TY - JOUR
T1 - Stable isotope evidence for trophic overlap of sympatric Mexican Lake Chapala silversides (Teleostei: Atherinopsidae: Chirostoma spp.)
AU - Mercado-Silva, Norman
AU - Lyons, John
AU - Moncayo-Estrada, Rodrigo
AU - Gesundheit, Pablo
AU - Krabbenhoft, Trevor J.
AU - Powell, Daniel L.
AU - Piller, Kyle R.
N1 - Publisher Copyright:
© 2015 Sociedade Brasileira de Ictiologia.
PY - 2015/7/25
Y1 - 2015/7/25
N2 - We explore the trophic role that a diverse sympatric group of fishes in the genus Chirostoma play in a large, shallow lake in central Mexico, Lake Chapala. We use δ13C and δ15N stable isotope – based food web analyses to explore how they relate to other components of the Lake Chapala ecosystem. We find five Chirostoma species in top trophic levels of the Chapala food web compared to other fishes, relying on a combination of zooplankton, fish and benthic resources as energy sources. Food web metric analyses showed generally overlapping trophic niches for members of Chirostoma, especially in terms of δ13C. However, C. jordani had lower mean δ15N isotopic values than C. promelas. As a group, “pescados blancos” (C. sphyraena and C. promelas) also had higher δ15N signatures than “charales” (C. consocium, C. jordani and C. labarcae) reflecting greater piscivory, but these differences were not strong for all food web metrics used. Trophic overlap among species of Chirostoma in Lake Chapala raises questions about the forces that might have led to a morphologically diverse but functionally similar and monophyletic group of species.
AB - We explore the trophic role that a diverse sympatric group of fishes in the genus Chirostoma play in a large, shallow lake in central Mexico, Lake Chapala. We use δ13C and δ15N stable isotope – based food web analyses to explore how they relate to other components of the Lake Chapala ecosystem. We find five Chirostoma species in top trophic levels of the Chapala food web compared to other fishes, relying on a combination of zooplankton, fish and benthic resources as energy sources. Food web metric analyses showed generally overlapping trophic niches for members of Chirostoma, especially in terms of δ13C. However, C. jordani had lower mean δ15N isotopic values than C. promelas. As a group, “pescados blancos” (C. sphyraena and C. promelas) also had higher δ15N signatures than “charales” (C. consocium, C. jordani and C. labarcae) reflecting greater piscivory, but these differences were not strong for all food web metrics used. Trophic overlap among species of Chirostoma in Lake Chapala raises questions about the forces that might have led to a morphologically diverse but functionally similar and monophyletic group of species.
KW - Charales
KW - Food web
KW - Menidini
KW - Pescadoblanco
KW - Shallow lake
UR - http://www.scopus.com/inward/record.url?scp=84937911261&partnerID=8YFLogxK
U2 - 10.1590/1982-0224-20140079
DO - 10.1590/1982-0224-20140079
M3 - Artículo
SN - 1679-6225
VL - 13
SP - 389
EP - 400
JO - Neotropical Ichthyology
JF - Neotropical Ichthyology
IS - 2
ER -