Bird Survey Research Articles

From small waterbodies to large multi-service providers: Assessing their ecological multifunctionality for terrestrial birds in Mediterranean agroecosystems

Agricultural intensification has caused a rapid loss of singular landscape elements worldwide, such as farmland ponds, hedgerows and field margins, leading to a steep decline in farmland bird populations. Farmland ponds and traditional small waterbodies (SWB) have been recently reported to support species-rich bird communities at landscape scale in several agroecosystems. However, a comprehensive assessment on the potential ecological functions provided by SWB to terrestrial birds has been never conducted. Here, we used data from breeding bird surveys at 39 traditional SWB to highlight the variety and magnitude of ecological functions provided to terrestrial birds. These SWB belonged to three different structural types and were spread along an environmental gradient in Mediterranean agroecosystems from southeastern Spain. We identified up to six cross-system services benefiting different functional guilds of terrestrial birds. Apart from to the well-documented supply of drinking water, traditional SWB delivered other ecologically relevant and commonly overlooked services to terrestrial birds, such as the provision of bathing sites, essential food resources (e.g., emerging insects), nest-building material and suitable adjacent perches for territorial display or thermoregulation. Structural and environmental variables at waterbody scale played an important role as determinants of the recorded ecological functions. Importantly, most of these ecological functions were evenly observed across the three types of traditional SWB, thus supporting the key role of these singular landscape elements for bird conservation regardless their structural attributes. Agri-environment schemes and farmland biodiversity conservation strategies should account for the ecological multifunctionality of traditional SWB by ensuring the protection and nature-friendly management of these valuable habitats, as well as by promoting the diversity of microhabitats at SWB scale.

A checklist of avifauna from different microhabitats in Muttukadu backwaters, Tamilnadu, India

Muttukadu backwaters cover an area of 215.36 acres and lies between 12.8006°N latitude and 80.2363°E longitude. It is situated in Chengalpet district of Tamilnadu, India. This backwater forms a network of microhabitats for different kind of birds. The exchange of seawater and freshwater in this region regulates salinity and nutrient levels, increasing the diversity of baseline producers and consumers in the ecosystem, which attracts and sustains waterbirds. Bird survey was conducted during July 2021–March 2023 using block count and total count method. Identification was done up to species level by using standard field guides. The objective of this study is to prepare a checklist of avian species in different microhabitats based on their habitat preference, feeding habits, migratory, and conservation status. During the present study, a total of 124 species belonging to 19 orders and 45 families were recorded. Among them, seven near-threatened species were recorded. The presence of significant number of migrants and threatened species indicates the importance, both ecologically and biologically of the study area for resident and migratory birds. The current checklist represents the first attempt to compile a comprehensive list of the birds found in the Muttukadu backwaters.

Challenging the geographic bias in recognising large‐scale patterns of diversity change

AbstractAimGeographic structure is a fundamental organising principle in ecological and Earth sciences, and our planet is conceptually divided into distinct geographic clusters (e.g. ecoregions and biomes) demarcating unique diversity patterns. Given recent advances in technology and data availability, however, we ask whether geographically clustering diversity time‐series should be the default framework to identify meaningful patterns of diversity change.LocationNorth America.TaxonAves.MethodsWe first propose a framework that recognises patterns of diversity change based on similarities in the behaviour of diversity time‐series, independent of their specific or relative spatial locations. Specifically, we applied an artificial neural network approach, the self‐organising map (SOM), to group time‐series of over 0.9 million observations from the North American Breeding Birds Survey (BBS) data from 1973 to 2016. We then test whether time‐series identified as having similar behaviour are geographically structured.ResultsWe find little evidence of strong geographic structure in patterns of diversity change for North American breeding birds. The majority of the recognised diversity time‐series patterns tend to be indistinguishable from being independently distributed in space.Main ConclusionsOur results suggest that geographic proximity may not correspond to shared temporal trends in diversity; assuming that geographic clustering is the basis for analysis may bias diversity trend estimation. We suggest that approaches that consider variability independently of geographic structure can serve as a useful addition to existing organising rules of biodiversity time‐series.

The status of the UK breeding European Turtle Dove Streptopelia turtur population in 2021

ABSTRACT Capsule The first UK European Turtle Dove Streptopelia turtur survey, in 2021, estimated the breeding population at 2092 territories. Aims Changes in European Turtle Dove abundance in the UK have been monitored through schemes like the BTO/JNCC/RSPB Breeding Bird Survey, however, sample size is now too low to calculate robust trends going forward. The aims of this volunteer-based survey were to provide a new UK population estimate and create a baseline to monitor future population trends. Methods A stratified random sample of one-kilometre squares were surveyed within the core counties for the species. Elsewhere, one-kilometre squares containing recent European Turtle Dove records were targeted. The survey used a two-visit territory mapping approach, with observers asked to get within 200 metres of potentially suitable nesting or foraging habitat. Visits were undertaken in the early morning, to coincide with peak vocal activity, from 11 May to 31 July. Results The UK population estimate in 2021 was 2092 territories (95% confidence limits, 1559–2782). The species has become increasingly restricted to eastern and southeastern England, with 62.5% of the population estimated to occur in three counties: Kent (682 territories; 32.6%), Suffolk (326; 15.6%) and Essex (300; 14.3%). Additional hotspots occurred in other counties in eastern England, up to North Yorkshire. Conclusion This result suggests a 98% decline in abundance since the 1968–1972 breeding atlas, similar to trends identified from UK bird monitoring schemes, and a substantial contraction in range since the 2007–2011 bird atlas. The temporary cessation of hunting along their European western flyway provides a vital window of opportunity to scale up the delivery of high-quality breeding habitat and increase food availability in the UK. The survey should be repeated in 2026, and regularly thereafter, to help monitor the effectiveness of conservation interventions.

Bird Object Detection: Dataset Construction, Model Performance Evaluation, and Model Lightweighting.

The application of object detection technology has a positive auxiliary role in advancing the intelligence of bird recognition and enhancing the convenience of bird field surveys. However, challenges arise due to the absence of dedicated bird datasets and evaluation benchmarks. To address this, we have not only constructed the largest known bird object detection dataset, but also compared the performances of eight mainstream detection models on bird object detection tasks and proposed feasible approaches for model lightweighting in bird object detection. Our constructed bird detection dataset of GBDD1433-2023, includes 1433 globally common bird species and 148,000 manually annotated bird images. Based on this dataset, two-stage detection models like Faster R-CNN and Cascade R-CNN demonstrated superior performances, achieving a Mean Average Precision (mAP) of 73.7% compared to one-stage models. In addition, compared to one-stage object detection models, two-stage object detection models have a stronger robustness to variations in foreground image scaling and background interference in bird images. On bird counting tasks, the accuracy ranged between 60.8% to 77.2% for up to five birds in an image, but this decreased sharply beyond that count, suggesting limitations of object detection models in multi-bird counting tasks. Finally, we proposed an adaptive localization distillation method for one-stage lightweight object detection models that are suitable for offline deployment, which improved the performance of the relevant models. Overall, our work furnishes an enriched dataset and practice guidelines for selecting suitable bird detection models.

TEMPERATURE AND WIND SPEED DRIVE BIRD SPECIES RICHNESS IN BRAZILIAN ARID HIGHLAND SCRUB

Due to timely and financial hampering in developing nations, field research has been encouraged to use rapid and cost-effective methods without compromising the acquisition of good-quality data. Species richness is a widely used component in ecological studies, especially of birds, which are conspicuous, diurnal, and excellent bioindicators. Birds are also a proper taxonomic group for leading conservation planning. Therefore, conducting efficient bird censuses is of paramount importance worldwide. The aim of this research was to determine abiotic environmental factors that drive the record of species richness and further suggest climatic conditions to improve bird survey efficiency. Species lists were used to census bird communities in four localities in central Bahia, northeastern Brazil, within the Caatinga, an exclusive Brazilian biome. During the beginning of mornings, temperature and atmospheric pressure increased hourly, but wind speed showed no temporal pattern. Species richness was higher when temperatures and atmospheric pressure were lower, but there was no evident tendency between the number of species and wind speed. However, the additive interaction of temperature and wind speed accounted for the most plausible competing model. This suggests that in this Brazilian arid non-forested open-canopy and wind-susceptible habitats, censusing birds will record more species when temperatures are low (~20º C), but wind blows below speeds of ~10 m/s.

Why do we do what we do?

In the fifty years since I became a scientist, there have been many changes in the way we work, in the tools we use, in the software we have available to us and much more. But our motivation to “Do what we do” hasn’t really changed at all. A survey carried out many years ago in Brazil asked biologists why they became biologists. Answers included going to the beach with the family and making shell collections and then trying to identify them; being involved in backyard bird surveys; catching butterflies in the local meadows, etc. In my own case, it was working on the farm with my father who, at least to me at the time, knew every native plant in the area as well as the grasses and crop plants. I began collecting and pressing grasses at a young age, and those collections are now housed in the herbaria of the University of New England and James Cook University of North Queensland. I am sure that most of you here have similar stories. In this presentation, I talk about the changes that I have seen over those fifty years in the way we work, including working at the Australian Biodiversity Resources Study (ABRS) on the Australian Plant Name Index (APNI) and the Flora of Australia; the Environmental Resources Information Network (ERIN) on digitisation projects; environmental, species and climate change modelling; data quality and decision support systems; with the Centro de Referência em Informação Ambiental (CRIA) on data quality and niche modelling; and on projects for the Global Biodiversity Information Facility (GBIF), The Global Environment Facility of the World Bank, United Nations Environment Programme (UNEP), Bioversity International, and others on a range of topics including on the conservation of crop wild relatives, reserve selection, rapid biodiversity assessment, data quality, and georeferencing—and, of course, Biodiversity Information Standards (TDWG). I’ll also touch on working with citizen science and tools such as iNaturalist. One key change in the way we work now compared to those early years is in the way we collaborate. A lot of that collaboration has been enhanced and made possible by the Internet: email, the World Wide Web, video conferencing, and chat tools like Zoom. Previously we published some research and then later another person would see that research and add to it, etc. This could take years for advancements to take place. Now, we collaborate: across institutions, countries and across the globe and that has sped up the rate our science can advance. TDWG has been a great example of that collaboration, along with agencies such as GBIF. So where will our science take us over the next fifty years? I have no idea, but the advances are likely to be at least as great as the last fifty, so I envy the young scientists in the audience just starting out and getting to grips with artificial intelligence (AI) and all that is likely to bring. We should be wary of AI—but not scared of it—just like computing fifty years ago. In conclusion, what then motivates us to continue to “Do what we do” well past retirement age? In my own case, my motivation throughout my life, has been to add to the biodiversity knowledge base so that those who come after me start at a far better knowledge level than would otherwise have been the case.

Bird surveys at windfarms in the Eastern Cape, South Africa

Bird surveys were conducted at four windfarm sites and four control sites in the Eastern Cape, South Africa. Numbers of the Blue Crane Grus paradisea decreased at three out of four windfarm sites after commencement of windfarm activities and did not decrease at any of the control sites. Numbers for several bird species of the fynbos and grassland tended to increase at windfarm sites after commencement of windfarm activities, and did not increase at the control sites.

Cavity‐nesting birds are limited by nesting habitat in Neotropical agricultural landscapes

AbstractMost studies comparing biodiversity between natural and human‐modified landscapes focus on patterns in species occurrence or abundance, but do not consider how different habitat types meet species' breeding requirements. Organisms that use or nest in tree cavities may be especially threatened by habitat conversion due to the loss of their nesting sites. Although cavity‐nesting bird diversity is highest in the tropics, little is known about how tropical birds use cavities, how agriculture affects their reproductive biology, and how effective nest boxes could be as a conservation strategy in tropical agriculture. Here, we explored how habitat conversion from tropical forests to pasture affects the abundance, nesting habitat availability, and nest success of cavity‐nesting birds in Northwest Ecuador. We conducted bird surveys and measured natural cavity availability and use in forest and agriculture. We also added artificial nest boxes to forest and agriculture to see whether cavity limitation in agriculture would elicit higher use of artificial nest boxes. We found evidence of cavity limitation in agriculture—there were many more natural cavities in forest than in agriculture, as well as more avian use of nest boxes placed in agriculture as compared to forest. Our results suggest that it is important to retain remnant trees in tropical agriculture to provide critical nesting habitat for birds. In addition, adding nest boxes to tropical agricultural systems could be a good conservation strategy for certain species, including insectivores that could provide pest‐control services to farmers.Abstract in Spanish is available with online material.

Characterizing bird species for achieving the win-wins of conserving biodiversity and enhancing regulating ecosystem services in urban green spaces

Urban green spaces provide regulating ecosystem services (RS) to humans and contribute to biodiversity conservation under urbanization pressure. However, trade-offs arise while making development decisions in urban green space planning, as the prioritization of enhancing RS may not always contribute to biodiversity conservation and vice versa. Therefore, achieving a balance between these trade-offs becomes essential in promoting conservation strategies that maximize win-win outcomes for both biodiversity and RS, ultimately leading to sustainable urban development. A practical approach to strike this balance is to prioritize specific species as surrogates for population protection, thereby benefiting co-occurring species and promoting the maintenance of a high RS level. To explore this approach, we conducted monthly bird surveys in green spaces over five years along an urbanization gradient in Shanghai, China. Based on the monthly bird dataset, to begin, we used indicator species analysis to identify bird indicators for the monthly RS (which were calculated from an economic perspective). Following from that, the umbrella index was used to prioritize umbrella species for biodiversity conservation. Finally, surrogate species were selected on the basis of their identification as both RS indicators and umbrella species. Consequently, seven common species were identified as surrogates in Shanghai. The RS indicator species were mainly omnivores and tree-nesting, with most umbrella species belonging to this subset. Furthermore, understanding the population dynamics of surrogate species could provide information on overall biodiversity and RS status, facilitating the optimization of management strategies and policies in cities. Our integrated approach, which combines indicator and umbrella species, provides a tool for establishing connections between ecosystem service maintenance and biodiversity conservation. This approach is useful in promoting planning strategies to conserve biodiversity while ensuring sustainable provision of ecosystem services and can be applied in the sustainable management of human-dominated landscapes.

Temperature niche composition change inside and outside protected areas under climate warming.

Conservation of biodiversity relies heavily on protected areas but their role and effectiveness under a warming climate is still debated. We estimated the climate-driven changes in the temperature niche compositions of bird communities inside and outside protected areas in southern Canada. We hypothesized that communities inside protected areas include a higher proportion of cold-dwelling species than communities outside protected areas. We also hypothesized that communities shift to warm-dwelling species more slowly inside protected areas than outside. To study community changes, we used large-scale and long-term (1997-2019) data from the Breeding Bird Survey of Canada. To describe the temperature niche compositions of bird communities, we calculated the community temperature index (CTI) annually for each community inside and outside protected areas. Generally, warm-dwelling species dominated communities with high CTI values. We modeled temporal changes in CTI as a function of protection status with linear mixed-effect models. We also determined which species contributed most to the temporal changes in CTI with a jackknife approach. As anticipated, CTI was lower inside protected areas than outside. However, contrary to our expectation, CTI increased faster over time inside than outside protected areas and warm-dwelling species contributed most to CTI change inside protected areas. These results highlight the ubiquitous impacts of climate warming. Currently, protected areas can aid cold-dwelling species by providing habitat, but as the climate warms, the communities' temperature compositions inside protected areas quickly begin to resemble those outside protected areas, suggesting that protected areas delay the impacts of climate warming on cold-dwelling species.

Biodiversity survey in medicinal and aromatic plant fields

Medicinal and aromatic plants (MAPs) in mountain regions are cultivated on small-scale farms, which are characterized by a great diversity of MAPs grown on a relatively small area and by a high degree of habitat complexity. Non-crop elements (e.g., dry-stone walls, hedges, etc.) are widely present in the cultivated areas and, together with the high plant diversity, may provide ideal foraging and breeding habitats for several animal groups. Here we surveyed small-scale MAP fields from a multi-taxonomic perspective considering flower-visiting arthropods, butterflies, grasshoppers, ground-dwelling arthropods, birds, and bats. A total of three MAP fields were surveyed, however not every taxon was surveyed in each MAP field. Pan traps were used in all MAP fields to assess flower-visiting arthropods with special attention to wild bees. In one of the selected fields a Malaise trap was used, and the other taxa were surveyed according to the protocol of the Biodiversity Monitoring South Tyrol. An exception was the bird surveys, which were conducted in two MAP fields. Our results indicate MAP fields to be a valuable habitat for several taxa, especially wild bees, as reflected in the positive correlation of wild bee species richness and flower coverage. Next to beneficial arthropods, potential pests, such as aphids were also highly abundant. However, natural enemies (e.g., hymenopteran parasitoids, ground-dwelling predators, etc.) possibly counteracting pests were also numerous. The butterfly and grasshopper fauna were represented by common and generalist species, while the observed vertebrate communities were relatively diverse in their habitat requirements, most likely using MAP fields for foraging. Overall, we conclude that MAP cultivation may act as resource-rich oases for several animal groups, thereby promoting biodiversity also on a broader scale.

Birds of SABAP2 pentad 2915_2555 on the Jagersfontein Road, south-west of Bloemfontein, Free State

This paper describes results of a bird survey done at Pentad 2915_2555 on the Jagersfontein road south-west of Bloemfontein between April 2008 and January 2023. A total of 197 species have been recorded from mainly 169 full-protocol SABAP2 cards (162 done by author) and more than 30 ad hoc lists. The seasonality of waterbird species is discussed based on responses and occurrences after the rainfall seasons. Higher reporting rates were obtained for species such as Yellow-billed Ducks (49.7%), Red-billed Teals (37.9%) and White-faced Whistling Ducks (32.0%) during the summer months, which were sometimes still present into the drier winter months. Spur-winged Goose (39.6%) and Egyptian Goose (69.2%) also have high reporting occurrences, although South African Shelducks showed a more seasonal occurrence with lower reporting rates (17.8%). The seasonality of winter visiting species such as Swallow-tailed Bee eater and Sickle-winged Chats is discussed. Sickle-winged Chats were mostly observed in the area between April–August preferring low shrubs in open patches in grassland and on gravel roads. Swallow-tailed Bee eater were observed in the Buddleja sp. bush areas on the slope of the hill at the Praalhoek farm between May and July. The seasonal occurrence of Melodeuis Larks, which starts singing after the first summer rains, is also discussed. The ongoing monitoring of bird populations through the SABAP2 project (and with other platforms such as the Virtual Museum digitization projects) is emphasized and therefore the importance of monitoring bird populations over time.

Documentation of Avian Species Composition and Assemblage in Agricultural Landscapes of Sirsa, Haryana

Avian communities maintain ecological balance by eliminating pests, providing ecosystem services, and acting as biological indicators, thereby playing a pivotal role in conserving agricultural landscapes’ integrity and stability; thus from an environmental monitoring standpoint, assessment of bird aggregations in various landscapes is necessary. A two-year bird survey was conducted from May 2020 and 2021 to October 2020 to 2021 to document the checklist, density, and diversity of bird species assemblage of agricultural landscapes in the Sirsa district of Haryana, India, to obtain the richness of birds in two different agricultural habitats. A total of 87 bird species from 39 families and 16 orders were recorded; four bird species (Alexandrine Parakeet, Asian Woollyneck, Black-Headed Ibis, and Painted Stork) are listed as Near Threatened in the ‘IUCN’ (2010) category. Surprisingly, 13 species with global declining population trends are rare in the study area. The Passeriformes order, with 44 species, is the most diverse in the study area. In all habitats, analysis of food and feeding guilds, as well as perching activity, revealed that the insectivorous guild (32) is dominant, followed by Omnivore (29), Carnivore (13), Granivore (7), Frugivore (5), and Nectarivore (2). The findings from this study suggest that biodiversity-friendly agricultural practices should be implemented to improve bird habitat quality in agricultural landscapes.

SiulMalaya: an annotated bird audio dataset of Malaysia lowland forest birds for passive acoustic monitoring

The laborious point count method of conducting bird surveys is still a common practice in Malaysia. An alternative method known as passive acoustic monitoring (PAM) is deployed in many countries by placing sound recorders at surveying sites to collect bird sounds. Studies revealed that the number of bird densities counted by human observers was agreeable with those obtained using PAM. However, one of the most essential gaps in conducting PAM is the lack of expert-verified bird-call databases. Therefore, the aim of this study is to construct the first annotated Malaysia lowland forest bird sounds called SiulMalaya to be used as ground-truth datasets for PAM-related activities. The raw bird sounds dataset was downloaded from Macaulay Library using the eBird platform. Data pre-processing was done to produce annotated audio tracks that can be used as training datasets for bird classification. SiulMalaya dataset was further validated by two bird experts from the Department of Wildlife and National Parks, Malaysia. A bird identification experiment was carried out to assess and validate SiulMalaya dataset using a convolutional neural network (CNN) learning model. Even though the accuracy of bird identification is slightly above 50%, the annotated dataset is shown to be viable for PAM-related operations.

Family group structure of the endangered Yellow Cardinal (Gubernatrix cristata)

The monogamous mating system, where a male and a female constitute the reproductive unit and share the parental care, predominates among bird reproductive strategies. However, there are also other mating systems with diverse parental care roles which may have implications for population breeding success and be relevant for their management and conservation. We evaluated the family group structure of the Yellow Cardinal ( Gubernatrix cristata) in La Pampa province of central Argentina. During the 2020–2021 breeding season we carried out 280 bird surveys to search for the presence of Yellow Cardinals. We registered 87 individuals (11 solitary individuals, 12 pairs, two males together, and 13 family groups). Most family groups corresponded to the typical monogamous structure, but two family groups (8%) were composed of two adult males, an adult female and at least a juvenile. We also explored 1646 Yellow Cardinal records at citizen science platforms and none of them included a family group with more than two adults. Even so, it would be feasible to release seized groups of two males together, to promote breeding success. Further studies are necessary to evaluate the causes of the presence of extra males and their incidence on the breeding performance of this globally endangered species. This may help to understand its natural history and for planning management and conservation actions.

SiulMalaya: an annotated bird audio dataset of Malaysia lowland forest birds for passive acoustic monitoring

The laborious point count method of conducting bird surveys is still a common practice in Malaysia. An alternative method known as passive acoustic monitoring (PAM) is deployed in many countries by placing sound recorders at surveying sites to collect bird sounds. Studies revealed that the number of bird densities counted by human observers was agreeable with those obtained using PAM. However, one of the most essential gaps in conducting PAM is the lack of expert-verified bird-call databases. Therefore, the aim of this study is to construct the first annotated Malaysia lowland forest bird sounds called SiulMalaya to be used as ground-truth datasets for PAM-related activities. The raw bird sounds dataset was downloaded from Macaulay Library using the eBird platform. Data pre-processing was done to produce annotated audio tracks that can be used as training datasets for bird classification. SiulMalaya dataset was further validated by two bird experts from the Department of Wildlife and National Parks, Malaysia. A bird identification experiment was carried out to assess and validate SiulMalaya dataset using a convolutional neural network (CNN) learning model. Even though the accuracy of bird identification is slightly above 50%, the annotated dataset is shown to be viable for PAM-related operations.

Investigating the effects of tree species diversity and relative density on bird species richness with acoustic indices

Mixed-species forest stands may provide suitable habitats for more bird species than tree monocultures by increasing the number of niches and resources available. However, assessing the effects of forest diversity on birds over time and across multiple sites using traditional bird survey methods can be expensive, time-consuming and impractical. Alternatively, we used passive acoustic monitoring (PAM) and acoustic indices to investigate how tree species diversity, relative density, and other plot characteristics affect the species richness of avian communities in temperate forests. Acoustic monitoring was conducted in Nationalpark Hainich, Germany, using plots which differed in tree species diversity and relative species density. Using a subset of our data, five acoustic indices, the normalised difference soundscape index (NDSI), acoustic complexity index (ACI), bioacoustic index (BI), the acoustic evenness index (AEI) and temporal entropy (Ht), were initially assessed using audio recordings of different soundscape elements to determine the degree to which they were influenced by non-biophony soundscape elements. Of these, NDSI, ACI and BI were considered least biased and displayed significant positive relationships with bird species richness assessed using audio recordings. However, NDSI values plateaued at around 5 bird species when measuring bird species richness and ACI values for dawn choruses were lower than expected, potentially due to the high density of birdsong saturating the soundscape. Plot tree species diversity had significant positive effects on ACI and BI during dawn, dusk and daytime periods. Increased basal area of sycamore (Acer pseudoplatanus) and, to a lesser degree, beech (Fagus sylvatica), had a negative effect on acoustic indices. These results could potentially be due to the earlier leaf out timings of these tree species in relation to the dates when surveys were performed. While the use of PAM and acoustic indices enabled surveys across multiple sites over longer time periods than would previously have been achievable, our results show that care should be taken when selecting indices and interpreting acoustic index results.

Trending against the grain: Bird population responses to expanding energy portfolios in the US Northern Great Plains.

Future global energy demand may be met through increased extraction of fossil fuels and production of renewable energy such as biofuels. Renewable energy from biofuels is often proposed as an environmentally friendly alternative to fossil fuels; however, impacts of renewable energy sources on wildlife populations have rarely been evaluated in working landscapes. We used North American Breeding Bird Survey data (1998 to 2021) to assess whether the joint effects of oil and gas and biofuel crop production explained grassland bird population declines. We modeled location-specific effects of land use on grassland bird habitat use for four grassland bird species (bobolink [Dolichonyx oryzivorus], grasshopper sparrow [Ammodramus savannarum], Savannah sparrow [Passerculus sandwichensis], and western meadowlark [Sturnella neglecta]) in North Dakota, a state experiencing rapid growth in both energy sectors. Our analysis showed that grassland birds responded more negatively to biofuel feedstocks (i.e., corn and soybeans) on the landscape compared with oil and gas development. Furthermore, we found that the effect of feedstocks was not generalizable to other forms of agricultural land use. When combined, these land use changes resulted in distributional shifts of grassland birds, with use by birds being lower in regions dominated by biofuel production, which appears partially responsible for observed abundance trends at the state level. Our results indicate that expansion of oil and gas development has negatively affected habitat use by some grassland birds, but this impact was more localized when compared to biofuel crops. Conservation practitioners may need to adapt their conservation strategies to account for widespread and rapid land use change driven by United States energy policies.

The observation of birds from a citizen science leisure project to systematic research

This article analyses historical data from observations made of birds in breeding season, throughout two routes with urban characteristics. The data were collected during a consecutive period of 10 years (2009-2018), following a precise methodology designed by the North American Breeding Bird Survey. The analyzed routes are officially registered in the Mexican Commission for Biodiversity’s Knowledge and Use, the United States Geological Survey Patuxent Wildlife Research Center, and the Canadian Wildlife Service Research Centre. The observations were made by citizens without formal professional education; hence the results may be considered within the framework of citizen science. Their contributions provided important data for decision-making regarding environmental issues, since the presence of birds is considered one of the main indicators of the health conditions of an ecosystem. Data analysis identified two basic conditions: (i) a reduction of the 23% in the number of species found, many of which disappeared during counting; and (ii) the significant increase in population of other species, including three species of pigeons. Apart from the study of variations in the numbers of bird species present in the routes with urban characteristics, the article acknowledges the lack of connection and use of this citizen science for decision-making and education regarding environmental issues. Therefore, we consider it crucial to create scientific observations that are available to both experts in the field and to the general population, which is the essence of citizen science.