Comparison of the mating systems and breeding behavior of a resident and a migratory tropical flycatcher

ABSTRACT.   Little is known about the genetic mating systems of tropical passerines and how they vary among species. We studied the Lesser Elaenia ( Elaenia chiriquensis ) and the Yellow-bellied Elaenia ( E. flavogaster ) near Gamboa, Panama. These species breed in the same habitat, but Lesser Elaenias are intratropical migrants with seasonal territories and Yellow-bellied Elaenias are permanent residents that remain paired and defend territories throughout the year. Lesser Elaenias exhibited greater breeding synchrony (15–18 %) than Yellow-bellied Elaenias (9–10%). For Lesser Elaenias, 10 of 15 (67%) nests contained extra-pair young and 14 of 38 (37%) young resulted from extra-pair fertilizations (EPFs). In contrast, only one extra-pair nestling (4%, N = 24 nestlings) was found in 13 Yellow-bellied Elaenia nests. Neither species exhibited strong mate guarding. The higher rate of EPFs in Lesser Elaenias is consistent with the hypothesis that year-round territorial tropical passerines with low breeding synchrony have little or no extra-pair behavior compared with species that breed seasonally. Although the low singing rates of Lesser Elaenias (7 songs/h) suggest that this not an important cue for female extra-pair mate choice, the role of conspicuous male dawn song remains to be investigated. Further studies of tropical passerines are needed to help disentangle the effects of synchrony, density, and other ecological and behavioral factors that have influenced the evolution of extra-pair mating systems in passerines.     

Asymmetrical Dependence Between a Neotropical Mistletoe and its Avian Seed Disperser

The degree of interdependence among interacting species has major implications for our understanding of the coevolutionary process and biodiversity maintenance. However, the mutualism strength among fruiting plants and their seed dispersers remains poorly understood in tropical ecosystems. We evaluated simultaneously the effectiveness of the avian seed dispersers of the mistletoe Struthanthus flexicaulis (Loranthaceae) and the contribution of its fruits to their diets in a highland rocky savanna in southeastern Brazil. The mistletoe fruits are small lipid‐rich pseudoberries available throughout the year. Four passerine birds fed on fruits, but Elaenia cristata (Tyrannidae) was the most effective disperser, responsible for more than 96 percent of the dispersed seeds. This bird swallowed fruits whole, expelling and depositing undamaged seeds by regurgitation and bill wiping on perches. From 646 dispersed seeds, 56 percent were deposited on safe sites, thin live twigs of 38 susceptible host species. Elaenia cristata were predominantly frugivorous, feeding on typically ornithocoric fruits of at least 12 species, but also on arthropods. Although fruits represented 75 percent of the feeding bouts along the year, S. flexicaulis fruits represented only 34 percent of the E. cristata diet. Our results highlight the asymmetrical nature of this mutualistic interaction, with the mistletoe life cycle locally linked to one highly effective seed disperser that is more weakly dependent on mistletoes fruits as a food source. We suggest that merging the seed dispersal effectiveness framework with diet assessment of seed dispersers is needed to clarify the asymmetries in mutualistic pairwise interactions involving plants and their animal partners.     

Phenological responses of plants to climate change in an urban environment

Global climate change is likely to alter the phenological patterns of plants due to the controlling effects of climate on plant ontogeny, especially in an urbanized environment. We studied relationships between various phenophases (i.e., seasonal biological events) and interannual variations of air temperature in three woody plant species (Prunus davidiana, Hibiscus syriacus, and Cercis chinensis) in the Beijing Metropolis, China, based on phenological data for the period 1962–2004 and meteorological data for the period 1951–2004. Analysis of phenology and climate data indicated significant changes in spring and autumn phenophases and temperatures. Changes in phenophases were observed for all the three species, consistent with patterns of rising air temperatures in the Beijing Metropolis. The changing phenology in the three plant species was reflected mainly as advances of the spring phenophases and delays in the autumn phenophases, but with strong variations among species and phenophases in response to different temperature indices. Most phenophases (both spring and autumn phenophases) had significant relationships with temperatures of the preceding months. There existed large inter- and intra-specific variations, however, in the responses of phenology to climate change. It is clear that the urban heat island effect from 1978 onwards is a dominant cause of the observed phenological changes. Differences in phenological responses to climate change may cause uncertain ecological consequences, with implications for ecosystem stability and function in urban environments.     

Counting Cats: The integration of expert and citizen science data for unbiased inference of population abundance

Free‐roaming animal populations are hard to count, and professional experts are a limited resource. There is vast untapped potential in the data collected by nonprofessional scientists who volunteer their time to population monitoring, but citizen science (CS) raises concerns around data quality and biases. A particular concern in abundance modeling is the presence of false positives that can occur due to misidentification of nontarget species. Here, we introduce Integrated Abundance Models (IAMs) that integrate citizen and expert data to allow robust inference of population abundance meanwhile accounting for biases caused by misidentification. We used simulation experiments to confirm that IAMs successfully remove the inflation of abundance estimates caused by false‐positive detections and can provide accurate estimates of both bias and abundance. We illustrate the approach with a case study on unowned domestic cats, which are commonly confused with owned, and infer their abundance by analyzing a combination of CS data and expert data. Our case study finds that relying on CS data alone, either through simple summation or via traditional modeling approaches, can vastly inflate abundance estimates. IAMs provide an adaptable framework, increasing the opportunity for further development of the approach, tailoring to specific systems and robust use of CS data.     

A critical review on some closely related species of <Emphasis Type="Italic">Tetranychus</Emphasis> sensu stricto (Acari: Tetranychidae) in the public DNA sequences databases

Taxonomic misidentification of the specimens used to obtain DNA sequences is a growing problem reported for different groups of organisms, which threatens the utility of the deposited sequences in public DNA databases. This paper provides new evidence of misidentifications in molecular DNA public databases in phytophagous mites of the Tetranychidae family belonging to the group Tetranychus (Tetranychus). Several species in this group are of economic and quarantine importance in agriculture and among them Tetranychus urticae, a highly polyphagous mite causing outbreaks in many crops worldwide, is certainly the most studied. We analyzed and evaluated the identity of 105 GenBank accessions of ITS2 rDNA and 138 COI mtDNA sequences which were deposited as T. urticae and those of 14 other taxa morphologically closely related to Tetranychus sensu stricto. In addition, ITS2 and COI sequences of 18 T. urticae samples collected for this study and identified by morphological criteria, were generated and included in the analyzed dataset. Among the deposited sequences in the GenBank database, numerous cases of apparently mistaken identities were identified in the group Tetranychus s. str., especially between T. urticae, T. cinnabarinus, T. kanzawai and T. truncatus. Unreliable sequences (misidentified or dubious) were estimated at nearly 30%. In particular the analysis supports the invalidity of the controversial species status of T. cinnabarinus. More generally, it highlights the need of using combined morphological and molecular approaches to guarantee solid species diagnostics for reliable sequence accessions in public databases.     

Desolation comes from the sky: Invasive Hymenoptera species as prey of Chilean giant robber flies (Diptera: Asilidae) through field observations and citizen science

Robber flies (Asilidae) are the main predatory fly family feeding on beetles, butterflies, other flies for true flies, and even spiders; however, Hymenoptera is the most common prey. Invasive Hymenoptera species are common in central and southern Chile; however, few predators of these are known. The hunting behavior and prey of Chilean robber fly species are also poorly known. The aim of this study is to provide the first hunting behavior records of five Chilean giant robber fly species on invasive Hymenoptera. In addition, an updated distribution of these species is provided. Records of hunting behavior were based on fieldwork collections and citizen science observations. The historical distribution was compared with citizen science observations using chi-square analyzes. Twelve predation events were recorded. Obelophorus terebratus was the most common predator. Bombus terrestris was the invasive Hymenoptera most preyed upon. Both the extension of occurrence of Lycomya germainii as Obelophorus species showed changes in his distribution. Only O. landbecki shown changes in area of occupancy. Citizen science is playing a key role in the knowledge of biological interactions and distribution of endemic and native Chilean robber fly species.     

Multiscale modeling of spring phenology across Deciduous Forests in the Eastern United States

Phenological events, such as bud burst, are strongly linked to ecosystem processes in temperate deciduous forests. However, the exact nature and magnitude of how seasonal and interannual variation in air temperatures influence phenology is poorly understood, and model‐based phenology representations fail to capture local‐ to regional‐scale variability arising from differences in species composition. In this paper, we use a combination of surface meteorological data, species composition maps, remote sensing, and ground‐based observations to estimate models that better represent how community‐level species composition affects the phenological response of deciduous broadleaf forests to climate forcing at spatial scales that are typically used in ecosystem models. Using time series of canopy greenness from repeat digital photography, citizen science data from the USA National Phenology Network, and satellite remote sensing‐based observations of phenology, we estimated and tested models that predict the timing of spring leaf emergence across five different deciduous broadleaf forest types in the eastern United States. Specifically, we evaluated two different approaches: (i) using species‐specific models in combination with species composition information to ‘upscale’ model predictions and (ii) using repeat digital photography of forest canopies that observe and integrate the phenological behavior of multiple representative species at each camera site to calibrate a single model for all deciduous broadleaf forests. Our results demonstrate variability in cumulative forcing requirements and photoperiod cues across species and forest types, and show how community composition influences phenological dynamics over large areas. At the same time, the response of different species to spatial and interannual variation in weather is, under the current climate regime, sufficiently similar that the generic deciduous forest model based on repeat digital photography performed comparably to the upscaled species‐specific models. More generally, results from this analysis demonstrate how in situ observation networks and remote sensing data can be used to synergistically calibrate and assess regional parameterizations of phenology in models.     

Latitudinal patterns in the phenological responses of leaf colouring and leaf fall to climate change in Japan

Aim  To estimate the potential effect of global climate change on the phenological responses of plants it is necessary to estimate spatial variations at larger scales. However, previous studies have not estimated latitudinal patterns in the phenological response directly. We hypothesized that the phenological response of plants varies with latitude, and estimated the phenological response to long-term climate change using autumn phenological events that have been delayed by recent climate change.
Location  Japan.
Methods  We used a 53-year data set to document the latitudinal patterns in the climate responses of the timing of autumn leaf colouring and fall for two tree species over a wide range of latitudes in Japan (31 to 44° N). We calculated single regression slopes for leaf phenological timing and air temperature across Japan and tested their latitudinal patterns using regression models. The effects of latitude, time and their interaction on the responses of the phenological timings were also estimated using generalized linear mixed models.
Results  Our results showed that single regression slopes of leaf phenological timing and air temperature in autumn were positive at most stations. Higher temperatures can delay the timing of leaf phenology. Negative relationships were found between the phenological response of leaves to temperature and latitude. Single regression slopes of the phenological responses at lower latitudes were larger than those at higher latitudes.
Main conclusions  We found negative relationships between leaf phenological responsiveness and latitude. These findings will be important for predicting phenological timing with global climate change.     

Mining citizen science data to explore stopover sites and spatiotemporal variation in migration patterns of the red-footed falcon

Citizen science data have already been used to effectively address questions regarding migration, a fundamental stage in the life history of birds. In this study, we use data from eBird and from 3 additional regional citizen science databases to describe the migration routes and timing of the red-footed falcon Falco vespertinus in the Mediterranean region across 8 years (2010–2017). We further examine the seasonal and yearly variation in migration patterns and explore sites used during the species migration. Our results suggest that the autumn passage is spatially less variable and temporally more consistent among years than in spring and that birds migrate faster in spring than in autumn. The species seems to be more prevalent along the Central Mediterranean during spring migration, probably as a result of the clockwise loop migration that red-footed falcons perform. There was a high variation in annual median migration dates for both seasons as well as in migration routes across years and seasons. Higher variation was exhibited in the longitudinal component thus indicating flexibility in migration routes. In addition, our results showed the species’ preference for lowlands covered with cropland and mosaics of cropland and natural vegetation as stopover sites during migration. Stopover areas predicted from our distribution modeling highlight the importance of the Mediterranean islands as stopover sites for sea-crossing raptors, such as the red-footed falcon. This study is the first to provide a broad-scale spatiotemporal perspective on the species migration across seasons, years and flyways and demonstrates how citizen science data can inform future monitoring and conservation strategies.     

Breeding phenological response to spring weather conditions in common Finnish birds: resident species respond stronger than migratory species

National bird‐nest record schemes provide a valuable data source to study large‐scale changes in basic breeding biology and effects of climate change on birds. Using nest‐record scheme data from 26 common Finnish breeding bird species from whole Finland, we estimated the laydate of the first egg for 129 063 nesting attempts. We then investigated the relationship of mean spring temperature and spring precipitation sum to changes in the onset of laying over the period 1961–2012. In addition, we examine differences in response to these climatic variables for species grouped for different life history strategies; migration, diet and habitat. Finally, we test whether body size is related to the strength of phenological response. We show that 26 common Finnish breeding bird species have advanced their laying dates over time and to an increase in the mean spring temperature over the study period. When species are grouped according life history strategies, we find that breeding phenological change is negatively associated with changes in the mean spring temperature where residents respond strongest to changes in mean spring temperature, but also short‐ and long‐distance migrants advance laydates with increasing spring temperatures. Breeding phenological change is also associated with spring precipitation, where resident species delay and short‐distance migrants advance the onset of breeding. In addition we find that omnivorous species respond stronger than insectivorous species to changes in spring temperature. In contrast to results from an earlier study, we do not find evidence that small‐sized species respond stronger to spring temperature than large‐sized species. As climate warming is predicted to continue in the future, long‐term citizen science schemes, such as the Finnish nest‐card scheme, prove to be a valuable cost‐effective way to monitor the environment and allow investigation into how species are responding to changes in their environment.     

Quality of citizen science data and its consequences for the conservation of skipper butterflies (Hesperiidae) in Flanders (northern Belgium)

Citizen science projects have become important data sources for ecologists. However, opportunistic data are not only characterized by spatial and temporal biases, but probably also contain species identification errors, especially concerning morphologically similar species. Such misidentifications may result in wrongly estimated distribution ranges and trends, and thus in inadequate conservation measures. We illustrate this issue with three skipper butterflies (Hesperiidae) in Flanders (northern Belgium) using photographs uploaded with observations in data portals. Ochlodes sylvanus and Thymelicus lineola records had relatively low identification error rates (1 and 11?%, respectively), but the majority (59?%) of Thymelicus sylvestris records turned out to be misidentified. Using verified records only allowed us to model their distribution more accurately, especially for T. sylvestris whose actual distribution area had hitherto been strongly overestimated. An additional field study on T. sylvestris confirmed the species distribution model output as the species was almost completely restricted to sites with verified records and was largely absent from sites with unverified records. The preference of T. sylvestris for unimproved grasslands was confirmed by the negative correlation between its model-predicted presence and elevated nitrogen and ammonia levels. Thus, quality control of citizen science data is of major importance to improve the knowledge of species distribution ranges, biotope preferences and other limiting factors. This, in turn, will help to better assess species conservation statuses and to suggest more appropriate management and mitigation measures.     

Evidence for longitudinal migration by a “sedentary” Brazilian flycatcher,the Ash‐throated Casiornis

The digitalization of museum collections and concurrent increase in citizen‐science initiatives is ushering in an era of unprecedented availability of primary biodiversity data. These changes permit a reappraisal of phenological patterns of tropical species. I examined spatio‐temporal variation in the distribution patterns of an ostensibly sedentary endemic Brazilian flycatcher, the Ash‐throated Casiornis (Casiornis fuscus), using both specimen data from museums and sighting records and rich media data from citizen‐science initiatives. I found compelling evidence for partial intratropical longitudinal migration to Amazonia and the Cerrado biomes from the species’ core range in the semi‐desert Caatinga biome and adjacent ecotones. These records from outside of the Caatinga were distributed during the height of the dry season from April to October, although the Caatinga is not entirely vacated at this time. This pattern of partial migration leads to a doubling of the distributional range of Ash‐throated Casiornises and strongly suggests that the species is a breeding near‐endemic of the Caatinga biome. This pattern was potentially previously not apparent because of significant biases in specimen collection between biomes, giving a false sense of abundance in the Brazilian Amazon.     

Hierarchical toolbox: Ensuring scientific accuracy of citizen science for tropical coastal ecosystems

Increased human population growth threatens the ecological functioning and goods and services provided by tropical coastal ecosystems. However, a lack of scientific baselines and resources hamper efforts to develop and monitor ecological indicators of environmental change. Citizen science can provide a cost and time effective solution, but needs considerable context specific development to ensure it provides valid information of the quality level required for acceptance by the scientific community. We reviewed the use of sampling methods for shore crabs as an example of an abundant tropical coastal organism with high citizen science suitability and ecological indicator capacity. We propose a hierarchical toolbox based on the distinction between rapid methods, allowing fast, noninvasive sampling by independent citizens, and medium speed methods allowing detailed but more invasive sampling requiring trained citizens working in close interaction with professionals. The hierarchical structure enables full use of the large scale data collection ability of citizen scientists at lower levels, while ensuring validation of errors at higher levels. Additionally, at each level, bias reduction and data validation measures can be employed. We conclude that citizen science methodologies can provide accurate large scale data to develop the ecological baselines urgently needed to monitor and manage environmental change in many tropical coastal ecosystems. We discuss a stepwise implementation of the toolbox leading to accuracy metadata which can be independently reviewed as an ultimate accuracy assessment and data integration mechanism among multiple projects.     

Improving and integrating data on invasive species collected by citizen scientists

Limited resources make it difficult to effectively document, monitor, and control invasive species across large areas, resulting in large gaps in our knowledge of current and future invasion patterns. We surveyed 128 citizen science program coordinators and interviewed 15 of them to evaluate their potential role in filling these gaps. Many programs collect data on invasive species and are willing to contribute these data to public databases. Although resources for education and monitoring are readily available, groups generally lack tools to manage and analyze data. Potential users of these data also retain concerns over data quality. We discuss how to address these concerns about citizen scientist data and programs while preserving the advantages they afford. A unified yet flexible national citizen science program aimed at tracking invasive species location, abundance, and control efforts could be designed using centralized data sharing and management tools. Such a system could meet the needs of multiple stakeholders while allowing efficiencies of scale, greater standardization of methods, and improved data quality testing and sharing. Finally, we present a prototype for such a system (see ).     

Flyway‐scale analysis reveals that the timing of migration in wading birds is becoming later

1. Understanding the implications of climate change for migratory animals is paramount for establishing how best to conserve them. A large body of evidence suggests that birds are migrating earlier in response to rising temperatures, but many studies focus on single populations of model species.
2. Migratory patterns at large spatial scales may differ from those occurring in single populations, for example because of individuals dispersing outside of study areas. Furthermore, understanding phenological trends across species is vital because we need a holistic understanding of how climate change affects wildlife, especially as rates of temperature change vary globally.
3. The life cycles of migratory wading birds cover vast latitudinal gradients, making them particularly susceptible to climate change and, therefore, ideal model organisms for understanding its effects. Here, we implement a novel application of changepoint detection analysis to investigate changes in the timing of migration in waders at a flyway scale using a thirteen‐year citizen science dataset (eBird) and determine the influence of changes in weather conditions on large‐scale migratory patterns.
4. In contrast to most previous research, our results suggest that migration is getting later in both spring and autumn. We show that rates of change were faster in spring than autumn in both the Afro‐Palearctic and Nearctic flyways, but that weather conditions in autumn, not in spring, predicted temporal changes in the corresponding season. Birds migrated earlier in autumn when temperatures increased rapidly, and later with increasing headwinds.
5. One possible explanation for our results is that migration is becoming later due to northward range shifts, which means that a higher proportion of birds travel greater distances and therefore take longer to reach their destinations. Our findings underline the importance of considering spatial scale when investigating changes in the phenology of migratory bird species.

     

Molecular taxonomy of Brazilian tyrant-flycatchers (Passeriformes: Tyrannidae)

The tyrannids are one of the most diverse groups of birds in the world, and the most numerous suboscine family in the Neotropics. Reflecting such diversity, many taxonomic issues arise in this group, mainly due to morphological similarities, even among phylogenetically distant species. Other issues appear at higher taxonomic levels, mostly brought up by genetic studies, making systematics a rather inconclusive issue. This study looks into the use of DNA barcodes method to discriminate and identify Tyrannidae species occurring in the Atlantic Forest and Cerrado biomes of Brazil. We analysed 266 individuals of 71 tyrant‐flycatcher species from different geographical locations by sequencing 542 bp of the mtDNA COI gene. The great majority of the analysed species showed exclusive haplotypes, usually displaying low intraspecific diversity and high interspecific divergence. Only Casiornis fuscus and Casiornis rufus, suggested in some studies to belong to a single species, could not be phylogenetically separated. High intraspecific diversity was observed among Elaenia obscura individuals, which can suggest the existence of cryptic species in this taxon. The same was also observed for Suiriri suiriri, considered by some authors to comprise at least two species, and by others to be divided into three subspecies. Additionally, the use of sequences from voucher specimens allowed us to correct four misidentifications that had happened in the field. Our findings suggest a great power of the COI barcodes to discriminate species of the Tyrannidae family that are found in Brazil.     

Using citizen science monitoring data in species distribution models to inform isotopic assignment of migratory connectivity in wetland birds

Stable isotopes have been used to estimate migratory connectivity in many species. Estimates are often greatly improved when coupled with species distribution models (SDMs), which temper estimates in relation to occurrence. SDMs can be constructed using point locality data from a variety of sources including extensive monitoring data typically collected by citizen scientists. However, one potential issue with SDM is that these data often have sampling bias. To avoid this potential bias, we created SDMs based on marsh bird monitoring program data collected by citizen scientists and other participants following protocols specifically designed to maximize detections of species of interest at locations representative of larger areas of inference. We then used the SDMs to refine isotopic assignments of breeding areas of autumn‐migrating and wintering sora Porzana carolina, Virginia rail Rallus limicola, and yellow rail Coturnicops noveboracensis based on feathers collected from individuals caught at various locations in the United States from Minnesota south to Louisiana and South Carolina. Sora were assigned to an area that included much of the western U.S. and prairie Canada, covering parts of the Pacific, Central, and Mississippi waterfowl Flyways. Yellow rails were assigned to a broad area along Hudson and James Bay in northern Manitoba and Ontario, as well as smaller parts of Québec, Minnesota, Wisconsin, and Michigan, including parts of the Mississippi and Atlantic Flyways. Virginia rails were from several discrete areas, including parts of Colorado, New Mexico, the central valley of California, and southern Saskatchewan and Manitoba in the Pacific and Central Flyways. Our study demonstrates extensive data from organized citizen science monitoring programs are especially useful for improving isotopic assignments of migratory connectivity in birds, which can ultimately lead to better informed management decisions and conservation actions.     

Integrating vibrational signals,mitochondrial DNA and morphology for species determination in the genus Aphrodes (Hemiptera: Cicadellidae)

Reliable delimitation and identification of species is central not only to systematics, but also to studies of biodiversity, ecology and pest management. In the era of Internet‐based biodiversity databases misidentifications are rapidly disseminated and may have far‐reaching consequences. Leafhoppers from the genus Aphrodes (Hemiptera, Cicadellidae) are common and abundant, but, nevertheless, they are still a taxonomically challenging group whose members are often assessed in ecological studies and are also potential vectors of plant diseases. Previous study has shown that the syntype series for A. aestuarina (Edwards) includes also specimens of A. makarovi Zachvatkin and has suggested that misidentifications may be widespread in museum collections. We studied Aphrodes individuals collected from the U.K. and Slovenia in order to provide a more comprehensive analysis of this genus using multiple criteria. Combined work using male and female vibrational signals emitted during courtship, and a 600‐bp fragment within the barcoding region of the COI mtDNA gene, provided validated specimens that we also used for morphometric study. Analyses confirmed A. aestuarina, A. bicincta, A. diminuta and A. makarovi as behaviourally, genetically and morphologically distinct species. Although any of these approaches could be used alone to distinguish between species, combining morphological and molecular approaches will help to improve reliability, especially when identifying females. Morphological investigation of validated individuals from the U.K. and Slovenia also revealed geographic differences within species. By combining several body and aedeagus morphological characters males can be reliably identified, however, morphological differences between species are, nevertheless, relatively small. By contrast, observed genetic distances between Aphrodes species are relatively large (4.2–7.0%). At about half of our collecting sites more than one Aphrodes species was found and A. makarovi was collected together with every other species, including A. aestuarina on tidal saltmarshes. Due to low morphological variation between syntopic congeners it is likely that many museum specimens of Aphrodes have been assigned to the wrong species and species identification in ecological and vector studies may also be questionable.     

Responses of sympatric canids to human development revealed through citizen science

Measuring wildlife responses to anthropogenic activities often requires long‐term, large‐scale datasets that are difficult to collect. This is particularly true for rare or cryptic species, which includes many mammalian carnivores. Citizen science, in which members of the public participate in scientific work, can facilitate collection of large datasets while increasing public awareness of wildlife research and conservation. Hunters provide unique benefits for citizen science given their knowledge and interest in outdoor activities. We examined how anthropogenic changes to land cover impacted relative abundance of two sympatric canids, coyote (Canis latrans), and red fox (Vulpes vulpes) at a large spatial scale. In order to assess how land cover affected canids at this scale, we used citizen science data from bow hunter sighting logs collected throughout New York State, USA, during 2004–2017. We found that the two species had contrasting responses to development, with red foxes positively correlated and coyotes negatively correlated with the percentage of low‐density development. Red foxes also responded positively to agriculture, but less so when agricultural habitat was fragmented. Agriculture provides food and denning resources for red foxes, whereas coyotes may select forested areas for denning. Though coyotes and red foxes compete in areas of sympatry, we did not find a relationship between species abundance, likely a consequence of the coarse spatial resolution used. Red foxes may be able to coexist with coyotes by altering their diets and habitat use, or by maintaining territories in small areas between coyote territories. Our study shows the value of citizen science, and particularly hunters, in collection of long‐term data across large areas (i.e., the entire state of New York) that otherwise would unlikely be obtained.