Hostname: page-component-76d6cb85b7-6jg5l Total loading time: 0 Render date: 2026-07-10T06:08:28.648Z Has data issue: false hasContentIssue false

Trends and population estimate of the threatened Buff-breasted Sandpiper Calidris subruficollis wintering in coastal grasslands of southern Brazil

Published online by Cambridge University Press:  08 May 2023

Fernando A. Faria
Affiliation:
Laboratório de Aves Aquáticas e Tartarugas Marinhas, Instituto de Ciências Biológicas, Universidade Federal do Rio Grande (FURG), Campus Carreiros, 96203-900, Rio Grande, RS, Brazil Programa de Pós-Graduação em Oceanografia Biológica, Instituto de Oceanografia, Universidade Federal do Rio Grande (FURG), Campus Carreiros, 96203-900, Rio Grande, RS, Brazil
Rafael A. Dias
Affiliation:
Departamento de Ecologia, Zoologia e Genética, Instituto de Biologia, Universidade Federal de Pelotas (UFPEL), Campus Universitário Capão do Leão s/nº, CP 354, 96010-900, Pelotas, RS, Brazil
Glayson A. Bencke
Affiliation:
Museu de Ciências Naturais, Secretaria do Meio Ambiente e Infraestrutura (SEMA), 90690-000, Porto Alegre, RS, Brazil
Leandro Bugoni
Affiliation:
Laboratório de Aves Aquáticas e Tartarugas Marinhas, Instituto de Ciências Biológicas, Universidade Federal do Rio Grande (FURG), Campus Carreiros, 96203-900, Rio Grande, RS, Brazil Programa de Pós-Graduação em Oceanografia Biológica, Instituto de Oceanografia, Universidade Federal do Rio Grande (FURG), Campus Carreiros, 96203-900, Rio Grande, RS, Brazil
Nathan R. Senner
Affiliation:
Department of Environmental Conservation, College of Natural Sciences, University of Massachusetts, Amherst, MA, USA
Juliana B. Almeida
Affiliation:
SAVE Brasil – Sociedade para a Conservação das Aves do Brasil, 05427-010, Pinheiros, SP, Brazil Manomet, Inc., 02360, Plymouth, MA, USA
Guilherme Tavares Nunes
Affiliation:
Centro de Estudos Costeiros, Limnológicos e Marinhos (CECLIMAR), Universidade Federal do Rio Grande do Sul (UFRGS), UFRGS Litoral, 95625-000, Imbé, RS, Brazil
Maycon S. S. Gonçalves
Affiliation:
Regional Centre of Water Studies, University of Castilla La Mancha, Albacete, Spain
James E. Lyons
Affiliation:
US Geological Survey, Eastern Ecological Science Center at the Patuxent Research Refuge, Laurel, MD, USA

Summary

Information about population sizes, trends, and habitat use is key for species conservation and management. The Buff-breasted Sandpiper Calidris subruficollis (BBSA) is a long-distance migratory shorebird that breeds in the Arctic and migrates to south-eastern South America, wintering in the grasslands of southern Brazil, Uruguay, and Argentina. Most studies of Nearctic migratory species occur in the Northern Hemisphere, but monitoring these species at non-breeding areas is crucial for conservation during this phase of the annual cycle. Our first objective was to estimate trends of BBSA at four key areas in southern Brazil during the non-breeding season. We surveyed for BBSA and measured vegetation height in most years from 2008/09 to 2019/20. We used hierarchical distance sampling models in which BBSA abundance and density were modelled as a function of vegetation height and corrected for detectability. Next, we used on-the-ground surveys combined with satellite imagery and habitat classification models to estimate BBSA population size in 2019/20 at two major non-breeding areas. We found that abundance and density were negatively affected by increasing vegetation height. Abundance fluctuated five- to eight-fold over the study period, with peaks in the middle of the study (2014/15). We estimated the BBSA wintering population size as 1,201 (95% credible interval [CI]: 637–1,946) birds in Torotama Island and 2,232 (95% CI: 1,199–3,584) in Lagoa do Peixe National Park during the 2019/20 austral summer. Although no pronounced trend was detected, BBSA abundance fluctuated greatly from year to year. Our results demonstrate that only two of the four key areas hold high densities of BBSA and highlight the positive effect of short grass on BBSA numbers. Short-grass coastal habitats used by BBSA are strongly influenced by livestock grazing and climate, and are expected to shrink in size with future development and climatic changes.

Information

Type
Research Article
Copyright
© The Author(s), 2023. Published by Cambridge University Press on behalf of BirdLife International

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

Article purchase

Temporarily unavailable

Supplementary material: File

Faria et al. supplementary material

Tables S1-S2 and Figure S1

Download Faria et al. supplementary material(File)
File 42.8 KB