Khor Kalba, straddling the border with Oman, supports the only mangroves on the UAE’s east coast. These are home to an endemic subspecies, kalbaensis, of white-collared kingfisher (Todirhamphus chloris), which breeds only here. Less than fifty pairs are present and it is thus one of the rarest subspecies of bird in the world. The kingfisher feeds almost exclusively on crabs, something local children find it hard to resist collecting too. 
Khor Kalba is, not surprisingly, scheduled to be designated a nature reserve by the authorities in Sharjah emirate, to which it belongs.