The 125th Christmas Bird Count in Pennsylvania

Pennsylvania birders made their usual excellent contributions to the Christmas Bird Count’s milestone 125^th season, as annually done since 1900. Eighty-one sites reported for Pennsylvania, one fewer than the previous year. The statewide effort of 5,592 party-hours was an eight-year low, the 756 feeder-watch hours was on the low side, but the 334 nocturnal hours was average.

The statewide total of count-day species was 157, an eight-year low and seven less than the trend indicates was expected. Bay-breasted Warbler at Dallas Area was a new species for the Pennsylvania CBC. A year after 21 species set new statewide high tallies for the Pennsylvania CBC, six species set new statewide highs this season: Eurasian Collared-Dove, Golden Eagle (tie), Bald Eagle, Merlin, Common Raven, and Orange-crowned Warbler. While 2023 was an exceptional year for high counts, this didn’t carry over to this season. Several northern species and several uncommon species that are often found were not found this time. However, six count-week species were not found on any Pennsylvania count day: Black Scoter, Red-throated Loon, Red-necked Grebe, Purple Sandpiper, and Snowy Owl at Erie, and House Wren at Southern Bucks County.

Southern Lancaster County was the top site for species number with 110 species, the most in Pennsylvania in 12 years; Southern Bucks County was second with 104 species; and Upper Bucks County was third with 99 species.

Waterfowl. A total of 118,000 Snow Geese were reported, with 76,000 at Lehigh Valley, 19,700 at Bernville, and 14,400 at Bethlehem-Easton. The 673 Snow Geese at Rector was unexpected. This total was the 9^th highest for the state CBC, but it was less than half of the 253,000 high count from 2019. Within the last three decades, Snow Geese have included the Lehigh, lower Delaware, and lower Susquehanna Valleys as part of their core eastern wintering area.

Four Ross’s Geese were observed, with two at Johnstown and singles at Lititz and Pittsburgh. Three Greater White-fronted Geese were observed, with two at Southern Lancaster County and one at Audubon. A single Brant was at Pittsburgh, only the 27^th time that Brant has been recorded in the state CBC and the first instance west of Chambersburg.

A total of 38 Cackling Geese at 14 sites was also a top 10 total, with the high being 11 at Lehigh Valley. The 135,000 Canada Geese were consistent with counts of recent years, but continued to be lower than during the peak period of 1998-2017, when totals exceeded 200,000 several times. The 126 Mute Swans were the fewest since 95 were tallied in 2000. Five Trumpeter Swans were reported, with two at York and singles at Erie, Southern Lancaster County, and West Chester. The 634 Tundra Swans were consistent with recent years, but many more were commonly counted not long ago. The high count was 5,093 in 1991, but the last time 2,000 were recorded was in 2012.

The 112 Wood Ducks was the 4^th consecutive year with a relatively high count. Blue-winged Teal was missed for the 4^th time in the last 10 years. The 472 Northern Shovelers was the 3^rd highest historical count and included 349 at Delaware County and 102 at Southern Bucks County. The 779 Gadwalls was the 6^th highest total and included 202 at Delaware County and 132 at Southern Bucks County. Gadwall is the one dabbling duck that clearly shows an increasing trend. Three Eurasian Wigeons were reported, only the 20^th year for this species in the Pennsylvania CBC and the first in 15 years. Two Eurasian Wigeons were at Upper Bucks County and one was at Southern Bucks County. Mallards and American Black Ducks have been experiencing long declines of about 24 and 54 years, respectively. Numbers have held relatively steady in recent years, so it is possible that the 16,989 Mallards and 2,035 American Black Ducks represent a bottoming out in the decline.

The 28 Canvasbacks continued their low numbers, while the 227 Redheads was a decent total. The 1,594 Ring-necked Ducks was 2^nd highest to 2023’s 1,842 and included 307 at Elverson, 302 at Southern Bucks County, 152 at Dallas Area, and 140 at Dubois. A total of 11,562 scaup were tallied, with 11,473 at Erie and 89 elsewhere. This was the 2^nd highest scaup total to the nearly 16,000 scaup reported in 2022, with all but 11 at Erie.

The only scoters were seen at Erie, including 7 Surf Scoters, 158 White-winged Scoters, and 33 scoter sp. Black Scoter was missed for the 3^rd time in the last 10 years.  The 158 White-winged Scoters was 2^nd highest to 2023’s 406.

The 40 Long-tailed Ducks at 11 sites was an average count. While Buffleheads have generally been increasing, the 970 total was several hundred lower than in the three previous years, with highs of 173 at Lineville and 147 at Erie. Hooded Mergansers have also been increasing; the 1,522 Hooded Mergansers was the 7^th highest total and included 161 at Linesville and 144 at Dallas Area. The 6,060 Common Mergansers was an average total for our 2^nd most common duck, with a high of 1,260 at York Springs. The 2,142 Ruddy Ducks in the recent count is an excellent total and the 2^nd highest this century, with 358 at Delaware County, 308 at Southern Bucks County, 239 at Wild Creek-Little Gap, and 235 at Erie.

Phasianidae. The 16 Ruffed Grouse at eight sites was the 2^nd lowest total across many decades, behind only the 14 in 2022. According to CBC data, 1980-1995 was a peak period for Ruffed Grouse in Pennsylvania, with a high of 314 in 1987. The lowest Ruffed Grouse mean counts per 10 party-hours have occurred during the last five years, when CBC grouse totals have also been lowest, 14-33. Ruffed Grouse is our state bird.

The 2,927 Wild Turkeys was considerably more than the 1,984 of 2023 and similar to totals of other recent years. The 86 Ring-necked Pheasants was also the 2^nd lowest total across many decades and continued a trend of being reported at fewer sites; most, if not all, were likely pen-reared birds released for hunting.

Grebes-Doves. The 230 Horned Grebes was the 4^th highest historical total, with most, 214, counted at Erie. The 20 Eurasian Collared-Doves was a new statewide high and included 16 at Chambersburg, three at Newville, and one at Bernville. The increasing numbers of the last two seasons suggests that their Great Valley population could be increasing.

Hummingbirds. Rufous Hummingbird was missed for the 4^th consecutive year; the peak period in the state CBC was 2010-2016, when it was reported annually. However, Allen’s Hummingbird at Lehigh Valley was only the 3^rd report in the Pennsylvania CBC.

Rails-Sandpipers. Four Virginia Rails were reported, including three at Elverson and one at Upper Bucks County. The most recent five years have seen the most sustained CBC reports of Virginia Rails. The 230 Sandhill Cranes was the 6^th highest count, with 221 recorded at Linesville. Two American Woodcocks were at Bethlehem-Easton.

Gulls. The 32,000 Ring-billed Gulls was a typical total. The 43,000 Herring Gulls included 40,500 at Southern Bucks County, which again led all CBC sites by a large margin. The 16 Iceland Gulls was a normal number and included 12 at Southern Bucks County and singles at Central Bucks County, Elverson, Pittsburgh, and Upper Bucks County.

The 951 Lesser Black-backed Gulls at eight sites was the 2^nd highest statewide total to the 1,257 recorded in 2022. This season’s total included 408 at Southern Bucks County, 297 at Upper Bucks County, and 220 at Central Bucks County. Southern Bucks and Upper Bucks ranked 2-3 among all CBC sites for counts of this species, while Central Bucks ranked 8^th.

Glaucous Gull was missed for the first time since 1990, although totals had fallen to single birds in the previous three years. Glaucous Gull has never been common; it has been recorded by Pennsylvania CBC sites 90 times, usually 1-3 at a time, with 11 being the most at any site. The 188 Great Black-backed Gulls was the fewest in many decades and included 163 at Southern Bucks County and 17 at Pennypack Valley.

Loons-Cormorants. Red-throated Loon was missed for the first time since 2013; usually several are reported. The two Great Cormorants, one each at Pennypack Valley and Southern Bucks County, were the fewest since 1988, when they were missed. The high year was 2007, with 76, but in the last four years, only single digits have been reported.

Herons. The 886 Great Blue Herons was an average tally, with 65 at Erie and 53 at Southern Bucks County. Three Great Egrets were reported, two at Harrisburg and one at Western Chester County. It is now been seven years without a Black-crowned Night Heron.

Vultures. Turkey Vulture numbers continued at a high level, but Black Vultures have been slightly fewer than previously in five of the last six years, similar to Pennsylvania’s Winter Raptor Survey trend.

Raptors. Three Ospreys were reported, one each at Bushy Run SP, New Bloomfield, and York Springs. This was the 5^th highest statewide total, the high being five in 1985, 2000, and 2003.

The 17 Golden Eagles tied the previous high from 2021. As usual, Golden Eagle counts were mostly seen at ridge migration sites and northern wintering areas. This included seven at Williamsport, where hawk watcher David Brown recorded all seven at the Route 15 overlook on Bald Eagle Mountain. This is a new individual site record for Pennsylvania, the previous high being four.

The 244 Northern Harriers at 61 sites was the 4^th highest total for the Pennsylvania CBC and the most in 16 years. There were 22 harriers at Clarion, 16 at Western Chester County, 11 Linesville, and 10 at Culp. The 22 harriers at Clarion ranks 15^th among Pennsylvania site totals, the high count being 50 at Hamburg in 1985.

The 169 Sharp-shinned Hawks was their lowest CBC total in 40 years. Their recent decline in the East started to become apparent around 2009. The answer to what is causing this decline is almost certainly in the boreal forest; WNV is a plausible cause if WNV is present in boreal forest mosquitoes (Bolgiano 2022), but a decline in boreal songbird populations could also explain this.

The 463 Cooper’s Hawks was consistent with an apparent plateau in Cooper’s Hawk wintering numbers. Many now appear to remain on or near their breeding territories and not migrating.

American Goshawk was missed for the 2^nd time in four years; the last previous miss was in 1965.

The 1,156 Bald Eagles was a new statewide high, exceeding the 1,092 in 2022. High counts included 105 at Southern Bucks County, 69 at Juniata County, 66 at Linesville, and 57 at Lititz.  Their numbers continue to increase, but the rate of increase may be slowing.

A total of 412 Red-shouldered Hawks were reported, 2^nd highest to the 439 in 2022, and continuing their steep increase in wintering numbers. CBC densities are highest in northwestern Pennsylvania and in the southern half of the state, particularly at southeastern sites near the state’s southern border.

Although the Red-tailed Hawk remained Pennsylvania’s most counted raptor in the CBC, the 3,088 Red-tailed Hawks continued their gradual decline from their mid-2000s peak. The 18 Rough-legged Hawks were recorded at 14 sites, with four at Clarion. This low number is now typical for the Pennsylvania CBC.

Owls. Juniata County-Lewistown reported the most owls, with 78; Upper Bucks County was second, with 67; and West Chester was third with 59.

The 17 American Barn Owls were the most recorded since 1992 and only the 4^th double-digit tally this century. The 1970s was the peak period for Barn Owls, with a high count of 45 in 1975.

The 678 Eastern Screech-Owls was an average count, but the 270 Great Horned Owls was on the low side and consistent with a slow recovery from WNV. Snowy Owl was missed for the 6^th time in the last 10 years. The 87 Barred Owls was the 4^th highest count and their trend has been increasing.  Eight Long-eared Owls were reported, the 4^th consecutive year with single digits, although detections are likely affected by eBird no longer reporting detection locations in order to protect roosts.

A highlight of this CBC was the 30 Short-eared Owls at 11 sites, tied for the 5^th highest Pennsylvania CBC total. There were nine Short-eared Owls at Clarion, four at Linesville, and three each at Bedford County, Butler County, Dallas Area, and Juniata County. A total of 41 Northern Saw-whet Owls were recorded, the 4^th highest Pennsylvania total; the high count was 62 in 2023.

Woodpeckers. This season’s woodpecker counts were not quite as high as the 2023 records for all woodpeckers except Downy Woodpecker. This season’s 878 Yellow-bellied Sapsuckers was 3^rd highest after 2023’s record 1,020. This season’s 103 Red-headed Woodpeckers was many fewer than 2023’s record 196, but still part of a modest upswing in the long-term trend. For both Red-bellied Woodpecker and Pileated Woodpecker, relatively small oscillations now appear around near all-time high numbers, apparently representing alternate-year differences in the food supply. That pattern continued this season, with this year’s counts being slightly lower than 2023’s highs.

Falcons. The 817 American Kestrels were the most in 12 years and included 60 at Juniata County, 49 at York Springs, and 45 at Bloomsburg. The 91 Merlins was a new statewide high, as their steep rise in wintering numbers continued. The 46 Peregrine Falcons was consistent with a recent plateau in totals. Merlin and Peregrine Falcon numbers increased in tandem until the last 10 years, when the rise in Peregrine Falcon numbers slowed, but there is no sign that the Merlin expansion in wintering numbers is slowing.

Flycatchers-Shrikes. The 18 Eastern Phoebes was an average number. Say’s Phoebe at Lancaster was a 10^th report for the state CBC and the third consecutive year with one recorded at the Washington Boro Water Treatment Plant along the eastern shore of the Susquehanna River. After 2023’s nine Northern Shrikes, this season’s two, at Clarion and Potter County, was more typical of the last decade.

Corvids. American Crow numbers, much affected by WNV, have not changed much in the last two decades, totaling 56,900. The 1,118 Common Ravens was a new statewide high, exceeding the 1,019 of 2023 and apparently still in a period of rapid increase.

Parids. The 3,684 Carolina Chickadees and the 8,648 Tufted Titmice are tallies partway between pre-WNV levels and the 2018 WNV-induced low, and the third consecutive year at such levels. However, the 6,200 Black-capped Chickadees remained low without any sign of a rebound.

Horned Larks-Gnatcatchers. The 5,754 Horned Larks was an average count. The 40 Rough-winged Swallows at Pennypack Valley was the same number as in 2023, continuing the observations that began there in 2005. The 2,599 Golden-crowned Kinglets was the second consecutive year with a healthy number. After a record 562 Ruby-crowned Kinglets in 2023, this season’s 440 was 4^th highest. The 166 Red-breasted Nuthatches indicated a second consecutive low year. This was the 5^th miss on Blue-gray Gnatcatcher in 10 years.

Wrens. The 500 Winter Wrens was the 3^rd highest tally, with the highest being 2023’s 704 wrens. The 6,291 Carolina Wrens was the 4^th highest tally, with two previous counts exceeding 7000 in 2019 and 2023. Marsh Wren was at Delaware County. This was the 3^rd miss of Northern House Wren in 10 years.

Mimids-Waxwings. The last four years have seen alternating high-low Gray Catbird totals; this was a low season, with 38, compared to 2023’s 3^rd-highest 104. The 2,067 Northern Mockingbirds was similar to the counts of the previous two years, representing a modest increase from the 2018 low that may have been WNV-related. Eastern Bluebird rapidly increased during the last two decades of the 1900s. Since then, their trend has shown oscillations within a relatively high population level, suggesting that harsh weather may periodically knock them back. The high total was 9,395 in 2006, with the recent count’s total being 7,347. Hermit Thrush has been found in gradually increasing numbers, with much higher counts during the last four years. The 656 Hermit Thrushes in the recent season was 3^rd highest to 2023’s high of 1,095, with a high of 47 in Huntingdon. Two common frugivores, American Robin and Cedar Waxwing, have also shown alternating high-low numbers during the last four years; this season also being a low season for them. It seems plausible that these observations might be related to the fruiting cycles of invasive bushes and vines.

House Sparrow-Pipit. The 12,440 House Sparrows were the fewest since 1958, as their gradual decline continued. The 1,024 American Pipits represented the 3^rd of four seasons with good numbers, with 427 at Bernville and 226 at Buchanan Trail.

Finches. Finch numbers were a mix of high and low counts. The winter finch forecast predicted a good movement of Purple Finches and a modest movement of Evening Grosbeaks, but no significant winter finch irruptions (Hoar 2024). A good number of Purple Finches were reported, but not many grosbeaks. The 658 Purple Finches were the most in 16 years, although not nearly as high as in many prior years. The 9,413 American Goldfinches was slightly above average.

Single-digit low counts were observed for four winter finch species: Evening Grosbeak, with three at Cowanesque Lake and two at Butler County; Common Redpoll, with eight at Hamburg and one at Central Bucks County; Red Crossbill, with three at Huntingdon and two at Dingman’s Ferry; and White-winged Crossbill, with all three at Chambersburg. The 192 Pine Siskins indicated a small siskin flight into Pennsylvania.

Calcariidae. Seven Lapland Longspurs were reported, at four southeastern sites, where most expected, plus at Northern Lycoming County and Potter County. The 160 Snow Buntings at 15 sites were the most in seven years, with 65 at Potter County, 25 at Philipsburg, and 15 each at Linesville and Northern Lycoming County.

Sparrows. Sparrow numbers were mostly average. The 2,527 American Tree Sparrows was a four-year high, but 25 years ago, it was routine to count three times as many. Fox Sparrows showed a similar high-low four-year pattern as the above-noted frugivores, while Eastern Towhees showed a similar six-year high-low pattern, with lows in the recent CBC. Vesper Sparrow was at Juniata County and Lancaster. Four Lincoln’s Sparrows were recorded, with two at Delaware County and singles at Huntingdon and Lebanon County. After 2023’s record six Clay-colored Sparrows, singles were recorded at Dallas Area and Lancaster.

Blackbirds. The 89 Eastern Meadowlark was the 3^rd consecutive season with decent numbers, with 27 at Juniata County and 21 at Gettysburg. Baltimore Oriole was at Bethlehem-Easton, Central Bucks County, and Southern Lancaster County. The 304 Rusty Blackbirds was also a decent number, with 150 at Mansfield-Wellsboro and 32 at Elverson.

Warblers. Nine warbler species were reported, an average total. This was the 4^th of 10 seasons with Black-and-white Warbler, this time at Lancaster. The 12 Orange-crowned Warblers was a new statewide CBC high, exceeding the 10 in 2022, and all but one recorded in the southeast. There were five at Southern Bucks County, three at Audubon, two at Pennypack Valley, and singles at Indiana and West Chester. Nashville Warbler at Delaware County was a 12^th report. The six Common Yellowthroats, six Palm Warblers, and 307 Yellow-rumped Warblers were average numbers. The 13 Pine Warblers was the 3^rd highest total. Bay-breasted Warbler at Dallas Area was a new species for the Pennsylvania CBC, while Prairie Warbler at Harrisburg was the 3^rd report.

References

Bolgiano, N. 2019. Evidence for West Nile Virus-Related Avian Declines in Pennsylvania. Pennsylvania Birds 33:2-11.

Bolgiano, N. 2022. Is West Nile Virus Causing Population Declines of Some North American Raptor Species? Hawk Migration Studies 47(2):17-26.

Hoar, T. 2024. Winter Finch Forecast 2024-2025. http://www.finchnetwork.org/winter-finch-forecast-2024-2025.