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Breeding biology and behavior of the Collared Forest-Falcon (Micrastur semitorquatus) in Guatemala
... Collared Forest-Falcons, Crane Hawks, Gray Hawks, and Roadside Hawks are four of the most abundant resident raptor species in the tropical dry forest along the coast of Jalisco (Martínez-Ruiz et al. 2020). These four focal species include a range of body size and varying ecological requirements (Brown and Amadon 1968, Johnsgard 1990, Panasci 2012, Sutter 2012, Thorstrom 2012, Bibles et al. 2020. Collared Forest-Falcons (560-940 g) and Crane Hawks (495 g) are medium-sized raptors (Brown and Amadon 1968) of the forest interior , Sutter et al. 2001, Thorstrom 2012. ...
... These four focal species include a range of body size and varying ecological requirements (Brown and Amadon 1968, Johnsgard 1990, Panasci 2012, Sutter 2012, Thorstrom 2012, Bibles et al. 2020. Collared Forest-Falcons (560-940 g) and Crane Hawks (495 g) are medium-sized raptors (Brown and Amadon 1968) of the forest interior , Sutter et al. 2001, Thorstrom 2012. Collared Forest Falcons nest in tree cavities and hunt from a perch in dense vegetation (Thorstrom 2012), while Crane Hawks build nests in the forest canopy and employ a distinctive search-andprobe hunting technique seeking prey in tree hollows, epiphytes, and behind bark (Sutton 1954, Jehl 1968, Sutter et al. 2001. ...
... This corresponds with studies in temperate zones that report greater territorial response of raptors towards conspecifics during the breeding season (Jamieson and Seymour 1983, García and Arroyo 2002, Krüger 2002, Katzner et al. 2003. Our study was conducted during the months of February to March at the start of the nesting season for the Collared Forest-Falcon and the Crane Hawk, which have been reported to commence egg-laying in February or March , Sutter 2012, Thorstrom 2012). There- fore, conspecifics may represent competition for nest-sites, food resources, or mates at the start of the breeding season (Bergo 1987, Garcia and Arroyo 2002, Margalida and Bertran 2005. ...
Little is known of intra- and inter-specific territoriality in Neotropi- cal raptors that may defend territories throughout the year, and face greater inter-specific competition for resources. We evaluated intra- and inter-specific territorial responses of four species of Neotropi- cal raptors in the tropical dry forest of the Chamela-Cuixmala Bio- sphere Reserve, Mexico. We conducted broadcast calls in territories of the Collared Forest-Falcon (Micrastur semitorquatus), Crane Hawk (Geranospiza caerulescens), Gray Hawk (Buteo plagiatus), and Roadside Hawk (Rupornis magnirostris), and measured the la- tency, duration, and type of territorial response to broadcast calls of conspecifics and sympatric raptor species. We applied repeated measures analysis to determine differences in intra- and inter-specif- ic territorial responses of raptors, and GLMMs to evaluate whether traits of body size, nest type, and hunting technique were associated with territorial response by focal raptors. Large-bodied focal raptor species showed high intra-specific territoriality, giving faster, pro- longed responses of various types, including duets and combined responses, to broadcast calls of conspecifics compared to sympat- ric species. All focal raptors showed some inter-specific territori- al response, but this was mainly as vocalizations or displacements towards sympatric species broadcast calls. Species traits of body size, nest type, and hunting technique were associated with latency and duration of territorial response by the larger raptor species that nest in the forest canopy. These traits may be more strongly asso- ciated with territorial response of forest raptors that defend limited resources in a structurally complex environment.
... Micrastur semitorquatus considerada como especie secundaria en el uso de cavidades-nidos (Waters et al., 1990), se ha registrado empleando nidos usados previamente notas científicas por otras especies como Ara ambiguus y Coragyps atratus (Thorstrom y Morales, 1993;Thorstrom et al., 2000). También se ha reportado no solo la utilización del nido sino el acoso a una pareja de Ara ambiguus en Ecuador, consumando el despojo con la expulsión física del pollo que habitaba dentro del nido (López-Lanus, 2000). ...
... Son escasos los estudios que se han llevado a cabo sobre la biología reproductiva de M. semitorquatus. Mader (1979) registra el primer nido en Venezuela, mientras que los estudios de Thorstrom (1990) y Thorstrom et al. (2000), proveen un panorama más completo acerca de su reproducción, comportamiento, vocalizaciones, nidos y huevos. En México, el primer antecedente que se conoce sobre la reproducción de esta especie es el de Cobb (1990), quien describió un nido en la Península de Yucatán, mientras que el primer reporte que se tiene sobre la especie en el área de estudio es de Phillips y Schaldach (1959) en una localidad cercana a Tomatlán, Jalisco. ...
... El nido fue encontrado a mediados de la temporada seca y dado que los huevos tardan aproximadamente de 46 a 48 días en eclosionar , presumiblemente estos iban a eclosionar al inicio de la temporada de lluvias, lo que concuerda con lo descrito en Guatemala (Thorstrom et al., 2000). El sustrato hallado estaba compuesto por trozos finos de madera del mismo árbol, lo que concuerda con lo descrito tanto por Mader (1979) como por Thorstrom et al. (1990Thorstrom et al. ( , 2000. Las presas potenciales reportadas para M. semitorquatus en Guatemala son principalmente mamíferos, aves y reptiles, además de algunos escarabajos , en este caso se hallaron restos de aves (Ortalis sp.), de reptiles (Ctenosaura sp.) y de algunos insectos no identificados. ...
Se analizan aspectos ecológicos de Ruppia maritima L. (Ruppiaceae) en Laguna Larga, localizada en la costa
norte y central de Cayo Coco en Cuba. La laguna fue subdividida de acuerdo con su comportamiento hidrodinámico en
zonas: este, central y oeste. Se evalúo la influencia de diferentes variables ambientales sobre el crecimiento y distribución
de la planta. Se consideraron variables bióticas y abióticas. La macrófita forma parches en la zona este, mientras que en
la parte central y oeste es escasa y dispersa. La biomasa media general de 91.4 g/m2, estuvo influenciada por factores que
limitan el crecimiento de la angiosperma. Las elevadas salinidades y las altas concentraciones de amonio en la columna de
agua fueron “estresores” ambientales comunes en toda la laguna, mientras que la temperatura y la escasez de luz lo fueron
solamente para la zona central y oeste, respectivamente. Por otro lado, el crecimiento de algas filamentosas flotantes y de
epífitas, principalmente del género Cladophora Kützing, contribuyeron a la baja biomasa registrada, debido a la reducción
de luz por efecto de sombreado.
... The species inhabits a wide range of tropical forest habitats, including primary to secondary lowland rainforests, semi-deciduous and deciduous forests (Sick 1997). Its breeding biology is well known compared to other species of Micrastur (Thorstrom et al. 2000). Several studies, from Guatemala and Brazil, suggest the species prefers to nest in cavities, lays 1-3 eggs, which are incubated 46-48 days, and feeds the nestlings until they can fly and feed themselves (Thorstrom et al. 2000, Carrara et al. 2007). ...
... Its breeding biology is well known compared to other species of Micrastur (Thorstrom et al. 2000). Several studies, from Guatemala and Brazil, suggest the species prefers to nest in cavities, lays 1-3 eggs, which are incubated 46-48 days, and feeds the nestlings until they can fly and feed themselves (Thorstrom et al. 2000, Carrara et al. 2007). The breeding season varies geographically: February-August in the humid forests of Guatemala (Thorstrom 2000), August-November in the Brazilian Pantanal (Carrara et al. 2007) and the late spring and austral summer in the Atlantic Forest of southern Brazil (Carvalho-Filho et al. 1998, Vallejos et al. 2008, Marreis et al. 2010, Viana et al. 2010. ...
... Several studies, from Guatemala and Brazil, suggest the species prefers to nest in cavities, lays 1-3 eggs, which are incubated 46-48 days, and feeds the nestlings until they can fly and feed themselves (Thorstrom et al. 2000, Carrara et al. 2007). The breeding season varies geographically: February-August in the humid forests of Guatemala (Thorstrom 2000), August-November in the Brazilian Pantanal (Carrara et al. 2007) and the late spring and austral summer in the Atlantic Forest of southern Brazil (Carvalho-Filho et al. 1998, Vallejos et al. 2008, Marreis et al. 2010, Viana et al. 2010. Although the species typically nests within natural cavities in forests, three records of breeding in man-made structures have been reported in Brazil, where nests with eggs were found in an abandoned building (Carvalho-Filho et al. 1998), a barbecue pit (Marreis et al. 2010) and a house under construction (Viana et al. 2010). ...
Collared Forest Falcon Micrastur semitorquatus ranges from northern Mexico to southern Brazil. This species is known to lay 1–3 eggs. We describe the first four-egg clutch for M. semitorquatus from observations made in southern Brazil, in the state of Santa Catarina. We also describe the nest site, nestling diet and assess sex ratio and mass gain of the nestlings.
... Elevation ranges from 215 to 275 m asl. Climate is warm sub-humid with rains in summer (Aw" 0 (w)(i')g, according to Soto and García (1989). The native vegetation was TDF, but currently, it only remains in fragments covering less than 7% of its original distribution in the area (Williams-Linera and Lorea 2009). ...
... This study shows that despite recurrent human disturbances, the agricultural landscape of this tropical region supports a high bird species richness and diversity, including threatened species such as Doricha eliza, Micrastur semitorquatus, Amazona autumnalis, Amazona oratrix, Pionus senilis, and Trogon melanocephalus. The presence of these uncommon and specialist species (Thorstrom et al. 2000;Ortiz-Pulido et al. 2002;Monterrubio-Rico et al. 2014) in the study area, could suggest that the potentially required vegetation area, habitat coverage and resources remain despite the anthropogenic modifications. Particularly based on the fact that many species are known to be area-sensitive in their habitat requirements and will not use habitat patches unless they exceed a certain minimum size . ...
Tropical ecosystems have undergone severe changes due to human activities such as land-use change for agriculture. However, in agricultural landscapes with remnants of native vegetation, high bird diversity may persist. Here we evaluated bird species richness, diversity, and composition in four landscape units with different matrices: cattle pastures, cornfields, mixed mosaics, and continuous forest. Using nets and direct observations, we recorded 138 bird species. We expected species richness to have a negative relationship with agricultural coverage, thus decreasing in the following sequence of landscape matrices: forest > mixed > corn > pasture. On the contrary, standardized species richness decreased from 122 to 93 species in the following sequence: pasture > mixed > forest > corn. Using a PERMANOVA, we detected significant changes in species composition among landscape units. These differences were represented in a NMDS plot and a Venn Diagram. Species diversity (Hill Numbers) also changed seasonally, and the forest unit had low richness but the highest evenness. This complex landscape allowed the presence of diverse species under risk categories. We conclude that despite recurrent human disturbances in this tropical region, the agricultural landscape, mixed with remnants of natural vegetation, allows the maintenance of highly diverse bird communities, probably due to spatial dynamics among landscape elements.
... In tropical and subtropical forests, many cavity nesting species select large, high cavities, which tend to occur in large old trees (Olah et al. 2014 (Thorstrom et al. 1990, Thorstrom et al. 2000b, Thorstrom 2001, Bonaparte and Cockle 2017. Collared Forest-Falcons in Guatemala and Venezuela nested in cavities 12-24 m high, 23-100 cm in vertical depth, 60 cm in horizontal depth, and with entrance diameters of 16-60 cm (Mader 1979, Thorstrom et al. 1990, 2000aThorstrom 2001 Owl (Pulsatrix perspicillata, 908 g), and Crested Owl (Lophostrix cristata, 620 g), potential nest cavities remain very rare or absent in secondary forest. The barriers related to scarcity and small size of cavities in secondary forest could be studied and partly overcome through nest-box programs that might help bridge the approximately 18-year gap between pasture abandonment and cavity development in protected secondary forest. ...
Passive restoration of secondary forests can partially offset loss of biodiversity following tropical deforestation. Tree cavities, an essential resource for cavity-nesting birds, are usually associated with old forest. We investigated the restoration time for tree cavities suitable for cavity-nesting birds in secondary forest at the Biological Dynamics of Forest Fragments Project (BDFFP) in central Amazonian Brazil. We hypothesized that cavity abundance would increase with forest age, but more rapidly in areas exposed to cutting only, compared to areas where forest was cut and burned. We also hypothesized that cavities would be lower, smaller, and less variable in secondary forest than in old-growth forest, which at the BDFFP is part of a vast lowland forest with no recent history of human disturbance. We used pole-mounted cameras and tree-climbing to survey cavities in 39 plots (each 200 × 40 m) across old-growth forests and 11–34-year-old secondary forests. We used generalized linear models to examine how cavity supply was related to forest age and land-use history (cut only vs cut-and-burn), and principal components analysis to compare cavity characteristics between old-growth and secondary forest. Cavity availability increased with secondary forest age, regardless of land-use history, but the oldest secondary forest (31–34 yr) still had fewer cavities (mean ± SE = 9.8 ± 2.2 cavities ha–1) than old-growth forest (20.5 ± 4.2 cavities ha–1). Moreover, secondary forests lacked cavities that were high and deep, with large entrances—characteristics likely to be important for many species of cavity-nesting birds. Several decades may be necessary to restore cavity supply in secondary Amazonian forests, especially for the largest birds (e.g., forest-falcons and parrots > 190 g). Retention of legacy trees as forest is cleared might help maintain a supply of cavities that could allow earlier recolonization by some species of cavity-nesting birds when cleared areas are abandoned. A Portuguese version of this article is available in Supplementary Material 1.
... B. magnirostris generalmente es abundante en áreas perturbadas (Thiollay, 1989), pero durante la temporada secas presentó abundancias reducidas y también se considerada rara para la Reserva (Domínguez et al., 1996). Buteo brachyurus sólo se registró en puntos elevados en la zona de amortiguamiento, en bordes de selva y en claros parciales y M. semitorquatus presentó Cuadro 2. Parámetros de diversidad de aves rapaces diurnas en la Reserva de la Biosfera Selva el Ocote, Chiapas pocos registros en ambas zonas y aunque tiene una amplia distribución, muestra poblaciones con limitado número de individuos a través de su rango de distribución (Thorstrom et al., 2000). Buteogallus anthracinus también presentó bajas abundancias, a pesar de que es común en el cañón del río La Venta (El Encajonado) (Fig. 1) (obs. ...
LA PÉRDIDA Y DEGRADACIÓN DE AMBIENTES NATURALES ESTÁ AFECTANDO A GRUPOS FUNCIONALES DE GRAN RELEVANCIA, COMO LAS AVES RAPACES DIURNAS. EN ESTE ESTUDIO EVALUAMOS LA VARIACIÓN ESPACIAL DE LA DIVERSIDAD DE ESTE GRUPO EN LA ZONA NÚCLEO Y DE AMORTIGUAMIENTO DE LA RESERVA DE LA BIOSFERA SELVA EL OCOTE, POR MEDIO DE PUNTOS DE CONTEO EN TRANSECTOS Y PUNTOS ELEVADOS. REGISTRAMOS UN TOTAL DE 16 ESPECIES DE AVES RAPACES DIURNAS, DE LAS CUALES 10 SE ENCONTRARON EN LA ZONA NÚCLEO, 14 EN LA ZONA DE AMORTIGUAMIENTO, Y 8 EN AMBAS. CHONDROHIERAX UNCINATUS Y BUTEOGALLUS ANTHRACINUS FUERON EXCLUSIVAS DE LA ZONA NÚCLEO, Y 6 ESPECIES DE LA ZONA DE AMORTIGUAMIENTO. LAS MÁS ABUNDANTES FUERON CATHARTES AURA Y CORAGYPS ATRATUS, EN PUNTOS ELEVADOS EN LA ZONA NÚCLEO, MIENTRAS QUE MICRASTUR RUFICOLLIS LO FUE EN PUNTOS DE CONTEO EN LA ZONA DE AMORTIGUAMIENTO. AUNQUE EN LA ZONA NÚCLEO SE PRESENTÓ MENOR NÚMERO DE ESPECIES, LAS ESTIMACIONES DE DIVERSIDAD Y EQUITATIVIDAD FUERON MAYORES QUE EN LA DE AMORTIGUAMIENTO. LAS ALTAS TASAS DE DEFORESTACIÓN SERÁN DETERMINANTES EN LA DISTRIBUCIÓN Y DIVERSIDAD DE LAS AVES RAPACES DIURNAS DE SELVA EN LA REGIÓN.
... More than half (54%) of the nesting attempts produced at least one fledgling, which was similar to that of cavity-nesting Collared Forest-Falcons (Micrastur semitorquatus; Thorstrom et al. 2000) and Laughing Falcons (Herpetotheres cachinnans; Parker 1997) at Tikal. The most vulnerable stages of reproduction, incubation and brood rearing, accounted for 91% of nesting failures. ...
... Nest predation is the main cause of bird nest failure in the Neotropics (e.g., Peris & Aramburú 1995, Thorstrom et al. 2000, Manica & Marini 2012, Davanço et al. 2013, where most of the nest predator species are birds (Menezes & Marini 2017). However, because nest predation events are rarely witnessed (e.g., França et al. 2009a, Batisteli 2016, Batisteli & Sarmento 2016, predator identity and attack behaviors are frequently unknown. ...
Toucans (Ramphastidae) are primarily frugivorous birds that occasionally prey on eggs and nestlings of other birds, often Passeriformes. Here, we report predation events by the Toco Toucan (Ramphastos toco) on eggs and nestlings of the Buff-necked Ibis (Theristicus caudatus) at the “Buraco das Araras” ecological reserve, Mato Grosso do Sul, central Brazil. At least three of six ibis nests monitored between October 2016 and January 2017 were depredated by the Toco Toucan. In one nest, the single egg was carried to a nearby perch, where the embryo was swallowed completely. In two other nests, the nestlings were 10-15 days old when are depredated. The toucan killed the nestlings by grabbing the head with the beak and shaking vigorously, probably attempting to break the neck. During the attack, the nestlings tried to defend themselves by snapping their bills at the toucan. Once a nestling stopped reacting (dead or dying), the toucan fed on pieces of flesh from the neck. To our knowledge, these are the largest eggs and the heaviest birds preyed upon by toucans.
The Collared Forest-falcon (Micrastur semitorquatus) is distributed from southern Mexico to northern Argentina. This species nests in tree and rock cavities, although the nests have also been observed in human constructions. Here, we report the second nesting record of this species in an archaeological site in southeastern Mexico and provide descriptive data on the nest and nestlings.
El halcón selvático de collar (Micrastur semitorquatus) es el miembro más grande de su
género. Se encuentra en una amplia variedad de hábitats desde el centro de México
hasta el sur de Brasil. En el año 2021 se localizó un nido de M. semitorquatus dentro
de una de las estructuras que conforman el complejo arqueológico de Xkipché, en el
estado de Campeche, México, lo que sería el primer registro en esta región. El mismo
se encontraba a nivel del suelo y en su interior se observaron restos de una iguana
negra (Ctenosaura similis), plumas de la chara yucateca (Cyanocorax yucatanicus) y del
momoto cejas azules (Eumomota superciliosa). Se cree que la anidación de esta especie
en construcciones humanas es un comportamiento adaptativo debido a la pérdida de
hábitat, aunque también puede ser por la flexibilidad de la especie. La información
aquí presentada da pauta para futuros estudios en la zona, teniendo en cuenta que
la fragmentación y la pérdida de hábitat a causa de la actividad de las personas, que
condicionan la supervivencia de esta y otras especies.
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