Response of shoal grass, Halodule wrightii, to extreme winter conditions in the Lower Laguna Madre, Texas

D.W. Hicks; C.P. Onuf; J.W. Tunnell

doi:10.1016/s0304-3770(98)00084-9

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Response of shoal grass, Halodule wrightii, to extreme winter conditions in the Lower Laguna Madre, Texas

D.W. Hicks·C.P. Onuf·J.W. Tunnell

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Abstract

Effects of a severe freeze on the shoal grass, Halodule wrightii, were documented through analysis of temporal and spatial trends in below-ground biomass. The coincidence of the second lowest temperature (-10.6??C) in 107 years of record, 56 consecutive hours below freezing, high winds and extremely low water levels exposed the Laguna Madre, TX, to the most severe cold stress in over a century. H. wrightii tolerated this extreme freeze event. Annual pre- and post-freeze surveys indicated that below-ground biomass estimated from volume was Unaffected by the freeze event. Nor was there any post-freeze change in biomass among intertidal sites directly exposed to freezing air temperatures relative to subtidal sites which remained submerged during the freezing period.

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D.W. Hicks, C.P. Onuf, J.W. Tunnell. 1998. Response of shoal grass, Halodule wrightii, to extreme winter conditions in the Lower Laguna Madre, Texas. https://doi.org/10.1016/s0304-3770(98)00084-9

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