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Territoriality entails demanding social interactions with competing individuals, typically males. Variation in quality of males can be predicted to affect the spatial arrangement of territories. We present a model aimed at understanding the spatial properties of territories on leks, where the presence of a hierarchy in a population of males leads to the clustering of individuals around high-ranking ‘hotshot’ males. The hierarchy results in a decrease in the number of nearest neighbors interacting directly with high-ranking males, with potential socio-sexual benefits for such males.

The western capercaillie Tetrao urogallus, hereafter capercaillie, is the largest galliform bird present in the boreal and montane forests of the Western Palearctic. Precise and accurate methods for estimating the number of individuals and/or their densities are crucial for the proper management of its free‐ranging populations. However, obtaining reliable estimates of the abundance of populations of wild species and, particularly, of birds is not a simple task. In the case of lek‐mating birds such as capercaillie, surveys are traditionally based on lek counts, that is, counts of calling males present in their mating areas: the leks. This study was carried out on the Pyrenees at six capercaillie leks where two different lek counting approaches were performed: hide‐based and walk‐based. The results were compared with those obtained from an estimate of minimum population size (MPE) derived from genotyping all faeces samples found in the lek area, and with a population size estimate derived from a genetic mark‐recapture model (N^o) of each capercaillie lek. The results of N^o were used to estimate the detection rate (D) of both lek count approaches. Our results show that traditional lek counts do not detect all male capercaillies since the detection rate was 0.34 (95% CI: 0.26–0.43) for hide‐ and 0.56 (95% CI: 0.43–0.68) for walk‐based lek counts. Our results suggest that the walk‐based lek counts were more efficient than the hide‐based ones, providing more accurate results compared to the N^o estimate. The combination of non‐invasive sampling with genetic mark‐recapture model was found to be the most reliable method for obtaining the N^o of leks given that traditional lek counts underestimate the number of capercaillie and, furthermore, can cause disturbance to the species at these sites.

1. Integrated visual displays that combine gesture with colour are nearly ubiquitous in the animal world, where they are shaped by sexual selection for their role in courtship and competition. However, few studies assess how multiple selection regimens operate on different components of these complex phenotypes on a macroevolutionary scale. 2. Here, we study this issue by assessing how both sexual and ecological selection work together to influence visual display complexity in the birds of paradise. 3. We first find that sexual dichromatism is highest in lekking species, which undergo more intense sexual selection by female choice, than non-lekking species. At the same time, species in which males directly compete with one another at communal display courts have more carotenoid-based ornaments and fewer melanin ornaments. 4. Meanwhile, display habitat influences gestural complexity. Species that dance in the cluttered understorey have more complex dances than canopy-displaying species. 5. Taken together, our results illustrate how distinct selection regimens each operate on individual elements comprising a complex display. This supports a modular model of display evolution, wherein the ultimate integrated display is the product of synergy between multiple factors that select for different types of phenotypic complexity.

The Southern Great Plains has been altered by conversion of native grassland to row-crop agriculture, which is considered the primary cause of declining lesser prairie-chicken (Tympanuchus pallidicinctus) populations. However, recent analyses indicate that direct loss of grassland has slowed while lesser prairie-chicken populations continue to decline, suggesting that remaining grasslands potentially suffer from degradation by various land uses (e.g., increased anthropogenic disturbance). Understanding the spatial ecology of lesser prairie-chickens relative to anthropogenic structures is important for conservation planning, habitat management, and infrastructure mitigation. We investigated effects of proximity to anthropogenic structures on home range and nest placement (second-order selection) and within home range space use (third-order selection) of radio-marked lesser prairie-chickens (n = 285) at 2 scales of selection using resource utilization functions and resource selection functions. We collected data from birds marked in the Mixed-Grass Prairie and Short-Grass Prairie ecoregions of Kansas, USA, from 15 March 2013 to 14 March 2016. Home range placement did not vary by region or season, and lesser prairie-chickens placed home ranges farther from powerlines and roads than would be expected at random. As distance increased from 0 to 3 km away from roads and powerlines, the relative probability of home range placement increased 1.66 and 1.54 times, respectively. Distance to powerline was the single most consistent variable negatively affecting nest placement. As the distance from powerline increased from 0 to 3 km, the relative probability of nest placement increased 2.19 times. Distance to oil well did not influence placement of home ranges or nests. When pooled across regions, lesser prairie-chickens exhibited behavioral avoidance of powerlines, roads, and oil wells within their home range. Lesser prairie-chickens, on average, used space at greater intensities within their home range farther from wells, powerlines, and roads than available. Across breeding season phases, we found no evidence of increased behavioral avoidance of anthropogenic structures during the nesting or brooding phases compared to the lekking or post-breeding phases. Within home range space use during the brooding phase was not related to powerlines, wells, or roads. Our results indicate that avoidance of anthropogenic structures may result in functional habitat loss and continued fragmentation of remaining grassland habitat. Reduction or elimination of anthropogenic development in quality lesser prairie-chicken habitat and concentrating new development in already altered areas that are avoided by lesser prairie-chickens and no longer considered available habitat may reduce continued habitat degradation throughout the species’ range and aid in population persistence.

In the long-tailed manakin (Chiroxiphia linearis), a long-lived tropical bird, early connectivity within a social network predicts male success an average of 4.8 years later. Long-tailed manakins have an unusual lek mating system in which pairs of unrelated males, at the top of complex overlapping teams of as many as 15 males, cooperate for obligate dual-male song and dance courtship displays. For as long as 8 years before forming stable \"alpha-beta\" partnerships, males interact with many other males in complex, temporally dynamic social networks. \"Information centrality\" is a network connectivity metric that accounts for indirect as well as shortest (geodesic) paths among interactors. The odds that males would rise socially rose by a factor of five for each one-unit increase in their early information centrality. Connectivity of males destined to rise did not change over time but increased in males that failed to rise socially. The results suggest that network connectivity is important for young males (ages 1-6) but less so for older males of high status (ages 10-15) and that it is difficult to explain present success without reference to social history.

Across portions of the western Great Plains in North America, natural fire has been removed from grassland ecosystems, decreasing vegetation heterogeneity and allowing woody encroachment. The loss of fire has implications for grassland species requiring diverse vegetation patches and structure or patches that have limited occurrence in the absence of fire. The lesser prairie-chicken (Tympanuchus pallidicinctus) is a declining species of prairie-grouse that requires heterogeneous grasslands throughout its life history and fire has been removed from much of its occupied range. Patch-burn grazing is a management strategy that re-establishes the fire-grazing interaction to a grassland system, increasing heterogeneity in vegetation structure and composition. We evaluated the effects of patch-burn grazing on lesser prairie-chicken space use, habitat features, and vegetation selection during a 4-year field study from 2014–2017. Female lesser prairie-chickens selected 1- and 2-year post-fire patches during the lekking season, ≥4-year post-fire patches during the nesting season, and year-of-fire and 1-year post-fire patches during post-nesting and nonbreeding seasons. Vegetation selection during the lekking season was not similar to available vegetation in selected patches, suggesting that lesser prairie-chickens cue in on other factors during the lekking season. During the nesting season, females selected nest sites with greater visual obstruction, which was available in ≥4-year post-fire patches; during the post-nesting season, females selected sites with 15–25% bare ground, which was available in the year-of-fire, 1-year post-fire, and 2-year post-fire patches; and during the nonbreeding season they selected sites with lower visual obstruction, available in the year-of-fire and 1-year post-fire patches. Because lesser prairie-chickens selected all available time-since-fire patches during their life history, patch-burn grazing may be a viable management tool to restore and maintain lesser prairie-chicken habitat on the landscape.

In many species, male lifespan is shorter than that of females, often attributed to sexual selection favouring costly expression of traits preferred by females. Coevolutionary models of female preferences and male traits predict that males can be selected to have such life histories; however, this typically requires that females also pay some costs to express their preferences. Here we show that this problem diminishes when we link coevolutionary models of costly mate choice with the idea of stamina. In our model, the most successful males are those who can combine high attendance time on a lek — or, more generally, tenacious effort in their display time budgets — with high viability such that they are not too strongly compromised in terms of lifespan. We find that an opportunistic female strategy, that minimizes its costs by mating with highly visible (displaying) males, often beats other alternatives. It typically resists invasion attempts of genotypes that mate randomly in the population genetic sense, as well as invasion of stricter ways of being choosy (which are potentially costly if choice requires e.g. active rejection of all males who do not presently display, or risky travel to lekking sites). Our model can produce a wide range of male time budgets (display vs. self-maintenance). This includes cases of alternative mating tactics where males in good condition spend much time displaying, while those in poor condition never display yet, importantly, gain some mating success due to females not engaging in rejection behaviours should these be very costly to express.Significance statementIn many species, males spend much time and energy on displaying to attract females, but it is not always clear what females gain from paying attention to male displays. The tradition in mathematical models attempting to understand the situation is to assume that random mating is the least costly option for females. However, random mating in the population genetic sense requires females to behave in a manner that equalizes mating success between displaying and non-displaying males, and here we point out that this is biologically unlikely. Opportunistically mating females can cause males to spend much of their time budgets displaying and will shorten male lifespans in a quality-dependent manner.

Anthropogenic features increasingly affect ecological processes with increasing human demand for natural resources. Such effects also have the potential to vary depending on the sex and age of an individual because of inherent behavioral and life experience differences. For the lesser prairie-chicken (Tympanuchus pallidicinctus), studies on male survival are limited because most previous research has been focused on females. To better understand patterns of lesser prairie-chicken survival in habitat with varying levels of anthropogenic infrastructure associated with oil and natural gas development, we monitored survival of 178 radio-tagged male and female lesser prairie-chickens in eastern New Mexico, USA, from 2013 to 2015. We examined the relationships of shrub cover, proximity to and density of anthropogenic features (i.e., utility poles), displacement of natural vegetation by anthropogenic features (i.e., area of roads and well pads), and individual demographics (i.e., sex, age) with lesser prairie-chicken survival. Furthermore, we categorized the probable cause of mortality and examined its relationship with oil and gas development intensity (indexed by utility pole density) within 1,425 m of an individual–s mortality site or final observed location. We predicted that survival would be lower for individuals exposed to greater levels of anthropogenic features, and that males and subadults would be more negatively affected than females and adults because of increased exposure to predators during the lekking season and naiveté. Relationships between survival and utility pole density, sex, and age were supported in our top-ranked models, whereas models including other anthropogenic and natural features (i.e., roads, well pads, shrub cover) received little support. We predicted a substantial decrease in adult and subadult male survival with increasing densities of utility poles. The relationship between survival and utility pole density for females was weaker and not as clearly supported as for males. We did not find a detectable difference in utility pole counts among probable mortality causes. Our findings highlight the importance of including male lesser prairie-chickens in research and conservation planning, and the negative effect that high densities of anthropogenic features can have on lesser prairie-chicken survival.

Tephritidae are an enormous threat to fruit and vegetable production throughout the world, causing both quantitative and qualitative losses. Investigating mating sequences could help to unravel mate choice dynamics, adding useful information to improve behaviour-based control strategies. We review current knowledge about sexual communication and related behaviours in Tephritidae, with a focus on six key agricultural pests: Anastrepha ludens, Bactrocera cucurbitae, Bactrocera dorsalis, Bactrocera oleae, Ceratitis capitata and Rhagoletis pomonella. We examine features and the role of male–male combat in lekking sites, cues affecting mating dynamics, and some fitness-promoting female behaviours that occur at oviposition sites [the use of oviposition marking pheromones (OMPs) and female–female fights for single oviposition sites]. We outline future perspectives and potential contributions of knowledge about sexual communication to Integrated Pest Management programs for tephritid pests. Sexually selected traits are frequently good indicators of male fitness and knowledge of sexual selection processes may contribute to the improvement of the sterile insect technique (SIT), to select genotypes with high reproductive success and to promote sexually selected phenotypes through mass-rearing optimization. Furthermore, males’ exposure to parapheromones, such as phenyl propanoids (PPs), ginger root oil and trimedlure can enhance the mating success of sterile flies used in SIT programs. PPs are also a powerful tool to improve reduced-risk monitoring dispensers and the male annihilation technique, with low side effects on non-target insects. Lastly, we outline the possibility to sensitise or train mass-reared parasitoids on OMPs during the pre-release phase, in order to improve their post-release performance in the field.

The population size of capercaille Tetrao urogallus in Scotland was estimated from annual counts of males at 151 known spring lek sites and 45 counts of males, females and their broods in August during the period 2010–2020, combined with published survival estimates. Population size declined from an estimated 580 birds (95% CL: 462–698) in 2011 to 304 (239–369) in 2020 and the extinction probability was 23% after 25 years, 95% after 50 years and 100% after 100 years. Removing mortality associated with collisions against fences lowered extinction probabilities to 0, 3 and 40% respectively, emphasizing fence removal as a management priority. Greatest declines occurred in Deeside and Donside, Morayshire and Ross‐shire and Perthshire and Trossachs. In the Badenoch and Strathspey stronghold, where an estimated 83% of males remain, numbers of occupied leks and lekking males have decreased in the last five years and are associated with reduced breeding success over the last 10 years. Our estimates of population size are only half that derived from the last official national survey in winter 2015/2016. We discuss possible reasons for this difference including underestimates from lek‐based surveys linked to male detection probabilities. Finally, we recommend improvements to the current annual monitoring scheme, including repeat counts at leks and use of novel remote acoustic devices and restoration of annual brood counts in remaining key forests.