The November 1999 Cave Swallow Invasion in Ontario and Northeastern North America
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13 The November 1999 Cave Swallow Invasion in Ontario and Northeastern North America Bob Curry and Kevin A. McLaughlin THE DISCOVERY square-ended tails, he then realized At around 1215h EST, on Tuesday, 2 that the birds had orange rumps, vis November 1999, KM drove into the ible as they did a few ground level Point Pelee National Park Visitor circuits of the parking lot. KM was Centre parking lot. It had been a enthused, not being able to remem rather slow morning of"car birding" ber having seen even one Cliff in a steady rain, with the only high Swallow (Petroehelidon pyrrhonota) light being a Merlin (Falco eolum in Ontario as late as October, let barius) which landed in one of the alone five in early November. tall trees at the small parking lot on Something was wrong, however, for the west side of the tip. In fact, the a brief look up through the rain had most eventful item was the drastic revealed what appeared to be a pale change in the weather. The previous throat on one or two ofthe birds. No several days had been balmy with sooner had KM exclaimed to him southwest winds, conditions so self "Are these Cave Swallows?" benign that KM had seen nine than the birds disappeared some species of butterflies on Monday where behind the Visitor Centre. morning, 1 November, under sunny After failing to re-find the birds, skies and a temperature of 16-18° C. KM decided to report the five as Cloud cover had increased by "Petroehelidon" swallows in the Monday afternoon, followed by rain sightings book in the Centre, at the overnight, with the wind shifting to same time telling two staff members northeast, resulting in a drop in tem of his suspicions on the identity. He perature to around 4° C. then returned to the parking lot to Parking the car, KM immedi await the birds' return, seeking shel ately noticed a group of five chunky ter in one of the transit cars which swallows flying low, approaching the had been parked in the lot. After an car from the vicinity of the Visitor hour and a half of fruitless watching, Centre. Little could be seen on the he drove north through the park, birds through the rain-splattered checking the Delaurier parking area windshield. Thinking that they and Northwest Beach, again with no were probably Tree Swallows success. Deciding around 1500h to (Taehycineta bieolor), KM got out check the West Beach parking lot, of the car for a better look. Noting he found, towards the south end, the off-white underparts and five swallows foraging. The birds VOLUME 18 NUMBER 1 14 flew past the car, quickly going happily returned to the Visitor inside one of the three picnic shel Centre, whereupon he contacted ters bordering the parking lot, as if Tom Hince in Wheatley, who alerted looking for a roosting site. They ONTBIRDS (the Internet bird then disappeared, flying south, still sightings listserve sponsored by the not affording KM an identity Ontario Field Ornithologists). clinching view. Events proceeded quickly over the On Wednesday morning, 3 next several days, with Cave November, KM spent several hours Swallows being found again at Point on the sheltered east side of the tip, Pelee and elsewhere along the north watching for migrants. The rain had shore of Lake Erie at Erieau, Port ended overnight and the wind had Burwell, Long Point and beyond. shifted to northwest, blowing at near gale force, with the temperature DESCRIPTION OF POINT around freezing. During this time, he PELEE BIRDS saw several groups of swallows fly The field marks noted below are ing south off the Tip, adding up to at based on observations by KM on 2 least 25 birds. All of the birds were to 5 November at Point Pelee. The "Petrochelidons", and those that study obtained at the south end of could be seen in brief frontal views, the Sanctuary Pond near the park appeared to have pale throats. Once entrance on 4 November involved a again, however, totally conclusive bird flying in the company of sever views could not be realized. al Tree Swallows. KM returned to the east side of the tip around 1400h, and at once • Broad winged, husky swallow, found a swallow foraging low over slightly smaller than Tree Swallow. the water very close to shore. Finally, • Pale orange throat and auriculars, the hoped for conditions were real which colour extended around ized. The bird flew methodically the side of the head to the nape, about, only inches above the surface, and blended vaguely into the and approached to within a few feet. white breast. All frustrations vanished, as it was • Chestnut patch on the forecrown, definitely a Cave Swallow (P. fulva)! recalling Barn Swallow (Hirundo Moments later, two more Cave rustica). This patch was slightly Swallows joined this bird, permitting contrasting with the slate colour leisurely studies. KM now realized of the top of the head, and con that he was witnessing an unprece trasting more so with the pale dented Ontario invasion of this orange throat. species and that all the birds seen • Dark line between the dark eye Wednesday morning and Tuesday and black bill. afternoon were Cave Swallows. He • Upperparts with broad dark gray ONTARIO BIRDS APRIL 2000 15 wings, slate-coloured back with observation of 25 birds leaving the several (3 or 4) white lines down Tip in the morning by KM, followed the centre. by another three in the afternoon, • Dull orange rump patch, perhaps Tom Hince found two going to roost best described as "burnt" orange, at Sturgeon Creek and another two which seemed a bit darker orange in an old Barn Swallow nest at the than the throat. Visitor Centre. Away from Point • Underparts more off-white than Pelee, Jim Burk flushed three Cave Tree Swallow, not gleaming white, Swallows from his garage at Erie with a gray wash on the sides of Beach about 6 km west of Erieau in the breast and belly. Kent County. Also on this date, four • Tail dark gray or slate, at all times birds reported initially as Cliff appearing essentially unforked or Swallows at Long Point Tip were square-tipped. seen the next day and subsequently confirmed as Cave Swallows. THE ONTARIO STORY Subsequent to the discovery and 4 November: It is significant that all confirmation at Point Pelee, the but one Cave Swallow observation next four days (Wednesday, 3 from Ontario was from the north November to Saturday, 6 shore of Lake Erie. Long Point was November) produced multiple the epicentre. After information sightings by many fortunate birders. about birds roosting under eaves in In fact, so many observers were Barn Swallow nests was posted, involved that we have decided to Long Point Bird Observatory staff include names only for initial obser at the Tip found three roosting in vations at a location and for the nests at their cottage on Thursday later observations, after the num morning, one of which was cap bers of birds dropped off. Most of tured, banded and photographed the information comes from ONT (Christine Jamieson, pers. comm.). BIRDS. It is pleasing to note that See Figures 1 and 2. Over the virtually all sightings have been course of the day, observers totalled supported by documentation sub 13 at the Tip and 25 at Old Cut. mitted to the Ontario Bird Records Inasmuch as the birds at Old Cut Committee (OBRC), and that were flying west and foraging as OBRC has accepted these records they went, it is impossible to say (Kayo Roy, pers. comm.). how many left the Long Point peninsula and how many of those 3 November: There may have been seen the next day were new. as many as 32 birds at Point Pelee on At Point Pelee, the two birds in Wednesday (Alan Wormington, the nest at the Visitor Centre were pers. comm). In addition to the watched from dawn until one flew VOLUME 18 NUMBER 1 16 Figure 1: Juvenile Cave Swallow (P! pallida), Long Point Tip, 4 November 1999. New remiges are Pi to P6, as well as Sl and S2 and some tertials, indicat ing that this bird was farther into first prebasic molt than the Point Pelee bird. Photo by Christine Jamieson. out. Subsequently, the other was were enjoyed by a host of observers, picked up in a very weakened con as the birds foraged actively in the dition (BC) and died (Figure 3). warm sun, mostly between the Elsewhere at Point Pelee, three oth Provincial Park on the east and the ers were seen foraging over Causeway on the west. Another Sanctuary Pond for most of the day three at Turkey Point (Jerry (Matt Baker et al.). Guenther, ONTBIRDS) followed At Erieau, six birds were seen in the shoreline in an easterly direction the pier area (Steve Charbonneau, towards Port Dover. This observa ONTBIRDS) until almost dusk and tion indicates that all birds did not almost certainly must have roosted automatically fly west and further there. Whether these included the confounds attempts to estimate total three at Erie Beach the day previous numbers. This is the farthest east is impossible to say, but likely those location in Ontario, except for a were different birds. report of a Cliff Swallow just west of Port Dover by a casual observer 5 November: Approximately 24 were (fide John Olmsted). at Long Point; eight at the Tip and A day of diligent searching by about 16 near the base. These latter seven observers was rewarded with ONTARIO BIRDS APRIL 2000 17 Figure 2: Long Point Tip bird.