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To determine whether ground‐disturbance increased Woodlark Lullula arborea abundance, we examined responses over 3 years to four treatments varying in establishment method (shallow‐ or deep‐cultivated) and complexity (homogeneous or 'complex‐mosaics' comprising fallow and recently cultivated subplots), plus controls, replicated across the largest lowland grass‐heath in the UK. Abundance increased through the study and was higher on plots closer to woodland and across all treatments. Within complex‐mosaics, Woodlark preferentially used recently cultivated subplots over 1‐ or 2‐year‐old fallows. Regardless of treatment detail, providing suitable foraging habitat within c. 45 m of woodland, through annual ground‐disturbance, can increase Woodlark abundance within lowland grass‐heaths characterized by closed swards. [ABSTRACT FROM AUTHOR]

Most altricial birds remove their nestlings’ feces from the nest, but the evolutionary forces driving this behavior are poorly understood. A possible adaptive explanation for this could be that birds avoid the attraction of nest predators to their nests due to the visual or olfactory cues produced by feces (nest predation hypothesis). This hypothesis has received contrasting support indicating that additional experimental studies are needed, particularly with respect to the visual component of fecal sacs. To test this hypothesis, we conducted an experiment manipulating the presence of fecal sacs on inactive Woodlark (Lullula arborea) nests. This ground nester has highly cryptic nests that are mainly depredated by visually oriented nest predators (i.e., corvids) in our study population, making it an excellent system to test for the nest predation hypothesis. Our results showed that the presence of fecal sacs in the nest does not seem to be an important factor explaining nest predation. Interestingly, the effect of nest concealment, the most important factor explaining nest predation in Woodlark nests, depended on whether the nest was depredated the previous year or not, supporting the importance of using different nesting sites between years. Our findings indicate that this important nest sanitation behavior is not likely motivated by nest predation and highlight the need to explore alternative selective pressures in this context. [ABSTRACT FROM AUTHOR]

After 30 years absence the Woodlark returned as a breeding species to the Canton of Geneva in the beginning of the 2000s. Searches carried out in 2016 in the commune of Dardagny and in 2017 throughout the Geneva wine growing areas found no less than 25 territories within the communes of Dardagny and Satigny with a high density of 4-6 singing birds per km². [ABSTRACT FROM AUTHOR]

The Woodlark is an insectivorous bird, which is listed as a priority species in Switzerland. In Valais, a stronghold of this species in the country, the birds breed in intensively managed vineyards and show a preference for parcels with ground vegetation during territory establishment. As a ground-breeder, the species is highly vulnerable to nest predation by avian and mammal predators. The aims of our study were firstly to investigate nest site preferences of the woodlark within vineyards and secondly to compare the predation risk of artificial nests dependent of ground vegetation structure. Our results point out that the Woodlark prefers patches of tall and dense ground cover within vegetated vineyard parcels and avoids parcels that have been treated with herbicides. In a follow-up experiment we conducted a study comparing the predation rate of artificial nests between bare parcels (<20% vegetated area) and vegetated parcels (>40% vegetated area). Artificial nests equipped with one quail egg were distributed pairwise between two adjacent parcels that fulfilled the upper criteria and were monitored by trail cameras during 10–12 days. Predation rate was generally low (4 predation events) and only occurred in bare parcels. These data indicate that conspicuousness of avian nests may be decreased in vegetated parcels and that the amount of vegetation can lower the predation risk on ground breeding birds - another indication for the importance of ground vegetation for a successful conservation of the endangered Woodlark in Swiss vineyards. [ABSTRACT FROM AUTHOR]

1. We examined the influence of local weather conditions on reproductive success, timing of breeding and survival in a population of a multi-brooded ground nesting passerine (woodlark Lullula arborea) over 35 years. 2. Woodlarks laid larger clutches when rainfall was low and temperature high during the egg-laying and pre-laying period. Nest success increased with higher temperatures during the nesting period. In successful nests, the number of chicks fledged per egg laid was greater when weather was drier during the brood stage. 3. Although woodlarks bred earlier in years with warmer early spring temperatures, with the onset of breeding varying by 25 days, there was no significant advance in the onset of breeding over the 35 years of study, due to considerable inter-annual variability, and no overall trend, in weather. 4. Simulation modelling of annual reproductive output demonstrated that earlier breeding could increase productivity by 23·5% in the warmest compared to the coldest year, due to birds having more nesting attempts. Other effects of weather on productivity affected breeding output to a lesser extent. 5. Effects of weather on productivity were minor compared to an increased rate of nest predation through the period of study, which reduced productivity by 49·8% by 2004 compared to 1971. 6. Turning points analysis identified three distinct demographic periods: from1971 to 1988 the population grew slowly, during 1988–1999 the population grew rapidly, but after 1999 the population declined. Increased population growth after 1988 was associated with higher first-year survival rates (estimated using a population model). Population decline after 1999 was caused by a combination of reduced productivity (resulting from increased nest failure rates attributed to predation) and lower first-year survival rates, that appear unrelated to winter temperature. 7. Climate change (long-term changes in weather) did not explain the marked changes observed in the population trajectory over 35 years. We suggest that understanding effects of both climate and habitat change on populations is essential in predictive population modelling. [ABSTRACT FROM AUTHOR]

Intra-seasonal changes of the ecological needs and the distribution patterns of multi-brooded bird species are a poorly studied but potentially important topic in avian conservation planning. In this study of a passerine species of conservation concern, the woodlark Lullula arborea, we highlight the conservation implications of spatial shifts of breeding territories and changes of habitat requirements during the course of the breeding season. We described the factors affecting the distribution and habitat selection of this species in the Trebbia river valley (northern Apennines, Italy), where we mapped woodlark territories during the average time of first and second clutches. A strong shift of territories towards higher altitudes with the progression of the season was observed. The habitat models predicting woodlark occurrence varied between the early and the late period. Specifically, fodder cover positively predicted occurrence early in the season, whereas late in the season occurrence was positively influenced by shrub cover, length of woodland edge, alfalfa cover and rocky areas. Accordingly, territories that were occupied throughout the entire season had greater fodder, shrub and rocky cover compared with those that were occupied only early in the season, suggesting that these variables were important in determining territory quality for woodlarks. Therefore, changing ecological needs of multi-brooded bird species during the breeding season have to be taken into account for defining appropriate conservation strategies. This was demonstrated by showing that the habitat variables predicting woodlark occurrence early in the season poorly predicted occurrence late in the season and vice versa. In conclusion, this study provides the first detailed assessment of habitat factors affecting the occurrence of breeding woodlarks in an important portion of the species' range, and represents the first explicit attempt to model seasonally changing ecological requirements of bird species for conservation purposes. Our findings suggest that complex data and flexible habitat management strategies are required to account for temporal changes in habitat suitability in multi-brooded bird species. [ABSTRACT FROM AUTHOR]

The Nightjar Caprimulgus europaeus and Woodlark Lullula arborea are identified as species of conservation concern at both a UK and a European level on account of historical declines in their population sizes and ranges. The UK populations of both species have increased significantly in recent decades and this paper reviews the extent, nature and causes of these population changes, based on evidence from national surveys and autecological studies. It also considers the future prospects of both species in the face of likely changes to their preferred habitats in Britain. Nightjar numbers have increased greatly since the national survey in 1981, when the British population was estimated at only 2100 churring males, with an estimated 3400 in 1992 and 4606 (± 913) in 2004. Population recovery has been closely associated with their colonization of clear-fell areas in planted forests. Over 57% of the calling (‘churring’) males recorded were in planted forests in 2004. Woodlark numbers have also made a substantial recovery from a low level of just 250 territories in 1986 to 1426–1552 territories in 1997. Over 85% of the Woodlark territories recorded in 1997 were on heathland or in planted forests. Despite these increases, both species continue to occupy only part of their much more extensive former breeding ranges. The recovery of these species has coincided with the availability of suitable open ground habitat resulting from the felling of forests planted in the late 1920s and 1930s, often on former heathland habitats, the clearance and restocking of areas damaged by storms in October 1987 and January 1990 and the restoration of heathland habitats. Forests and heathlands support the majority of the breeding populations of Nightjars and Woodlarks, although there are regional variations in their relative importance. The prospects for further recovery may be limited due to a reduction of open ground habitat following restocking of planted forests, including those damaged in the storms of 1987 and 1990, the effects of recreational disturbance and, at least locally, poor Woodlark breeding productivity due to predation. [ABSTRACT FROM AUTHOR]

Although density dependence has long been recognised as vital to population regulation, there have been relatively few studies demonstrating it spatially in wildlife populations, often due to the confounding effects of variation in habitat quality. We report on a study of woodlarks Lullula arborea, a species of European conservation concern, breeding on lowland heath in Dorset, England. We take the novel approach of utilising the birds’ response to human disturbance, which resulted in much of the variation in density but had no direct impact on demographic rates. Within years, in sites with greater density there were smaller mean chick masses, lower post-fledging survival, and higher rates of nestling mortality attributed to starvation. The effects on clutch size and fledging success were confounded by the area of grassland within a site. There was no effect on brood size. Density dependence also operated within sites between years: as density increased there were reductions in mean chick mass and post-fledging survival, while nestling mortality attributed to starvation increased. Density-dependent effects on clutch size were only weakly regulatory, whereas density-dependent starvation and post-fledging mortality rates contributed strongly to differences in overall breeding output. Heavier chicks (when 7 days old) were significantly more likely to fledge and less likely to starve. Broods with heavier chicks were more likely to supply recruits to the breeding population. Nestling mass was not a factor in survival in the immediate post-fledging period, suggesting that density-dependent processes act independently on this stage. We conclude that the number of birds per hectare of suitable habitat is a valid means of expressing density, and that habitat acts as a surrogate for food abundance through which density dependence operates on the woodlark population. [ABSTRACT FROM AUTHOR]

1. There is often a perceived conflict between recreational access and wildlife conservation. Although many studies have investigated the potential effects on birds, this is the first study to demonstrate an impact of recreational disturbance on population size. 2. We studied the impact of disturbance on a woodlark Lullula arborea population on 16 heathland sites in southern England. These sites all had historical records of breeding woodlarks and together encompassed a range of visitor-access levels. 3. A logistic regression model of patch use was used to quantify the area of habitat suitable for woodlarks. Woodlarks favoured patches with substantial proportions of bare ground and short vegetation. Across heaths, woodlark density (per hectare of suitable habitat) was lower on sites with higher levels of disturbance. Within heaths with recreational access, the probability of suitable habitat being colonized was lower in those areas with greater disturbance and was reduced to below 50% at around eight disturbance events per hour. There was no relationship between disturbance and daily nest survival rates. Birds on heaths with higher levels of disturbance fledged more chicks (per pair) because of a strong density-dependent increase in reproductive output. 4. A model is presented that predicts the consequences for the woodlark population of a range of access scenarios. The impact on the population depends on both the numbers of people and their spatial distribution. Under current access arrangements, a doubling of visitor numbers has little effect, while the same number of people distributed evenly across all sites leads to a major negative impact on the population. Density-dependent breeding success partially balances the negative effects of disturbance; however, we calculated that there is currently a 17% reduction in productivity compared with that predicted in the absence of disturbance. 5. Synthesis and applications. Many previous studies have stressed the negative effects of recreational disturbance on birds’ behaviour, distribution and breeding success. However, from a conservation viewpoint, the impact at the population level is of paramount importance. Modelling the population-scale consequences of alternative access scenarios will help policymakers develop appropriate mitigation measures. [ABSTRACT FROM AUTHOR]

Many lowland heathlands have been designated as Special Protection Areas under the European Union Birds Directive as they support populations of bird species of European importance listed in Annex I of the Directive, including Nightjar Caprimulgus europaeus, Woodlark Lullula arborea and Dartford Warbler Sylvia undata. Many lowland heaths are near to human settlements and are heavily used as open spaces by those living nearby. A number of past visitor surveys have established the range of uses to which urban heaths are subject, and the attitudes of those who use them. We have collated a number of these visitor surveys, many of which are unpublished reports relating to single sites, in order to provide a broad summary of access to heathlands. The majority of visitors to urban and suburban lowland heaths visit sites regularly and live nearby (within 5 km). A large proportion of visitors drive to sites and dog walking is the usual purpose for a visit. Visits are typically short, with the average dog walker travelling less than 2.5 km on the heath. Dog walkers typically stay on the paths, but most let their dog off the lead and consider it important to be able to do so. On large regionally or nationally known rural sites such as the New Forest, more visitors are day trippers and tourists, fewer are dog walkers, they stay for longer and their reasons for visiting differ from those of local residents. The information presented here is relevant in helping to inform decisions on the location of new housing development, and mitigating the impacts of existing and new settlements, as well as helping the heathland manager to make provision for visitors in ways that are most compatible with wildlife conservation. [ABSTRACT FROM AUTHOR]

We use a spatiotemporal Markov process to model the spread of an ecological population through its environment over time. Available habitat is divided into sites, and a parametric function of spatial variables is used to model the probability that one site is colonized from another. This allows us both to make predictions about the future spread of a population, and to determine which are the important factors governing colonizations. The model evolves in discrete time, allowing the population distribution to change seasonally in accordance with breeding patterns. Discrete time formulations are natural for ecological populations, but are problematic due to difficulties of fitting and predicting over irregular time intervals. The model described here can accommodate years of missing data and can therefore fit and predict at irregular intervals. Two methods of approximating the likelihood are described and applied to ornithological survey data for the woodlark, Lullula arborea from Thetford Forest in the U.K. [ABSTRACT FROM AUTHOR]

There is often a perceived conflict between allowing recreational access to the countryside and wildlife conservation. Although many studies have investigated potential impacts on birds, few have assessed the potential impacts of recreational disturbance at the population scale. We studied the impact of disturbance on a Woodlark Lullula arborea population on 16 heathland sites in southern England ( Mallord et al. 2006 ). These sites all had historical records of breeding Woodlarks, and together encompassed a range of visitor access levels. A logistic regression model of patch use was used to quantify habitat suitable for Woodlarks. Woodlarks favoured patches with substantial proportions of bare ground and short vegetation. Across sites, Woodlark density (per hectare of suitable habitat) was lower in sites with higher levels of disturbance. Within sites with recreational access, the probability of suitable habitat being colonized was lower in those areas with greater disturbance; this was reduced to below 50% at around eight disturbance events per hour. There was no effect of disturbance on daily nest survival rates. Birds on sites with higher levels of disturbance fledged more chicks (per pair) owing to a strong density-dependent increase in reproductive output. A model is presented ( Mallord et al. 2007 ) that predicts the consequences for the Woodlark population of a range of access scenarios. The model suggested that recreational disturbance is already having a major effect on the Woodlark population. Additionally, it predicted that any further impact on the population depended on both the numbers of people and their spatial distribution. Under current access arrangements, a doubling of visitor numbers had little effect, whereas the same number of people distributed evenly across all sites led to a major negative impact on the population. Many previous studies have stressed the negative effects of recreational disturbance on bird behaviour, distribution and breeding success. However, from a conservation viewpoint, the impact at the population level is of paramount importance. Modelling the consequences of alternative access scenarios will help policymakers in the development of appropriate mitigation measures. [ABSTRACT FROM AUTHOR]