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The Golden Eagle (Aquila chrysaetos) is listed as threatened in Mexico but there is little information on populations in the state of Sonora. We amalgamated 121 records of the Golden Eagle in Sonora between 1892 and 2019, including 49 observations by the authors between 1997 and 2016. Observations were from all months of the year, peaked during the breeding season and again in December with 53.7% representing likely breeding individuals. Most observations were from the Sky Islands region and Sonoran Desert of northern Sonora, with fewer from coastal west-central and especially southern Sonora. Most observations were from grasslands (34.3%), Madrean evergreen woodland (31.3%), and desert-scrub (30.3%), and very few were from subtropical forest and thorn-scrub (≤ 2.0%) suggesting preference for open vegetation communities that foster hunting. We found evidence of recent occupation of all general portions of Sonora that were occupied historically, except in central Sonora due possibly to changes in land use and land cover. Although our results suggest broad-scale distribution has been largely stable, more focused monitoring is needed to understand population trends. Large-scale urban and agricultural development, loss of grasslands and other open environments, electrocution, and poisoning pose major threats to Golden Eagles in Sonora.

The current distribution status, abundance and nesting of the Golden Eagle in Northwestern Baja California, Mexico, based on samplings during 2 years (January 2013–December 2014) throughout a series of scanned transects of 100 km that resulted in a total of 1634 km in length is documented. The average number of individuals detected/100 km was statistically similar between 2013 and 2014, with an average value of 1.5 ± 0.6 during both years. Number of eaglets per nest showed to be statistically independent (p > 0.05) from the abundance of potential prey, altitude, types of vegetation and lineal distance to urban zones. One hundred and one individuals of the Golden Eagle that have been historical (1843–1995) or recently recorded (2000–2014) for 11 localities of Baja California (3 historical and 9 recent) were reported. Five priority areas were identified for habitat conservation of this species in Baja California (Tecate, Valle de Guadalupe, Sierra de Juarez, Valle de Santo Domingo, and Sierra de San Pedro Martir). Chronologically, the population of the Golden Eagle in Baja California has maintained active its distribution and nesting areas at least during the last 2 decades.

ResumenDocumentamos diversos registros recientes de la paloma de collar Streptopelia decaocto, especie exótica, invasora en diversos ranchos, pueblos y ciudades de la península de Baja California. Nuestro primer registro de la especie en Baja California Sur (BCS) lo tuvimos en el otoño de 2008, y a partir de entonces registramos un incremento de la presencia de esta especie en 64% de las localidades (N= 100). Presentamos los primeros 2 registros de anidación de la especie en BCS, con lo que confirmamos el establecimiento de la especie en el estado, con su expansión a otras localidades del sur de la península. Discutimos y proponemos algunas variables que han ayudado a su colonización.AbstractWe report the presence of Eurasian collared-dove Streptopelia decaocto in many towns, villages and ranches of Baja California Peninsula. Our first record was in fall 2008 and since then, we have found an increase in number and distribution of this dove in several locations of the peninsula, with presence in 64% of the total human settlements we surveyed throughout the peninsula (N= 100). We also present information on the first 2 active nests in Baja California Sur. Eurasian collared-dove is breeding in the Baja California Peninsula at the present and is increasing its distribution into the peninsula tightly linked to human altered habitats.

ResumenSe presenta información sobre presas consumidas por la culebra de agua Thamnophis hammondii en un arroyo de montaña en Baja California Sur, México. Esta culebra incluye en su dieta a la rana arborícola de Baja California Pseudacris hypochondriaca curta (especie nativa), pero también a un pez exótico: la tilapia de vientre rojo Tilapia sp. cf. zilli. Este pez introducido en los oasis de Baja California Sur ha desplazado a las especies de peces nativos, y a la vez se ha convertido en un recurso alimentario importante para T. hammondii.AbstractInformation is presented about the prey consumed by the two-stripped garter snake Thamnophis hammondii in a mountain oasis in Baja California Sur, Mexico. The diet of this threatened snake includes the Baja California treefrog Pseudacris hypochondriaca curta (native species), as well as an exotic fish: the red bellied tilapia Tilapia sp. cf. zilli. This exotic species has become invasive in Baja California Sur oases, displacing native fishes and becoming an important dietary resource to T. hammondii.