One and Done???
About 346 species have been recorded in Delaware County (Delco). Of this total, 32 species have been seen only once. Shall we call these 32 species the One-and-Done group? That is, these birds have been seen once, but, will they be seen again. Let’s take a look at each one and figure out if they’ll be seen again.
Black-bellied Whistling-Duck - Four birds were at the John Heinz N.W.R. 6/2/2020 visiting both Philadelphia and Delaware Cos. I’m a little surprised that it took so long for this species to make the Delco bird list. This species is annual in the mid-Atlantic and I would expect that it will probably make more appearances in Delco.
|Black-bellied Whistling Ducks 6/2/2020 John Heinz N.W.R. (Rob Fergus)|
Tundra Bean-Goose - A “Mega” find for Delco and I’m not sure if there will ever be another. The goose was present 12/16-20/2020 first at Springton Res. and then visiting Springton Lake Middle School, Springfield Country Club and some other nearby areas. It is extremely rare outside of its Siberian range. Probably one of the rarest birds to ever visit Delco.
|Tundra Bean-Goose 12/20/2020 Rolling Green Country Club (Todd Fellenbaum)|
Harlequin Duck - A female seen in southward flight along the Delaware River from Hog Island Road. Bizarre as to location and date, 7/9/2021, it may have been displaced by the recent passing of a tropical storm. Displaced, but from where, as there are very few July records except for injured birds in the mid-Atlantic.
Eared Grebe - One was on the Delaware River at Hog Island Road 3/23/07. This species should be found again maybe at Springton Res.
Allen’s Hummingbird - One of the rarer hummingbirds to visit the east in late fall and one of the most difficult to identify without in-hand measurements. An adult female was visiting a feeder in Springfield 12/9-19/2020 and was banded during its stay. After departing Springfield, this same bird, verified by recapture, was found in Philadelphia 1/6-22/2021.
Allen’s Hummingbird 12/17/2021 Springfield (Adrian Binns)
Wilson’s Plover - One was reported by two experienced birders at Springton Res. 5/10/1952. This species is extremely rare away from the immediate coast, so I’m not certain it will return to Delco.
Piping Plover - The only report is of four birds seen in the Darby Creek marshes 8/1/1950 by a single experienced birder. The date of this sighting fits within this species’s Fall Migration pattern in the mid-Atlantic, but the report of four birds raises a red flag for me that maybe it was a mis-identification.
Black-tailed Godwit - The report of this bird in the Darby Creek marshes 10/16-26/1979 attracted birders from all over the country. This is one species I expect will be found again maybe on a sandbar in the Delaware River.
South Polar Skua - Another amazing find. This bird was found and photographed by storm-watchers as it flew along the Delaware River at Hog Island Road during the passing of Hurricane Isaias 8/4/2020. Interestingly, a South Polar Skua was seen on the same day flying south of the George Washington Bridge in New York City. This species is very seldom displaced by storms which makes this sighting exceptional and possibly a One-and-Done.
|South Polar Skua 8/4/2020 along the Delaware River at Hog Island Rd., Tinicum Twp.during Hurricane Isaias (Ross Gallardy).|
Pomarine Jaeger - A group of 19 was seen flying along the Delaware River near Chester during the passing of Hurricane Sandy 10/30/2012. With the dedicated coverage along the Delaware River by storm-birders, this species will probably be seen again.
Pomarine Jaegers 10/30/2012 along the Delaware River at Chester (Jeff Davis)
Parasitic Jaeger - One along the Delaware River at Hog Island Road during Hurricane Sandy 10/30/2012. As with the previous species, it should be found again.
Black-legged Kittiwake - The only report is of an immature seen in flight by two birders in a boat on the Delaware River near Marcus Hook 12/11/1992. With dedicated late fall - early winter coverage of the Delaware River this species will probably be found again
Sabine’s Gull - Two were seen on the Delaware River at Hog Island Road 9/6/2006. Sabine’s Gull has a known overland migration and becomes widely displaced by Tropical Storms so this species should be found again. A caveat, this sighting was not storm related.
Common Gull - One photographed sitting with other gulls on at the Ridley Township Marina on Darby Creek 2/1/2020. The recent splitting of the Mew Gull complex into Short-billed Gull (US west coast) and Common Gull (Europe and Asia) added very little new identification information. This particular individual showed a dark mantle consistent with the Kamchatka race of Siberia. Carefully checking over flocks of gulls might turn up another.
|Common Gull, dark-backed gull in the back, 2/1/2020 Ridley Twp. Marina. (Samuel Neat).|
White-winged Tern - The bird, discovered during the Big Sit event at John Heinz N.W.R. 10/8/2017 spent most of its time in the Philadelphia Co. portion of the refuge. It was seen flying into the Delco portion during its stay. This bird may have been the same individual that was present near Wellsboro in northeast Pennsylvania 10-13 Aug 2017. There is a slim chance another may turn up in Delco especially during the Black Tern migration.
|White-winged Tern 10/8/2017 at John Heinz N.W.R. (Adrian Binns).|
Sandwich Tern - One was reported along the Delaware River at Hog Island Road 9/2/2006 during Hurricane Ernesto. Dedicated storm-watching may produce another.
Leach’s Storm-Petrel - Another “Mega” storm bird seen on the Delaware River at Marcus Hook 10/302012 during Hurricane Sandy. Highly unlikely, but not impossible that another will be displaced by a storm.
|Leach’s Storm-Petrel 10/30/2012 along the Delaware River near Marcus Hook (Tom Johnson).|
American White Pelican - Great find as five were seen heading south in flight over Haverford College 6/4/2019. No doubt, the same five birds were seen 6/5/2019 loafing on the Delaware River from Hog Island Road.
|American White Pelicans flying over Haverford College 6/4/2019 (Kristen Johnson)|
|American White Pelican on the Delaware River near Hog Island Rd., Tinicum Twp 6/5/2019 (Damon Orsetti)|
Scissor-tailed Flycatcher - The only report was of one seen flying in the area between the south end of the Philadelphia Airport and the Delaware River 10/26/1972. Like the Say’s Phoebe, it is rare and regular in the mid-Atlantic from late Summer through late Fall so another is due. Identification should not be a problem.
Violet-green Swallow - One seen in flight within a flock of Tree Swallows along the Delaware River at Hog Island Road 10/29/2020. Very rare in the east during Fall Migration, this might be a One-and-Done.
Cave Swallow - A bird that was present at John Heinz N.W.R. Philadelphia portion 10/31/2012 would occasionally cross into Delco. Should be looked for again in late fall as there are many records in the east from Oct-Dec. Fall birds have been determined from specimens as belonging to the southwest race Petrochelidon fulva pallida.
Golden-crowned Sparrow - One reported without details in the Delco portion of John Heinz N.W.R. 1/12/1961. Rare, but nearly annual, in the east, it should be looked for within flocks of sparrows.
Le Conte’s Sparrow - One was at the Darlington Tract 1/25-2/28/2009.There are numerous records in eastern PA in late Fall and Winter and Delco should produce another one of these skulkers.
|LeConte’s Sparrow 1/31/2009 Darlington Tract, Middletown Twp. (Adrian Binns)|
Swainson’s Warbler - One at Ridley Creek S.P. 8/14/1997 was great find. Most mid-Atlantic records are from overshoots during Spring Migration and it is very possible that is when the next will be found.
Black-throated Gray Warbler - One was observed and photographed in Little Crum Park in Swarthmore 11/29/1972. Rare and regular in late fall and winter in the mid-Atlantic states and should be found again.
|Black-throated Gray Warbler 11/29/1972 Little Crum Park, Swarthmore (Horace Alexander).|
Townsend’s Warbler - A male was seen by many at Cobbs Creek Park 11/20-21/2010. A report from Tyler Arboretum from 17 Nov 1973 could not be verified but may be a good record. Late Nov and Dec is a good time to look for this species in wooded areas.
Black-headed Grosbeak - One bird was seen at the south end of the Philadelphia Airport 5/10/1987. This species is rare and irregular in the east in both Spring and Fall with a few more records in Fall especially Nov. Most likely will be found again.
Painted Bunting - A male seen by many was visiting feeders in Broomall 3/7-20/1993. Rare and regular in the mid-Atlantic in late Fall and Winter especially at feeders. Hopefully, the next one will also be a male.
Here are a few species that have been recorded more than once, but not in a very long time (30+ years). These are all possible again so be on your toes.
Species Last Seen Years since last sighting
Dovekie 1950 72
Pine Grosbeak 1961 61
Black-backed Woodpecker 1962 60
Black Rail 1970 52
Northern Gannet 1975 47
Boreal Chickadee 1975 47
Yellow Rail 1977 45
Loggerhead Shrike 1979 43
Curlew Sandpiper 1981 41