Impact of red-bellied squirrels on the bird community of the Pampas Region, Argentina
Ecología Austral, 25:37-45 (2015)The red-bellied tree squirrel Callosciurus erythraeus was introduced in Luján, Argentina, in 1970, where it spread rapidly. Squirrels can affect birds through nest predation, interference and competition for food and nesting sites. We aimed to compare community composition, density and richness of birds in forested areas within and outside the range distribution (680 km2 in 2004) of the main population of these squirrels in the country. We selected seven paired sites (each pair had similar vegetation structure and composition) and other 14 sites, half in each condition (with and without squirrels). In each of these 28 sites, we did 4–5 point counts in each site during spring-summer 2008-2009, recording all bird individuals that were seen/heard <10–20 m from the observer. Species richness was rarefied to the smallest number of point counts per site. Community composition differed among sites with and without squirrels, particularly for paired sites. We found no differences in bird density though species richness was higher for paired sites without squirrels. To assess if squirrels do consume bird eggs and if they have any egg-size preference, we conducted cafeteria experiments offering fruit and three eggs of different sizes to individual squirrels kept in a large cage (3x2x2 m) for < 24 h. Few squirrels (2/25) consumed the eggs. Our results suggest that squirrels could negatively affect some bird species but not through nest predation.
Main Authors: | , , |
---|---|
Format: | Digital revista |
Language: | spa |
Published: |
Asociación Argentina de Ecología
2015
|
Online Access: | https://ojs.ecologiaaustral.com.ar/index.php/Ecologia_Austral/article/view/54 |
Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
id |
rev-ecoaus-article-54 |
---|---|
record_format |
ojs |
institution |
AUSTRAL |
collection |
OJS |
country |
Argentina |
countrycode |
AR |
component |
Revista |
access |
En linea |
databasecode |
rev-ecoaus |
tag |
revista |
region |
America del Sur |
libraryname |
Asociación Argentina de Ecología |
language |
spa |
format |
Digital |
author |
Messetta, María Laura Milesi, Fernando Guichón, María Laura |
spellingShingle |
Messetta, María Laura Milesi, Fernando Guichón, María Laura Impact of red-bellied squirrels on the bird community of the Pampas Region, Argentina |
author_facet |
Messetta, María Laura Milesi, Fernando Guichón, María Laura |
author_sort |
Messetta, María Laura |
title |
Impact of red-bellied squirrels on the bird community of the Pampas Region, Argentina |
title_short |
Impact of red-bellied squirrels on the bird community of the Pampas Region, Argentina |
title_full |
Impact of red-bellied squirrels on the bird community of the Pampas Region, Argentina |
title_fullStr |
Impact of red-bellied squirrels on the bird community of the Pampas Region, Argentina |
title_full_unstemmed |
Impact of red-bellied squirrels on the bird community of the Pampas Region, Argentina |
title_sort |
impact of red-bellied squirrels on the bird community of the pampas region, argentina |
description |
Ecología Austral, 25:37-45 (2015)The red-bellied tree squirrel Callosciurus erythraeus was introduced in Luján, Argentina, in 1970, where it spread rapidly. Squirrels can affect birds through nest predation, interference and competition for food and nesting sites. We aimed to compare community composition, density and richness of birds in forested areas within and outside the range distribution (680 km2 in 2004) of the main population of these squirrels in the country. We selected seven paired sites (each pair had similar vegetation structure and composition) and other 14 sites, half in each condition (with and without squirrels). In each of these 28 sites, we did 4–5 point counts in each site during spring-summer 2008-2009, recording all bird individuals that were seen/heard <10–20 m from the observer. Species richness was rarefied to the smallest number of point counts per site. Community composition differed among sites with and without squirrels, particularly for paired sites. We found no differences in bird density though species richness was higher for paired sites without squirrels. To assess if squirrels do consume bird eggs and if they have any egg-size preference, we conducted cafeteria experiments offering fruit and three eggs of different sizes to individual squirrels kept in a large cage (3x2x2 m) for < 24 h. Few squirrels (2/25) consumed the eggs. Our results suggest that squirrels could negatively affect some bird species but not through nest predation. |
publisher |
Asociación Argentina de Ecología |
publishDate |
2015 |
url |
https://ojs.ecologiaaustral.com.ar/index.php/Ecologia_Austral/article/view/54 |
work_keys_str_mv |
AT messettamarialaura impactofredbelliedsquirrelsonthebirdcommunityofthepampasregionargentina AT milesifernando impactofredbelliedsquirrelsonthebirdcommunityofthepampasregionargentina AT guichonmarialaura impactofredbelliedsquirrelsonthebirdcommunityofthepampasregionargentina AT messettamarialaura impactodelaardilladevientrerojosobrelacomunidaddeavesenlaregionpampeanaargentina AT milesifernando impactodelaardilladevientrerojosobrelacomunidaddeavesenlaregionpampeanaargentina AT guichonmarialaura impactodelaardilladevientrerojosobrelacomunidaddeavesenlaregionpampeanaargentina |
_version_ |
1787233986916909056 |
spelling |
rev-ecoaus-article-542023-11-02T19:34:36Z Impact of red-bellied squirrels on the bird community of the Pampas Region, Argentina Impacto de la ardilla de vientre rojo sobre la comunidad de aves en la Región Pampeana, Argentina Messetta, María Laura Milesi, Fernando Guichón, María Laura Ecología Austral, 25:37-45 (2015)The red-bellied tree squirrel Callosciurus erythraeus was introduced in Luján, Argentina, in 1970, where it spread rapidly. Squirrels can affect birds through nest predation, interference and competition for food and nesting sites. We aimed to compare community composition, density and richness of birds in forested areas within and outside the range distribution (680 km2 in 2004) of the main population of these squirrels in the country. We selected seven paired sites (each pair had similar vegetation structure and composition) and other 14 sites, half in each condition (with and without squirrels). In each of these 28 sites, we did 4–5 point counts in each site during spring-summer 2008-2009, recording all bird individuals that were seen/heard <10–20 m from the observer. Species richness was rarefied to the smallest number of point counts per site. Community composition differed among sites with and without squirrels, particularly for paired sites. We found no differences in bird density though species richness was higher for paired sites without squirrels. To assess if squirrels do consume bird eggs and if they have any egg-size preference, we conducted cafeteria experiments offering fruit and three eggs of different sizes to individual squirrels kept in a large cage (3x2x2 m) for < 24 h. Few squirrels (2/25) consumed the eggs. Our results suggest that squirrels could negatively affect some bird species but not through nest predation. Ecología Austral, 25:37-45 (2015)Las invasiones biológicas son una amenaza para las especies nativas. La ardilla de vientre rojo, Callosciurus erythraeus, fue introducida en Luján (provincia de Buenos Aires, Argentina) en 1970, donde estableció la principal población silvestre del país. Las ardillas podrían afectar a las aves a través de la depredación de nidadas, de la competencia por alimento y sitios para nidificar, o por interferencia. El objetivo fue comparar la composición, densidad y riqueza de especies de aves en sitios arbolados adentro y afuera del área de distribución de ardillas (680 km2 en 2004) en los alrededores de Luján. Se seleccionaron siete pares de sitios (cada par con estructura y composición de la vegetación similar) más otros 14 sitios (sin parear), la mitad en cada condición (con y sin ardillas). En cada uno de los 28 sitios se establecieron 4–5 puntos de conteo de 10-20 m de radio y durante dos días de primavera-verano 2008-2009 se registraron todas las aves vistas/oídas. La composición de las comunidades de aves resultó diferente entre sitios con y sin ardillas, más notoriamente al comparar entre sitios pareados. No se detectaron diferencias en la densidad de aves pero la riqueza de especies fue mayor en los sitios pareados sin ardillas. Se hicieron ensayos de cafetería para evaluar el consumo de huevos por parte de las ardillas y determinar el tamaño de huevo preferido. Ante la oferta de fruta y huevos de tres tamaños, las ardillas que consumieron fruta, solo en 2/25 ensayos consumieron algún huevo. Nuestros resultados sugieren que las ardillas podrían afectar negativamente a algunas especies de aves pero no a través de la depredación de nidadas. Asociación Argentina de Ecología 2015-04-01 info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion Articles Artículos application/pdf https://ojs.ecologiaaustral.com.ar/index.php/Ecologia_Austral/article/view/54 10.25260/EA.15.25.1.0.54 Ecología Austral; Vol. 25 No. 1 (2015): April 2015, Pages 1-86; 37-45 Ecología Austral; Vol. 25 Núm. 1 (2015): April 2015, Pages 1-86; 37-45 1667-782X 0327-5477 spa https://ojs.ecologiaaustral.com.ar/index.php/Ecologia_Austral/article/view/54/53 Derechos de autor 2015 María Laura Messetta, Fernando Milesi, María Laura Guichón https://creativecommons.org/licenses/by/3.0/ |