C&O Canal 2002 Report
Overview
Results of the Fourth Annual Chesapeake and Ohio Canal National Historical Park Mid-Winter Bird Survey have been tabulated.
We had a good time, and collectively saw more species (91, excluding feral waterfowl) and individual birds (23,000 by one measure; see totals on spreadsheet) than in any of the previous years. Seven species were new to this count - Double-Crested Cormorant, Ring-Necked Pheasant, Northern Bob-White, Red-Headed Woodpecker, Fox Sparrow, Savannah Sparrow, and Brown-Headed Cowbird.
Coverage and Participation
Saturday, January 26, 2002 was fair, with morning temperatures below freezing, but rising to the 60’s during the day. The forecast and actual good weather, in contrast to the first three years of the count, led to our best coverage so far. 178 mile-segments (milepost to milepost) were covered, out of a possible 185, over 96% of the Canal’s length. The 178 figure does not include segments counted for 0.5 miles or less, or observed in passing en route to an assigned area, although these observations contribute to species totals and to mile-by-mile data where they can be so assigned. At least 118 individuals participated. The 64 listed as “other team members” by the 54 nominal principal observers included regular birding companions, and some pre-eminent contributors to Maryland-DC birding, but also interested beginners. The count in Miles 100-103 constituted a field trip for four George Mason students in Steve Sheffield’s ornithology course.
Our elusive goal of 100% coverage would have been easily achieved, but for miscommunications and misunderstandings, ultimately the organizer’s responsibility. We had duplications as well as gaps, noted in the spreadsheet comments. We will try to eliminate these in 2003.
Generally, the Montgomery County mileage is oversubscribed; the western Allegany County mileage hitchhikes on that MOS chapter’s mid-winter count, and Washington County and the eastern Allegany County mileage is the area most in need. We were glad that some strong birders were able to join our count for their first time in 2002. Several veterans must be mentioned individually, within this broad-based effort. Deanna Dawson (author of invaluable checklists for NCP-E) and John Sauer counted Miles 88-93 on foot, and Miles 86-87, where the towpath is closed, by canoe. Dianne Ingram, coordinator of the BBS for the C&O, dropped off and picked up DC birders along the towpath in the lower Allegany County stretches, also accompanying Peter Vankevich, who founded this count (as well as two coastal NC Christmas Counts) in Miles 157-160. Mary Huebner of Little Orleans covered Miles 136-139 and with Steve Huebner lodged and deliciously fed our entire DC delegation. Teresa Simons coordinated the Allegany County mid-winter count on the same day, and we shared the observations of five of her stalwarts (with an unfortunate duplication at that), who among them covered the westernmost 17.5 miles.
Data Presentation
The spreadsheet for the 2002 count is a 130kb Excel® 5 file, displayable with Windows® 95 and newer platforms, which may prompt for conversion to later versions of Excel. The file can be found here. It will print legibly on eight 8.5”x14” pages, numbered left to right (ascending mile-segments of the Canal) and then top to bottom (non-passeriforms and passeriforms), plus three pages of comments on particular mile-segments. Each of the eight pages displays a species column, a mile-segment row, and a row with initials of the reporting observer. Column totals are the number of species and numbers of individual birds in a mile-segment. Row totals are, for each species, the total number counted and number of mile-segments in which any were observed. Pages 4 and 8 display comparative aggregate data from 1999-2000-2001. Comments on certain mile-segments are flagged by a red dot in the display, and appear at the end, on pages 9-11 of the printout. The comments can be reformatted to display and print near the cells to which they relate. Spreadsheets for 2001, 2000, and 1999 are in a similar format, also Excel® 5.
The mile-segments are numbered starting with “0”, and thus correspond to the milepost marking the downstream terminus of that sector. This numbering is the least confusing way to report segments covered, and to correlate with the instructions provided to participants, and maps and descriptions in Hahn’s Towpath Guide. The order of species is the same as on the checklist provided to participants.
Quality of the Data and Reporting
Extra independent counts of mile-segments, whether purposeful by a participant’s passing through to another segment or due to miscommunication, produced a lot more species and birds. This is was the case whether or not the counts were close together in time, and is unsurprising, given the mobility of winter foraging-flocks and of most of the non-passerines. As a true population census, this count is not in the ballpark with the survey reported in Hatfield et al., Maryland Birdlife 50:1-4. Since “party-hours” is not a compiled datum, this count is even less normalized in respect of observational effort and opportunity than are the Christmas counts. Like the Christmas counts however, the sheer mass of data, with its limitations understood, will tell a story over time. The appeal of this count, and such internal comparability as it has, derives from its mile-by-mile character.
Obviously some birds appear in different miles and get counted more than once. Only in a few cases can the compiler correct for this with any degree of confidence. Generally, what is reported is what is tabulated, and hopefully double-counted birds make up for missed birds. Nevertheless, recording starting and ending times for each mile-segment, as indicated on the form of checklist, is very helpful. So is noting the time, rough location within the mile-segment, and direction of flight or float for any really large flocks, and any really unusual sightings (plus maturity and sex, if observable.)
More generally, all the information requested on the checklist should be furnished, and I appreciate all those who did so. The species and individual totals are useful asa check against either recording or data-entry errors. Observers’ notes and comments are always interesting and useful for assessment and planning. This year we had comments on mammals seen, on human activity (lots of hikers and bikers even early in the morning, shooting and fishing at various locations, apparent paucity of one or another species or family, and general impresssions.)
Species Comments
The 2002 absolute totals reflect increased coverage and participation, and the fine weather. It is not certain that a high or low count for any species reflects real numbers present, as did, for example, the 211 Sapsuckers in 2000.
A DC cormorant in DC and one (maybe 2) in a Montgomery sector are new to the count. Formerly absent from the Washington DC Christmas Count, they have been regular in recent years.
Both Vulture numbers were up, in good soaring weather. The commoner raptors (Bald Eagle, Sharp-Shinned, Red-Tailed, Red-Shouldered), likewise.
Waterfowl: Canada Geese were again the most numerous species, beating out Common Grackle, though both numbers are rather arbitrary. Five white-morph Snow Geese were in Mile 101, but not the Blue Goose of 2000 and 2001 in Mile 97. Comments by John Trapp (of FWS) on the domestic ducks he observed appear in Miles 97 and 99. Several participants commented that duck numbers were low, and indeed, no species set new highs in 2002 for either number of birds or number of segments
Galliforms: One Pheasant in Mile 106 and one Bob-white in Mile 47 were new to the count. The latter was identified from its call; rarely given in winter, but the circumstances were convincing. An early morning flock of 50 (accurately counted) Turkeys in Mile 143 was enjoyable.
Woodpeckers: Red-Headed was a first for this count. Two in the Seneca area were anticipated, andt another singleton was seen in Mile 177. Downy Woodpecker, recorded from 155 segments, beat out its woodland companions as the most widespread species.
Chickadees: These are tabulated largely as reported. Descriptions should be mandatory for Carolinas above Mile 140 or Black-Cappeds below Mile 80, and highly desirable within that range.
Sparrows: Several observers mentioned .few or no sparrows in their sectors. As with the ducks, no sparrow species set new highs in 2002 for either number of birds or number of segments. However, one Savannah Sparrow was an overdue first for the count, as was one Fox Sparrow, perhaps even more overdue in terms of likely habitat.
Icterids: One Red-Winged Blackbird in DC preserved the honor of North America's most abundant landbird. Grackles are rare on this count, so a huge grackle-cowbird flock surprised the observer in Mile 71. The Brown-Headed Cowbirds were actually a first for the count, though Jim Paulus, whose passing this year was sadly noted, recorded one last year from a vantage point just outside the Park boundary.
Nine Purple Finches in six segments compares with one bird in the previous three years; this might be real, but I haven't checked the seasonal reports for the region generally..
Back to C&O Canal page.
