Urban areas promotes shifts in the proportion of prey consumed by four raptor species (Accipitridae) in Mexico

Introduction

Urbanization is an environmental change process linked to habitat loss and fragmentation, reduced connectivity between patches of native vegetation, and the introduction and proliferation of non-native species (Hansen et al., 2005). These environmental changes to the original habitat create specific conditions and resources within cities that can act as an ecological filter, excluding some species and favoring the presence of others, generating a process of biotic homogenization (McKinney, 2008; Silva, Sepúlveda & Barbosa, 2016). Urbanization can have adverse effects on raptors, including a decline in population densities, species richness, and eventually, local extinction (Kettel et al., 2018). In addition to habitat loss associated with urbanization, urban areas present threats to raptors such as collisions, electrocution, poisoning and disease (Solaro, 2018; Leveau et al., 2022). However, some raptor species can colonize, establish and thrive within urban areas; these raptors tend to be generalists with an opportunistic diet associated with the consumption of abundant prey in these areas (Boal & Dykstra, 2018). This could promote changes in the diet composition of raptors within urban areas; however, this has been poorly investigated in most raptor species (Ballejo & De Santis, 2013).

Diet analysis is one of the basic requirements for the understanding of the biology of species; it allows determining nutritional relationships, as well as their roles in the ecosystem (Royer et al., 2019; Zarei, Yazdi & Rajaee, 2021). Diet composition and prey consumption preferences of raptors can highlight their role as top predators and their effect on the population dynamics of their prey (Rectenwald et al., 2021), interspecific interactions with its competitors (Pande et al., 2018), intraspecific interactions between sexes (Panter & Amar, 2022), evidence of conservation risks (e.g., bioaccumulation of toxic substances or transmission of diseases; Ruiz-Suárez et al., 2014; Kunca, Smejkalová & Čepička, 2015), even this information is fundamental in rehabilitation and wildlife reintroduction processes (Arenas et al., 2020). Understanding the ecological functions of raptors and their interactions can help to better manage habitats and resources for their conservation (Mills, Soulé & Doak, 1993; Frixione & Rodríguez-Estrella, 2020). Historically, the study of raptor diet has been carried out by identifying the undigested remains of prey in pellets. However, this method tends to be limited to the breeding season and nesting sites where it is most feasible to collect pellets (Hiraldo et al., 1991). Recently, molecular techniques have been used that allow the accurate identification of raptor prey through the detection of DNA in fecess, pellets, or remains of prey from the surface of raptor beaks and talons (Bourbour et al., 2021; Hacker et al., 2021). However, both methods require the collection and processing of samples that can be difficult to obtain. Recently, the use of photographs available on citizen science platforms has been explored to determine the diet of raptors at broad spatial and temporal scales, complementing traditional approaches (Naude et al., 2019; Berryman & Kirwan, 2021; Panter & Amar, 2021, 2022; Kannan et al., 2023; Panter et al., 2024; Pantoja-Maggi, Medrano & Martínez, 2024).

The family Accipitridae is composed of 74 genera and between 250 and 255 species (Mindell, Fuchs & Johnson, 2018). Species within this family have a wide morphological variability that has allowed them to occur in a wide variety of habitats and exploit a wide range of resources (Winkler, Billerman & Lovette, 2020). The trophic niche of some accipitrids is generalized, feeding on a wide variety of prey (vertebrates and invertebrates); while other species specialize in the consumption of a specific type of prey (Winkler, Billerman & Lovette, 2020). In Mexico, there are 38 species belonging to Accipitridae (Chesser et al., 2024). However, most of the raptor species distributed in Mexico lack studies about their diet composition and their prey preferences. The research has been conducted in the north of the country analyzing the composition of pellets and has focused on the following raptor species: Osprey (Pandion haliaetus), Golden Eagle (Aquila chrysaetos), Bald Eagle (Haliaeetus leucocephalus), Burrowing Owl (Athene cunicularia), Peregrine Falcon (Falco peregrinus) and Aplomado Falcon (F. femoralis; Rodríguez-Estrella & Rivera-Rodríguez, 2006; Morales-Yañez, Rodríguez-Estrella & Gatica-Colima, 2023; Villalobos-Juárez et al., 2023). Additionally, there are isolated observations of different raptor species consuming prey previously unreported in the scientific literature (e.g., Rodríguez-Canseco et al., 2015; Nahuat-Cervera et al., 2020; Valencia-Herverth et al., 2022).

In this study, (1) we determined the diet composition of the following four species of accipitrids: Cooper’s Hawk (Astur cooperii), Common Black Hawk (Buteogallus anthracinus), Roadside Hawk (Rupornis magnirostris) and Gray Hawk (Buteo plagiatus). We selected these species due to their wide geographic distribution throughout Mexico and their contrasting natural histories. To achieve this, we use two sources of information: (1) data extracted from photographs available on citizen science platforms and (2) a search of scientific literature. (2) We determined the most preferred type of prey of each raptor species. (3) We compared whether the diet composition, the proportion of prey consumed and the trophic niche breadth of each species of raptor changed in urban and non-urban areas. (4) Finally, we evaluated whether the frequency of predation records by raptors changed throughout the year, with the type of prey or during breeding season.

In the context of biotic homogenization promoted by urbanization, we expect that (1) the prey type richness consumed by raptors will be lower in urban areas than in non-urban areas; (2) the proportion of prey consumed by raptors will be different in urban areas than in non-urban areas; (3) and the raptors trophic niche breadth will be more generalist in urban areas. Considering that the energy requirements of birds of prey are higher during the breeding season, and this may promote greater activity around the nest to provide food for the chicks (Eldegard et al., 2003; Panter & Amar, 2022), we expect the temporary increase in raptor predation records to be associated with their breeding season.

Materials AND methods

Results

We reviewed 27,923 photographic records, of which 18,717 records (67%) were reviewed in iNaturalist and 9,206 (33%) in Macaulay Library. The vast majority of these photographic records showed raptor species perching or flying. Our research did not include these photographic records because they did not show evidence of predatory interaction. Four photographic records could not be identified at a high taxonomic level, so they did not meet the criteria for inclusion in this study (Table S2). Only 356 (1%) photographic records met the criteria for inclusion in this research. These records covered a time period from January 2000 to December 2023. The number of records in iNaturalist and Macaulay Library by species included in this research was as follows: Cooper’s Hawk = 122 (34%), Common Black Hawk = 106 (30%), Roadside Hawk = 80 (23%) and Gray Hawk = 48 (13%). The literature review provided 45 predation records through 10 articles (Table S3). The number of records reported in the literature for each species was as follows: Cooper’s Hawk = 30 (67%), Common Black Hawk = 4 (9%), Roadside Hawk = 5 (11%) and Gray Hawk = 6 (13%). By gathering this information for the four raptor species from both sources of information, we obtained 401 predation records of 91 prey species in Mexico (Table S2 and S3). The sample coverage of predation interactions between raptors and their prey types had high levels of completeness for the four raptor species (Cooper’s Hawk = 1, Common Black Hawk = 0.99, Roadside Hawk = 0.97 and Gray Hawk = 0.98). On the other hand, the completeness of the recorded prey species was lower than the level of the type of prey (Cooper’s Hawk = 0.77, Common Black Hawk = 0.86, Roadside Hawk = 0.74 and Gray Hawk = 0.72). The geographic coverage of predation event records was variable among raptor species (Fig. 1, Table 1). Cooper’s Hawk was the species that had the least geographic coverage with predation records in 8% of the cells that covered its potential distribution (Fig. 1A, Table 1). On the other hand, Roadside Hawk was the species that had the greatest geographic coverage with predation records in 14% of the cells that covered its potential distribution in Mexico (Fig. 1C, Table 1). Some cells outside the distribution potential range of the species had predation records as follows: Cooper’s Hawk = 1 cell, Common Black Hawk = 3 cells, Roadside Hawk = 2 cells and Gray Hawk = 1 cell (Fig. 1).

The raptors studied consumed prey from all five vertebrate classes and three invertebrate subphyla (Fig. 2). The raptors consumed prey types in a proportion that was significantly different from what was expected (Cooper’s Hawk, Χ² = 210.57, df = 2, P < 0.0001; Common Black Hawk, Χ² = 113.75, df = 6, P < 0.0001; Roadside Hawk, Χ² = 139.41, df = 6, P < 0.0001 and Gray Hawk, Χ² = 33.59, df = 4, P < 0.0001). All raptors had a preferred type of prey; that is, we found significantly more records of the consumption of that prey type than the other prey types: Cooper’s Hawk consumed significantly more birds than other prey (mammals P < 0.0001; reptiles P < 0.0001). Common Black Hawk consumed similar proportions of fishes and crustaceans (P = 0.05) but consumed significantly more fishes than other prey (amphibians, P < 0.0001; birds P < 0.0001; insects = P < 0.0001; mammals P < 0.0001; reptiles P = 0.007). Gray Hawk consumed similar proportions of reptiles and birds (P = 0.71), reptiles and mammals (P = 0.49) but consumed significantly more reptiles than amphibians (P < 0.001) and crustaceans (P < 0.001). Roadside Hawk consumed significantly more reptiles than other prey (amphibians P < 0.0001; birds P < 0.0001; crustaceans P < 0.0001; insects P < 0.0001; mammals P < 0.0001 and myriapods P < 0.0001; Table S3, Fig. 2).

The distance between raptor predation records and the nearest human settlement ranged from 0 to 36.4 km (Cooper’s Hawk, the range was 0 to 25.6 km; Gray Hawk, 0 to 16.9 km; Common Black Hawk, 0 to 28 km; and for Roadside Hawk, 0 to 36.4 km; Table S2 and Fig. S1). Most records of predation by Common Black Hawk (urban areas = 23 records, non-urban areas = 87 records; Fig. 3B), Roadside Hawk (urban areas = 28 records, non-urban areas = 57 records; Fig. 3C), and Gray Hawk (urban areas = 18 records, non-urban areas = 36 records; Fig. 3D) occurred in non-urban areas. On the contrary, most records of predation by Cooper’s hawks occurred within urban areas (urban areas = 79 records, non-urban areas = 73 records; Fig. 3A). The number of predation records by Cooper’s Hawk was higher in urban areas than in non-urban areas (Mann–Whitney = 33.5, z = 2.21 (non-urban = 73, urban = 79), P = 0.024; Fig. 4A). In contrast, the number of predation records was higher in non-urban areas than in urban areas for Common Black Hawk (Mann–Whitney = 15, z = 3.28 (non-urban = 87, urban = 23), P < 0.001; Fig. 4B), Roadside Hawk (Mann–Whitney = 34.5, z = 2.15, (non-urban = 57, urban = 28), P = 0.029; Fig. 4C) and Gray Hawk (Mann–Whitney = 38, z = 2.03, (non-urban = 36, urban = 18), P = 0.041; Fig. 4D). The richness of prey types consumed by Cooper’s Hawk and Gray Hawk remained constant in urban and non-urban areas (Figs. 5A and 5D). In contrast, fewer prey types were consumed by Common Black Hawks and Roadside Hawks in urban areas than in non-urban areas (Figs. 5B and 5C). The proportion of prey types consumed in urban and non-urban areas changed significantly for Cooper’s Hawk (Χ² = 15.6, df = 2, P = 0.0004; Fig. 5A), Roadside Hawk (Χ² = 21.75, df = 6, P = 0.0005; Fig. 5C), and Gray Hawk (Χ² = 56.07, df = 4, P < 0.0001; Fig. 5D). Conversely, the proportion of prey types consumed by Common Black Hawk’s was similar in urban and non-urban areas (Χ² = 5.83, df = 6, P = 0.46; Fig. 5B). The trophic niche breadth of Common Black Hawk (urban areas = 0.67, non-urban areas = 0.39), Roadside Hawk (urban areas = 0.44, non-urban areas = 0.24), and Gray Hawk (urban areas = 0.60, non-urban areas = 0.48) was broader in urban areas than in non-urban areas. In contrast, Cooper’s Hawk had a narrow trophic niche breadth in urban areas than in non-urban areas (urban areas = 0.03, non-urban areas = 0.27).

GLMs indicated that the frequencies of predation records by raptors were differentially associated with the month of the year, the type of prey consumed and breeding season (Table 2, Fig. 6). The highest frequency of predation records by Roadside Hawk occurred during their breeding season (Table 2, Fig. 6C). In contrast, the highest frequency of predation records by Cooper’s Hawks occurred during their non-breeding season (Table 2, Fig. 6A). On the other hand, the frequency of predation records by Common Black Hawks and Gray Hawk was independent of their breeding season (Table 2, Figs. 6B and 6D). Monthly records of Common Black Hawk on citizen science platforms were correlated with monthly predation records (Spearman r = 0.71, N = 12, P = 0.008; Fig. 6B). However, there was no correlation between monthly records on citizen science platforms and monthly predation records by Cooper’s Hawk (Spearman r = 0.53, N = 12, P = 0.07; Fig. 6A), Roadside Hawk (Spearman r = −0.22, N = 12, P = 0.48; Fig. 6C) and Gray Hawk (Spearman r = −0.26, N = 12, P = 0.40; Fig. 6D).

Discussion

Research into the diet of raptors has important implications for their conservation, as it affects the maintenance of their populations, their health, and even the population dynamics of their prey (Boal, 2018; McClure et al., 2018). However, little attention has been paid to the diet composition of raptors inhabiting urban areas. In this study, we determined the diet composition of four raptors and compared whether it changed in urban and non-urban areas of Mexico. To achieve this, we created a dataset using data extracted from a literature review and photos available on citizen science platforms. Our dataset of predation interactions between raptors and their prey types had high range of sample coverage, from 0.97 to 1. This means that the information extracted from photographs on citizen science platforms allowed us to determine with a high degree of certainty the composition of the diet of raptors in terms of the types of prey consumed (Fig. 2). In addition, this high coverage of the dataset allows us to infer the preferences of raptors for preying on certain types of prey. Cooper’s Hawk consumed significantly more birds than other prey. This is consistent with what was reported in other locations throughout its the geographical distribution (Kennedy & Johnson, 1986; Hiraldo et al., 1991; Roth & Lima, 2003; Rosenfield et al., 2024). The Common Black Hawk showed a clear preference for preying on crustaceans and fishes; both types of prey have been reported as the most commonly consumed prey by this species (Johnson & Schnell, 2024). Roadside Hawk consumed significantly more reptiles than other prey. The diet of this species is reported to be generalist and highly opportunistic, and its preference for preying on certain types of prey varies widely throughout its geographical distribution (Bierregaard, Boesman & Kirwan, 2024). However, reptiles often compose an important part of their diet (Panasci & Whitacre, 2000). Gray Hawk did not have a clear preference for preying on one type of prey; this species preyed on reptiles, birds, and mammals in similar proportions. Our results are consistent with previous reports, which indicate that the species’ diet consists mainly of vertebrates, particularly reptiles, birds, and mammals (Bibles, Glinski & Johnson, 2020). On the other hand, the sample coverage at the species level of prey consumed by raptors was a range of sample coverage from 0.72 to 0.86. These results highlight the effectiveness of our dataset in identifying prey even at low taxonomic levels (see Table S2) and the complexity of the diet of the studied raptors and their great ability to include opportunistically new prey items in their diet (Jaksić & Braker, 1983).

The geographic coverage of predation records for the four raptor species was low. Only 8–14% of the cells that covered the potential distribution of raptors in Mexico had records of predation events (Fig. 1, Table 1). However, the cells with predation records were dispersed latitudinally and longitudinally over most of the potential geographic range of the four raptor species, i.e., the records covered a wide variety of localities facilitating the recording of greater prey richness. Also, we were able to detect regions of the country with a lack of records of predation events. Particularly, in the northwestern of the country (Sonora and Sinaloa) we found no records of Cooper’s Hawk predation events. Also, the coasts of the states of Guerrero and Michoacán lack records of consumed prey by Gray Hawk and Common Black Hawk. In the case of the Roadside Hawk, the absence of records extends to the coasts of Guerrero, Michoacán, Colima, and Jalisco. This highlights the importance of conducting research in these locations, as well as promoting social participation in citizen science platforms in these regions to expand knowledge of these species diets and their local dietary preferences.

Although most of our data comes from citizen science platforms, our dataset did not show a spatial bias toward urban areas (see Table S2 and Fig. S1). Therefore, our results accurately reflect the diets of the studied raptors and their dietary shifts in urban areas in Mexico. Contrary to our expectations, the richness of prey types consumed by Cooper’s Hawk and Gray Hawk remained constant in urban and non-urban areas. The diet of both species is based on the consumption of reptiles, birds, and mammals (Figs. 2, 5A, and 5D). Some species of these types of prey are characterized by being human-commensals and respond favorably to urbanization such as pigeons, rats, and even some lizards (Chace & Walsh, 2006). These species can take advantage of direct food supplementation through bird feeders, waste generated by the human population or artificial lights that attract and concentrate high abundance of invertebrates (Chace & Walsh, 2006; Putman & Tippie, 2020). The abundance and availability of these prey within cities allowed the richness of prey types consumed by both raptors to remain stable in urban areas. In contrast, and as we expected, the richness of prey types consumed by Common Black Hawk and Roadside Hawk was lower in urban areas than in non-urban areas. Both raptors consumed seven types of prey in non-urban areas and only five types of prey in urban areas (Figs. 5B and 5C). The types of prey that were not consumed in urban areas by these raptors were one class of vertebrates (mammals) and three subphyla of invertebrates (crustaceans, myriapods, and insects). Urbanization acts as an ecological filter that promotes a reduction in species richness and biotic homogenization through the increase in the abundance of generalist species that exploit resources and conditions within urban areas (McKinney, 2008). These changes in the richness and abundance of available prey lead raptors to shift the composition of their diet to abundant prey (Boal, 2018; Leveau et al., 2022). However, the decrease in the richness of prey types consumed by Common Black Hawk and Roadside Hawk in urban areas did not significantly alter the diet composition of these species, as these prey had very low proportion of consumption in non-urban areas (1–2% of the proportion of prey consumed, Figs. 5B and 5C).

As we expected, the proportion of prey types consumed by Cooper’s Hawk, Roadside Hawk, and Gray Hawk was significantly different in urban areas than in non-urban areas (Figs. 5A, 5C, and 5D). In contrast, the proportion of prey types consumed by Common Black Hawk was similar in urban and non-urban areas (Fig. 5B). Regardless of their preference for consuming a particular type of prey, the four raptors studied increased the proportion of bird consumption in urban areas (Fig. 5). The increase in the proportion of bird consumption was from 2% to 36% (Fig. 5), with the Common Black Hawk showing the smallest increase in bird consumption (2%) and the Gray Hawk showing the highest increase in bird consumption in urban areas (36%). This pattern is consistent with previous reports indicating that some species raptors increase the proportion of birds they consume in urban areas, while reducing the proportion of other types of prey, such as mammals or invertebrates (Ballejo & De Santis, 2013; Sumasgutner et al., 2014). The increase in bird consumption in urban areas could be related to the following factors: the high abundance of some exotic species such as pigeons (Columba livia), Starlings (Sturnus vulgaris) or sparrows (Passer domesticus, Jaksić & Braker, 1983; Cava, Stewart & Rosenfield, 2012), the constant food supplies lead to the increase in the biomass of some bird species (Chace & Walsh, 2006), and the ease of hunting birds that are attracted to artificial feeders (McCabe et al., 2018). An important component in the diet of raptors in urban areas is the consumption of exotic bird species (Cava, Stewart & Rosenfield, 2012). This implies that the establishment and persistence of raptor populations in urban areas could help regulate the populations of exotic bird species. However, it has been reported that some raptors tend to have higher rates of Trichonomiasis in urban areas than in non-urban areas due to the consumption of infected birds (Boal & Mannan, 1999). The prevalence of the disease could be higher in urban areas due to the use of feeders by infected birds. The increase in the proportion of bird consumption in urban areas could increase the exposure of raptors to the disease and lead to a higher mortality rate, affecting the conservation of their populations. This highlights the need for research focused on assessing the prevalence of Trichomoniasis in urban bird and raptor populations. On the other hand, the proportion of prey consumed by Common Black Hawk was similar in urban and non-urban areas. This can be explained by the strong preference of this raptor for habitats associated with water bodies (Johnson & Schnell, 2024). These habitats are associated with the availability and abundance of their preferred prey (fishes and crustaceans; Figs. 2 and 5B). This suggests that this species will only occur in human settlements that meet these habitat and food requirements, which would imply areas with low or intermediate levels of urbanization. This is consistent with the findings of Boal (2018), who reports that raptor species most closely associated with urban areas will have a broad food-niche and a preference for more closed habitats such as forests.

As we expected the trophic niche breadth of Common Black Hawk, Roadside Hawk and Gray Hawk was broader in urban areas than in non-urban areas. Boal (2018) reports that trophic niche breadth of raptors tends to be broader in urban areas. In this study the raptors maintained or consumed fewer prey types in urban areas. In addition, all studied raptors increased the proportion of birds consumed in urban areas. The trophic niche breadth is determined by the availability of local resources (Jaksić & Braker, 1983). In urban areas, the high availability of birds and their aggregation around feeders makes it easier for raptors to hunt them. These factors lead to a more equitable distribution of prey consumption in urban areas and a more generalized diet. Contrary to our expectations, Cooper’s Hawk had a narrow trophic niche breadth in urban areas than in non-urban areas. Cooper’s Hawk has a diet specialized in consuming birds. The abundance and constant availability of birds in urban areas allows Cooper’s Hawk to consume more birds in urban areas than in non-urban areas.

Temporal variation in the frequency of predation records was influenced by differential factors depending on the species of raptor. The monthly proportion of consumption of different types of prey varied throughout the year. This variability could highlight changes in energy requirements mainly associated with the breeding season, particularly egg laying and chick rearing, as their high growth rate demands more energy (Catry et al., 2016). Similarly, these seasonal changes in diet could reflect the natural dynamics of prey abundance and availability in the environment (Cava, Stewart & Rosenfield, 2012; Garcia-Heras et al., 2017). Only Roadside Hawk met our expectations, as the frequency of its predation records increased during the months of its breeding season (Table 2, Fig. 6C). It has been reported that in this species, the prey delivery rate to chicks in the nest ranges from 0.26 to 0.43 prey/hour/chick (Panasci & Whitacre, 2002). This implies constant activity around the nest generated by continuous provisioning by both parents. This increased activity in a specific location (within the territory and at the nest) could facilitate the photographic recording of these predation events. In contrast, Cooper’s Hawk showed the opposite pattern, as the highest frequency of its predation records occurred during the non-breeding season (Table 2, Fig. 6A). It has been reported that in avian predatory raptors, the size of their prey decreased during their breeding season (Newton & Marquiss, 1982; Panter & Amar, 2022). The coincidence of the breeding season of these raptors and the emergence of passerine fledglings could explain this change in prey size selection (Newton & Marquiss, 1982). The main source of our data was photographic records on citizen science platforms. This source of information is biased toward the recording of predation on large prey, as their identification at lower taxonomic levels is usually possible and their handling time is longer, which facilitates the photographic recording of the predation event (see study limitations). The change in prey size selection during the breeding season of Cooper’s Hawks may have limited the number of predation event records, resulting in a higher number of predation event records during the non-breeding season. On the other hand, the monthly variation in Common Black Hawk predation records showed a correlation with the number of monthly photographic records on citizen science platforms. The activity of observers who upload their photographic records to citizen science platforms can vary throughout the year. Holiday seasons or initiatives such as Global Big Day can generate a temporary increase in photographic records on these platforms. Research based on citizen science records should consider this possibility, especially when evaluating patterns of frequency of records, since the activity of users of these platforms could be a factor that obscures the ecological patterns being evaluated. The variation in Gray Hawk’s monthly predation records did not show a pattern associated with prey type, breeding season, or citizen science platform presence records. The low number of predation records for this species may have prevented us from detecting a clear pattern that we can associate with the temporal changes in its diet. On the other hand, the generalist and opportunistic diet of the species (Bibles, Glinski & Johnson, 2020) may prevent us from detecting a clear pattern in the monthly variability of its diet. In particular, Gray Hawk and Common Black Hawk had low numbers of predation events within urban areas. This can be explained by their association with certain habitat characteristics (forested areas and bodies of water, respectively) or by their preferred prey (reptiles, and fish, and crustaceans, respectively). The low number of predation events in urban areas may have prevented us from identifying temporal patterns related to the breeding season. Future research could focus on evaluating how the reproductive activity of both species promotes temporal variability in predation records.

Conclusions

The analysis of information obtained from photographic records available on citizen science platforms, as well as the compilation of data published in the scientific literature, allowed us to determine with a high degree of certainty the diet composition of the four raptor species on a broad geographic scale. The effect of urban areas on the richness and proportion of prey consumed by raptors differed among the species studied. The richness of prey types consumed by Cooper’s Hawk and Gray Hawk remained constant in urban and non-urban areas. However, the richness of prey types consumed by Common Black Hawk and Roadside Hawk was lower in urban areas than in non-urban areas. The proportion of prey types consumed by Cooper’s Hawk, Roadside Hawk, and Gray Hawk was significantly different in urban areas than in non-urban areas. In contrast, the proportion of prey types consumed by Common Black Hawk was similar in urban and non-urban areas. The trophic niche breadth of raptors was broader in urban areas than in non-urban areas, except for Cooper’s hawks, which had a narrow trophic niche breadth in urban areas than in non-urban areas. This is associated with Cooper’s Hawk preference for feed on birds. The four raptors studied increased the proportion of bird consumption in urban areas. This change in the proportion of bird consumption in urban areas could imply a risk to the conservation of raptor populations due to the higher prevalence of diseases transmitted through the consumption of infected birds. This highlights the need for research focused on assessing the prevalence of diseases that pose a risk to the conservation of birds and raptors in urban areas.

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