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The Serengeti ecosystem contains one of the most diverse bird assemblages in Africa. We present here a data set consisting of abundances of bird species in different habitats of the Serengeti ecosystem over a 87-yr time frame. This data set comprises 66,643 georeferenced occurrences for 568 species from 1929 to 2017. Most records contain feeding location, food source, distribution status, and observation locality. The records originate from three different but complementary methodologies: points, sites, and transects. The point method (bird species records 1929–2017) is based on ad hoc observations and includes rare species or those in special habitats. These points came from published records as well from the research program of A. R. E. Sinclair and colleagues. The site method (1966–2017) is based on structured observations at sites selected to represent specific habitats, and replicated within habitats and over time. At each site, birds were recorded by sight and sound over a radius of 50 m for 10 min. The transect method (1997–2011) is based on road transects covering different areas of the ecosystem. Road transects were traversed using a vehicle with observers travelling at 30 km/h. Bird species were those easily seen from a vehicle out to 50 m either side. As most transects were traversed multiple times, this method provides information on temporal change in abundance for a select set of species. No copyright restrictions apply to the use of this data set other than citing this publication.

Heterochrony, the change in the rate or timing of development between ancestors and their descendants, plays a major role in evolution. When heterochrony produces polymorphisms, it offers the possibility to test hypotheses that could explain its success across environments. Amphibians are particularly suitable to exploring these questions because they express complex life cycles (i.e. metamorphosis) that have been disrupted by heterochronic processes (paedomorphosis: retention of larval traits in adults). The large phenotypic variation across populations suggests that more complex processes than expected are operating, but they remain to be investigated through multivariate analyses over a large range of natural populations across time. In this study, we compared the likelihood of multiple potential environmental determinants of heterochrony. We gathered data on the proportion of paedomorphic and metamorphic palmate newts (Lissotriton helveticus) across more than 150 populations during 10 years and used an information‐theoretic approach to compare the support of multiple potential processes. Six environmental processes jointly explained the proportion of paedomorphs in populations: predation, water availability, dispersal limitation, aquatic breathing, terrestrial habitat suitability and antipredator refuges. Analyses of variation across space and time supported models based on the advantage of paedomorphosis in favourable aquatic habitats. Paedomorphs were favoured in deep ponds, in conditions favourable to aquatic breathing (high oxygen content), with lack of fish and surrounded by suitable terrestrial habitat. Metamorphs were favoured by banks allowing easy dispersal. These results indicate that heterochrony relies on complex processes involving multiple ecological variables and exemplifies why heterochronic patterns occur in contrasted environments. On the other hand, the fast selection of alternative morphs shows that metamorphosis and paedomorphosis developmental modes could be easily disrupted in natural populations.

Long‐term observational studies conducted at large (regional) spatial scales contribute to better understanding of landscape effects on population and evolutionary dynamics, including the conditions that affect long‐term viability of species, but large‐scale studies are expensive and logistically challenging to keep running for a long time. Here, we describe the long‐term metapopulation study of the Glanville fritillary butterfly (Melitaea cinxia) that has been conducted since 1991 in a large network of 4000 habitat patches (dry meadows) within a study area of 50 by 70 km in the Åland Islands in Finland. We explain how the landscape structure has been described, including definition, delimitation, and mapping of the habitat patches; methods of field survey, including the logistics, cost, and reliability of the survey; and data management using the EarthCape biodiversity platform. We describe the long‐term metapopulation dynamics of the Glanville fritillary based on the survey. There has been no long‐term change in the overall size of the metapopulation, but the level of spatial synchrony and hence the amplitude of fluctuations in year‐to‐year metapopulation dynamics have increased over the years, possibly due to increasing frequency of exceptional weather conditions. We discuss the added value of large‐scale and long‐term population studies, but also emphasize the need to integrate more targeted experimental studies in the context of long‐term observational studies. For instance, in the case of the Glanville fritillary project, the long‐term study has produced an opportunity to sample individuals for experiments from local populations with a known demographic history. These studies have demonstrated striking differences in dispersal rate and other life‐history traits of individuals from newly established local populations (the offspring of colonizers) versus individuals from old, established local populations. The long‐term observational study has stimulated the development of metapopulation models and provided an opportunity to test model predictions. This combination of empirical studies and modeling has facilitated the study of key phenomena in spatial dynamics, such as extinction threshold and extinction debt. The long‐term metapopulation study of the Glanville fritillary butterfly (Melitaea cinxia) that has been conducted since 1991 in a large network of 4,000 habitat patches (dry meadows) within a study area of 50 by 70 km in the Åland Islands in Finland. Here, we explain how the landscape structure has been described, including definition, delimitation and mapping of the habitat patches; methods of field survey, including the logistics, cost and reliability of the survey; and data management using the EarthCape biodiversity platform.

Background House dust mite (HDM) allergens constitute the most frequent cause of persistent allergic rhinitis and asthma. The symptoms vary throughout the year but typically peak in spring, autumn and (to a lesser extent) mid-winter. Methods We performed a 13-month, observational, multicentre survey of adult patients with a self-reported history of moderate-to-severe, poorly controlled, physician-diagnosed HDM respiratory allergy in three European countries (France, Italy and Spain). After screening and inclusion, 28 detailed, fortnightly telephone interviews were used to gather extensive data on the participants’ symptom prevalence and intensity, medical consultations, disease burden and medication use from late May 2012 to early July 2013. This report focuses on the disease burden. Results Of the 22,995 screened participants, 313 met the inclusion criteria and completed the post-inclusion questionnaire ( n  = 114 in Italy, 92 in France and 107 in Spain). The median time since the first symptoms of HDM allergy was ≥ 13 years in each country. A relevant minority of the participants suffered from symptoms of HDM allergy every day or almost every day of the year (14% in Italy, 46% in France and 37% in Spain). According to the fortnightly telephone interviews, the most frequently impacted disease burden variables were sleep, daytime tiredness and irritability, with the highest values in spring 2012, autumn 2012 and spring 2013 (mirroring symptom intensities). Professional activities were more affected than social activities. The burden data were heterogeneous: around a quarter of participants were strongly or very strongly affected but most of the remaining participants were only rarely bothered or not bothered. Conclusions In a 13-month, fortnightly survey of patients in France, Italy and Spain with a self-reported history of moderate-to-severe, poorly controlled, HDM-induced allergic rhinitis and asthma, we found that a relevant minority of participants regularly reported a severe or very severe impact of their allergy on tiredness, sleep and professional activities (including time off work). The disease burden peaked in autumn and late spring.

Summary 1 Wildlife surveys usually focus on estimating population size, and management actions such as commercial harvesting, culling and poison baiting are referenced commonly to population size alone, without taking into account the way in which those animals are distributed. This paper outlines how point-based aerial survey data can be converted to continuous density surfaces using spatial analysis techniques. Using this approach, we describe and explore the spatial patterns of density of two species of kangaroos in an area exceeding 200 000 km2 in South Australia over a 26-year period. 2 Densities of red and western grey kangaroos were estimated in 2 km2 segments along aerial survey transect lines, yielding point density estimates. Universal kriging provided an unbiased interpolation of these data using the spatial autocorrelation structure described by the semi-variogram. The Getis statistic identified clusters of high and low kangaroo density. 3 Considerable year-to-year variation in the spatial patterns of kangaroo density was observed. In many cases, annual rates of increase over large areas were too high to be explained by vital rates alone, implying immigration from surrounding areas. These large shifts in distribution were occasionally to areas that had received better rainfall than the surrounding areas. For both species, there was no obvious local spatial autocorrelation pattern or clustering of kangaroo density beyond that described by average density and the present set of management regions, suggesting the latter are appropriate divisions for harvest management. 4 Data for both species fitted the power law relationship extremely well. During dry times, red kangaroos, but not western grey kangaroos, were more aggregated, supporting past ground observations at a fine spatial scale. 5 Synthesis and applications. Kriged density surfaces enable estimation of kangaroo density on individual properties, which are the management units at which harvest quotas or culling approvals are allocated. These estimates will be marked improvements over systematic sampling estimates when sampling intensity is low. Predictions of shifts in kangaroo distribution using rainfall or satellite imagery will allow more accurate allocation of harvest quotas. Similarly, predictions of more even kangaroo dispersion following high rainfall will allow managers to anticipate downturns in harvest rate.

We used a 12-year survey of butterflies in 24 parks in Marseille (South-East France), to highlight the overall decline of butterfly biodiversity (richness, abundance, diversity) in this Mediterranean city. This study confirms the importance of the urban gradient in the composition and structure of butterfly communities with a clear difference between the city centre and the outskirts. The study also highlights the preponderant role of local factors. While the distance from the natural environment remains a major factor, nectar resources and habitat diversity are local factors that can positively drive biodiversity. In contrast, management, as currently practised, has a negative effect on biodiversity. This implies that management, nectar resources and habitat diversity in parks are the key action levers at local scale. Thus, our results show that the response is not linear, from the most urban to the least urban, but seems to be closer to a patch/mosaic structure according to the importance of local factors. The long-term survey shows that butterfly communities show a simplified pattern: generally, parks on the outskirts tend to resemble those of the intermediate level and parks of the intermediate level tend to resemble those of the city centre. The long-term survey shows that butterfly communities have lost in complexity with the loss of Mediterranean species probably linked to the disappearance of their host plants. Finally, this long-term study suggests that it is possible to influence biodiversity through management with direct action in the management of green spaces.

Of the suite of species interactions involved in biotic resistance to species invasions, predation can have complex outcomes according to the theoretical and empirical framework of community ecology. In this study, we aimed to determine the likelihood of consumptive biotic resistance within fouling communities in four ports of central Chile. Notably, we examined the influence of micro- (> 1–2 mm, < 1–2 cm) and macro- (> 1–2 cm) predators, with a particular focus on their effects on non-indigenous species (NIS). Experimental and observational approaches were combined. An exclusion experiment was carried out over 4 months to examine predator effect on the early establishment of new assemblages on settlement panels. Later successional stages upon panels were examined over a total of 26 months and supported by rapid assessment surveys in the surrounding habitats. Community structure was significantly influenced by the exclusion treatments. Macropredators reduced the fouling biomass and abundance, although conflicting patterns emerged from the exclusion of both categories of predators. Altogether, predators reduced the abundance of most NIS and cryptogenic species, some of them being only observed when the two categories of predators were excluded—a pattern generally sustained over the long-term dynamics in community development. Our results show an effective consumptive biotic resistance, furthermore possibly dependent on predator size. Further work is however needed to determine the influence of the functional diversity of natural enemies on the efficiency of biotic resistance and its interplay with other biotic interactions (competition or mutualism). A comprehensive understanding of these processes should in turn help defining management strategies in a context of habitat modification and species loss.

Recent findings reported a significant decrease in abundance of two seahorse species (Hippocampus guttulatus and H. hippocampus) in the Ria Formosa lagoon (South Portugal) and no direct causes have been, so far, clearly identified. This study aimed to describe fluctuations in the local seahorse populations through monthly surveys over a course of a year, in order to identify some of the potential drivers behind the seasonal fluctuations. A total of six sites were chosen based on their habitat characteristics. The highest H. guttulatus abundances were recorded at sites with higher holdfast availability and depth ranging from 3 to 6 m, while H. hippocampus were observed at highest numbers in sites with lower holdfast availability and patchy distribution. In most sites, seahorse density decreased during the summer months (from May to August) and increased from August to December. Holdfast use changed across the surveyed sites, according to the respective habitat characteristics. This study identified environmental variables that influenced the abundance of seahorse population, i.e., holdfast availability, depth and temperature in the Ria Formosa lagoon, underlining the importance of monitoring populations over a course of no less than a year in order to avoid bias due to seasonal fluctuations. Identifying critical habitats will provide valuable information for local authorities in order to implement protective measures towards seahorse conservation.

Hosts have evolved two distinct defence strategies against parasites: resistance (which prevents infection or limit parasite growth) and tolerance (which alleviates the fitness consequences of infection). However, heritable variation in resistance and tolerance and the genetic correlation between these two traits have rarely been characterized in wild host populations. Here, we estimate these parameters for both traits in Leuciscus burdigalensis, a freshwater fish parasitized by Tracheliastes polycolpus. We used a genetic database to construct a full-sib pedigree in a wild L. burdigalensis population. We then used univariate animal models to estimate inclusive heritability (i.e. all forms of genetic and non-genetic inheritance) in resistance and tolerance. Finally, we assessed the genetic correlation between these two traits using a bivariate animal model. We found significant heritability for resistance (H = 17.6%; 95% CI: 7.2–32.2%) and tolerance (H = 18.8%; 95% CI: 4.4–36.1%), whereas we found no evidence for the existence of a genetic correlation between these traits. Furthermore, we confirm that resistance and tolerance are strongly affected by environmental effects. Our results demonstrate that (i) heritable variation exists for parasite resistance and tolerance in wild host populations, and (ii) these traits can evolve independently in populations.

In this paper we conducted a study referring to survey of background magnetic field in a laboratory of Electrical Engineering Faculty, where students carry out didactic activity. Based on three sets of measurements made in the 2017-2023 period, a characterization of the main field sources and the background magnetic field was performed. During this period, the power supply network has suffered some changes, and in terms of the used instruments, it was switched from spot measurement performed with commercial instruments to continuous long-term surveys performed with automatic survey systems made and calibrated by authors. In addition to considering the spatial variation of the magnetic field, the study determines and analyzes the temporal variations of the background magnetic field, namely the daily, weekly and monthly variability. Thus, a great temporal variability of the magnetic field was identified with the week days and even months, can be reached in the ratios between the magnetic field averages on the week days and on the months of the year of order 4/1 or even 5/1.