ABSTRACT
In 2017, one pair of Oriental reed warblers (Acrocephalus orientalis) with color aberrations was found in Yongnianwa National Wetland Park, Hebei, China. The female bird exhibited white feathers on the head, neck, and upper back, and the base of the beak was flesh-red in color. The male had a few feathers on the outer edges of the left and right primary wing coverts that were white, which was determined to be leucism after analysis. The breeding pairs laid their first egg on May 29, with a clutch size of four eggs. After an incubation period of 13 days, two chicks hatched on June 13, 2017. The nest was found empty on June 20 when the chicks were 7 days old and before fledging age; therefore, it was presumed that the chicks had been predated. A white parrot egg was added to the nest during the incubation period to test the egg recognition ability of breeding pairs and was successfully rejected. To the best of our knowledge, this is the first report of color aberrations in the Oriental reed warbler, and we found that this color aberrations did not affect some reproductive and antiparasitic behaviors of the birds, but whether it affects their breeding success needs to be further studied.
ABSTRACT
Se reporta la primera observación de un espécimen leucístico en el Juil de Jamapa, Rhamdia laticauda en el noreste del estado de Oaxaca. En un estudio ictiológico de la Reserva de la Biosfera Tehuacán-Cuicatlán en el río Xiquila de la cuenca alta del río Papaloapan, el pez se capturó con pesca eléctrica y se fotografió. El bagre vivo mostró una reducción de pigmentos en la piel, manchas blancas y ojos negros normales. Esto contribuye al conocimiento de la variabilidad intraespecífica y la historia natural de R. laticauda. Se discuten las causas potenciales de esta anomalía de color.
Here, we report the first observation of a leucistic specimen in the Rock catfish, Rhamdia laticauda in the Northeast of Oaxaca, Mexico. We caught the specimen by electric fishing and then photographed during an ichthyological survey carried out in the Tehuacán-Cuicatlán Biosphere Reserve in the Xiquila River of the upper Papaloapan River basin. The live catfish showed a lack of pigment in the skin, white spots, and normal eye color. This information contributes to the knowledge about intraspecific variability and natural history of R. laticauda. We discuss the potential causes of this color anomaly.
ABSTRACT
The existence of hypopigmentation like leucism is the result of genetic anomalies that might be enhanced by external factors such as pollution. This anomaly may reduce survival rates. Leucism has been recorded in wildlife, but overall, it is considered very rare. There have been few records of mantled howler monkeys with leucism in Mexico and Costa Rica, but whole-body leucism in howler monkeys from South America was unknown. In this article, we report for the first-time documented cases of whole-body leucism in young individuals of mantled howler monkeys Alouatta palliata in an isolated remanent of tropical dry forest in southwestern Ecuador known as Cerro Blanco Protective Forest. In total, we found two juvenile individuals with leucism in October 2021. The report of howler monkeys with whole-body leucism may be caused by two processes: inbreeding because of isolated populations, environmental pressure caused by pollution, or the interaction of both. Our findings also reveal that hypopigmentation is becoming more frequent in howler monkey populations along its distributional range. Therefore, it is important to promote research in this field to disentangle the causes of hypopigmentation and to consider a regional management strategy for the species.
La existencia de afecciones que causan hipopigmentación, como el leucismo, son el resultado de anomalías genéticas que pueden verse potenciadas por factores externos como la contaminación. Estas anomalías puedes reducir las tasas de supervivencia. Se ha registrado leucismo en la vida silvestre, pero en general, se considera muy raro. En México y Costa Rica se ha reportado la existencia de casos aislados de monos aulladores de manto con leucismo, pero se desconocía el leucismo de cuerpo completo en monos aulladores para América del Sur. En este artículo, reportamos por primera vez casos documentados de leucismo en todo el cuerpo en individuos juveniles de monos aulladores de manto Alouatta palliata en un remanente aislado de bosque seco tropical en el suroeste de Ecuador conocido como Bosque Protector Cerro Blanco. En total, encontramos dos individuos juveniles con leucismo en octubre de 2021. Este reporte de monos aulladores con leucismo en todo el cuerpo puede ser causado por dos procesos: apareamiento dentro de individuos de la misma población causado por el aislamiento, la presión ambiental causada por la contaminación o la interacción de ambos. Nuestros hallazgos también revelan que la hipopigmentación es cada vez más frecuente en las poblaciones de monos aulladores a lo largo de su rango de distribución. Por lo tanto, es importante promover la investigación en este campo para determinar las causas de la hipopigmentación y considerar una estrategia de manejo regional para la especie. Palabras clave: aberraciones cromáticas, pérdida de conectividad, anomalías genéticas, endogamia, cambio de pigmentación en primates por contaminación, Bosque Seco del Pacífico Ecuatorial.
