What makes a species tolerant to urbanization? : risk behavior and pace of life in urban birds of the Metropolitan Area of Mendoza, Argentina

La expansión urbana hacia áreas rurales y naturales es un proceso global. Las ciudades difieren de los entornos naturales, entre otras cosas, en niveles de actividad humana, y disminución de depredadores naturales. Por ello es importante entender qué es lo que permite que algunas especies vivan en entornos altamente urbanizados mientras que otras no pueden hacerlo. La teoría del síndrome del ritmo de vida sostiene que ante condiciones ambientales variables, animales con ritmos de vida contrastantes, (i. e. de vida rápida vs. de vida lenta) difieren en sus respuestas conductuales y fisiológicas (Wolf et al. 2007; Réale et al. 2010). Cómo los animales de vida lenta priorizan la persistencia futura sobre la reproducción presente deben ser más reacios a asumir riesgos que los animales de vida rápida. Las últimas evidencias empíricas sugieren sutiles modificaciones a esta teoría ya que muestran que este síndrome es muy dependiente de la masa corporal (i. e. especies pequeñas: vida rápida, especies grandes: vida lenta) y del contexto ambiental. En entornos naturales las especies de vida lenta tienden a ser más reacias al riesgo que las especies de vida rápida pero en entornos urbanos las especies de vida lenta son menos reacias al riesgo que en entornos naturales (Sol et al. 2018). Así ante cambios ambientales rápidos los animales de vida rápida serían más incapaces de cambiar que los animales de vida lenta y que en entornos urbanizados los animales de vida lenta permitirán aproximaciones más cercana por los humanos. En el Área Metropolitana de Mendoza las palomas Patagioenas maculosa (308-347gr), Zenaida auriculata (102-125gr) y Columbina picuí (42-59gr) muestran un continuo de vida lento, intermedio y rápido respectivamente. Nuestra hipótesis es que las especies de palomas de vida lenta e intermedia ajustan sus distancias de iniciación del vuelo (FID) según su percepción del riesgo, pero la especie de vida rápida no. Nuestros objetivos son: (1) estimar las FIDs de las poblaciones urbanas y periurbanas de P. maculosa, Z. auriculata y C. picuí, (2) comparar FIDs entre poblaciones urbanas y periurbanas de P. maculosa, Z. auriculata, C. picuí; (3) Indagar si P. maculosa y Z. auriculata ajustan sus FIDs entre zonas urbanas y periurbanas. Predecimos: (1) las poblaciones urbanas de P. maculosa y Z. auriculata tendrán FIDs menores que las poblaciones periurbanas; (2) no habrá diferencias en los FIDs entre las poblaciones urbanas y periurbanas de C. picui.Urban expansion into rural and natural areas is a global process. Cities differ from natural environments among other things in levels of human activity, availability of food, decrease of natural predators. In view of this it is important to understand what it is that allows some species to live in highly urbanized environments while others can not. The theory of the pace-of- life syndrome maintains that in the face of variable environmental conditions, animals with contrasting pace-of- live (i. e. fast-lived vs. slow-lived) differ in their behavioral and physiological responses (Wolf et al., 2007, Réale et al., 2010). As slow-lived animals prioritize future over current reproduction they should generally be more risk-averse compared to those at the fast extreme. The latest empirical evidence suggests subtle modifications to this theory since they show that this syndrome is very dependent on body mass (i. e. small species: fast life, large species: slow life) and the environmental context. In natural environments, slow-living species tend to be more risk-averse than fast-living species, but in urban environments, slow-living species are less risk-averse than in natural environments (Sol et al. 2018). This suggests that in the face of rapid environmental changes, fast-living animals would be more unable to change than slow-living animals and that in urbanized environments, slow-living animals would allow a closer approximation by humans. In Mendoza Metropolitan Area (MMA) Patagioenas maculosa (308-347gr), Zenaida auriculata (102-125gr) and Columbina picuí (42-59gr), (i. e. pigeons), represent a continuum of slow, intermediate and fast life, respectively. Our hypothesis is that slow and intermediate-lived species of pigeons adjust their flight initiation distances (FID) according to their perception of risk, but the fast-living species do not. Our objectives are: (1) to estimate FIDs of urban and peri-urban populations of P. maculosa, Z. auriculata and C. picuí in MMA parks; (2) compare FIDs between urban and peri-urban populations of P. maculosa, Z. auriculata and C. picuí. (3) Inquire whether P. maculosa and Z. auriculata adjust their FIDs between urban and peri-urban areas. We predict that: (1) urban populations of P. maculosa and Z. auriculata will have smaller FIDs than peri-urban populations and that (2) there will be no differences in FIDs between the urban and peri-urban populations of C. picui

Do biological traits of birds predict their occupation of an urbanization gradient in Mendoza Metropolitan Area?

Estudiamos las variaciones espacio-temporales de ensambles de aves en parques de un gradiente urbano del Área Metropolitana de Mendoza (AMM), Argentina. Suponiendo que la urbanización filtra las especies del pool regional según sus rasgos biológicos, definimos especies tolerantes y evasoras urbanas según tuvieran, al menos, cuatro de los seis rasgos propios de cada categoría. Predijimos que las tolerantes alcanzan densidades máximas en matriz urbana o urbana-suburbana y las evasoras, en matriz periurbana o periurbana suburbana. En las estaciones reproductiva y no reproductiva de 2017 y 2018 registramos las aves en transectas de faja en las tres matrices. Los resultados apoyaron la idea y permitieron identificar dos filtros ambientales: uno entre el AMM y su entorno que permite el ingreso de especies tolerantes urbanas frecuentes, y otro en el centro de la ciudad que impide el ingreso de evasoras infrecuentes mientras prevalecen las tolerantes urbanas. Se ha hipotetizado que los núcleos urbanos sostienen pocas especies muy abundantes y que los ambientes intermedios alojan mayor riqueza específica. Estimamos abundancia y riqueza en las tres matrices, pero no encontramos ni mayor abundancia en la matriz urbana ni mayor riqueza en la matriz suburbana. Esto podría deberse a que la matriz suburbana ofrece un ecotono muy restringido dentro del AMM. La plausible mayor estabilidad climática y de recursos en el centro de las ciudades no se asoció en Mendoza con ensambles más estables estacional o interanualmente. Los rasgos biológicos permiten identificar distintos filtros ambientales a la par que predicen y explican la ocupación espacial de numerosas especies de aves. Algunos de nuestros resultados destacan la importancia de los parques urbanos respecto a las calles linderas como espacios que atenúan los efectos de la urbanización sobre las aves, información valiosa para planes de desarrollo urbano sustentable.We studied the spatial and temporal dynamics of bird assemblages in parks located within an urban gradient of the Mendoza Metropolitan Area (AMM), Argentina. Under the assumption that urbanization filters the species from the regional pool according to their biological traits, we defined tolerant and urban avoider species as those having at least four up to six traits of every category, and predicted that urban tolerant species reach maximum densities in urban or urban-suburban matrixes, whereas avoiders species are more abundant in peri-urban or peri-urban-suburban matrixes. In breeding and non-breeding seasons of 2017 and 2018, we recorded birds on strip transects on the three matrixes. Our results supported the idea and allowed the identification of two environmental filters: one located between the AMM and its surroundings, which admits urban-tolerant common species, and other in downtown Mendoza, which prevents the access of infrequent urban avoiders and maintains several urban tolerant species. Under the hypothesis that urban centers support few very abundant species and that more intermediate habitats host the greatest species richness, we estimated total abundance and richness in the same matrixes, but we find neither greater abundance in the urban matrix nor greater richness in the suburban matrix. These results could be related to the fact that the suburban matrix offers a very restricted ecotone within the AMM. The plausible higher stability of climate and resource supply in downtown Mendoza was not associated with more temporal stability of bird assemblages. Biological traits allow to identify significant environmental filters while predicting and explaining the spatial occurrence of numerous bird species. Some of our results highlight the greater importance of urban parks with respect to urban streets as habitats that mitigate the effect of urbanization on birds, a valuable information for sustainable-urban development plans.Fil: Camín, Sergio Ramón. Universidad Nacional de Cuyo. Facultad de Ciencias Exactas y Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Provincia de Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Universidad Nacional de Cuyo. Instituto Argentino de Investigaciones de las Zonas Áridas; ArgentinaFil: Figini, Iara. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Ecología, Genética y Evolución de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Ecología, Genética y Evolución de Buenos Aires; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; ArgentinaFil: Marone, Luis. Universidad Nacional de Cuyo. Facultad de Ciencias Exactas y Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Provincia de Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Universidad Nacional de Cuyo. Instituto Argentino de Investigaciones de las Zonas Áridas; Argentin

Gestation, maternal behaviour, growth and development in the subterranean caviomorph rodent Ctenomys mendocinus (Rodentia, Hystricognathi, Ctenomyidae)

The first information on the gestation period, maternal behaviour, neonatal development and growth of the subterranean caviomorph rodent Ctenomys mendocinus Philippi, 1869, is reported herein. My hypothesis was that, despite its belonging to a typically precocial suborder, the life history traits of C. mendocinus would favour its altricial condition. Th e off spring of C. mendocinus were categorized as altricial by using two diff erent classifi cation systems. Th is condition was also refl ected in maternal care. Females built large nests (2000 cm 3 ) where, after a long gestation period (95.9 days), they gave birth to litters of blind pups, half-naked, with external ear meatus open and good physical coordination. Th e mothers suckled the off spring in long bouts (19.9 min), retrieved their pups, and these showed no tactics to reduce the suckling bout. Overall, evidence was consistent with the hypothesis analyzed, although particularities found, e.g. some precocial traits, suggest the existence in C. mendocinus of a trade-off between the constraints and advantages related to its subterranean way of life and the phylogenetic inertia typical of caviomorphs.Fil: Camín, Sergio Ramón. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Provincia de Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Universidad Nacional de Cuyo. Instituto Argentino de Investigaciones de las Zonas Áridas; Argentin

Seed preferences suggest a high vulnerability of the Yellow Cardinal ( Gubernatrix cristata ) to habitat degradation in Argentina

The Yellow Cardinal is a globally endangered species endemic of southern South America. Knowledge of its general biology has increased in recent years, but its feeding ecology is less well-known. Assessing the feeding ecology of endangered species imposes ethical dilemmas, and we therefore took advantage of Yellow Cardinals rescued by rangers from illegal trafficking in the Monte desert, Mendoza, Argentina, to experimentally assess their seed preferences by using two different seed sets to test the hypotheses that (1) the birds prefer medium-sized and large seeds of native grass species, which are the seeds that are most reduced by cattle grazing, and (2) birds are not able to handle and consume the large seeds typical of non-native crop species. Choice and non-choice experiments were combined to assess the seed preferences. In the experiments with eight native seeds <1 mg (4 grasses, 4 forbs) the birds preferred the medium-sized and large grass seeds over the forb seeds. In the experiment with eight grass seeds (4 native, 4 commercial; 0.23–33 mg) birds had difficulty in handling the heaviest seeds, with a threshold between 7 and 25 mg. This difficulty might explain the positive association of the Yellow Cardinal with wild savannahs and xerophytic shrubland but not with agricultural fields, since common crops have large seeds (40–350 mg). Given the species affinity for habitats that are often used for livestock ranching, overgrazing should be included as a source of habitat degradation due to the reduction in key food resources.Fil: Marone, Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Provincia de Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Universidad Nacional de Cuyo. Instituto Argentino de Investigaciones de las Zonas Áridas; ArgentinaFil: Camín, Sergio Ramón. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Provincia de Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Universidad Nacional de Cuyo. Instituto Argentino de Investigaciones de las Zonas Áridas; Argentin

Context-dependent foraging by seed-eating birds does not necessarily mean low ecological predictability

Flexibility of foraging behaviour affects our capacity to predict ecological outputs such as population responses to habitat change. Some birds forage following rules of absolute value of the food item (i.e., absolute valuation). Their realized diet is strongly correlated with the profitability of the food item and it is predictable. Consumers, however, do not always follow absolute rules. Opportunistic foragers adjust food consumption based on the availability of the food item. Their diet is still predictable but more elusive. Relativistic or context-dependent foragers change the ranks of food preferences depending on the presence of alternative food options in the choice set. Predicting their contingent diet is particularly difficult. We tested if the context of seed availability affects foraging decisions of three seed-eating bird species (the Rufous-collared Sparrow (Zonotrichia capensis (Statius Muller, 1776)), the Many-colored Chaco Finch (Saltatricula multicolor (Burmeister, 1860)), and the Common Diuca Finch (Diuca diuca (Molina, 1782))) using choice experiments aimed at detecting if seed preferences for two types of target seeds changed according to context. Birds showed very similar rankings of preferences for target seeds; however, preferences for attractive food items were not fixed but often increased in less valuable contexts. Although results imply some degree of context-dependent behaviour, predictability of bird diet was preserved because the ranking of preferences remained mostly unchanged between contexts (and among bird species), and the higher consumption of target grass seeds in a less attractive context was widely expected from the intrinsic properties of the seeds.La souplesse du comportement d’approvisionnement a une incidence sur la capacité de prédire des conséquences écologiques telles que les réactions d’une population aux modifications de l’habitat. Certains oiseaux s’approvisionnent en suivant des règles basées sur la valeur absolue de l’aliment. Leur alimentation réelle est fortement corrélée a` la profitabilité de l’aliment et est prévisible. Toutefois, les consommateurs n’observent pas toujours des règles absolues. Les animaux opportunistes ajustent leur consommation de nourriture en fonction de la disponibilité de l’aliment. Leur régime alimentaire demeure prévisible, mais plus difficile a` définir. Les animaux relativistes ou dépendants du contexte changent le classement des aliments qu’ils préfèrent selon la présence d’autres options d’aliments parmi les choix possibles. Il est particulièrement difficile de prédire leur régime alimentaire. Nous avons vérifié si le contexte de disponibilité de graines avait une incidence sur les décisions d’approvisionnement de trois espèces d’oiseaux granivores (le bruant chingolo (Zonotrichia capensis (Statius Muller, 1776)), le saltatricule du chaco (Saltatricula multicolor (Burmeister, 1860)) et le diuca gris (Diuca diuca (Molina, 1782))) avec des expériences de sélection ayant pour but de déterminer si les préférences pour deux types de graines cibles changeaient selon le contexte. Les oiseaux présentaient des classements de préférence des graines cibles très semblables. Cependant, la préférence d’aliments très attrayants n’était pas fixée, augmentant souvent dans des contextes de moins grande valeur. Si les résultats indiquent un certain degré de dépendance du comportement sur le contexte, la prévisibilité du régime alimentaire des oiseaux était conservée parce que le classement des préférences demeurait principalement inchangé d’un contexte a` l’autre (et d’une espèce d’oiseau a` l’autre), et qu’une consommation plus élevée de graines cibles dans un contexte moins attrayant était largement prévisible a` la lumière des propriétés intrinsèques des graines.Fil: Marone, Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Provincia de Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Universidad Nacional de Cuyo. Instituto Argentino de Investigaciones de las Zonas Áridas; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ecología, Genética y Evolución. Grupo de Investigación en Ecología de Comunidades del Desierto; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagóica. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Esquel. Centro de Investigación Esquel de Montaña y Estepa Patagónica; ArgentinaFil: Camín, Sergio Ramón. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Provincia de Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Universidad Nacional de Cuyo. Instituto Argentino de Investigaciones de las Zonas Áridas; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ecología, Genética y Evolución. Grupo de Investigación en Ecología de Comunidades del Desierto; ArgentinaFil: Cueto, Víctor. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Ecología, Genética y Evolución de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Ecología, Genética y Evolución de Buenos Aires; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ecología, Genética y Evolución. Grupo de Investigación en Ecología de Comunidades del Desierto; Argentin

Neophobia and dietary wariness

The excel file includes experimental data used to estimate object neophobia, dietary wariness and consumption, each one in a different tab

Data from: Do neophobia and dietary wariness explain ecological flexibility? An analysis with two seed-eating birds of contrasting habits

The neophobia threshold hypothesis (NTH) suggests that the acquisition and maintenance of a high behavioral and ecological flexibility in the evolutionary and adaptive history of a species is the consequence of lower levels of neophobia towards new micro-habitats and of dietary wariness of novel foods. To test this idea we assessed the degree of neophobia and dietary wariness in two seed-eating bird species with contrasting degrees of ecological flexibility that inhabit the central Monte desert (Argentina): a grass-seed specialist, the many-colored chaco-finch, and a generalist feeder, the rufous-collared sparrow. We expected that both species would exhibit neophobia and wariness when faced with new foraging opportunities but that the rufous-collared sparrow would be less neophobic and less wary than the specialized many-colored chaco-finch. Experimental indicators of neophobia and dietary wariness included willingness to eat near novel objects and willingness to eat novel seeds, respectively. Both species showed similar levels of reluctance to novelty, although the sparrow could be slightly more reluctant than the finch. Contrary to our predictions, the sparrow was neither less hesitant nor faster or greedier than the finch. This experimental evidence does not support a negative relationship between neophobia/wariness and ecological flexibility in these two seed-eating birds and it coincides with the growing evidence that challenges the NTH. Some of our results provide support for the dangerous niche hypothesis, especially as the rufous-collared sparrow, that feeds on more diverse and potentially dangerous food, showed higher levels of neophobia in some cases. Although the idea of neophobia and wariness being plausible causes of ecological specialization sounds attractive, the current situation calls for further research so that the causes of ecological flexibility in granivorous birds can be better understood

Do neophobia and dietary wariness explain ecological flexibility?: An analysis with two seed-eating birds of contrasting habits

The neophobia threshold hypothesis (NTH) suggests that the acquisition and maintenance of a high behavioral and ecological flexibility in the evolutionary and adaptive history of a species is the consequence of lower levels of neophobia towards new micro-habitats and of dietary wariness of novel foods. To test this idea we assessed the degree of neophobia and dietary wariness in two seed-eating bird species with contrasting degrees of ecological flexibility that inhabit the central Monte desert (Argentina): a grass-seed specialist, the many-colored chaco-finch, and a generalist feeder, the rufous-collared sparrow. We expected that both species would exhibit neophobia and wariness whenfaced with new foraging opportunities but that the rufous-collared sparrow would be less neophobic and less wary than the specialized many-colored chaco-finch. Experimental indicators of neophobia and dietary wariness included willingness to eat near novel objects and willingness to eat novel seeds, respectively. Both species showed similar levels of reluctance to novelty, although the sparrow could be slightly more reluctant than the finch. Contrary to our predictions, the sparrow was neither less hesitant nor faster or greedier than the finch. This experimental evidence does not support a negative relationship between neophobia / wariness and ecological flexibility in these two seed eatingbirds and it coincides with the growing evidence that challenges the NTH. Some of our results provide support for the dangerous niche hypothesis, especially as the rufous-collared sparrow, that feeds on more diverse and potentially dangerous food, showed higher levels of neophobia in some cases. Although the idea of neophobia and wariness being plausible causes of ecological specialization sounds attractive, the current situation calls for further research so that the causes of ecological flexibility in granivorous birds can be better understood.Fil: Camín, Sergio Ramón. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Provincia de Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Universidad Nacional de Cuyo. Instituto Argentino de Investigaciones de las Zonas Áridas; ArgentinaFil: Martin Albarracin, Valeria Leticia. Universidad Nacional de Cuyo. Facultad de Ciencias Exactas y Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; ArgentinaFil: Jefferies, María Milagros. Universidad Nacional de Cuyo. Facultad de Ciencias Exactas y Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Marone, Luis. Universidad Nacional de Cuyo. Facultad de Ciencias Exactas y Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Provincia de Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Universidad Nacional de Cuyo. Instituto Argentino de Investigaciones de las Zonas Áridas; Argentin

Exploring food preferences and the limits of feeding flexibility of seed-eating desert birds

Habitat degradation caused by cattle grazing may be a serious threat for seed-eating birds because the availability of beneficial seeds usually diminishes in grazed areas. Ecologically plastic species might, however, circumvent food deprivation via changes in foraging behaviour. We studied the limits of feeding flexibility and factors affecting seed preferences in Zonotrichia capensis, Diuca diuca, and Saltatricula multicolor. We experimentally assessed preferences for seeds of eight grass and eight forb species by using a protocol that combines choice and non-choice trials, and employed a different batch of experiments to evaluate some plausible causes of different feeding flexibility. On average, birds consumed 45–140% more grass than forb seeds, confirming previous results. Z. capensis preferred several grass and forb seeds, and showed maximum feeding flexibility. S. multicolor and, to a lesser extent, D. diuca, were grass specialists that preferred large and medium-sized grass seeds. The size of forb seeds did not affect preferences. Coat thickness of grass seeds did not seriously reduce consumption levels. Birds showed low ability to feed on resources characteristic of degraded environments (i.e. annual grass seeds). Species-specific differences in behavioural flexibility could be used to predict dietary and numerical responses of seed-eating birds to habitat degradation.Fil: Camín, Sergio Ramón. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Provincia de Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Universidad Nacional de Cuyo. Instituto Argentino de Investigaciones de las Zonas Áridas; ArgentinaFil: Cueto, Víctor. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagóica. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Esquel. Centro de Investigación Esquel de Montaña y Estepa Patagónica; ArgentinaFil: Lopez de Casenave, Javier Nestor. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Ecología, Genética y Evolución de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Ecología, Genética y Evolución de Buenos Aires; ArgentinaFil: Marone, Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Provincia de Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Universidad Nacional de Cuyo. Instituto Argentino de Investigaciones de las Zonas Áridas; Argentin

Bird diversity-environment relationships in urban parks and cemeteries of the Neotropics during breeding and non-breeding seasons

Background Urbanization will increase in the next decades, causing the loss of green areas and bird diversity within cities. There is a lack of studies at a continental scale analyzing the relationship between urban green areas, such as parks and cemeteries, and bird species richness in the Neotropical region. Bird diversity-environment relationships in urban parks and cemeteries may be influenced by latitudinal gradients or species-area relationships. However, the seasonal variation of species diversity- environment has not been analyzed at a continental scale in the Neotropics. Methods Bird surveys were conducted in 36 cemeteries and 37 parks within 18 Neotropical cities during non-breeding and breeding seasons. Bird diversity was assessed through Hill numbers, focusing on species richness, the effective number of species derived from Shannon index and the Simpson index. Environmental variables included latitude, altitude, and local scale variables such as area size, habitat diversity and pedestrian traffic. Results Species richness and Shannon diversity were higher during the breeding season, whereas Simpson diversity did not vary between seasons. During both seasons, species richness increased with area size, was negatively related to altitude, and was the highest at 20° latitude. Species richness was also positively related to habitat diversity, pedestrian traffic, and was highest in suburban areas during the non-breeding season. Shannon and Simpson diversity showed significant relationships with habitat diversity and area size during the breeding season. Bird diversity was similar between parks and cemeteries. Discussion Our results showed that urban parks and cemeteries have similar roles in conserving urban bird diversity in Neotropical cities. However, species diversity-environment relations at the continental scale varied between seasons, highlighting the importance of conducting annual studies