Here is the relevant part of a January 8, 1949 letter to Tanner from a former student, Arthur MacMurray, who visited the Singer Tract in December, 1948.
Jackson references the letter, and a brief excerpt is included in this history of the Singer Tract, but I think the discussion of ivorybills is worth reading in its entirety. Although, the letter is pessimistic about the future of the species, it provides about as credible a report of a pair as could be expected under the circumstances and extends the survival date far beyond Eckelberry’s last, lone female in April 1944 or Peterson’s 1946 date for the last bird. There’s no further correspondence about the Singer Tract until years later. Thus ends (inconclusively) the story of the Singer Tract ivorybills.
“The Singer Tract has been cleaned of all its commercial timber as far as I could gather. No Ivorybills have been seen at John’s Bayou for at least three years, according to a resident who has lived adjacent to it for twenty-two years. John’s Bayou has a lumber railway passing thru it and passing all the way north to some point due west of Tallullah. The Ivorybills apparently left John’s Bayou soon after the large gum tree which had been their nest tree for several years was lumbered. [Note: this probably refers to a roost tree, not a nest.]
Mr. Gus Willett is still the local game warden. I phoned him. He expresses his best regards to you. He says that only one pair of Ivorybills are known to be in the region (seen in late November), having moved to North Lake #1. He says that whatever Ivorybills are left are apparently wandering over much larger areas than formerly. He says that all the old stands of gum tree are being lumbered now or very soon, so he thinks the prognosis for Ivorybills is dark and apt to be very brief. He doesn’t know whether or not Ivorybills have been found elsewhere in Louisiana or elsewhere in Florida in the past few years.
A friend of the gentleman who resides adjacent to John’s Bayou reported that he saw what he thought was an Ivorybill on E.C. McCallip’s property on the Little Fork Road 6 miles south of Waverly on December 17th of 1948 [This would be just north of the Singer Tract.] So Dot and I spent the night in Tallullah and visited McCallip’s place (minus boots – It was very muddy) All the land we saw looked cut over. There were lots of woodpeckers. Saw 5 Pileateds but none of their cousins. I questioned Mr. Ward Williams (address: Del Hi, Route 1, Box 184-A, Madison Parish, Louisiana) who recognizes Ivorybills and distinguishes between them and the “native” (pileated) peckerwoods. He claims to have seen an Ivory Bill there in November. He regards them as nesting residents and thinks he can find a nest of them there without very much hunting. I left my address, and he intends to write next time he sees a bird. He and his visitors were aware of Ivorybills having been at the Sharkey place adjacent (or in) to Singer Tract.
Dot and I found it expedient under the murky circumstances to proceed on to New Orleans for Xmas day.
. . .
Wish I had more optimistic new regarding the what kind of future we dealt the big-woods peckerwood.
Best Regards,
Arthur”
A bit of a clue there, in the lower-density IBWOs beginning to roam more?
That makes intuitive sense, but there’s a good deal of conflicting information, and I doubt density has much to do with it; the John’s Bayou birds seemed to limit their movements when logging began in earnest. It’s not clear whether the family group Bick saw in ’41 in the vicinity of the “last” roost tree were the John’s Bayou family or another group altogether. Density was very low by ’37. I suspect the greater mobility was a result of habitat degradation, but ultimately, I just don’t think there’s enough to go on.