Owl Nests Research Articles

Multi-scale analysis of barn owl nest box selection on Napa Valley vineyards

Abstract Barn owls ( Tyto alba ) have the potential to remove significant numbers of rodent pests in vineyards, which has prompted viticulturists in California to erect artificial nest boxes to attract owls. This study examined the habitat factors influencing barn owl nest box occupancy as well as farmers’ perceptions of barn owls in vineyards in Napa Valley, CA. Nest boxes of variable design and placement were distributed across 65 vineyards that varied in local and landscape habitat composition. We monitored 297 nest boxes in 2015 to develop an occupancy model. We evaluated the performance of the 2015 model by revisiting 150 boxes in 2016 and comparing observed occupancy to the predicted probability of occupancy for each nest box. Barn owls occupied approximately one third of the nest boxes we monitored each year. We used variance decomposition to address cross scale correlations among three nested spatial scales and to analyze the variation in nest box occupancy explained uniquely by predictors at each spatial scale. The home range and nest box scales were the most important spatial scales. At the home range scale, barn owls selected nest boxes surrounded by more hectares of grassland, riparian and mixed forest, and fewer hectares of oak scrub within 1 km of the box. Owls were more likely to occupy nest boxes if they were constructed of wood, facing north and positioned higher off the ground. The model developed in 2015 performed well in 2016, correctly classifying 81.3% of the boxes, and the area under the receiver operating characteristic curve was 0.86. In addition, we surveyed farmers to gauge their perceptions of the utility of barn owls as a component of an integrated pest management scheme in winegrape vineyards. The majority of farmers surveyed installed barn owl nest boxes for the perceived pest management services instead of the potential positive public appeal of improving barn owl habitat.

Competitors and predators alter settlement patterns and reproductive success of an intraguild prey

AbstractThe spatial distribution of predators is affected by intra‐ and interspecific interactions within the predator guild. Studying these interactions under fluctuating food availability, while taking habitat characteristics into account, offers a quasi‐experimental setup to determine the relative impact of con‐ and heterospecifics on reproductive success of predators. We analyzed the settlement decisions and reproductive success of Eurasian Pygmy Owls (Glaucidium passerinum) in the presence of both breeding conspecifics and their competitor and intraguild predator, Tengmalm's Owls (Aegolius funereus), under fluctuating abundance of their primary prey (voles). We used detailed data, collected across 11 years in a large study area (1300 km²), on the spatial and temporal variation of habitat characteristics in all available nesting sites, local densities of both species, and vole abundance. We found that Pygmy Owls strongly avoided breeding close to conspecifics but did not avoid Tengmalm's Owl nests. Nest box occupation of Pygmy Owls was positively correlated to the proportion of old spruce, mature and old pine forests, and farmlands, and occupation probability was higher at high vole abundance and in areas occupied in previous years. Pygmy Owl avoidance of conspecifics decreased when voles were abundant. At high conspecific density, Pygmy Owls showed lower hatching success and delayed hatching date, in agreement with the observed spatial avoidance. Finally, even though breeding Pygmy Owls did not spatially avoid Tengmalm's Owls, the density of heterospecifics correlated with low hatching and fledging success in Pygmy Owls. This suggests short term fitness costs when living close to competitors, even when lethal effects of intraguild interactions are subtle. Our results suggest that joint costs of exploitative and interference competition by Tengmalm's Owls, as well as intraguild predation, were lower than those induced by intraspecific competition only. This result might be due to the similar body size between the species considered, Tengmalm's Owls being only twice as large as Pygmy Owls. Interactions among con‐ and heterospecifics can therefore modify the spatial settlement and reproductive success of individuals on a landscape scale, also within the predator guild.

Breeding Behavior of Northern Saw-Whet Owls in Oregon

Abstract We know little about the breeding behavior of most nocturnal raptors. Nest attendance and prey delivery rates can be used as indices of relative habitat quality or extent of parental care. We used video cameras to document and observe prey delivery rates, nest attendance and bout durations at two northern saw-whet owl (Aegolius acadicus) nests in two artificial nest boxes in north-central Oregon. We collected 858 hours of video surveillance between 21 March and 01 June 2014. The number of prey deliveries per night increased as the nesting season progressed: 1.25 during laying, 1.33 during incubation, and 4.0 during the nestling phase. Prey was delivered most often between 2100 and 2200. Nest attendance by females was high during pre-laying (97.8%), laying (97.9%) and incubation (98.2%), but decreased during the nestling phase (55.7%). Nest attendance was higher during diurnal hours than nocturnal hours across all nesting phases. Duration of off bouts (recesses) was similar during pre-laying and l...

Accessible light detection and ranging: estimating large tree density for habitat identification

AbstractLarge trees are important to a wide variety of wildlife, including many species of conservation concern, such as the California spotted owl (Strix occidentalis occidentalis). Light detection and ranging (LiDAR) has been successfully utilized to identify the density of large‐diameter trees, either by segmenting the LiDAR point cloud into individual trees, or by building regression models between variables extracted from the LiDAR point cloud and field data. Neither of these methods is easily accessible for most land managers due to the reliance on specialized software, and much available LiDAR data are being underutilized due to the steep learning curve required for advanced processing using these programs. This study derived a simple, yet effective method for estimating the density of large‐stemmed trees from the LiDAR canopy height model, a standard raster product derived from the LiDAR point cloud that is often delivered with the LiDAR and is easy to process by personnel trained in geographic information systems (GIS). Ground plots needed to be large (1 ha) to build a robust model, but the spatial accuracy of plot center was less crucial to model accuracy. We also showed that predicted large tree density is positively linked to California spotted owl nest sites.

A Push-pull Protocol to Reduce Colonization of Bird Nest Boxes by Honey Bees.

Introduction of the invasive Africanized honey bee (AHB) into the Neotropics is a serious problem for many cavity nesting birds, specifically parrots. These bees select cavities that are suitable nest sites for birds, resulting in competition. The difficulty of removing bees and their defensive behavior makes a prevention protocol necessary. Here, we describe a push-pull integrated pest management protocol to deter bees from inhabiting bird boxes by applying a bird safe insecticide, permethrin, to repel bees from nest boxes, while simultaneously attracting them to pheromone-baited swarm traps. Shown here is an example experiment using Barn Owl nest boxes. This protocol successfully reduced colonization of Barn Owl nest boxes by Africanized honey bees. This protocol is flexible, allowing adjustments to accommodate a wide range of bird species and habitats. This protocol could benefit conservation efforts where AHB are located.

Phylogenetic relationships and terrestrial adaptations of the extinct laughing owl,Sceloglaux albifacies(Aves: Strigidae)

The taxonomic affinities of the monotypic owl genus Sceloglaux Kaup, 1848 have been widely debated. Here, we present a high-coverage mitogenome for the sole member of the genus, New Zealand's extinct laughing owl (Sceloglaux albifacies Gray, 1845), and assess its phylogenetic relationships. Our results provide strong support for Sceloglaux being nested within Ninox Hodgson, 1837, as sister taxon to the clade containing the barking owl (Ninox connivens Latham, 1801), Sumba boobook (Ninox rudolfi Meyer, 1882), and morepork (Ninox novaeseelandiae Gmelin, 1788). Accordingly, we synonymize Sceloglaux with Ninox, and recommend that the laughing owl hereafter be referred to as Ninox albifacies. Osteological analyses and a comparison of the wing and leg proportions of the laughing owl with those of other owls supports Gould's (1865) contention that it was largely a terrestrial owl, and predominantly caught prey on the ground. This is further supported by the relatively high abundance of terrestrial prey remains preserved in sediment deposits at former laughing owl nest sites.

Factors Influencing Burrowing Owl Abundance in Prairie Dog Colonies on the Southern High Plains of Texas

Large numbers of Western Burrowing Owls (Athene cunicularia hypugaea) nest in black-tailed prairie dog (Cynomys ludovicianus) colonies in the southern high plains of Texas. Because the Western Burrowing Owl is a species of concern with an uncertain future due to widespread extirpation of prairie dogs, we examined the roles of prairie dog colony size, burrow density, proxies of prey availability, and vegetative composition and structure on owl abundance and reproductive rate. The number of nesting Burrowing Owl pairs was positively correlated to colony area (r2 = 0.550, P = 0.006) and to number of prairie dog burrows in a colony (r2 = 0.733, P = 0.0230). Burrowing Owl numbers and reproductive rate (maximum number of young seen per successful pair) were not related to our measures of vegetative composition and structure in prairie dog colonies, nor to indices of prey availability.

Great Gray Owls Nesting in Atypical, Low-Elevation Habitat in the Sierra Nevada, California

Abstract Great Gray Owls (Strix nebulosa) in the Sierra Nevada were once believed to nest strictly within mid-elevation conifer forests in close proximity to montane meadows. However, recent observations of Great Gray Owls nesting at lower elevations suggest the lower-montane zone of the Sierra Nevada, where oak-dominated woodlands transition to conifer-dominated forests, may also provide habitat for this California-listed endangered species. We describe the reproductive success, apparent occupancy rate, and habitat associated with eight Great Gray Owl nests monitored between 2006–2014 on commercial timberlands in the lower-montane zone of the central Sierra Nevada, California. Reproductive success was high, with several breeding attempts producing three fledglings, and an average of 1.9 ± 0.9 young fledged during 21 breeding attempts. Apparent occupancy rates were also high (87.5% ± 20.9%) in the years following the discovery of a territory. Nests were in large-diameter (x¯ = 102.5 cm) trees, but sma...

Diet of a nesting pair of Long-eared Owls, Asio otus, in an urban environment in southwestern Turkey (Aves: Strigidae)

Pellets were collected under an active Long-eared Owl (Asio otus) nest in the city centre of Denizli, Turkey. The nest was located in a conifer tree in a 5.7 ha urban park, centrally-located in the city of Denizli, with a human population of 577,000 people. During April-June 2014, a total of 64 pellets containing remains of 86 individual prey items was found. All prey were Passeriformes and consisted of two species belonging to Passeridae and Hirundinidae. 78 of the 86 prey items (90.7%) were House Sparrow (Passer domesticus) and the other eight (9.3%) were House Martin (Delichon urbicum). This is one of the first studies to indicate that the Long-eared Owl's nesting season diet consists entirely of birds. The main factor affecting this result is probably the fact that the owls live in an urbanised setting.

Evaluating Desired Conditions for Mexican Spotted Owl Nesting and Roosting Habitat

The Mexican spotted owl (Strix occidentalis lucida) was listed as a threatened species in 1993, primarily because of concerns over the loss of late seral forest habitat to timber harvest and wildfire. A recovery plan prepared for this owl subspecies explicitly assumed that nesting (and/or roosting) habitat was a primary factor limiting distribution of Mexican spotted owls and provided four desired conditions for identifying and managing potential owl nesting/roosting habitat in forested habitat. We used data collected at nest sites of Mexican spotted owls in the Sacramento Mountains, New Mexico, to evaluate how well these desired conditions and associated forest structural attributes described nesting habitat in this area. All nest sites included in our analyses successfully fledged young during the study. These nest sites generally featured higher levels of the structural attributes included in the desired conditions (total basal area, density of trees >46 cm in dbh, percentage of basal area in trees 30 - 46 cm dbh, and percentage of basal area in trees >46 cm dbh) than the surrounding stand, yet only 46 - 87% of sampled nest sites met single desired conditions and only 22% met all four conditions simultaneously. The best generalized linear models using combinations of these four structural attributes plus canopy cover to distinguish between nest sites and random sites within owl home ranges all contained canopy cover and percentage of basal area in trees >46 cm dbh. Relative importance values were high for both of these attributes (1.000 and 0.983, respectively), and confidence intervals around parameter estimates included zero for all other attributes. The present combination of four desired conditions did not consistently identify nesting habitat in this area, required managing for levels of structural attributes that were greater than levels typically observed at successful owl nest sites, and did not include canopy cover, which was the single best predictor in the Sacramento Mountains. We recommend revising the desired conditions in the Sacramento Mountains to emphasize canopy cover and some attribute measuring the large tree component. We also recommend repeating this assessment in other geographic areas to determine how well the desired conditions for those areas describe nesting habitat for owls.

Gopherbusters? A Review of the Candidacy of Barn Owls as the Ultimate Natural Pest Control Option

Author(s): Kross, Sara M.; Baldwin, Roger A. | Abstract: While many raptor species consume rodent pests, the behaviors and habits of barn owls make them particularly suitable candidates for consideration as a viable pest control strategy. As a cavity-nesting species, barn owls will readily nest in man-made structures including nest boxes. Barn owls are also less territorial than many other raptor species and will tolerate other pairs nesting nearby if prey is abundant. Barn owls preferentially consume rodents including voles (Microtus spp.) and pocket gophers (Thomomys spp.) in habitats where they occur, but will also switch to more abundant prey so they may be able to sustain populations even if preferred prey numbers fall. These life-history traits allow for people to inflate barn owl populations in target areas, and this has been a factor in the widespread popularity of encouraging barn owls to nest in agricultural areas to provide natural pest control of small nocturnal vertebrate pests. However, the ability of barn owls to control rodent pests has only been formally tested in Malaysian rice and palm oil agriculture, and whether barn owls are capable of controlling rodent pests to economically acceptable levels in areas such as California is as yet unknown. We extracted and combined data from field studies of barn owl nesting behavior and diet in California vineyards to predict that annually, a pair of nesting barn owls and their progeny will consume 97.85 kg of prey. We predicted that an average barn owl nest in a California vineyard will therefore consume 843 pocket gophers, 578 voles, and 1,540 other prey items, most of which are mice. At these values, a barn owl population density of one nest/10 ha may be able to offset the annual productivity of an average population of pocket gophers, but even the highest barn owl densities of one nest/2 ha would be unable to control pocket gopher populations at maximum densities and reproductive rates. While valuable for making initial predictions of the ability of owls to control small rodent pests, our prediction methods are crude, and accurately assessing the capability of barn owls to control rodent pests will require more field data and more sophisticated modeling techniques.

Smart nest box: a tool and methodology for monitoring of cavity‐dwelling animals

SummaryCamera recording and video analysis have emerged as a successful non‐invasive method for collecting a wide range of biological data on many different taxa of animals. However, camera monitoring has rarely been applied to long‐term surveillance of cavity or box‐nesting species and ordinary off‐the‐shelf cameras are employed.We present methodology and data on the effectiveness of nest box monitoring using a camera system embedded in four ‘smart nest boxes’ (SNBoxes). We applied theSNBoxes to eight Tengmalm's owl (Aegolius funereus) nests in the Czech Republic during a 5‐month period in 2014. EachSNBox consisted of a pair of cameras with infrared lighting, an event detector, a radiofrequency identification reader, auxiliary sensors and a 60 Ah 12 V battery to power the whole system. All devices used were centrally managed by an embedded computer with specifically developed software.Using fourSNBoxes, we observed owl nesting continually during the incubation, nestling and fledgling phases, in total 309 days, resulting in 3382 owl video events. Batteries were changed every 6·5 days. A memory of 4 GB was found sufficient to store monthly data. We identified 12 types of male and female parental activities and their timing, the diet composition and frequency of prey delivery, the manner of prey storage, the light intensity at the time of each parental activity, the temperature inside the clutch and outside the box and the duration of nestling period of each young. We also produced a video on owl nesting for the general public.TheSNBox and related methodology show enormous potential as a non‐invasive tool for monitoring animals using boxes or natural cavities. The main advantage of theSNBox is the possibility to study both nocturnal and diurnal animal species and great flexibility in use of the software and hardware for different tasks. As a result, theSNBox provides an opportunity for novel insights into the breeding, roosting, hibernating, and food storage activities of a wide range of cavity‐living birds, mammals and reptiles.

Prey composition modulates exposure risk to anticoagulant rodenticides in a sentinel predator, the barn owl

Worldwide, small rodents are main prey items for many mammalian and avian predators. Some rodent species have pest potential and are managed with anticoagulant rodenticides (ARs). ARs are consumed by target and non-target small mammals and can lead to secondary exposure of predators. The development of appropriate risk mitigation strategies is important and requires detailed knowledge of AR residue pathways. From July 2011 to October 2013 we collected 2397 regurgitated barn owl (Tyto alba) pellets to analyze diet composition of owls on livestock farms in western Germany. 256 of them were fresh pellets that were collected during brodifacoum baiting. Fresh pellets and 742 liver samples of small mammals that were trapped during baiting in the same area were analyzed for residues of ARs. We calculated exposure risk of barn owls to ARs by comparing seasonal diet composition of owls with AR residue patterns in prey species. Risk was highest in autumn, when barn owls increasingly preyed on Apodemus that regularly showed AR residues, sometimes at high concentrations. The major prey species (Microtus spp.) that was consumed most frequently in summer had less potential to contribute to secondary poisoning of owls. There was no effect of AR application on prey composition. We rarely detected ARs in pellets (2 of 256 samples) but 13% of 38 prey individuals in barn owl nests were AR positive and substantiated the expected pathway. AR residues were present in 55% of 11 barn owl carcasses. Fluctuation in non-target small mammal abundance and differences in AR residue exposure patterns in prey species drives exposure risk for barn owls and probably other predators of small mammals. Exposure risk could be minimized through spatial and temporal adaption of AR applications (avoiding long baiting and non-target hot spots at farms) and through selective bait access for target animals.

Evaluating short‐ and long‐term impacts of fuels treatments and simulated wildfire on an old‐forest species

Fuels‐reduction treatments are commonly implemented in the western U.S. to reduce the risk of high‐severity fire, but they may have negative short‐term impacts on species associated with older forests. Therefore, we modeled the effects of a completed fuels‐reduction project on fire behavior and California Spotted Owl (Strix occidentalis occidentalis) habitat and demography in the Sierra Nevada to assess the potential short‐ and long‐term trade‐offs. We combined field‐collected vegetation data and LiDAR data to develop detailed maps of forest structure needed to parameterize our fire and forest‐growth models. We simulated wildfires under extreme weather conditions (both with and without fuels treatments), then simulated forest growth 30 years into the future under four combinations of treatment and fire: treated with fire, untreated with fire, treated without fire, and untreated without fire. We compared spotted owl habitat and population parameters under the four scenarios using a habitat suitability index developed from canopy cover and large‐tree measurements at nest sites and from previously derived statistical relationships between forest structure and fitness (λ) and equilibrium occupancy at the territory scale. Treatments had a positive effect on owl nesting habitat and demographic rates up to 30 years after simulated fire, but they had a persistently negative effect throughout the 30‐year period in the absence of fire. We conclude that fuels‐reduction treatments in the Sierra Nevada may provide long‐term benefits to spotted owls if fire occurs under extreme weather conditions, but can have long‐term negative effects on owls if fire does not occur. However, we only simulated one fire under the treated and untreated scenarios and therefore had no measures of variation and uncertainty. In addition, the net benefits of fuels treatments on spotted owl habitat and demography depends on the future probability that fire will occur under similar weather and ignition conditions, and such probabilities remain difficult to quantify. Therefore, we recommend a landscape approach that restricts timber harvest within territory core areas of use (~125 ha in size) that contain critical owl nesting and roosting habitat and locates fuels treatments in the surrounding areas to reduce the potential for high‐severity fire in territory core areas.

Subtle Gardeners: Inland Predators Enrich Local Topsoils and Enhance Plant Growth.

Inland vertebrate predators could enrich of nutrients the local top soils in the area surrounding their nests and dens by depositing faeces, urine, and prey remains and, thus, alter the dynamics of plant populations. Surprisingly, and in contrast with convincing evidence from coastal habitats, whether and how this phenomenon occurs in inland habitats is largely uncertain even though these habitats represent a major fraction of the earth's surface. We investigated during two consecutive breeding seasons the potential enrichment of the top-soils associated with inland ground-nesting eagle owls Bubo bubo, as well as its possible consequences in the growth of two common annual grasses in southern Spain. Top-soils associated with owl nests differed strongly and significantly from control top-soils in chemical parameters, mainly fertility-related properties. Specifically, levels of available phosphorus, total nitrogen, organic matter, and available potassium were 49.1, 5.6, 3.1, and 2.7 times higher, respectively, in top-soils associated with owl nests as compared to control top-soils. Germination experiments in chambers indicated that nutrient enrichment by nesting owls enhanced seedling growth in both annual grasses (Phalaris canariensis and Avena sativa), with seedling size being 1.4–1.3 times higher in owl nest top-soils than in control top-soils. Our experimental study revealed that pervasive inland, predatory birds can profoundly enrich the topsoil around their nests and, thus, potentially enhance local vegetation growth. Because diverse inland vertebrate predators are widespread in most habitats they have a strong potential to enhance spatial heterogeneity, impinge on plant communities, and exert an overlooked effect on primary productivity worldwide.

Diversity of great gray owl nest sites and nesting habitats in California

The great gray owl (Strix nebulosa) is listed by the state of California as endangered, with a population estimate of fewer than 300 individuals in the state. Nest-site availability has been suggested as a limiting factor for population growth in California, but information on nest types and nesting habitat has been based on a small number of nests that may not fully represent the variety of conditions used by the species. We collated all known nesting records in the Sierra Nevada mountains of California since 1973 (n=56) and then visited 47 of the nest sites to characterize habitat and compare them with paired reference sites. Great gray owls used a diversity of trees (8 species) and nest types. Although great gray owls in California are considered conifer-forest specialists, 30% of nests were in oak trees and 21% were below 1,000 m, which loosely corresponds to the lower conifer-zone limit. Across all elevations and tree species, degree of deterioration was the most important factor differentiating nest trees from paired reference trees at the same meadow, with nest trees being significantly more decayed. Nest trees (mean dbh = 100.5 ± SD 30.3 cm) were also significantly larger than reference trees. Canopy cover within 50m of nest trees (x = 85.1 ± 16.4%) was significantly greater at nest sites than at reference sites. At higher elevations, most nests were within 250m of a meadow edge, but at lower elevations, 31% of nests were >750m from the closest meadow. Based on these findings, we suggest that managers trying to promote great gray owl nesting maintain 4 or more large (100-cm dbh) snags per hectare in dense forests, especially near meadows. We also recommend increasing great gray owl survey effort in habitats and areas that may have been inadequately surveyed in the past. Published 2015. This article is a U.S. Government work and is in the public domain in the USA.

Range-wide analysis of northern spotted owl nesting habitat relations

Recently the US Fish and Wildlife Service, as part of a critical habitat analysis for the northern spotted owl (Strix occidentalis caurina), developed habitat suitability models based on thousands of owl nest sites distributed across 11 regions using the MaxEnt tool. Because these models formed the basis for critical habitat designations on millions of hectares of land, we undertook an independent evaluation of the FWS effort. We evaluated the accuracy of vegetation data used as input to develop the models, conducted out of sample analyses, correlated model output with owl reproductive success in two study areas, and developed alternate models using two different statistical methods. Vegetation data appeared accurate for only a few variables, and accuracy varied among model regions. Out of sample testing gave a high rate of classification errors and owl productivity was not correlated with MaxEnt model output in two study areas. Alternate statistical methods produced reasonable models with fewer variables. Critically, neither the models compared across regions nor the regions analyzed with different tools led to comparable use of variables. Thus biological interpretation of owl habitat selection models seemed ambiguous. In addition, for MaxEnt and one of the other tools, a highly significant trend by regression was found showing decreasing model accuracy as number of training nest sites increased. Together, these two results suggest that the generated models may be spurious to some unknown degree, perhaps because the underlying vegetation data, also derived from a model, are not sufficiently accurate to support the analysis and/or because the owls themselves affect habitat suitability by consuming their prey base. We suggest that the USFWS exercise caution in using MaxEnt models as a basis for regulatory purposes such as consultation, estimating likelihood of occupancy by owls, or evaluation of site-specific recovery actions.

Unusual Great Horned Owl Nest

Unusual Great Horned Owl Nest

Influence of anthropogenic features and traffic disturbance on burrowing owl diurnal roosting behavior

Birds that forage nocturnally should select daytime roosts that minimize predation risk to themselves, maximize their ability to warn mates or young about predators, and reduce their exposure to inclement weather. The objective of this study was to identify landscape features used by burrowing owls Athene cunicularia hypugaea during the day and to determine if traffic disturbance altered patterns of daytime space use. We tracked 17 adult male owls for 0.6 to 2.8 d each with GPS dataloggers and used resource utilization and resource selection functions to examine the response of each owl to nest burrows, perches, and roads. Selection for roads de - creased as average vehicle speed increased. Roads with vehicle speeds > 80 km h −1 were avoided. Owls may avoid roads with high traffic speeds because auditory disturbance from passing vehi- cles interferes with their ability to communicate the presence of predators to their mates and young. Owls also spent more time near fences and posts, likely because these elevated perches are good vantage points for predator detection. Perches near burrowing owl nests should be main- tained, and speed limits on roads near burrowing owl nests should be set to <80 km h −1 to help ensure owls are able to effectively detect and react to predators.

Social networks and ornithology studies: an innovative method for rapidly accessing data on conspicuous bird species

We developed an innovative method for finding individuals of a conspicuous species in complex urban habitats. The aim of this study was to detect as many burrowing owl nests as possible in order to develop an ecological and behavioral study. We performed an online survey through the social network, Facebook. The results of this survey allowed us to detect and locate 36 new burrowing owl nests. We conclude that developing online surveys through social networks is an innovative and cost-effective method to obtain information about bird locations, and can complement traditional methods such as field surveys.