After 1936, a series of inconclusive expeditions and unconfirmed sightings acted as a substitute for solid evidence of the thylacine's continued existence and location.  The superficial resemblance of thylacines to dogs added difficulty to the problem, especially in instances of poor lighting conditions.  Also, to the untrained eye, thylacine tracks can be readily confused with those of wombats, especially if the soil is well compacted.  In May 1937, Roy Marthick searched for thylacines for three weeks, and claimed that he had discovered the tracks of twenty individuals, as well as actually seen some of the animals at dusk (Grzimek 1967).

. The Franklin River in western Tasmania.

. Another view of the Franklin River.

Two more expeditions followed, funded by the Animal and Birds Protection Board.  Trooper A. L. Fleming  and prospector Lesley Williams set out on 28 November 1937 into Tasmania's sparsely populated west coast, most of which was inhospitable to hunters (Fleming 1938).  After arriving at the Cardigan River, they proceeded to climb the hills to south of the Raglan Range and passed through a valley to the Franklin River and Fenchman's Cap.  Along the way, they encountered several thylacine tracks.  Additional tracks of a large and a small animal were found to the west of Frenchman's Cap.  Southward of the southern extent of the Raglan Range, they found eleven tracks from at least four different individuals, all inside a radius of 16 km.  The following year, Fleming made another excursion into the region directly to the southeast of the first (Sharland 1939).  After crossing the King William Range and the Jane, Franklin and Lodden Rivers, they proceeded into the beech forest of Thirkell's Creek and made some plaster casts of thylacine tracks.  They also saw the footprints of a domestic dog.  Having set up camp in a logger's cabin on the Erebus River, they surveyed an area of 2000 km between the King William Range and the Jane River hills.  They discovered tracks near a tributary of the Jane River, as well as high upon the slopes of Frenchman's Cap.

Additionally, they found tracks around their own cabin, which they claim was visited by a thylacine at night.     Between late 1943 and early 1944, a former thylacine hunter named Charles Spencer was cutting a track when he witnessed a beautifully marked individual "a least six feet from tip to tip."  He also remarks that he had seen a female with young at Adamsfield the previous March (Spencer 1944).

. Frenchman's Cap, western Tasmania.

    David Fleay, who was seeking a thylacine for the Healesville Sanctuary, led a search for the animal in November 1945. The expedition was based at a slab hut on the Jane River.  Traps were set up along the Erebus River.  The many discomforts of this trip are well summarized by Fleay himself (1946):

    "We lived in a heavy rainfall belt, usually with eight days wet out of ten and not uncommonly summer snow and frost; we struggled with Horizontal Scrub and clinging Bauera, or walked through dark and silent forests of dripping myrtle sassafras, leatherwood and pine.  Floundering journeys with heavy packs and equipment across boggy button-grass plains and strenuous climbing over high ranges were every-day events, not to mention the endless torment from mosquitoes, blow-flies, biting fleas, even rheumatism."