by Victor W. Fazio, III
| Spring 2000 Bird Review by Victor W. Fazio, III |
Coverage map for seasonal reports |
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Although suburban Red-shouldered Hawks in SW Ohio are apparently maintaining their population and reproducing well, the outlook for these birds is unclear. On the outer edges of the study area most distant from the city of Cincinnati, agriculture dominates the landscape, and Red-tailed Hawks may outcompete Red-shouldered Hawks. The second major threat to Red-shouldered Hawks of SW Ohio is continued urban sprawl and suburban development. Although Red-shouldered Hawks can nest in suburban areas, they have been pushed out of traditional nest sites by development, even within the last 30 years. In a sample of 22 nests studied in SW Ohio in 1963 - 1977, only 10 of them still held Red-shouldered Hawks by the time of our study. Thus, it is unclear whether the suburban Red-shouldered Hawk population in SW Ohio can sustain itself in the future.
For the past twenty years, the Army Corps of Engineers has operated Dike 14 as a dredge disposal site. Currently, the lakefront property has been handed over to the Cleveland Port Authority and future plans for the land are pending. Several alternatives regarding land allocation are being considered, such as a bird sanctuary, state nature preserve, or a recreational park. Twenty years of bird census data and current land usage by 34 species of high conservation priority reveals that a bird sanctuary is a more ecologically sound alternative.
The first “early spring” to impinge upon the consciousness of modern birders in the midwest may well be the El Nino influenced season of 1983. Certainly it was one remarked upon widely for its record early arrivals in the region to a degree that stands out from the decade before. The next two years were veritable repeats of the pattern with many more record early arrival dates falling. While particularly dramatic, this pattern of early springs likely has deeper roots. In a 1985 report for Long Point Bird Observatory, I compared average arrivals for warblers of the most recent 9 year period against the previous 15 years, dating back to the beginning of station logs in 1960. For a half-dozen species, arrivals were a week or more earlier during the latter period. This was my first hint that by the mid-1980’s, the Lake Erie region was well into a trend toward early spring arrivals. Fifteen years later, the accumulated anecdotal observations of Ohio birders have only affirmed that the trend continues.
How much of this trend is real and how much may be ascribed to sampling error remains to be examined. For now, I direct your attention to additional evidence provided in the spring of 2000, a season not under the influence of the El Nino. Even a casual observer should have concluded the waterfowl had not only gotten an early start but had completed their passage well before the normal peak (most especially look at Tundra Swan and bay ducks). The plasticity in the chronology of waterbird movements is well-known and may not be the best measure of the spring migration chronology in general. Songbirds, in particular insectivorous neotropical migrants, may better serve the purpose. The swallows and the flycatchers include members spanning a variety of ecological niches. One is immediately struck by the number of swallows involved in overflights (*see below). Often these events may be dismissed with regard to arrival dates as they are assumed to involve odd-ball individuals moving under freakish weather conditions. Yet, in almost every case this sping, the abnormally early arrival involved birds at known nesting sites, not at migrant traps. As a group, the flycatchers were also very early. Not merely as a bird here or bird there, but several birds, across the state, reported by different observers, suggesting this was perhaps more than a chance event.
While birders are keen to focus on the arrival of species in the spring, average peak dates, and the onset of nesting behavior too can provide clues to the chronology of the spring. This type of information receives much less attention but several clues are given within these pages. The breeding records for Killdeer for their respective areas were at the recognized early extreme, while Hermit Thrush and Carolina Wren were nesting well before the early dates for the species. Birdlife is very dynamic; part of the attraction to birders. For perhaps more than 2 decades we have been experiencing an interesting dynamic involving the chronology of the seasons. It is the daily observations, reported to the ornithological record, that may be of use to those in the future who would discern something of the nature of this dynamic. - V.W.F.III
*Overflight: a biological phenomenon whereby a bird overflies, in time and space, its anticipated arrival by fully one migration wave. Spring migration waves are closely associated with weather fronts. Spring frontal passage through Ohio averages 6 days, therefore the occurrence of one or two birds 8 days, in time and space, ahead of the general arrival for the species, provided overflight conditions exist, is conservatively given as an overflight.
An outdated file version listing contributors mistakingly went to press resulting in these ommissions. My apologies for any inconveniences this may cause.- V.W.F.III
The Upland Sandpiper and American Golden-Plover records attributed to C.B. should be attributed to C.Bo. (Charlie Bombaci).
An apparent Sandhill Crane family at Killdeer Plains W.A.(Wyandot Co.) in late July - photos courtesy Ron Sempier.
