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Las vocalizaciones de las aves son sin lugar a dudas extraordinarias y cautivantes, adonde quiera que estemos las podremos escuchar. Estos vertebrados, han logrado uno de los sistemas más complejos de comunicación acústica, dado que tienen la capacidad de emitir o producir una gran variedad de sonidos vocales (llamadas, reclamos cantos complejos) y no vocales, también llamados sonidos mecánicos (señales acústicas producidas mediante los picos, y plumas de las alas y la cola).
Las vocalizaciones en las aves son básicamente de dos tipos: cantos y llamados. Los cantos son estructuralmente complejos y generalmente se relacionan con cortejo y territorialidad. Los llamados o reclamos son de estructura acústica más simple y de corta duración, y se relacionan con la conducta de alarma, búsqueda y solicitud de alimento, cohesión de bandadas, entre otros. Estas vocalizaciones son producidas en una estructura llamada siringe u órgano vocal, el cual se ubica en el punto de unión entre la tráquea y donde se bifurcan los bronquios. Esta estructura está asociada al sistema respiratorio y su funcionamiento se da gracias al paso del flujo de aire de manera similar al de la laringe y las cuerdas vocales en los mamíferos.
A nivel mundial, la avifauna está compuesta por alrededor de 9300 especies y en México se estima que tenemos alrededor de 1100 especies, sin embargo, no de todas se conoce su repertorio vocal.
Adicional a la observación directa o visual de las aves, también podemos conocerlas a través del disfrute de su variado y espectacular repertorio vocal, el cual emiten casi durante todo el año, pero con más notoriedad durante la época reproductiva.
En esta sección, RoyalFlycatcher te ofrece un espacio para conocer las aves de diferentes partes del mundo, principalmente de Mexico, y a través de sus vocalizaciones.
Vamos a comenzar por el registro de las aves de uno de los mejores lugares a nivel mundial para la observación visual y contemplación auditiva, no solo por las especies de aves que habitan ahí, sino porque tiene uno de los ecosistemas más importantes del mundo, el Bosque Mesofilo de Montaña. Si señores, estamos hablando de la Reserva de la Biosfera el Triunfo, Chiapas, México.
Alberto Martínez Fernández
royalflycatcher.birding@gmail.com
96 7142 9969
Biologist, ornithologist, certified guide, specialist in birdwatching and nature photography and video. His passion for birds started at an early age; now with more than 20 years of experience. He has collaborated with national and international agencies for bird conservation.
Fernando Gonzales
Oreophasis1844@gmail.com
+52 1 228 151 0507
Biólogo, ornitólogo. Actualmente labora en el Instituto de Ecología, A.C., y se encuentra asociado a la Red Biología y Conservación de Vertebrados. Su interés por las aves inició a muy temprana edad. Tiene mucho interés en la ecología conservación de las aves con especial énfasis en miembros de la familia Cracidae (chachalacas, pavas, pajüiles, hocofaisanes) y específicamente con el pavón Oreophasis derbianus y en otras especies amenazadas. La grabación de señales acústicas emitidas por diversos vertebrados es una de sus pasiones, principalmente las vocalizaciones de las aves neotropicales. Es fundador de la primera Biblioteca de Sonidos de las Aves de México (BISAM)
It is considered as a subspecies of Accipiter striatus. However, its features make it for many a different species; only juveniles could be confused with A. striatus. Because it is not considered a different species, for the IUCN it does not have any risk category. However, its distribution is restricted to southern Mexico, Guatemala, El Salvador, Nicaragua and it is only found in cold forests.
On one of our walks in 2016 outside San Cristóbal de las Casas, we found the first White-breasted Hawk nest in a pine-oak forest. This first nest, built in a pine tree with a height of 25 to 28 meters, was monitored for over a month. We were able to witness the chickens grow and see how the parents brought them food. During this year, the couple had 3 chickens (one female and two males). In the current year 2020, 50 meters from the nest monitored in 2016, in a pine tree with a height similar to the first tree, we were able to see the growth of 4 chickens in a nest. For some reason, a chicken was larger than the rest of them. It is deducted that this individual was from a first laying and the other 3 chickens were at least two weeks old.
Like most accipiter, the parents were within a radius not bigger than 100 meters, to deliver food from male to female. The latter is the one who transports the food to the nest and begins to feed the baby birds chicks.
White breasted Hawk (Accipiter chionogaster) Kaup, 1852.
This is typical of cold lands, common in mixed pine-oak forests and pine forests of the city of San Cristobal de las Casas, Chiapas, and similar locations. At times you can see it going down the ground looking for earthworms and other insects. It is usually in the upper-mid stratum.
During our field work, we watched it nesting 4 meters high on a bromeliad, on a cypress branch. A fairly appropriate site away from potential predators. On the San Cristobalito hill, as this place is known, the vegetation is dominated by pine trees and shrubs with fruits. In most cases, the female was seen carrying fruit to feed the baby birds chicks, within a radius of no more than 50 meters. The male rarely came with food. However, he kept himself on a perch vocalizing when the female approached the nest.
Mirlo de Collar. Rufous-collared Robin (Turdus rufitorques) Hartlaub, 1844 LC: Least Concert
In the nesting season, it is very important to keep in mind that many species of birds may be nesting in the ground; as is the case with the Rufous-browed Wren; a small, fairly short-tailed wren from highland forests, forest edges, and brushes.
On a dirt road in the oak-pine forest within the Montetik park, located on the edge of San Cristobal de las Casas, we found the nest of this wren built in a cavity made in a wall of soil without vegetation, 20 cm high of the dirt road. During filming, the couple was observed carrying food for the chickens. When the parents approached the nest, they made a vocalization and from the nest the chirping of the chickens was heard at the same time. The foraging area was not more than 10 meters into the forest. The time between each visit to the nest was 2-3 minutes on average, bringing a total of 9 different types of (food) insects in a span of 2 hours. It is intuited that the chickens were between the first and second week of growth.
Rufous-browed Wren · (Troglodytes rufociliatus) · Sharpe, 1882. LC: Least Concert
It is a species of owl that lives in the cold forests of Mexico and Guatemala. In Mexico, it is only found in Chiapas. Populations of this species are seriously threatened by accelerated habitat loss.
There are two morphs (color variations in plumage). The gray variation, the most common to find, is presented in the film. The other variation is reddish. At night, when they are vocalizing, it is not easy to find them. The volume during their vocalizing increases at the beginning, and falls abruptly at the end. That causes one to lose the sense of direction where the sound comes from. However, many of the times, when found, they tend to hang for a while; they are territorial. The images presented in the video are from four sites around San Cristobal de las Casas: oak and pine-oak forests, and oak regeneration areas on the roadside. About their nest, we have found that they build it in tree cavities, but its documentation has not been successful.
Bearded Screech Owl (Megascops barbarus) Sclater, PL & Salvin, 1868) VU: vulnerable
