Chapter 11
Assessing Bird Exclusion Effects
in a Wetland Crossed by a Railway
(Sado Estuary, Portugal)
Carlos Godinho, Luísa Catarino, João T. Marques, António Mira
and Pedro Beja
Abstract Linear transportation infrastructures may displace wildlife from nearby
areas that otherwise would provide adequate habitat conditions. This exclusion
effect has been documented in roads, but much less is known about railways. Here
we evaluated the potential exclusion effect on birds of a railway crossing a wetland
of international importance (Sado Estuary, Portugal). We selected 22 sectors representative of locally available wetland habitats (salt pans, rice paddy fields, and
intertidal mudflats); of each, half were located either close to (0–500 m) or far from
(500–1500 m) the railway line. Water birds were counted in each sector between
December 2012 and October 2015, during two months per season (spring, summer,
winter, and autumn) and year, at both low and high tide. We recorded 46 species, of
which the most abundant (>70% of individuals) were black-headed gull, greater
flamingo, northern shoveler, black-tailed godwit, and lesser black-backed gull. Peak
abundances were found in autumn and winter. There was no significant variation
between sectors close to and far from the railway in species richness, total abundance, and abundance of the most common species. Some species tended to be most
C. Godinho (&) Á L. Catarino
LabOr—Laboratório de Ornitologia, ICAAM—Instituto de Ciências Agrárias e Ambientais
Mediterrânicas, Universidade de Évora, Mitra, 7002-554 Évora, Portugal
e-mail: capg@uevora.pt
J.T. Marques Á A. Mira
Unidade de Biologia da Conservação, Departamento de Biologia, Universidade de Évora,
Mitra, 7002-554 Évora, Portugal
J.T. Marques Á A. Mira
CIBIO/InBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos,
Universidade de Évora, Pólo de Évora, Casa do Cordovil 2º Andar, 7000-890 Évora, Portugal
P. Beja
CIBIO/InBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos,
Universidade do Porto, Campus Agrário de Vairão, Rua Padre Armando Quintas, 4485-661
Vairão, Portugal
P. Beja
CEABN/InBIO, Centro de Ecologia Aplicada “Professor Baeta Neves”, Instituto Superior de
Agronomia, Universidade de Lisboa, Tapada da Ajuda, 1349-017 Lisboa, Portugal
© The Author(s) 2017
L. Borda-de-Água et al. (eds.), Railway Ecology,
DOI 10.1007/978-3-319-57496-7_11
179
Assessing Bird Exclusion Effects
in a Wetland Crossed by a Railway
(Sado Estuary, Portugal)
Carlos Godinho, Luísa Catarino, João T. Marques, António Mira
and Pedro Beja
Abstract Linear transportation infrastructures may displace wildlife from nearby
areas that otherwise would provide adequate habitat conditions. This exclusion
effect has been documented in roads, but much less is known about railways. Here
we evaluated the potential exclusion effect on birds of a railway crossing a wetland
of international importance (Sado Estuary, Portugal). We selected 22 sectors representative of locally available wetland habitats (salt pans, rice paddy fields, and
intertidal mudflats); of each, half were located either close to (0–500 m) or far from
(500–1500 m) the railway line. Water birds were counted in each sector between
December 2012 and October 2015, during two months per season (spring, summer,
winter, and autumn) and year, at both low and high tide. We recorded 46 species, of
which the most abundant (>70% of individuals) were black-headed gull, greater
flamingo, northern shoveler, black-tailed godwit, and lesser black-backed gull. Peak
abundances were found in autumn and winter. There was no significant variation
between sectors close to and far from the railway in species richness, total abundance, and abundance of the most common species. Some species tended to be most
C. Godinho (&) Á L. Catarino
LabOr—Laboratório de Ornitologia, ICAAM—Instituto de Ciências Agrárias e Ambientais
Mediterrânicas, Universidade de Évora, Mitra, 7002-554 Évora, Portugal
e-mail: capg@uevora.pt
J.T. Marques Á A. Mira
Unidade de Biologia da Conservação, Departamento de Biologia, Universidade de Évora,
Mitra, 7002-554 Évora, Portugal
J.T. Marques Á A. Mira
CIBIO/InBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos,
Universidade de Évora, Pólo de Évora, Casa do Cordovil 2º Andar, 7000-890 Évora, Portugal
P. Beja
CIBIO/InBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos,
Universidade do Porto, Campus Agrário de Vairão, Rua Padre Armando Quintas, 4485-661
Vairão, Portugal
P. Beja
CEABN/InBIO, Centro de Ecologia Aplicada “Professor Baeta Neves”, Instituto Superior de
Agronomia, Universidade de Lisboa, Tapada da Ajuda, 1349-017 Lisboa, Portugal
© The Author(s) 2017
L. Borda-de-Água et al. (eds.), Railway Ecology,
DOI 10.1007/978-3-319-57496-7_11
179