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Introduction
The aim of the Antarctic Research Trust (ART) is to conduct and support scientific research on Antarctic and sub-Antarctic animals in order to provide baseline data for adequate conservation measures.
Additional affiliations
Education
July 1990 - December 1993
Institute für Meereskunde, Universität Kiel
Field of study
- Foraging ecology of Emperor and King Penguins
Publications
Publications (138)
Recent advancements in deep learning and aerial imaging have transformed wildlife monitoring, enabling researchers to survey wildlife populations at unprecedented scales. Unmanned Aerial Vehicles (UAVs) provide a cost-effective means of capturing high-resolution imagery, particularly for monitoring densely populated seabird colonies. In this study,...
The use of animal-borne cameras enables scientists to observe behaviours and interactions that have until now, gone unseen or rarely documented. Researchers can now analyse prey preferences and predator-prey interactions with a new level of detail. New technology allows researchers to analyse prey features before they are captured, adding a new dim...
Aim
To understand the influence of Andean uplifts and glacial cycles on South American biodiversity, we delve into the population genetics and evolutionary history of a unique subantarctic island raptor specialised in exploiting marine food webs.
Location
Islands in Tierra del Fuego and Malvinas/Falklands.
Time period
Last glacial period to the p...
Intrinsic and extrinsic factors, such as bioerosion at nesting sites, regulate population dynamics and are relevant for the long-term conservation of penguins. Colony trends (between 2004–2022) were studied in a Magellanic penguin colony on Martillo Island, Beagle Channel, Argentina and compared between zones with contrasting degrees of erosion (hi...
Marine Protected Areas (MPAs) are crucial for conserving marine biodiversity, and assessing the effectiveness of boundaries in protecting marine species is essential. In the Southwest Atlantic Ocean, four MPAs have been created. In this study we evaluate the use of these MPAs by Southern Rockhopper Penguins (Eudyptes chrysocome) that nest at Isla d...
The Sooty Shearwater (Ardenna grisea) is a species facing global decline, nesting on southern hemisphere islands, and migrating to the northern hemisphere during the non-breeding season. Historical groundwork on Wollaston Island in Chile suggested a possible dispersion of breeding grounds along the seaward fringe of the Fuegian islands, including I...
The Sooty Shearwater ( Ardenna grisea ) is a species facing global decline, nesting on southern hemisphere islands, and migrating to the northern hemisphere during the non-breeding season. This study confirms the species ́ breeding presence on Isla de los Estados in the Fuegian archipelago, Argentina. Additionally, we present a preliminary evaluati...
Effective seabird management strategies rely on accurate population estimates, with previous methods typically employing ground counts of a target species. However, difficult and often inaccessible breeding habitats are now able to be explored due to recent technological advancements in Unoccupied Aerial Vehicles (UAVs). This study tested a novel a...
The observation of two types of plumage colour variation in erect-crested penguins (Eudyptes sclateri) on the Antipodes Island is reported.
Variation in the foraging niche and parental provisioning behaviors of breeding seabirds have the potential to affect population dynamics (e.g. foraging success, breeding productivity, and ultimately population size). We sampled blood plasma
of family’ groups (females, males, and chicks) of Magellanic penguins (Spheniscus magellanicus) from Martill...
Ruddy-headed goose Chloephaga rubidiceps has a migratory population that overwinters mainly in the Pampas region, Argentina, and breeds in Southern Patagonia. This population has decreased considerably, with less than 800 individuals remaining to date. We conducted the first assessment on the influence of environmental and anthropogenic-impact (win...
Seabirds coexist within colonies yet the role of conspecifics, whilst foraging is still poorly understood. In the 2019/20 and 2020/21 breeding seasons Magellanic penguins Spheniscus magellanicus and Gentoo penguins Pygoscelis papua were equipped with video loggers and GPS devices (n = 3 and n = 2, respectively) or only GPS devices (n = 11 and n = 2...
Anthropogenic climate change is resulting in spatial redistributions of many species. We assessed the potential effects of climate change on an abundant and widely distributed group of diving birds, Eudyptes penguins, which are the main avian consumers in the Southern Ocean in terms of biomass consumption. Despite their abundance, several of these...
Mercury pollution is a serious global environmental issue and the characterization of its distribution and its driving forces should be urgently included in research agendas. We report unusually high mercury (Hg) concentrations (>5 μg/g) along with stable isotopes values in feathers of southern rockhopper penguins (Eudyptes chrysocome) from colonie...
Intraspecific competition for food resources has the potential to be high for central-place foragers such as penguins and can result in spatial and dietary foraging niche segregation among individuals of the same species. We sampled adults, chicks, and juvenile individuals' whole blood from three colonies of Magellanic penguins (Spheniscus magellan...
With the extinction of yellow-eyed penguins Megadyptes antipodes on mainland New Zealand predicted within the next few decades, identifying preventable causes of mortality during the juvenile dispersal period is critical. Between 2017 and 2019, we tracked 30 juvenile yellow-eyed penguins during their post-fledging dispersal to determine their dispe...
The Ruddy-headed Goose (Chloephaga rubidiceps) has two separate populations: one sedentary, which resides in the Falkland/Malvinas Islands and one migratory that overwinters mainly in the
Pampas region (Argentina) and breeds in Southern Patagonia (Argentina and Chile). The migratory population has decreased considerably to less than 800 individuals...
Ruddy-headed goose Chloephaga rubidiceps has a migratory population that overwinters mainly in the Pampas region, Argentina, and breeds in Southern Patagonia. This population has decreased considerably, with less than 800 individuals remaining to date. We conducted the first assessment on the influence of environmental and anthropogenic impact (win...
Mechanisms promoting coexistence between closely related species are fundamental for maintaining species diversity. Mechanisms of niche differentiation include allochrony which offsets the peak timing of resource utilisation between species. Many studies focus on spatial and temporal niche partitioning during the breeding season, few have investiga...
Penguins accumulate mercury due to their long-life span together with their high trophic position. We sampled adult and juveniles' feathers from three colonies of Spheniscus magellanicus from Tierra del Fuego along an inshore-offshore corridor. We integrated toxicological information (mercury concentrations) and foraging biomarkers (δ¹³C, δ¹⁵N) int...
Understanding the spatial distribution of seabirds contributes to comprehending their ecological requirements and dispersion patterns. We studied the at-sea distribution of female Southern Rockhopper Penguins (Eudyptes chrysocome (J.R. Forster, 1781)) at Isla de los Estados colony during the early chick-rearing period. We used a clustering analysis...
Aim
Delimiting recently diverged species is challenging. During speciation, genetic differentiation may be distributed unevenly across the genome, as different genomic regions can be subject to different selective pressures and evolutionary histories. Reliance on limited numbers of genetic markers that may be underpowered can make species delimitat...
Static (fixed‐boundary) protected areas are key ocean conservation strategies, and marine higher predator distribution data can play a leading role toward identifying areas for conservation action. The Falkland Islands are a globally significant site for colonial breeding marine higher predators (i.e., seabirds and pinnipeds). However, overlap betw...
Mercury is a widely available pollutant associated with negative effects on wildlife, especially top predators. Here, we characterized the mercury concentrations in feathers of Striated Caracara Phalcoboenus australis on Isla de los Estados (Argentina). With feather mercury levels averaging 26.3 mg/kg, this population has the highest mean feather m...
Magellanic penguins (Spheniscus magellanicus) disperse widely during winter and are a major consumer of marine resources over the Patagonian Shelf. Magellanic penguins were equipped with geolocators at Martillo Island in late February- early March 2017 and recaptured at the beginning of the next breeding season to recover the devices and to collect...
Los movimientos que realizan los individuos son relevantes para diversos procesos demográficos. Los individuos jóvenes, debido a su mayor movilidad, son claves para la conectividad entre poblaciones, y estudiarlos resulta fundamental para entender las dinámicas poblacionales. El carancho austral (Phalcoboenus australis) es una especie no migratoria...
Animals constantly test the borders of their own ecological niche and tend to expand their range, which is now additionally challenged by global climate change. Following human exploitation throughout the Southern Ocean in the 19th and the beginning of the 20th century, numbers of King Penguin breeding pairs have increased and former breeding sites...
Avian orthoavulavirus 1 (AOaV‐1) causes Newcastle disease, one of the most important and contagious infections in poultry, where migratory birds can play a key role as a reservoir. Seven hundred and seven serum samples were collected from five penguin species (King, Magellanic, Gentoo, Chinstrap, and Adelie penguins) in the Antarctic and Sub‐Antarc...
Inter-annual variations in the diets of seabirds are often a reflection of resource availability with population dynamics and community structure implications. We investigated Magellanic penguin´s trophic niche during the pre-molt stage across six years from 2009 and 2013 to 2017 at Martillo Island, Beagle Channel, Argentina, using carbon and nitro...
Stable isotopes raw data. Corrected δ15N, δ13C and C/N ratio is reported.
Optimal foraging theory predicts an inverse relationship between the availability of preferred prey and niche width in animals. Moreover, when individuals within a population have identical prey preferences and preferred prey is scarce, a nested pattern of trophic niche is expected if opportunistic and selective individuals can be identified. Here,...
Marine top predators living in sympatry tend to use their environment differentially, thereby reducing niche overlap. Magellanic penguins (Spheniscus magellanicus) and gentoo penguins (Pygoscelis papua) coexist at Martillo Is., Argentina. During the 2014, 2015 and 2017 breeding seasons a total of thirty-one Magellanic and eleven gentoo penguins wer...
Ruddy-headed Goose Chloephaga rubidiceps is the smallest of the five South American sheldgeese and has two separate populations: one sedentary, which resides in the Malvinas/Falkland Islands and one migratory that overwinters mainly in the Pampas region, Argentina and breeds in Southern Patagonia. The Ruddy-headed Goose’s continental population has...
Aim
Marine protected areas can serve to regulate harvesting and conserve biodiversity. Within large multi‐use MPAs, it is often unclear to what degree critical sites of biodiversity are afforded protection against commercial activities. Addressing this issue is a prerequisite if we are to appropriately assess sites against conservation targets. We...
The Retrospective Analysis of Antarctic Tracking Data (RAATD) is a Scientific Committee for Antarctic Research project led jointly by the Expert Groups on Birds and Marine Mammals and Antarctic Biodiversity Informatics, and endorsed by the Commission for the Conservation of Antarctic Marine Living Resources. RAATD consolidated tracking data for mul...
Southern Ocean ecosystems are under pressure from resource exploitation and climate change1,2. Mitigation requires the identification and protection of Areas of Ecological Significance (AESs), which have so far not been determined at the ocean-basin scale. Here, using assemblage-level tracking of marine predators, we identify AESs for this globally...
The Retrospective Analysis of Antarctic Tracking Data (RAATD) is a Scientific Committee for Antarctic Research project led jointly by the Expert Groups on Birds and Marine Mammals and Antarctic Biodiversity Informatics, and endorsed by the Commission for the Conservation of Antarctic Marine Living Resources. RAATD consolidated tracking data for mul...
Abstract Population connectivity is driven by individual dispersal potential and modulated by natal philopatry. In seabirds, high vagility facilitates dispersal yet philopatry is also common, with foraging area overlap often correlated with population connectivity. We assess the interplay between these processes by studying past and current connect...
An amendment to this paper has been published and can be accessed via a link at the top of the paper.
The dispersal of penguins during the non-breeding period is a critical period that can affect breeding success and survival in the following season. Thus, knowledge of penguin foraging ecology during this energy-intensive period is crucial to understand their responses to ecosystem variability. We recorded winter dispersal of Magellanic penguins Sp...
Penguins are good indicators of environmental changes and respond to oceanographic conditions within their foraging grounds. We studied adult and juvenile Magellanic penguin (Spheniscus magellanicus) trophic niches using stable carbon (13C) and nitrogen (15N) isotopes and determined their feather mercury (Hg) concentrations. We sampled feathers d...
The Patagonian Shelf Large Marine Ecosystem supports high levels of biodiversity and endemism and is one of the most productive marine ecosystems in the world. Despite the important role marine predators play in structuring ecosystems, areas of high diversity where multiple predators congregate remains poorly known on the Patagonian Shelf. Here, we...
Since at least the middle-Miocene, the Antarctic Polar Front (APF) and the Subtropical Front (STF) appear to have been the main drivers of diversification of marine biota in the Southern Ocean. However, highly migratory marine birds and mammals challenge this paradigm and the importance of oceanographic barriers. Eudyptes penguins range from the An...
Since at least the middle-Miocene, the Antarctic Polar Front (APF) and the Subtropical Front (STF) appear to have been the main drivers of diversification of marine biota in the Southern Ocean. However, highly migratory marine birds and mammals challenge this paradigm and the importance of oceanographic barriers. Eudyptes penguins range from the An...
El cauquén colorado (Chloephaga rubidiceps) es una especie que se encuentra en peligro crítico de extinción en la Argentina y Chile. Con el fin de proporcionar la primera documentación de la migración de esta especie, 6 adultos de cauquén colorado fueron equipados, durante 2015 y 2016, con transmisores solares satelitales (PTT Solares) y rastreados...
El cauquén colorado (Chloephaga rubidiceps) es una especie que se encuentra en peligro crítico de extinción en la Argentina y Chile. Con el fin de proporcionar la primera documentación de la migración de esta especie, 6 adultos de cauquén colorado fueron equipados, durante 2015 y 2016, con transmisores solares satelitales (PTT Solares) y rastreados...
Breeding status directly affects the at-sea behaviour of seabirds, resulting in marked differences between breeding and non-breeding birds. In this study, we report for the first time the foraging and diving behaviour of coexisting incubating, courting and non-breeding King Penguins (Aptenodytes patagonicus) at a recently established colony in Tier...
Knowing the spatial scales at which effective management can be implemented is fundamental for conservation
planning. This is especially important for mobile species, which can be exposed to threats across large areas, but
the space use requirements of different species can vary to an extent that might render some management
approaches inefficient....
Knowing the spatial scales at which effective management can be implemented is fundamental for conservation planning. This is especially important for mobile species, which can be exposed to threats across large areas, but the space use requirements of different species can vary to an extent that might render some management approaches inefficient....
Environmental changes often affect the persistence of species or populations at different spatial and temporal scales. Thus, species must either adapt to these changes or experience negative impacts at the individual or population levels. Southern Rockhopper Penguins Eudyptes chrysocome are distributed throughout the Southern Ocean and have experie...
Migratory species often roam vast distances bringing them into contact with diverse conditions and threats that could play significant roles in their population dynamics. This is especially true if long-range travels occur within crucial stages of a species’ annual life-cycle. Crested penguins, for example, usually disperse over several hundreds of...
The Upland Goose (Chloephaga picta picta) is a migratory species of South America, which breeds from September to April in Patagonia (Argentina and Chile) and winters from May to September in the southern Pampas (Argentina). Despite some protection in both countries, this species is still persecuted and large numbers are killed by unregulated hunti...
Environmental changes often affect the persistence of species or populations at different spatial and temporal scales. Thus, species must either adapt to these changes or experience negative impacts at the individual or population levels. Southern Rockhopper Penguins Eudyptes chrysocome are distributed throughout the Southern Ocean and have experie...
Marine Spatial Planning (MSP) is becoming a key management approach throughout the world. The process includes the mapping of how humans and wildlife use the marine environment to inform the development of management measures. An integrated multi-species approach to identifying key areas is important for MSP because it allows managers a global repr...
Migratory species often roam vast distances bringing them into contact with diverse conditions and threats that could play significant roles in their population dynamics. This is especially true if long-range travels occur within crucial stages of a species’ annual life-cycle. Crested penguins, for example, usually disperse over several hundreds of...
Migratory species often roam vast distances bringing them into contact with diverse conditions and threats that could play significant roles in their population dynamics. This is especially true if long-range travels occur within crucial stages of a species’ annual life-cycle. Crested penguins, for example, usually disperse over several hundreds of...
El Cauquén Colorado (Chloephaga rubidiceps) es un ave endémica de Sudamérica y es la especie más pequeña del género Chloephaga. Si bien las tres especies de cauquenes migratorios son motivo de preocupación, el estado de la población continental del Cauquén Colorado es particularmente alarmante debido a su rango de distribución restringido y a su pe...
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...
Studies of the at-sea distribution and trophic ecology of penguins are essential to understand their role in the broader marine food web. Magellanic Penguins Spheniscus magellanicus have a wide distribution and their foraging behaviour varies across breeding sites and between sexes, among others. In this study, we characterised the at-sea areas, th...
Ten Humboldt (Spheniscus humboldti) and eight Magellanic Penguins (S. magellanicus) were successfully equipped with satellite transmitters in March 2009 on Islotes Puñihuil in central south-Chile to follow their post-moult dispersal. Overall, Humboldt Penguins could be followed for a mean period of 49 ±18 days (range: 25–93) and Magellanic Penguins...
Detailed knowledge of the migratory strategies is important to understand the ecology and
evolution of migration and the conservation of migratory birds The Argentinean federal government
declared sheldgeese (Chloephaga spp.) pests in 1930, claiming that they reduce crop yield. Currently
sheldgeese have suffered severe reductions in their populatio...
Cumulative human impacts across the world's oceans are considerable. We therefore examined a single model taxonomic group, the penguins (Spheniscidae), to explore how marine species and communities might be at risk of decline or extinction in the southern hemisphere. We sought to determine the most important threats to penguins and to suggest means...
Most studies concerning the foraging ecology of marine vertebrates are limited to breeding adults, although other life history stages might comprise half the total population. For penguins, little is known about juvenile dispersal, a period when individuals may be susceptible to increased mortality given their naïve foraging behaviour. Therefore, w...
Worldwide marine protected areas (MPAs) have been designated to protect marine resources, including top predators such as seabirds. There is no conclusive information on whether protected areas can improve population trends of seabirds when these are further exploited as tourist attractions, an activity that has increased in past decades. Humboldt...
How closely related marine organisms mitigate competition for resources while foraging at sea is not well understood, particularly the relative importance of interspecific and intraspecific mitigation strategies. Using location and time–depth data, we investigated species-specific and sex-specific foraging areas and diving behaviour of the closely...
After an extended period of sporadic sightings of small numbers of king penguins at the Falkland Islands, they established themselves on Volunteer Point, situated at the north-east of the islands, by the late 1970s. By 1980, a small breeding population was present which yielded some 40 fledglings during that same year. Since 1991, the population ha...
Understanding the foraging behaviour of seabirds and its plasticity is vital to establish their role in marine food webs and their use as indicators of change in the availability of prey. The foraging behaviour of penguins is known to differ with locality, sex, stage of breeding and between years. We studied the diving behaviour of breeding Magella...
Various mitigation measures have been implemented to reduce incidental seabird mortality in longline
and trawl fisheries but little attention has been given to artisanal fishing. In the 2008/09 breeding season, during a study of foraging of Humboldt, Spheniscus humboldti, and Magellanic Penguins, S. magellanicus, breeding on Puñihuil islets, southe...
This study investigates the movements of Magellanic Penguins Spheniscus magellanicus breeding on Isla Martillo during the early chick-rearing period. Foraging paths were reconstructed using GPS loggers that registered the penguins0 geographic position, water temperature and depth at regular intervals. The relationship between penguins0 movements an...
We describe the mixed-species colony of Humboldt (Spheniscus humboldti) and Magellanic (S. magellanicus) penguins at Metalqui Island in Chiloe, southern Chile. The colony was visited on 8 December 2008 and nests (mostly dirt burrows) were individually checked for contents. Our survey included nearly 24% of the island's suitable nesting habitat for...
We describe the mixed-species colony of Humboldt (Spheniscus humboldti) and Magellanic (S. magellanicus) penguins at Metalqui Island in Chiloe, southern Chile. The colony was visited on 8 December 2008 and nests (mostly dirt burrows) were individually checked for contents. Our survey included nearly 24% of the island’s suitable nesting habitat for...
El pingüino de Humboldt (Spheniscus humboldti) y de Magallanes (S. magellanicus) se sobreponen sobre 1100 km a largo del Pacífico suroccidental y se ha hipotetizado mucho acerca de entrecruzamiento e hibridación entre ambas especies. Visitamos las islas de Puñihuil y Metalqui, en el sur de Chile (41–42° S), donde ambas especies forman colonias mixt...
The diving behaviour of female southern rockhopper penguins (Eudyptes chrysocome) was studied at Noir Island (54°30′S–73°00′W), Chile, in the southeast Pacific Ocean. This isolated island is located at
the edge of the continental shelf in an area where the Humboldt Current originates, and holds a population of more than 150,000
breeding pairs. On 1...
The breeding biology of the Magellanic Penguin (Spheniscus magellanicus), including the timing of laying, brooding and fledging, foraging trip lengths during incubation and brooding and diet in relation to breeding success, was investigated at Volunteer Beach in the north east of the Falkland Islands during the 2001/02 breeding season. Egg-laying d...
Humboldt (Spheniscus humboldti) and Magellanic penguins (S. magellanicus) overlap over 1,100 km along the Southeastern Pacific and much has been hypothesized about interbreeding. During the breeding season in November 2008 we visited Puñihuil and Metalqui islands, two mixed species colonies in southern Chile (41-42ºS). In this region, Magellanic an...
Magellanic penguin populations in the Falkland Islands may have decreased over the past decade. The post-breeding migration may be the period in which the birds are most vulnerable. To investigate this we equipped ten Magellanic Penguins after their moult at Seal Bay (51d̀38'S, 58d̀03'W), East Falkland, with satellite transmitters. The movements of...
A total of 22 magellanic penguins (Spheniscus magellanicus) from Isla Martillo in the Beagle Channel, Argentina, were successfully satellite tracked in 2004 (n=7), 2005 (n=7) and 2006 (n=8) to monitor their winter migration after moult. Only one magellanic penguin migrated northwards into the Pacific Ocean,
whereas all others remained in the Atlant...
The breeding biology of the King Penguin (Aptenodytes patagonicus) has been investigated in detail at sites across its circum-subantarctic range, except at its most temperate location, the Falkland Islands. Aspects of the breeding biology of King Penguins, including timing of laying, brooding and fledging and the length of shifts during incubation...
We used Argos satellite transmitters to monitor the movement and oceanographic habitats
used by rockhopper penguins Eudyptes chrysocome chrysocome during their winter dispersal
from Staten Island, Argentina, for 2002 (n = 10) and 2003 (n = 15). In both years penguins concentrated
their activities to shallow and highly productive waters with tempera...
The breeding biology of the King Penguin (Aptenodytes patagonicus) has been investigated in detail at sites across its circum-subantarctic range, except at its most temperate location, the Falkland Islands. Aspects of the breeding biology of King Penguins, including timing of laying, brooding and fledging and the length of shifts during incubation...
Rockhopper penguins (Eudyptes chrysocome) breeding on Staten Island, Argentina, were satellite tracked in 2002 and 2003 during the onset of their winter migration. After their moult, the dispersal of 24 birds was monitored for a mean period of 50.0±40.3days. Birds travelled at a mean velocity of 3.1±1.1km/h. The mean minimum distance travelled was...
The diving behaviour of southern rockhopper penguins (Eudyptes c. chrysocome) was studied at two breeding sites in the Southwest Atlantic: the Falkland Islands and Staten Island, Argentina. Incubating and brooding birds were equipped with time-depth recorders to monitor their foraging activities. Rockhopper penguins from Staten Island started their...
The diving behaviour of king penguins (Aptenodytes patagonicus) was studied on the Falkland Islands, where a small population (ca. 300fledglings year–1) is located at the geographical limit of their breeding range. King penguins rearing newly hatched chicks were equipped with time-depth recorders before leaving for sea. In total, 20,175dives >3m we...
The breeding biology of 14 pairs of Gentoo Penguins Pygoscelis papua was studied at Volunteer Beach, Falkland Islands during 2001/02. Breeding commenced in October and the mean hatch date for the first-laid egg was 6 December ± four days. The brood period lasted 27 days, and chicks fledged from the first week of February onward. The sexes shared in...
The breeding biology of the Magellanic Penguin (Spheniscus magellanicus), including the timing of
laying, brooding and fledging, foraging trip lengths during incubation and brooding and diet in relation to breeding success, was investigated at Volunteer Beach in the north east of the Falkland Islands during the 2001/02 breeding season. Egg-laying d...
The breeding biology of 14 pairs of Gentoo Penguins Pygoscelis papua was studied at Volunteer Beach, Falkland Islands during 2001/02. Breeding commenced in October and the mean hatch date for the first-laid egg was 6 December ± four days. The brood period lasted 27 days, and chicks fledged from the first week of February onward. The sexes shared in...