird fledglings that are attracted to lights at night on their first flights to the sea. Here, we report...

Competition for food resources can result in spatial and dietary segregation among individuals from the same species. Few studies have looked at such segregations with the combined effect of sex and age in species with short foraging ranges. In this study we examined the 3D spatial use of the environment in a species with a limited foraging area. W...

Diet-related breeding failure in seabirds has been attributed to declines in key prey abundance, the quality of prey and overall prey availability. However, identifying which aspect of diet is responsible for reproductive failure is challenging due to the practicalities of measuring prey utilization and the actual availability and abundance of thos...

Reconstructing the diet of top marine predators is of great significance in several key areas of applied ecology, requiring accurate estimation of their true diet. However, from conventional stomach content analysis to recent stable isotope and DNA analyses, no one method is bias or error free. Here, we evaluated the accuracy of recent methods to e...

According to life-history theory, individuals optimize their decisions in order to maximize their fitness. This raises a conflict between parents, which need to cooperate to ensure the propagation of their genes but at the same time need to minimize the associated costs. Trading-off between benefits and costs of a reproduction is one of the major f...

We hypothesized that the catastrophic annual molt of penguins (Sphenisciformes) would lead to reduced intra-individual variation of mercury concentrations in body feathers. While mean mercury concentrations varied significantly among 8 penguin species, intra-individual variability did not differ among species and was three times lower than values o...

Animal behaviour exhibits fractal structure in space and time. Fractal properties in animal space-use have been explored extensively under the Lévy flight foraging hypothesis, but studies of behaviour change itself through time are rarer, have typically used shorter sequences generated in the laboratory, and generally lack critical assessment of th...

Supplementary Information

Detailed, long-term analysis reveals how a local penguin population recovered and stabilized by shifting its prey base in the aftermath of the near-total collapse of sardine stocks along the south Australian coast.

1. Nonlinear, parametric curve-fitting provides a framework for understanding diverse ecological and evolutionary trends (e.g. growth patterns and seasonal cycles). Currently, parametric curve-fitting requires a priori assumptions of curve trajectories, restricting their use for exploratory analyses. Furthermore, use of analytical techniques [nonli...

We studied foraging segregation between two different sized colonies of little penguins Eudyptula minor with overlapping foraging areas in pre-laying and incubation. We used stomach contents and stable isotope measurements of nitrogen (δ15N) and carbon (δ13C) in blood to examine differences in trophic position, prey-size and nutritional values betw...

The use of top predators as bio-platforms is a modern approach to understanding how physical changes in the environment may influence their foraging success. This study examined if the presence of thermoclines could be a reliable signal of resource availability for a marine top predator, the little penguin (Eudyptula minor). We studied weekly forag...

Breeding animals face important time and energy constraints when caring for themselves and their offspring. For long-lived species, life-history theory predicts that parents should favor survival over current reproductive attempts, thus investing more into their own maintenance than the provisioning of their young. In seabirds, provisioning strateg...

A complex interaction of biotic and abiotic factors influences animal foraging activity. It is often difficult to understand which factors may affect animals' foraging and how it is affected. For instance, whereas the effect of sexual dimorphism on foraging activity has been reported in several species, little is known of the complex interactions b...

Age-related changes in breeding performance are likely to be mediated through changes in parental foraging performance. We investigated the relationship of foraging performance with age in female little penguins at Phillip Island, Australia, during the guard phase of the 2005 breeding season. Foraging parameters were recorded with accelerometers fo...

According to life-history theory, individuals optimize their decisions in order to maximize their fitness. This raises a conflict between parents, which need to cooperate to ensure the propagation of their genes but at the same time need to minimize the associated costs. Trading-off between benefits and costs of a reproduction is one of the major f...

Chiaradia, A., Forero, M. G., Hobson, K. A., and Cullen, J. M. 2010. Changes in diet and trophic position of a top predator 10 years after a mass mortality of a key prey. – ICES Journal of Marine Science, 67: 1710–1720. After the disappearance of primary prey, seabirds exhibit gradually decreased breeding performance, and eventually the population...

DNA barcoding of faeces or stomach contents is an emerging approach for dietary analysis. We pyrosequenced mtDNA 16S markers amplified from faeces of captive little penguins (Eudyptula minor) to examine if recovered sequences reflect the proportions of species consumed. We also analysed wild little penguin faeces collected from 100 nests in southea...

Abstract: Links between changes in resource availability during the non-breeding season and reproductive performance are expected for an animal whose performance is dependent on pre-breeding body reserves (capital breeder) but less so for an animal that can rapidly restore body reserves during breeding (income breeder). We examined non-breeding sea...