Discovery of fossil avian footprints from Late Holocene sediments of Allahbund uplift in Great Rann of Kachchh of Western India

The Great Rann of Kachchh is a sabkha terrain with a thick succession of Quaternary to Late Holocene sediments, deposited during high sea level after the Last Glacial Maxima. Geomorphologically, the Great Rann of Kachchh is subdivided into Bet Zone, Linear Trench Zone, Great Barren Zone, and Banni Plain. The Bet zone is a slightly elevated flat surface comprising a complex network of bets and interbet channels-the geomorphic entities developed as complex interplay of sea level and coseismic tectonic activity during the Holocene. Moreover, during the last 5.5 to 2 ka, the central part of the western Great Rann was under the influence of tidal flat sedimentation. The present study at Karimshahi Bet/ Allahbund (the western portion of the Bet zone) records the first group of avian tracks of shorebirds from Late Holocene sediment preserved at a depth of 15 cm below the present-day Rann surface. According to the morphological and preservational study, the footprints are classified as cf. Gruipeda, suggesting the trace maker as waders (Shorebirds) foraging on the shoreface. The discovery of avian trackways and abundant shallow marine ichnoassemblage within the studied unit suggests that the area was flooded by low-energy water, forming a favourable habitat for waders (shorebirds) to forage shoreline. Thus, the work describes the first-ever record of avian shorebird tracks from the Late Holocene mudflat succession of Great Rann of Kachchh, Western India.