Common Starling Sturnus Vulgaris Research Articles

Haemosporidian parasites (Apicomplexa, Haemosporida) of breeding common starling Sturnus vulgaris in Latvia

Migratory behaviour in seasonal environments affects host–pathogen relationships, especially for vector‐transmitted blood parasites of the order Haemosporida. The common starling Sturnus vulgaris is a short‐distance migrant where the north‐eastern European breeding population spend the non‐breeding season in temperate mild western Europe. Despite the high abundance and known susceptibility as a host, blood parasitism in wild starlings has rarely been studied with molecular methods. Here, we monitored haemosporidian parasitism in a Latvian starling population over four breeding seasons. We found a total annual parasite prevalence of 2.7–15.7% caused by four Haemoproteus, three Plasmodium, and one Leucocytozoon cytochrome‐b (cyt‐b) genetic lineages. Herein, seven of these lineages have been recorded for the first time in the common starling as host. Lineage‐specific parasitemia was generally low (Haemoproteus range: 0.008–1.028%, Plasmodium range: 0.002–0.005%, Leucocytozoon range: 0.003–0.004%) indicating chronic infection stages in all parasitised hosts during the breeding season. Additionally, the proportion of leukocytes in peripheral blood was enhanced in infected compared to non‐infected hosts indicating activated immune defence during the chronic infection stage. Finally, 11% (3 out of 27) of individuals had cleared the infection from peripheral blood after one year. Causes for the variability in infection prevalence in common starlings across years, as well as the transmission period during the host annual cycle, are still open for future studies.

Spring phenology is advancing at a faster rate than arrival times of Common Starling

Climate change poses significant impact on most migratory species, altering their breeding and non-breeding distributions, migration distances, and phenology. The ability of a population to track and adjust to the changing environmental conditions is a vital prerequisite for its persistence. In this study, we describe changes in spring arrival phenology of a short-distance migrant, the Common Starling Sturnus vulgaris, in Northeastern Europe and their relation to changes in the onset of meteorological spring during the last century. Phenological data were obtained from an open access database Chronicles of Nature Calendar that held 4291 usable records of the 1st spring observation date of Starlings from 171 phenological network sites between 1922 and 2017. Air temperature data were downloaded from the European Climate Assessment and Dataset database. We found that spring arrival time of Starlings was positively correlated with the onset of spring on a local and broad scale. Spring arrival progression followed a northeast gradient at an average rate of 1.6 days per one degree of latitude (ca. 71 km day−1) and 0.4 days per one degree of longitude (152 km day−1). During the 96-year long period, Starlings on average advanced their spring arrival time by 4.7 days at a rate of 0.05 days per year. However, changes in the onset of spring occurred more rapidly with an average rate of change of 0.18 days per year over the study period. These findings imply broad-scale adjustments in migratory patterns of a short-distance migrant that result from climate change-induced shifts in spring phenology. However, adaptations in bird migration phenology are not occurring fast enough to track and compensate for the rapid increase in air temperature, thus disrupting the earlier matching between bird arrival and spring onset.

Effectiveness of using nest boxes as a form of bird protection after building modernization

Modernization of urban buildings can decrease the availability of nesting sites in buildings, leading to sudden decreases in the density of avifauna. In this study, we investigated the use of nest boxes as a bird conservation measure after buildings were thermally modernized. In a 10 ha experimental area we mounted five types of nest boxes of different sizes and dimensions (a total of 132). Nest boxes were dedicated to species that lost access to their previous nesting sites. All species associated with the buildings significantly declined or disappeared. In the first year after the modernization, the House Sparrow (Passer domesticus) decreased by 66% compared with the period before the modernization, Eurasian Jackdaw (Corvus monedula) by 68%, Common Starling (Sturnus vulgaris) by 70%, and Common Swift (Apus apus) by 100%. In the first two years after the modernization, the birds nested only in nest boxes. Five years of monitoring showed that using nest boxes as compensation for bird nesting sites lost during the renovation of buildings can cause a population to recover to ca. 50% of its original level. To optimize deployments of nest boxes, wildlife managers should consider target species’ preferences for the dimensions and placement of boxes and limit the time boxes are used if a species prefers nesting outside nest-boxes, but in buildings (e. g. the House Sparrow) and does not require additional support.

Fauna and seasonal dynamics of birds number at the solid waste landfill and their possible impact on the activities of Kyzyl airport

In 20192020, as a part of the ecological and ornithological survey in Kyzyl airport and the aerodrome area, the birds of the municipal solid waste landfill located near the runway were studied in order to assess the impact of the landfill on the safety of aircraft flights. The observations carried out during the year revealed the species composition of the avifauna of the polygon, the background species of the polygon, and the annual population dynamics of each species. The black kite Milvus migrans Bodd., the mongolian gull Larus vegae mongolicus Sushk., the oriental carrion crow Corvus corone Eversm., and the common raven Corvus corax L. were classified as the most numerous aircraft-hazardous species of the landfill. daurian partridge Perdix dauurica Pall., Eurasian tree sparrow Passer montanus L. and house sparrow P. domesticus L., common starling Sturnus vulgaris L. and some other species of Passeriformes were also included in the background. Two periods of the maximum total number of birds at the landfill were identified: winter (January, February) and late summer (August). According to the conducted records of the number and characteristics of behavior the black kite is the greatest danger to flights; the most dangerous period is the end of August, when this species forms pre-flight clusters on the landfill. Such clusters can be up to 1500 birds in size. In the cold season, the most dangerous species are the common raven and the oriental carrion crow.

Sex and age differences in the diet of the Eurasian Sparrowhawk (Accipiter nisus) using web‐sourced photographs: exploring the feasibility of a new citizen science approach

Diet differences between the sexes and ages have often been recorded for bird species. Many raptor species show extreme sexual size dimorphism, with females often considerably larger than the males and these differences may be reflected in their diets. Diet studies in raptors most frequently focus on analysing prey remains or pellets collected at nest‐sites. These methods are subsequently limited to breeding birds in the breeding season and are also restricted by their inability to distinguish prey items between the sexes. The use of web‐sourced photographs to examine raptor diet has the potential to overcome some limitations of more traditional methods used to assess diet. We used this approach for the Eurasian Sparrowhawk Accipiter nisus in the United Kingdom, exploring diet between the sexes and ages throughout the entire year. In total, we obtained 843 web‐sourced photographs of Sparrowhawks with their prey items. There were 12 key prey items that had a frequency ≥ 10 in the Sparrowhawk diet: Common Wood Pigeon Columba palumbus, Common Starling Sturnus vulgaris, Eurasian Collared Dove Streptopelia decaocto, Rock Dove Columba livia, Common Blackbird Turdus merula, House Sparrow Passer domesticus, unidentified ‘small’ and ‘medium’ birds, European Goldfinch Carduelis carduelis, European Greenfinch Chloris chloris, Eurasian Blue Tit Cyanistes caeruleus and Stock Dove Columba oenas. Several prey species were more often seen in the diet of one sex or age group. Overall, average prey weights of adult females were two and a half times heavier than for adult males and one and a half times heavier for juvenile females. However, this method may be slightly biased towards larger prey items, which should be considered in future studies. Despite this limitation, our method enabled dietary differences between the sexes and ages of this highly sexual size dimorphic raptor species to be explored throughout the year.

Do nest boxes breed the target species or its competitors? A case study of a critically endangered bird

Nest boxes are widely used for habitat restoration. Unfortunately, competitors of the target species may exploit nest boxes, creating perverse outcomes. Avoiding habitats preferred by nontarget species, while favoring those of the target species, requires an adaptive management approach if limited information about species preferences is available when deploying boxes. Using nest boxes intended for Swift Parrots Lathamus discolor, we identify factors associated with nontarget species occupancy (Common Starling Sturnus vulgaris and Tree Martin Petrochelidon nigricans) in newly deployed boxes in 2016, and then again after 3 years had elapsed in 2019. Box occupancy by different species depended on the interaction between distance of individual boxes to the forest edge and year. Although the target species exploited similar numbers of nest boxes in both years, competitors were the main beneficiaries of established boxes. A subordinate native nest competitor increased box occupancy likelihood at greater distances from forest edges in both years, but the relationship was stronger in 2019. Introduced Common Starlings S. vulgaris were most likely to occupy boxes close to forest edges, but the magnitude of this relationship was much greater for established than newly deployed boxes. We suggest that permanent box deployments for Swift Parrots may produce perverse outcomes by increasing nesting habitat for Common Starlings. We suggest that for species that only use cavities for part of their life cycle, managers should limit access to boxes outside of critical times to reduce the likelihood that pest populations can exploit restoration efforts and create new problems.

The Shetland Bird Survey: population trends for widespread breeding birds 2002–2019

ABSTRACT Capsule Population trends are estimated for the first time for 12 species based on Shetland Breeding Bird Survey data collected between 2002 and 2019. Aim To provide population trends for a selection of commoner breeding waders and passerines on the Shetland Isles, the most northerly region of the UK, which has historically been under-represented in national bird monitoring schemes. Methods One hundred and forty-five self-selected 1-km2 squares were surveyed between 2002 and 2019 using similar methods to the BTO/JNCC/RSPB Breeding Bird Survey (BBS), the main breeding bird monitoring scheme in the UK. Results Over 17 years, Eurasian Oystercatcher Haematopus ostralegus, Northern Lapwing Vanellus vanellus, and Common Redshank Tringa totanus populations declined whilst Eurasian Curlew Numenius arquata and Common Snipe Gallinago gallinago showed no significant changes in their population trends. For passerines, Common Skylark Alauda arvensis and Northern Wheatear Oenanthe oenanthe populations declined, whilst Common Starling Sturnus vulgaris, Common Blackbird Turdus merula, and House Sparrow Passer domesticus increased. Winter Wren Troglodytes troglodytes and Meadow Pipit Anthus pratensis showed no significant population changes. Comparisons with BBS trends for the UK and for Scotland are provided. For Eurasian Curlew, Common Starling, and House Sparrow, trends were more favourable in Shetland than elsewhere in UK. Conclusion The Shetland Breeding Bird Survey provides useful trends for several bird species, which include important breeding numbers of Winter Wren and Common Starling (both endemic subspecies), as well as nationally important wader populations. We recommend increasing the number of survey squares sampled each year, which would increase the precision of population estimates. The inclusion of a random or stratified element to square selection would help to ensure that these trends are representative of the wider region.

Assessment of Avifaunal Diversity in Riverine and Urban Areas of Layyah along the River Indus, Punjab-Pakistan

Layyah City is located along the River Indus and provides rich habitat for a wide range of resident and migratory bird species. The present study documents for the first time the avifaunal diversity and abundance of urban and riverine sites of Layyah. Potential habitats around the city were identified and three study sites were selected, one in each of the main habitat types. A total of 223 species was recorded: 92 residents, 87 winter visitors, 42 passage migrants and two new records from the area. A Shannon Wiener Index of 4.36 indicates that the area has a high level of biodiversity. Of the species recorded, 16 are included in the IUCN Red list as vulnerable (N=6), near threatened (N=9) or endangered (N=1). The most abundant species were House Crow Corvus splendens, House Sparrow Passer domesticus, Common Myna Acridotheres tristis and Common Starling Sturnus vulgaris. Two species, Houbara or McQueen's Bustard Chlamydotis macqueenii and Black-headed Ibis Threskiornis melanocephalus were recorded for the first time from the area. Potential threats to the avian diversity of the area are hunting, habitat loss, and pollution.

Common Starling Sturnus vulgaris expansion in South Africa

The Common Starling Sturnus vulgaris has progressively expanded its range in South Africa since its introduction into Cape Town in the late 19th century. In the past few decades it has extended this range into Gauteng province. Using data from the Southern African Bird Atlas Project 2, this paper examines the spread and relative abundance changes for the species across South Africa over the past 10 years, with a detailed look at the recently-colonised Gauteng. Across South Africa, the Common Starling's distribution has shifted, and grown. As it spreads north along the coastline and northwards inland, some of the former range has been lost. In Gauteng, the species has shown a range and abundance expansion over the same period. If the observed trends are to continue, this species is likely to eventually become a prominent species across the entire country, and further north into the sub-region. However, the potential impact that this species has on indigenous avifauna is unknown and, in the face of rapid anthropogenic change, remains to be investigated.

Пространственная структура колонии и особенности гнездования обыкновенного скворца (Sturnus vulgaris) и полевого воробья (Passer montanus) в зеленой зоне г. Энгельса

Пространственная структура колонии и особенности гнездования обыкновенного скворца (Sturnus vulgaris) и полевого воробья (Passer montanus) в зеленой зоне г. Энгельса

Mortality and pathology in birds due to Plasmodium (Giovannolaia) homocircumflexum infection, with emphasis on the exoerythrocytic development of avian malaria parasites.

BackgroundSpecies of avian malaria parasites (Plasmodium) are widespread, but their virulence has been insufficiently investigated, particularly in wild birds. During avian malaria, several cycles of tissue merogony occur, and many Plasmodium spp. produce secondary exoerythrocytic meronts (phanerozoites), which are induced by merozoites developing in erythrocytic meronts. Phanerozoites markedly damage organs, but remain insufficiently investigated in the majority of described Plasmodium spp. Avian malaria parasite Plasmodium (Giovannolaia) homocircumflexum (lineage pCOLL4) is virulent and produces phanerozoites in domestic canaries Serinus canaria, but its pathogenicity in wild birds remains unknown. The aim of this study was to investigate the pathology caused by this infection in species of common European birds.MethodsOne individual of Eurasian siskin Carduelis spinus, common crossbill Loxia curvirostra and common starling Sturnus vulgaris were exposed to P. homocircumflexum infection by intramuscular sub-inoculation of infected blood. The birds were maintained in captivity and parasitaemia was monitored until their death due to malaria. Brain, heart, lungs, liver, spleen, kidney, and a piece of breast muscle were examined using histology and chromogenic in situ hybridization (ISH) methods.ResultsAll exposed birds developed malaria infection, survived the peak of parasitaemia, but suddenly died between 30 and 38 days post exposure when parasitaemia markedly decreased. Numerous phanerozoites were visible in histological sections of all organs and were particularly easily visualized after ISH processing. Blockage of brain capillaries with phanerozoites may have led to cerebral ischaemia, causing cerebral paralysis and is most likely the main reason of sudden death of all infected individuals. Inflammatory response was not visible around the brain, heart and muscle phanerozoites, and it was mild in parenchymal organs. The endothelial damage likely causes dysfunction and failure of parenchymal organs.ConclusionPlasmodium homocircumflexum caused death of experimental passerine birds due to marked damage of organs by phanerozoites. Patterns of phanerozoites development and pathology were similar in all exposed birds. Mortality was reported when parasitaemia decreased or even turned into chronic stage, indicating that the light parasitaemia is not always indication of improved health during avian malaria. Application of traditional histological and ISH methods in parallel simplifies investigation of exoerythrocytic development and is recommended in avian malaria research.

Soil pH and organic matter content add explanatory power to Northern LapwingVanellus vanellusdistribution models and suggest soil amendment as a conservation measure on upland farmland

Habitat associations of farmland birds are well studied, yet few have considered relationships between species distribution and soil properties. Charadriiform waders (shorebirds) depend upon penetrable soils, rich in invertebrate prey. Many species, such as the Northern Lapwing Vanellus vanellus, have undergone severe declines across Europe, despite being targeted by agri-environment measures. This study assessed whether there were additive effects of soil variables (depth, pH and organic matter content) in explaining Lapwing distribution, after controlling for known habitat relationships, at 89 farmland sites across Scotland. The addition of these soil variables and their association with elevation improved model fit by 55%, in comparison with models containing only previously established habitat relationships. Lapwing density was greatest at sites at higher elevation, but only those with less peaty and less acidic soil. Lapwing distribution is being constrained between intensively managed lowland farmland with favourable soil conditions and upland sites where lower management intensity favours Lapwings but edaphic conditions limit their distribution. Trials of soil amendments such as liming are needed on higher elevation grassland sites to test whether they could contribute to conservation management for breeding Lapwings and other species of conservation concern that depend upon soil-dwelling invertebrates in grassland soils, such as Eurasian Curlew Numenius arquata, Common Starling Sturnus vulgaris and Ring Ouzel Turdus torquatus. Results from such trials could support improvement and targeting of agri-environment schemes and other conservation measures in upland grassland systems.

I smell a rat: Can New Zealand birds recognize the odor of an invasive mammalian predator?

Abstract Although it is well known that birds can assess predation risk through visual and auditory cues, there has been little research into whether similar processes occur with olfactory cues. We examined the role of odor cues in assessing nest predation risk in four species of passerine birds in New Zealand. We compared the ability of two introduced European species (common starling Sturnus vulgaris and song thrush Turdus philomelos) and two native New Zealand species (rifleman Acanthisitta chloris and South Island robin Petroica australis) to respond to the scent of rat urine placed in the nest. Rats are an introduced predator in New Zealand and we expected the native birds, which did not co-evolve with any mammalian predators, to lack behavioral adaptations to the scent of rats at their nest. As expected, both riflemen and robins failed to show any change in their behavior at their nest when rat urine was present compared to a control period in which no scent was present. However, a similar lack of response was observed in the introduced song thrush; only the common starling changed its behavior in the presence of the rat urine. Starlings with rat urine at the nest box were more likely to hesitate before entering and they also approached the nest, but refused to enter more often in the presence of rat scent. Both responses suggest they detected the presence of a predator and changed their behavior to minimize risk to themselves. Although based on a small number of species, our results suggest that responses to predator scent may be less common in New Zealand species, and may be a factor contributing to the vulnerability of native birds to introduced mammalian predators.

Can artificial nest-cavities be used as a management tool to assist the control of Common Starlings (Sturnus vulgaris)?

Invasive species represent the second greatest threat to biodiversity after habitat loss, and significantly affect agriculture worldwide. The Common Starling (Sturnus vulgaris) is one of the world's worst invasive species and has established pest populations across the globe, with low-density, highly persecuted populations in Western Australia (WA) since the 1970s. This study examines the ongoing control of low-density populations of Common Starlings in WA. From May 2006 to June 2009 we monitored use by Common Starlings of 180 artificial nest-cavities of three designs, across three habitat types; the artificial cavities were standard wooden nest-boxes, and terracotta pipes orientated vertically or horizontally. During the trial, Common Starlings nested exclusively in wooden nest-boxes in swamps containing predominantly dead trees; they did not nest in the terracotta pipes. Wooden nest-boxes may have helped concentrate breeding Common Starlings in a defined area, thereby assisting control efforts.

Relationships among oxidative status, breeding conditions and life‐history traits in free‐living Great Tits Parus major and Common Starlings Sturnus vulgaris

The interest shown by ecologists in antioxidants and oxidative stress as potential modulators of life‐history trade‐offs has expanded greatly in recent years. However, we still know very little about natural variation in oxidative damage and antioxidant capacity in free‐living animals. In this study, we describe the natural variation in three components of oxidative balance in nestlings and breeding females in free‐living Great Tits Parus major and Common Starlings Sturnus vulgaris in central Italy, and relate these to breeding conditions and life‐history traits. Our results suggest that there are associations among oxidative physiology, reproductive activity, growth pattern and season in wild birds, but that the nature of these associations might be species‐specific rather than general across species.

Assessing the impact of Entry Level Stewardship on lowland farmland birds in England

Agri‐environment schemes (AES) are central to the conservation of Europe’s farmland biodiversity. The UK Government’s Public Service Agreement target seeks to reverse the decline of farmland birds in England by 2020 through the use of AES. The Entry Level Stewardship (ELS) scheme, introduced in 2005, is the first non‐competitive, broad‐uptake stewardship scheme designed to deliver simple but effective environmental management on farms throughout England. Approximately 5 million hectares of farmland are currently entered into Environmental Stewardship (ES) agreements, and given the scale of this investment it is important to verify the efficacy of ELS as a mechanism for delivering biodiversity benefits. We used spatially referenced ES agreement data to assess the influence of specific management options and combinations of options on farmland bird population changes between 2005 and 2008 derived from standardized surveys carried out on over 2000 lowland farmland 1‐km squares in England. The results showed only limited evidence for short‐term effects of ES. Only Corn Bunting Emberiza calandra and Common Starling Sturnus vulgaris showed some landscape‐specific positive associations with area under ELS management. There was also limited evidence for positive associations between specific management options and the population changes of the species at which they were aimed. The current pattern of option uptake may be limiting benefits of ELS, with boundary management accounting for over 50% of scheme compensation value. However, the time required for option maturation and the time lags in bird population responses to environmental change mean that it is too early to reach definitive conclusions about the success or failure of the scheme. The findings of this study will assist in the development of ELS by feeding into the 5‐year review scheduled for 2010 and have implications for the development of similar schemes elsewhere in Europe.

Habitat influences on urban avian assemblages

Urbanization is increasing across the globe and there is growing interest in urban ecology and a recognition that developed areas may be important for conservation. We review the factors influencing urban avian assemblages, focusing on habitat type and anthropogenic resource provision, and analyse data from a common bird monitoring scheme to assess some of these issues. The review suggests that (1) local factors are more important than regional ones in determining the species richness of urban avian assemblages, raising the potential for the management of urban sites to deliver conservation; (2) habitat fragmentation frequently influences urban avian assemblages, with the effects of patch size being greater than those of isolation, and (3) urban bird assemblages appear to respond positively to increasing the structural complexity, species richness of woody vegetation and supplementary feeding, and negatively to human disturbance. Data from Britain's Breeding Bird Survey, combined with habitat data obtained from aerial photographs, were used to assess a number of these issues at the resolution of 1‐km squares. Green‐space constituted 45% of these squares, and domestic gardens contributed 50% of this green‐space, though their contribution to large continuous patches of green‐space was negligible. There was no significant positive correlation between the densities of individual species in urban areas and surrounding rural areas. Rural species richness declined with increasing latitude, but urban species richness was not correlated with latitude. This contrast contributes to slightly higher avian species richness in rural squares in Southern England than urban ones. Occupancy and abundance were strongly positively correlated in urban avian assemblages, and some indicator species of conservation concern occurred in few urban areas and at low densities. Such species will require conservation action to be precisely targeted within urban areas. Of the urban indicators of conservation concern, only the House Sparrow Passer domesticus and Common Starling Sturnus vulgaris were more abundant in urban than rural areas. Moreover, the densities of these two species were strongly and positively correlated, indicating that they may be limited by shared resources, such as nest‐sites or supplementary food. There was little evidence that high densities of nest‐predating corvids were associated with reduced densities of their prey species. Species richness and the densities of individual species frequently declined with an increasing number of buildings. Current trends for the densification of many British urban areas are thus likely to be detrimental for many bird species.

Taxonomic recommendations for British birds: Fifth report

Taxonomic recommendations for British birds: Fifth report

The starvation–predation risk trade‐off, body mass and population status in the Common Starling Sturnus vulgaris

It is theoretically and empirically well established that body mass variation in small birds reflects a trade‐off between starvation risk and predation risk. This occurs because carrying increased fat reserves reduces starvation risk but also results in a higher predation risk due to reduced escape flight performance and/or the increased foraging exposure needed to maintain a higher body mass. In principle, therefore, the theory of mass‐dependent predation risk could be used to understand how a bird perceives and responds to the risks in its environment, because its mass will reflect the predictability of foraging opportunities and predation risk. Mass in birds may then provide a relatively straightforward way of assessing the foraging environment of birds and so the potential conservation problems a species faces. This study tests, for the first time for any species, how body mass changes in response to changing starvation risk, changing predation risk and changing population status. Common Starling Sturnus vulgaris mass varies as predicted by starvation–predation risk trade‐off theory: mass is lower when foraging conditions are more favourable and when predation risk is increased. The populations that are declining the most strongly have higher mass, which is most likely indicative of a poor foraging environment, leading to lower relative survival. The results suggest that increased mass in Starlings, and possibly in other species, may provide an indication of the poor quality of the foraging environment and/or rapidly declining populations.

Responses of birds to the characteristics of farm windbreaks in central New South Wales, Australia

In parts of Australia where the clearing of native vegetation has been widespread the establishment of windbreaks is a common farming practice. There is some evidence that birds respond to certain characteristics of windbreaks, particularly width. This is the first study to investigate such effects in Australia. Six properties, containing 61 windbreak sites, were surveyed for birds 12 times between 1993 and 1997. Generalised linear models were used to test relationships between 19 predictor variables and bird community attributes, including the densities of 14 species of birds. Canonical variate analysis was undertaken to discriminate among four types of windbreaks and their avifauna. Species known to be declining in the region and uncommon (<100 observations) woodland birds were more abundant in wider and more floristically diverse windbreak sites. Several native species had a positive response to tree-height, density of under-storey, structural diversity, the proportion of native plant species in the site or the proximity of remnant bushland. The density of introduced bird species, as a group, was strongly negatively related to the proportion of native plants and, for one species, Common Starling (Sturnus vulgaris), to width of windbreak. Recommendations for windbreak design are provided and include: using a diversity of native plants; providing adequate width, preferably over 20 m; and having a diversity of understorey densities. It is also recommended that patterns of experimental windbreaks are created that could be used for formal hypothesis testing.