06 May 2008

Expedition in 1853 Notes the Importance of Aransas Bay for Fowl in the Winter

During 1850-1853, an expeditionary force was assigned to define the northern boundary of Mexico. The leader of the United States-Mexican boundary Commission, 45-year-old John Russell Bartlett, kept a personal narrative of explorations and incidents in Texas, New Mexico, California, Sonora and Chihuahua.

The preface to the lengthy account said: "...of the botany and zoology I have endeavored to keep before the reader a correct idea of the character of the country throughout which he was to follow me, without lists and descriptions, scientific or otherwise, of every plant, quadruped, bird, and reptile that came in my way."

Notes about local birds among the daily diary entries, started soon after the party got underway. A first notation in September 1850, referred to prairie fowl, curlew and quail at Indianola, on the gulf coast of Texas. Subsequent mentions - only periodically in Bartlett's ongoing narrative - typically only cited one or two generic types of birds such as ducks, teal, plover, sparrows and blackbirds.

In one instance on October 20, 1850, when traversing a plateau near Bradys Creek in west-central Texas, a vast prairie dog town - including "small brown owls" that flitted about - was enough of an inspiration that Bartlett drew a sketch which also depicted the Burrowing Owls. The men and their wagons marched for three hours through the "dog-town," with it extending onward far enough to be present during the entire next day. On the 22nd, the day's entry said: "The community and domain of the prairie dogs, which we entered two days ago, continues." The locale may have been a wintering habitat for the owls. On the 23rd, more owls were noted when beyond "Potato Spring" and near Antelope Creek.

The brief mentions of birds for this expedition account are interesting records, but certainly are not a significant contribution to historic ornithology for the region visited.

However, near the end of the survey expedition early in 1853, Bartlett remarked on the conditions where a great number of fowl were present on the eastern extent of Corpus Christi Bay. This notation is exquisite for the inference of the presence of a particular species.

"January 5th. The morning found us on the opposite side of Corpus Christi Bay, a light breeze wafting us eastwards towards Aransas Pass. The navigation here is carried on with boats of light burden through the shallow bays or lagunas, which line the west and north-west shores of the Gulf of Mexico. These bays are exceedingly shallow, sometimes presented a breadth of ten or fifteen miles, by a hundred or more in length. Yet these broad spaces of water are often not more than three or four feet deep, even in the middle. This depth would admit flat-bottomed vessels of large capacity, were it not for the numerous bars which intersect them, sometimes leaving but a few inches of water; hence, none but flat-bottomed boats can navigate these waters, and even these may be suddenly arrested in their progress, should a norther occur and drive the water out of the bays.
"Our course lay through a channel less than twenty yards wide for miles, with bars of sand on both sides but an inch or two above the water. These were covered with myriads of water-fowl, including cranes, swans, herons, ibises, geese, ducks, curlews, plover, sand-pipers, etc. The large cranes and swans stood in lines extending for miles, appearing like a light sandy beach or white cliff; and it was impossible to dispel the delusion, until the vast flock, with a simultaneous scream that could be heard for miles, rose from their resting place. Occasionally, we would round a point which concealed a bay the surface of which was filled with ducks and geese; these, taking the alarm, would rise in one continuous flock, making a noise like thunder, as they flapped their wings on emerging from the water. Notwithstanding the vast numbers of these birds, I shot but few; for the water was so shallow that we could not get within gun shot of them with our boat. With a light skiff, and a few bushes or a bunch of grass, a gunnder would have such sport as no other portion of the world can surpass."

Their route continued until entering Aransas Bay, later in the day's boat trip, just days before Bartlett explorations were to end, and he returned to the east coast.

This entry is certainly notable for its mention of the large cranes, with its additional notation to their appearing as part of a "white cliff" with the swans.

This can be interpreted as referring to a large white crane, which can be readily distinguishable as the Whooping Crane, rather than the smaller, gray crane, which would be the Sandhill Crane. And the notation is about cranes, not herons, or egrets. It is possible that the Great Egret and Snowy Egret were also among the species present, since this is an area where the species would occur in January.

Bartlett's notes obviously indicate an extensive number of the particular cranes, spread along a distance given in "miles" rather than for just a short distance. There must have been a very large number present, indicating the importance of the locale as wintering habitat.

The scene was obviously remarkable, presenting an impression dramatic enough for Bartlett to mention a greater variety of bird types than he noted on any other occasion during the 2.5 years of the boundary survey.

More than 150 years later, Aransas Bay is still the winter home for the remaining remnant - compared to historic numbers - of the interior population of Whooping Cranes.

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