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Cases of parasitism of the Shiny Cowbird (Molothrus bonariensis) on the Rufous-collared Sparrow (Zonotrichia capensis) have only been reported in urban areas below 2817 masl in Ecuador. Between January and March 2022, in the city of Quito, Ecuador, at 3040 masl, we registered parasitism by the Shiny Cowbird using the Rufous-collared Sparrow as a host. We observed the fledgling Shiny Cowbird insistently begging to be fed by adult Rufous-collared Sparrows over a period of 58 days, until the fledgling abandoned parental care. This report represents an extension of 223 m in the altitudinal range of parasitism between these two species, and contributes to information on the expansion and colonization of the Shiny Cowbird in high Andean areas. Our record of a longer duration of parental care of the fledgling has implications for the parasite-host relationship, requiring greater energy expenditure by small hosts. [ABSTRACT FROM AUTHOR]

The distribution of resources used by birds directs ecological processes, such as habitat selection. The aim of the present study was to compare in two consecutive winters the habitat selection of grassland sparrows, and to evaluate the influence of annual precipitation and available ground seed biomass. Over two winters we collected seeds from the ground at 45 sites used by Baird's Sparrow (Centronyx bairdii) and Grasshopper Sparrow (Ammodramus savannarum) and at random sites (n = 45) where no birds were registered. We determined used sites by radio-tracking captured birds fitted with a transmitter. Sites used by sparrows had significantly higher seed biomass than random sites, and this was similar between species. Therefore, the food resource plays an important role in the selection of the winter habitat of the sparrows. In addition, we found a positive correlation between annual precipitation and seed biomass, which is important in a climate change scenario, due to the influence we found on the birds to select wintering sites with higher seed biomass in years with less rainfall. Our results expand the available information on the winter habitat selection of C. bairdii and A. savannarum in Mexico. [ABSTRACT FROM AUTHOR]

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Eared doves (Zenaida auriculata) may cause up to 50% of losses in some damaged crops. The objective of this study was to measure a contraceptive bait (nicarbazin pellets 0,5%) acceptance by Eared Doves in individual cages (10 birds/treatments). After quarantine and an adaptation period to the cages, the bait (nicarbazin pellets 0,5%) was offered to the doves for four hours per day for 21 consecutive days in three formulations (treatments) according to the bait: (1) OvoControlS® developed for sparrows; (2) OvoControlS® mixed with cracked corn in a 78:22 ratio; (3) was offered the corresponding bait treatment, cracked OvoControlP® elaborated for rock pigeon (Columba livia). Every morning each bird was offered the bait of the treatment, and in the afternoon a maintenance diet was offered in the same amount and daily consumption was registered. The average consumption/week of OvoControlS® and OvoControlS® with corn was less than 1.0g. Cracked OvoControlP® bait was accepted by birds. The consume increased in weeks 2 and 3 (p<0.05), exceeding 1.0 g average/week and was higher than the other formulations (p<0.05). It can be concluded that this treatment was accepted and consumed by eared doves in captivity in amounts that could cause an effect on this species reproduction. [ABSTRACT FROM AUTHOR]

Copyright of Zeledonia is the property of Asociacion Ornitologica de Costa Rica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Agro Productividad is the property of Colegio de Postgraduados and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)