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Protected areas are a cornerstone for biodiversity conservation, and typically support more natural and undisturbed habitats compared to unprotected lands. The effect of protected areas on intra-specific ecological niche has been rarely investigated. Here, we explore potential differences in ecological niche properties of birds and mammals across protected and unprotected areas, and relate such differences to species traits. We combine two decades of survey data of birds and mammals from protected and unprotected areas, and apply robust matching to obtain a set of environmentally comparable protected and unprotected sites. Next, we calculate intra-specific niche volume change and habitat shift between protected and unprotected areas, and use generalized linear mixed models to explain these responses with species traits (habitat specialization, body mass, diet, and red list status). The majority of bird and mammal species (83% and 90%, respectively) show different habitat use when occurring within and outside protected areas, with the magnitude of this shift highly varying across species. A minority of species (16% of birds and 10% of mammals) do not change their niche volume nor shift their habitat between protected and unprotected areas. Variation in niche properties is largely unrelated to species traits. Overall, the varying ecological niche responses of birds and mammals to protected areas underscore that there is no universal niche-based response, and that niche responses to land protection are species-specific., (© 2022. The Author(s).)

A multitude of studies confirm that species have changed their distribution ranges towards higher elevations and towards the poles, as has been predicted by climate change forecasts. However, there is large interspecific variation in the velocity of range shifts. From a conservation perspective, it is important to understand which factors explain variation in the speed and the extent of range shifts, as these might be related to the species' extinction risk. Here, we study shifts in the mean latitude of occurrence, as weighted by population density, in different groups of landbirds using 40 years of line transect data from Finland. Our results show that the velocity of such density shifts differed among migration strategies and increased with decreasing body size of species, while breeding habitat had no influence. The slower velocity of large species could be related to their longer generation time and lower per capita reproduction that can decrease the dispersal ability compared to smaller species. In contrast to some earlier studies of range margin shifts, resident birds and partial migrants showed faster range shifts, while fully migratory species were moving more slowly. The results suggest that migratory species, especially long-distance migrants, which often show decreasing population trends, might also have problems in adjusting their distribution ranges to keep pace with global warming.

Recent shifts in phenology in response to climate change are well established but often poorly understood. Many animals integrate climate change across a spatially and temporally dispersed annual life cycle, and effects are modulated by ecological interactions, evolutionary change and endogenous control mechanisms. Here we assess and discuss key statements emerging from the rapidly developing study of changing spring phenology in migratory birds. These well-studied organisms have been instrumental for understanding climate-change effects, but research is developing rapidly and there is a need to attack the big issues rather than risking affirmative science. Although we agree poorly on the support for most claims, agreement regarding the knowledge basis enables consensus regarding broad patterns and likely causes. Empirical data needed for disentangling mechanisms are still scarce, and consequences at a population level and on community composition remain unclear. With increasing knowledge, the overall support ('consensus view') for a claim increased and between-researcher variability in support ('expert opinions') decreased, indicating the importance of assessing and communicating the knowledge basis. A proper integration across biological disciplines seems essential for the field's transition from affirming patterns to understanding mechanisms and making robust predictions regarding future consequences of shifting phenologies., (© 2011 The Authors. Biological Reviews © 2011 Cambridge Philosophical Society.)

A Poisson process is a commonly used starting point for modeling stochastic variation of ecological count data around a theoretical expectation. However, data typically show more variation than implied by the Poisson distribution. Such overdispersion is often accounted for by using models with different assumptions about how the variance changes with the expectation. The choice of these assumptions can naturally have apparent consequences for statistical inference. We propose a parameterization of the negative binomial distribution, where two overdispersion parameters are introduced to allow for various quadratic mean-variance relationships, including the ones assumed in the most commonly used approaches. Using bird migration as an example, we present hypothetical scenarios on how overdispersion can arise due to sampling, flocking behavior or aggregation, environmental variability, or combinations of these factors. For all considered scenarios, mean-variance relationships can be appropriately described by the negative binomial distribution with two overdispersion parameters. To illustrate, we apply the model to empirical migration data with a high level of overdispersion, gaining clearly different model fits with different assumptions about mean-variance relationships. The proposed framework can be a useful approximation for modeling marginal distributions of independent count data in likelihood-based analyses.

Several bird species have advanced the timing of their spring migration in response to recent climate change. European short-distance migrants, wintering in temperate areas, have been assumed to be more affected by change in the European climate than long-distance migrants wintering in the tropics. However, we show that long-distance migrants have advanced their spring arrival in Scandinavia more than short-distance migrants. By analyzing a long-term data set from southern Italy, we show that long-distance migrants also pass through the Mediterranean region earlier. We argue that this may reflect a climate-driven evolutionary change in the timing of spring migration.

Aim: Recent evidence has shown changes in body size and shape of individuals, which are suggested to be a result of global warming caused by climate change. Here, we explored the spatiotemporal changes in wing length and body mass of 24 wintering bird species in Northern Europe and how these relate to temperature anomaly. Location: Finland and Sweden, Europe. Time Period: 50 years, 1970 to 2020. Major Taxa Studied: Birds, 24 species. Methods: We used site‐specific, long‐term winter ringing data containing wing length and body mass measurements from across Sweden and Finland for 24 bird species. We modelled wing length and body mass change over time, in relation to the spatioclimatic gradient and as response to temperature anomalies (of [i] the same winter as the ringing took place, [ii] the previous winter and [iii] the previous spring) by accounting for phylogenetic relatedness between species and their species‐specific responses to each predictor of interest. Results: We show that across all species, body size has decreased since the 1970s, with a negative relationship between wing length and temperature anomalies of previous winters, suggesting carry‐over effects likely linked to body size‐related survival or dispersal. Body mass was negatively related to the temperature anomaly of the same winter, indicating more immediate effects related to reduced fat reserves during mild winters. Main Conclusions: Our results highlight a climate‐driven decrease in body size across several species and its association with positive anomalies in winter temperature in the high latitudes. However, the responses are not spatially uniform and there is considerable species‐specific variation, emphasizing the importance of conducting multispecies studies when investigating responses to climate change. The mechanisms of decreasing wing length and body mass seem to differ and underline the immediate and carry‐over effects of temperature warming during the nonbreeding season. [ABSTRACT FROM AUTHOR]

The article offers information on the effect of changes in phenological synchrony on ecological communities. Topics discussed include climate change affecting global biodiversity, studying match-mismatch by model system of insectivorous birds and their prey, and changes in phenological synchrony affecting food distribution and competition for territories.

• Multi-species bird indicators increasingly consider site and species selection methods. • Strong spatial, seasonal and habitat biases are identified among bird indicators. • Statistical uncertainty is overlooked in several multi-species bird indicators. • Modelling of common annual random variation in indicator analyses is often missing. • Many indicators do not incorporate temporal autocorrelation or phylogenetic correlation. The current loss of biodiversity has been broadly acknowledged as the main cause of ecosystem change. To halt this trend, several international agreements have been made, and various biodiversity metrics have been developed to evaluate whether the targets of these agreements are being met. The process of developing good indicators is not trivial. Indicators should be able to synthesize and communicate our current knowledge, but they also need to meet both scientific and practical criteria. Since it would not be practical to monitor all species, indicators are mainly built on the monitoring of some well-known taxa, such as birds. Here we systematically review the wide spectrum of bird biodiversity indicators (hereafter indicators) available to: i) evaluate recent methodological advances; ii) identify current knowledge gaps jeopardizing indicator interpretation and use in guiding decision-making; and iii) examine challenges in their applicability across different spatial and temporal contexts. We pay particular attention to indicator characteristics such as site and species selection, spatial, seasonal and habitat coverage, and statistical issues in developing indicators and tools to tackle them, to provide specific recommendations for the future construction of indicators. Several methodological advances have recently been made to enhance the process of indicator development, including multiple ways to select sites and species to increase their robustness. However, we found that there are strong spatial, seasonal and habitat biases among the selected indicators. Most of them are from Europe, using mainly census data from the breeding season and typically covering farmland and forest habitats. The major challenges that we detected in their applicability were related to the modelling of the statistical uncertainty associated to the indicator. We recommend the use of quantitative methods in site and species selection procedures whenever possible. Current indicators should be expanded to areas outside Europe and to less studied habitats and should not neglect monitoring work outside the breeding season. Time-series analyses studying temporal trends and using multi-species data should in general account for temporal autocorrelation as well as for phylogenetic correlation. Multi-species hierarchical models are a good alternative for analysing and constructing indicators, but they need to include annual random effects allowing for unexplained annual variation in the average status of the community, i.e. the indicator target. Despite methodological and context-specific differences in the indicators reviewed, most of them seem to highlight the urgent need of devising strategic climate and conservation policies to improve the status and trends of biodiversity. [ABSTRACT FROM AUTHOR]