Eos, Transactions American Geophysical Union

New mechanisms studied for creek formation in tidal flats: From crabs to tidal channels



Mechanisms for the formation of creeks in tidal flats are rarely discussed in the peer-reviewed literature. Moreover, while there are general theories about how creeks form in tidal flats, there is no data to support these theories. It is generally believed that marshes inherit creeks from previous tidal flats that plants colonize, and that further modify the creeks. Recently, we have discovered new mechanisms for creek formation in three different environments of Argentina in which tidal creeks are actually originating in both fresh and salt marshes. One of the most surprising and interesting findings is that creek formation can actually be a product of the intense action of crabs (Chasmagnatus granulata). In these settings, crabs first interact with a halophytic plant (Salicornia ambigua), developing zones of high-density of crab holes, which then are utilized by groundwater and tidal action to form channels. This specific interaction forms a series of rings that, to the best of our knowledge, have not been described elsewhere in the literature.