It is not very often that an accurate comparison of observed bird species can be made across a span of a hundred or so years, but with the just completed spring bird count on May 9, 2009 for Sarpy County, Nebraska, the essential details are available.
Blue-gray Gnatcatcher. Image courtesy of Matt Sittel, with further images of birds of the forest area at his website. |
Historically
The 1908 observations were by members of the Nebraska Ornithologists' Union during a spring meeting during the May 9-10 weekend. Their field trip was made to the woodlands northeast of Bellevue, which at the time was known as Childs Point and was a celebrated haunt of wild birds and their watchers for many years from prior to 1900 and into subsequent years.
The date of comparison is May 9-10, 1908, when another group of ornithologist's walked about the same environs and noted what species they observed.
Memoirs by the celebrated naturalist Frank H. Shoemaker his records are housed in the University Archives at the University of Nebraska-Lincoln convey the details for the historic character of the place. He wrote these words about the place about the turn-of-the-century, around 1900:
"The valley of the Missouri River immediately below the city of Omaha lies between steep bluffs, the river skirting the base of those on the Nebraska side, while on the Iowa side there intervenes a broad, flat area, much of it subject to overflow during periods of high water. Several miles below the city on the Nebraska side is a heavily wooded tract, extending over the bluffs and well back from the river, which at this point sweeps away from the base of bluffs and leaves a broad, flat expanse overgrown with cottonwood and willows. Numerous springs in the bluffs mingle their waters in a narrow, reed-grown stream, which soon spreads over a wide area and forms a marsh, filled with rushes, reeds and cattails. Back from the river the surface is rugged and hilly, covered with heavy woodland and undergrowth, traversed by several broad, grass grown valleys and numerous deep, shady ravines. This woodland continues to the summit of a ridge which roughly parallels the valley of the river; beyond this point lie fertile fields. In summer the lesser vegetation is very heavy, the bottomlands particularly being covered with an almost impassable tangle of vines and weeds, while many places on the bluffs are overgrown with dense thickets, though that region is chiefly woodland, of every character from tracts of stunted second growth to extensive areas covered with massive oaks and lindens.
"This section is known locally as the Childs' Point region for want of distinguishing terms for its various portions, though strictly speaking, the "Point" is a small part of the area so designated. Rounded by the river, and embracing areas so distinct in character - sandbars, bottomlands, marshes, occasional small bodies of open water, dense thickets, timberland of diverse character, and open fields - this region is peculiarly fitted to attract a great variety of birds."
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Results from the NOU meeting were published in their transactions, with the notes on the species observations entered into a database of historic records of Nebraska birds.
Modern Times
The Sarpy County Spring Bird Count, coordinated by Clem Klaphake, with participation of his students of the bird class available through Metropolitan Community College, and with the essential assistance of other local birders, were about the region on May 9, 2009.
The bird list was provided by Justin Rink. Other participants included Elliott Bedows, Rick Schmid, Brian Hula, Nelli Falzgraf, and Jim and Sandy Kovonda, according to Matt Sittel, also helping with the survey.
Environs of Fontenelle Forest was an essential part of the survey area, as there had been numerous notations of observed species presented by reports on NEBirds, for previous days and weeks. The place with its diversity of floodplain and bluff habitats, is a magnet for birds and the people whom watch them, and usually report what they saw.
According to issued reports, this spring count was one of the most successful, with a large diversity of observed species. In particular, the species seen at Fontenelle Forest was also impressive, although it was just one place where the bird watchers traversed.
Bird-Watcher Results
The observations recorded by accomplished birders of the NOU in 1908, along with the notes by the modern-day equivalent, provide a list of 131 species for this geographic locality.
There would likely not be any variability due to skills of the observers, as there were accomplished bird-watchers both instances. Any differences would be due to changes in habitat at the locale, and any variance in the migration times of the species.
- Childs Point, May 9-10, 1908: 89 species
- Fontenelle Forest, May 8-9, 2009: 111 species
- Combined species tally: 131 species
There are further details to consider.
These are the species noted in 1908, but not during the recent count, with some considerations as to why they may not have been sighted in 2009:
- Northern Bobwhite: lack of suitable habitat due to a decreased extent of agricultural habitat on the point
- Semipalmated Plover: lack of sandbar habitat due to channelization of the Missouri River
- Ring-billed Gull: lack of riverine habitat
- Yellow-billed Cuckoo: could be readily expected, but just not observed
- Belted Kingfisher: could be readily expected, but just not observed
- Horned Lark: potentially may occur in the agricultural fields of Gifford Farm
- Bank Swallow: could be readily expected, but just not observed
- Red-breasted Nuthatch: could be readily expected, but just not observed
- Blue-winged Warbler: could be readily expected, but just not observed
- Magnolia Warbler: could be readily expected, but just not observed
- Cerulean Warbler: not observed on count day, but was noted on May 14th, by Justin Rink
- Canada Warbler: could be readily expected, but just not observed<
- Yellow-breasted Chat: change in species range so this species is less likely to occur in the Missouri River valley
- Field Sparrow: still occurs in the vicinity, but not observed on during the modern count period
- Lark Sparrow: there is a lesser extent of the habitat utilized by this species, though it has been seen at Fontenelle Forest in recent years
- Savannah Sparrow: a lesser extent of open-field habitat
- Grasshopper Sparrow: there is little grassland habitat present, which is required by this species
- Blue Grosbeak: could be readily expected, but just not observed
- Dickcissel: present a few years ago, so it may have not been noted as the count area did not extend to Gifford Farm which comprises the oxbow lands east of Fontenelle Forest
The Ring-necked Pheasant and European Starling had not yet been introduced in this region of the river valley in 1908, while they are a prevalent species in the modern era.
Several of the species noted historically, also occur in the modern-era, but their migration time this particular season may have meant that they were not present at the time of the 2009 Sarpy County Spring Bird Count.
Notably, there are some interesting species noted in 2009, but not in 1908. Consider:
These wetland habitat associated species, Canada Goose, Wood Duck, Mallard, Pied-billed Grebe, Double-crested Cormorant, Great Blue Heron, Great Egret, Sora, Spotted Sandpiper, Greater Yellowlegs, Pectoral Sandpiper, Black Tern, and Sedge Wren that would utilize the Great Marsh on the floodplain of the forest area, a tract which has been enhanced by restoration work associated with the Missouri River mitigation efforts. These species would also occur in this area historically, but perhaps the NOU group did not get down to the river bottoms and its wetlands.
Wild Turkey: prevalent due to successful, modern introduction of the species.
Eurasian Collared-Dove: a species only recently extant in Nebraska
Variability in the observation of different warbler species may just be a result of migration times for a particular species.
A comparison of the occurrence of the Orchard Oriole - not noted historically but seen in 2009 - may be due to sighting variance, as the habitat historically and currently would be expected to be suitable.
There was more upland grassland habitat in 1908, which accounts for the Western Meadowlark being noted, whereas this species would not be expected at all now. This would also be a factor influencing the occurrence of the Grasshopper Sparrow.
As for the House Finch, the expansion in range of this species makes it a prevalent species now, whereas this would not have been the case a century ago.
In 1908, the House Sparrow was still a relatively new species on the scene, though Frank Shoemaker noted it as a common resident in 1900 at Childs Point. However, the next information about this species at this locality was in 1939.
Considerations
The ornithology of Nebraska is just starting to enter an era when the records from historic times can be compared to what was noted in decades past.
Most importantly, it is essential that the records kept for species provide a thorough list of species for a particular locale. Providing the numbers of each bird type observed is also very valuable as a means to compare abundance.
This comparison uses only two sources of information. With a broader extent of details from different period of times during different decades, other evaluations can be made using a record-based analysis.
For Nebraska, there will be additional evaluations possible, as the record-base for the state is more extensive subsequent to the instance considered here.
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