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Age-related variation in foraging performance can result from both withinindividual change and selection processes. These mechanisms can only be disentangled by using logistically challenging long-term, longitudinal studies. Coupling a long-term demographic data set with high-temporalresolution tracking of 18 Adélie penguins (Pygoscelis adeliae, age 4–15 yrs old) over three consecutive annual cycles, we examined how foraging behaviour changed within individuals of different age classes. Evidence indicated within-individual improvement in young and middle-age classes, but a significant decrease in foraging dive frequency within old individuals, associated with a decrease in the dive descent rate. Decreases in foraging performance occurred at a later age (from 12–15 yrs old to 15–18 yrs old) than the onset of senescence predicted for this species (9–11 yrs old). Foraging dive frequency was most affected by the interaction between breeding status and annual life-cycle periods, with frequency being highest during returning migration and breeding season and was highest overall for successful breeders during the chick-rearing period. Females performed more foraging dives per hour than males. This longitudinal, full annual cycle study allowed us to shed light on the changes in foraging performance occurring among individuals of different age classes and highlighted the complex interactions among drivers of individual foraging behaviour.

A reply to: Monti, Flavio et al. (2022). "Evolutionary risks of osprey translocations". Science 376 (6592): 468-169. 10.1126/science.abo5970. The reply is attached to the online version of the original article.

Physiology can either be a product of or affect the behavior and ecology of individual animals. Blood plasma chemistry contains many components that are indicative of several aspects of a bird’s physiological state at the time of sampling. Plasma chemistry is routinely used in clinical settings. However, despite its potential application in ecological studies, few birds have published reference values for these parameters from wild populations. Here, we analyzed the blood plasma chemistry for 17 parameters in Short-toed Snake Eagles (Circaetus gallicus) captured in southern Spain. Most values did not differ between age classes and sexes. However, we found differences between our captive and wild populations of fledgling eagles. These differences arose primarily in parameters associated with nutritional condition, as we expected due to captive individuals being fed ad libitum prior to blood draws. We also compared urea levels and a body condition index with hatching date and found a much stronger relationship with urea than the body condition index. Our results demonstrate the necessity to obtain blood chemistry reference values from wild populations and not just captive individuals, and also illustrate how these parameters can complement other traditional data collected when handling birds in the field.

The transposon Mutator was first identified in maize, and is one of the most active mobile elements in plants. The Arabidopsis thaliana genome contains at least 200 Mutator-like elements (MULEs), which contain the Mutator-like transposase gene, and often additional genes. We have detected a novel type of MULEs in melon (CUMULE), which, besides the transposase, contains two ubiquitin-like specific protease-like sequences (ULP1). This element is not present in the observed location in some melon cultivars. Multiple copies of this element exist in the Cucumis melo genome, and it has been detected in other Cucurbitaceae species. Analysis of the A. thaliana genome revealed more than 90 CUMULE-like elements, containing one or two Ulp1-like sequences, although no evidence of mobility exists for these elements. We detected various putative transposable elements containing ULP1-like sequences in rice. The discovery of these MULEs in melon and Arabidopsis, and the existence of similar elements in rice and maize, suggest that a proteolytic function may be important for this subset of the MULE transposable elements.

Mixed-species colonies occur frequently, especially among seabirds, and may provide mutual benefits among associated species including antipredator advantages. The “protector” species in such associations may provide early warning signals or by aggressively defending their own nests, may expel predators from the area. We explored costs and benefits to Rockhopper Penguins (Eudyptes chrysocome) in relation to offspring production in both monospecific colonies and those mixed with Imperial Cormorants (Phalacrocorax atriceps) at Saunders Island (Falkland Islands), emphasizing differences in predation pressure. We considered behavioral responses of chicks (in creches), as well as differences in their nutritional ` condition, morphometric measurements, and survival compared among different breeding colonies. Our study revealed a paradox: High-quality adult penguins, those arriving early and occupying lower-elevation sites closer to the coast, produced better-nourished chicks earlier in the season. However, they averaged half the number of chicks fledged, compared to breeders that arrived later in the season. Late breeders were forced by unavailability of optimal habitat to nest in more elevated areas, forming mixed colonies with cormorants, which, in turn, provided them with protection from nest predators. This study provides an example of the role of luck in nature, and how it may compensate for differences in individual fitness.

The coronavirus disease 2019 (COVID-19) pandemic is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This pathogen has spread rapidly across the world, causing high numbers of deaths and significant social and economic impacts. SARS-CoV-2 is a novel coronavirus with a suggested zoonotic origin with the potential for cross-species transmission among animals. Antarctica can be considered the only continent free of SARS-CoV-2. Therefore, concerns have been expressed regarding the potential human introduction of this virus to the continent through the activities of research or tourism to minimise the effects on human health, and the potential for virus transmission to Antarctic wildlife. We assess the reverse-zoonotic transmission risk to Antarctic wildlife by considering the available information on host susceptibility, dynamics of the infection in humans, and contact interactions between humans and Antarctic wildlife. The environmental conditions in Antarctica seem to be favourable for the virus stability. Indoor spaces such as those at research stations, research vessels or tourist cruise ships could allow for more transmission among humans and depending on their movements between different locations the virus could be spread across the continent. Among Antarctic wildlife previous in silico analyses suggested that cetaceans are at greater risk of infection whereas seals and birds appear to be at a low infection risk. However, caution needed until further research is carried out and consequently, the precautionary principle should be applied. Field researchers handling animals are identified as the human group posing the highest risk of transmission to animals while tourists and other personnel pose a significant risk only when in close proximity (< 5 m) to Antarctic fauna. We highlight measures to reduce the risk as well as identify of knowledge gaps related to this issue.

The most common ecological response to climate change is the shifts in species distribution ranges. Nevertheless, landscape fragmentation compromises the ability of limited dispersal species to move following these climate changes. Building connected environments that enable species to track climate changes is an ultimate goal for biodiversity conservation. Here, we conducted an experiment to determine if electric power transmission lines could be transformed in a continental network of biodiversity reserves for small animals. We analysed if the management of the habitat located inside the base of the transmission electric towers (providing refuge and planting seedlings of native shrub) allowed to increase local richness of target species (i.e., small mammals and some invertebrates’ groups). Our results confirmed that by modifying the base of the electric transmission towers we were able to increase density and diversity of several species of invertebrates and small mammals as well as number of birds and bird species, increasing local biodiversity. We suggest that modifying the base of the electric towers would potentially facilitate the connection of fragmented populations. This idea would be easily applicable in any transmission line network anywhere around the world, making it possible for the first time to build up continental scale networks of connectivit

this data set includes measurements of breeding sucesses for booted eagles from a long-term in Doñana Natural Park in the South of Spain. Furtherdetails of fieldprocedures are provided in the article

their risk of collision. However, differences in efficacy between types of devices, and in some cases conflicting results, place in question the ability of these devices to reduce collision risk to birds. Here, we investigated the efficacy of three types of flight diverters in reducing avian collision with power lines: yellow spiral, orange spiral, and flapper, additionally we used unmarked spans as a control. We recorded bird collisions and estimated removal rates of bird casualties by scavengers in three different 400 kV transmission lines comprising 133 spans in southern Spain. A total of 131 dead birds from 32 species were found. The power line and the type of marker significantly affected avian mortality. The flapper flight diverter was responsible for a 70.2% lower mean avian mortality rate (95% Confidence Interval: 50e90%), followed by the orange spiral (mean ¼ 43.7%, CI ¼ 15.8 e71.6%) and the yellow spiral (mean ¼ 40.4%, CI ¼ 2.8e78%), compared to control spans. Flappers were the only marker that showed greatest reduction in relation to non-marked spans. The flapper flight diverter showed the highest reduction in mortality and the narrowest confidence interval when tested in different environmental conditions, and thus may serve as a better alternative to the more commonly used spiral flight diverters

1. The present biodiversity crisis has led to an increasing number of reintroduction programs, and this conservation method is likely to be increasingly used in the future, especially in the face of climate change. Many fundamental questions in population ecology are focused on the mechanisms through which populations escape extinction. 2. Population viability analysis (PVA) is the most common procedure for analyzing extinction risk. In the use of PVA to model the trajectories of reintroduced populations, demographic values are sometimes taken from other existing wild populations or even from individuals in captivity. 3. Density dependence in productivity is usually considered in viability models, but density‐dependent variation in age of first breeding is usually ignored. Nevertheless, age of first breeding has a buffering effect on population fluctuations and in consequence on population persistence. 4. We simulated the viability of Spanish Imperial Eagle (Aquila adalberti) and Osprey (Pandion haliaetus) populations using data from established and reintroduced populations in southern Spain. 5. Our results show that reduction in the age of first breeding is critical in the success of reintroductions of such long‐lived birds. Additionally, increases in productivity allow populations to growth at maximum rate. However, without considering variation in age of breeding, and the associated increasing overall productivity, reintroduced populations seem nonviable. 6. To ignore density dependence in age of breeding in PVA means that we are seriously limiting the potential of the model population to respond to fluctuations in density, thereby reducing its resilience and viability. Variation in age of first breeding is an important factor that must be considered and included in any simulation model involving long‐lived birds with deferred maturity.

To provide an easy and reliable work tool to identify the sex of Rockhopper Penguin (Eudyptes chrysocome) chicks, we weighed and measured 95 nestlings in the crèche phase during 24-31 January 2017 on the Falkland Islands, Argentina. Sex was subsequently determined using DNA analyses of blood from the same individuals. Significant differences were found in bill length (exposed culmen), bill depth and width, flipper length, and diagonal tarsus, but stepwise discriminant analysis showed bill length to be the best predictor for sex determination. Our model correctly classified 82.7% of males and 90.2% of females (overall correct classification 86.2%). Threshold bill length was 36.64 mm, with values above this point being males and values below being females. Therefore, it appears that measuring bill length is an easy, immediate, and accurate method to sex Rockhopper Penguins during the crèche phase.

The present biodiversity crisis has led to an increasing number of reintroduction programs, and this conservation method is likely to be increasingly used in the future, especially in the face of climate change. Many fundamental questions in population ecology are focused on the mechanisms through which populations escape extinction. 2. Population viability analysis (PVA) is the most common procedure for analyzing extinction risk. In the use of PVA to model the trajectories of reintroduced populations, demographic values are sometimes taken from other existing wild populations or even from individuals in captivity. 3. Density dependence in productivity is usually considered in viability models, but density‐dependent variation in age of first breeding is usually ignored. Nevertheless, age of first breeding has a buffering effect on population fluctuations and in consequence on population persistence. 4. We simulated the viability of Spanish Imperial Eagle (Aquila adalberti) and Osprey (Pandion haliaetus) populations using data from established and reintroduced populations in southern Spain. 5. Our results show that reduction in the age of first breeding is critical in the success of reintroductions of such long‐lived birds. Additionally, increases in productivity allow populations to growth at maximum rate. However, without considering variation in age of breeding, and the associated increasing overall productivity, reintroduced populations seem nonviable. 6. To ignore density dependence in age of breeding in PVA means that we are seriously limiting the potential of the model population to respond to fluctuations in density, thereby reducing its resilience and viability. Variation in age of first breeding is an important factor that must be considered and included in any simulation model involving long‐lived birds with deferred maturity.

The Osprey (Pandion haliaetus) is an emblematic example of conservation. Currently, the species is progressively recovering in population size and range after dramatic reductions as a consequence of human persecution and the use of pesticides in the nineteenth and twentieth centuries. Here, we analysed the population trend and productivity in relation to the nesting substrate (artificial structures or trees) and the protection status of the nest location (inside or outside protected areas) in the eastern German population of Ospreys. The Osprey population steadily grew during the study period (2000–2009), accompanied by the increased use of artificial structures for nesting, possibly due to the scarcity of suitable natural nest sites in the region. Pairs nesting in trees showed higher variance in productivity than those nesting on artificial supports during the study period. Further, the productivity recorded in Ospreys nesting on natural sites decreased during the study period, regardless of the protection status of the nest location, whereas it did not vary for pairs nesting on artificial structures. The productivity of Ospreys was also related to the protection status of the nest location since pairs breeding inside protected areas, either in natural or on artificial nest sites, showed higher productivity than pairs nesting outside protected areas. These findings suggest that the protection of the nest location and the type of substrate used for nesting are relevant factors underlying the breeding performance in this Osprey population and are therefore key to its management.