Robert Warren was born in Cork and spent his early years at Castle Warren, his father’s residence in that vicinity. He early formed a friendship with J. R. Harvey of Cork , and became a correspondent of William Thompson of Belfast , for a taste for natural history was born with him; Thompson quotes from his letters frequently in his Natural History of Ireland . In 1851 the family home was transferred to Moyview in Sligo . Here, on the estuary of the River Moy, with the sands of Killala Bay and of Bartragh Island close by, he availed himself fully of excellent opportunities for the study of bird life, and this continued until his death. In 1890 the book on the birds of Ireland, which was ultimately published under the names of Ussher and Warren, was planned, with Barrington, More, Ussher and Warren as joint authors: but in the issue the entire work of preparation fell on Ussher, since More suffered from ill-health, Barrington was much engaged on his migration reports and Warren did not feel himself sufficiently equipped for so wide an undertaking.

The preface of Birds of Ireland, Ussher & Warren cites  

Robert Warren has written the articles on white wagtail, surf scoter, spotted redshank, greenshank, Bar tailed godwit and Sandwich tern, and though not responsible for the rest of the work, which is written by R.J.Ussher, the former has contributed from his personal observations, which have continued for nearly fifty years and habitually noted down at the time. These supply a knowledge of the waders and wildfowl of northern connaught, which find in the broad but tapering bay of killala a harbour of refuge when they arrive from the north or follow the cliff bound coasts of mayo. The long island of Bartragh acts as a breakwater, inside which there are extensive estuarine flats that temp these wanderers to stay; so that a better point of observation in that little studied province could not be found”

The road to the Black stick

This roadway way originally used to cart goods to boats which would moor at a point just a hundred or so meters north of where the path meets the shore . Cargos of potatoes , grain were drawn by cart a section of the road aproximately at the half way point is wider to allow two carts to pass .

The old mooring post still remains and is known by locals as the Black stick,but is only visible when the tide is out.

The Warren Way is primarily a woodland walk however it is significant that it runs along open farmland, passes over a freshwater marsh and eventually leads to estuarine mudflats. The interaction between these different habitats gives rise to an incredible wealth of species in a relatively small area each in its own way dependant on another series plants or animals. 

While it is easy to see the plants which are growing along the way, many of the animals that frequent the vicinity are elusive and secretive to say the least, however patience and quiet can be incredibly rewarding.
This piece of woodland is dominated by ash, sycamore alder and willow and is relatively young probably no more than 150 to 200 years old we can tell this not only by the age of the trees but more significant by the absence of certain woodland species,wood arum, wood anemone do not occur here nor is there oak, birch, holly or hazel all species central to ancient native woodland. It is equally important that the wood has not as yet been infected with the modern invaders Rhododendron and Japanese knotweed both of which have the potential to destroy woodland and scrub habitats.

As a decidous wood the stark contrast of the seasons are incredible from the bare branches of winter through to dappled shade of summer  

Down on the mudflats a totally different cycle dominates the tide constantly on the move it ebbs and flows twice a day and with it waders curlews & godwits plovers and sandpipers move each keeping to its own depth and thus not competing with other species for food, godwits probe deep into the mud while wading through water too deep for smaller birds while redshank patrol the very edge of the water.

Whoopers, Wigeon & Teal and Brent arrive from Iceland in September. The Whoopers stay overnight on the estuary before heading inland to the lakes and turloughs of Mayo and Galway but the ducks and geese spread out over the estuary until April when they fly north again to their breeding grounds.

Huge flocks of golden plover gather on the flats and are joined by lesser numbers of small wader Sanderling, Knot, Ringed plovers & Grey plover. These flocks attract the attention of Peregrine falcons .

By May the flats will appear deserted the vast bulk of the birds will have moved to their breeding grounds be they in the Artic circle or on the bogs and mountains throughout Connaught & Ulster.July and August sees Terns and Godwits returning the the estuary flanked by this years young and the cycle continues just as Warren observed.