TY - JOUR
T1 - Abundance and reproduction of toads (Bufo) along a regulated river in the southwestern United States
T2 - Importance of flooding in riparian ecosystems
AU - Bateman, H. L.
AU - Harner, M. J.
AU - Chung-MacCoubrey, A.
N1 - Funding Information:
The Middle Rio Grande Conservancy District permitted access to study sites. Sampling techniques were approved by University of New Mexico Animal Care and Use Committee protocol (#20415). This study was funded by the USDA Forest Service—Rocky Mountain Research Station (RMRS), Middle Rio Grande Ecosystem Management Unit, Joint Fire Sciences Program, National Fire Plan, US FWS Bosque Improvement Initiative, and USFS State and Private Forestry New Mexico Collaborative Forest Restoration Program. Additional support to Heather Bateman was provided by University of New Mexico (UNM) Graduate Research Development Grants, UNM Grove Grants, and a National Fish and Wildlife Foundation Grant. Mary Harner was supported by an NSF Integrative Graduate Education and Research Training Award (DGE-9972810) in the Freshwater Sciences Interdisciplinary Program at UNM. We thank Deborah Finch (RMRS) for support of this project. We also thank Roy Jemison (USFS), Mike Campana (UNM), and Christian Gunning (UNM) for sharing well data. We thank RMRS field assistants for monitoring herpetofauna, with special thanks to L. William Gorum and Heather Maccurdy. We thank Kenneth Geluso, Ursula Shepherd, and an anonymous reviewer for comments on the manuscript. Clifford Crawford and Howard Snell provided insightful discussions about this research.
PY - 2008/9
Y1 - 2008/9
N2 - Abundance and size of toads (Bufo woodhousii and B. cognatus) were related to precipitation, river flow, and groundwater over 7 years along the Middle Rio Grande, a regulated river in the semi-arid southwestern United States. Toads were monitored in riparian areas at 12 sites spanning 140 km of river during summers 2000-2006. Regional precipitation varied between years, with occurrence of both drought and record high precipitation. Abundance of toads was low during most of the study (mean=11 captures/month/site). However, two sites flooded in spring 2005, resulting in a dramatic increase in captures at those sites (mean=214 captures/month/site). Most individuals captured in 2005 were small (median body mass 0.6 g), suggesting that toads used the floodplain for breeding during the flood. Only river flows that exceeded 100 m3/s brought groundwater close enough to the surface to create pools used by toads for reproduction and development. Such flows were once common along the Middle Rio Grande but are rare following regulation. Our results demonstrate that small, managed floods can positively affect abundance of toads by providing off-channel, aquatic habitats along regulated rivers.
AB - Abundance and size of toads (Bufo woodhousii and B. cognatus) were related to precipitation, river flow, and groundwater over 7 years along the Middle Rio Grande, a regulated river in the semi-arid southwestern United States. Toads were monitored in riparian areas at 12 sites spanning 140 km of river during summers 2000-2006. Regional precipitation varied between years, with occurrence of both drought and record high precipitation. Abundance of toads was low during most of the study (mean=11 captures/month/site). However, two sites flooded in spring 2005, resulting in a dramatic increase in captures at those sites (mean=214 captures/month/site). Most individuals captured in 2005 were small (median body mass 0.6 g), suggesting that toads used the floodplain for breeding during the flood. Only river flows that exceeded 100 m3/s brought groundwater close enough to the surface to create pools used by toads for reproduction and development. Such flows were once common along the Middle Rio Grande but are rare following regulation. Our results demonstrate that small, managed floods can positively affect abundance of toads by providing off-channel, aquatic habitats along regulated rivers.
KW - Amphibian
KW - Groundwater
KW - Managed flooding
KW - Middle Rio Grande
KW - New Mexico (USA)
KW - Off-channel aquatic habitat
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U2 - 10.1016/j.jaridenv.2008.03.009
DO - 10.1016/j.jaridenv.2008.03.009
M3 - Article
AN - SCOPUS:45449089634
SN - 0140-1963
VL - 72
SP - 1613
EP - 1619
JO - Journal of Arid Environments
JF - Journal of Arid Environments
IS - 9
ER -