Mangrove Blue Flycathcer Cyornis rufigastra, a take-for-granted flycatcher that inhabit coastal mangroves, coastal peat swamps, coastal forests and on offshore islands.
Quentin Phillips in his Field Guide to the Birds of Borneo states that it is sometimes found inland, overlapping Malaysian Blue Flycatcher Cynornis turcosus, this is proven true when this pair was photographed in Tawau Hills Park, foraging in and out of the forest edge to the adjacent oil palm plantations for consecutive two week-ends.
If you look at Google Maps, you can see that Tawau Hills Park is absolutely non-coastal.
So, take a closer look when you encounter a blue flycatcher inland, it might be a Mangrove Flycatcher instead of the expected Malaysian Blue or Hill Blue.
Happy birding.
