Skuas and Jaegers

Pomarine Jaeger

Stercorarius pomarinus
The most memorable of all Pomarine Jaegers in our region undoubtedly was the adult light morph in full breeding plumage that showed up at Braddock Bay and Charlotte 19-26 June 1978 – a quite astounding time of year. What was even more astounding was that this bird proceeded to perch in places where it could be easily observed and photographed by multiple observers. (KB28: 239) Walt Listman, that consummate jaeger spotter, first noticed this “suspicious-looking, dark-headed” bird while driving to work. He called Jeanne Skelly, suggesting she might want to check it out. Skelly called Julie Claffey who then found and identified the jaeger. Skelly soon joined Claffey, and they were able to closely observe the bird “as it perched on and flew between the old pier structures” off Manitou Beach.It eventually relocated farther east off Beach Avenue, “perching and preening on the same piling for hours at a time” and providing birders “an unusual opportunity to study . . . the two twisted, rounded, almost club-shaped central tail feathers and the pale yellowish wash on the white of the neck,” John Brown reported. (BA, 21-28 June 1978) Though jaegers often “terrorize smaller gulls and terns into dropping whatever morsels of food they have been able to find or catch,” this bird “seemed to dwell in peaceful coexistence with the larger Herring gulls, sharing a concrete pillar with three or four of them” for several days. The smaller Ring-billed Gulls, he added “kept their distance.”“What, exactly, this bird has been doing posing for birdwatchers in Rochester while the rest of its tribe is attending to the perpetuation of the species on the marshy tundra above the Arctic Circle is a matter for speculation,” Brown added. “Whatever the reason, it has been a chance of a lifetime to study at close range the adult plumage of a Pomarine jaeger.” Indeed. As Chip Perrigo wrote in the Little Gull, “many of us have stood for years in painful defiance of frostbiting north winds just to glimpse this powerful pelagic predator far offshore in Lake Ontario during the mid-autumn migration. Suddenly, an adult Pomarine Jaeger plunks itself down only a few dozen yards from the beach in the middle of June! Some people just have it every easy.” (LG, July 1978)
Background
“An adult in full plumage is a magnificent sight, with its twisted central retrices often much more elongated than shown in illustrations,” notes the profile of this species in The Birds of North America series. Moreover, “Pomarine Jaegers are perhaps unique among birds in their dependence on a single species of prey (lemmings) for successful reproduction.” This bird nests in low-lying wet tundra near arctic coasts of Alaska, Canada and Russia where there are periodic irruptions of lemmings. As a result, Pomarine Jaegers breed only sporadically, and in many summers “there are apparently no such opportunities over large areas of the Arctic” and most birds leave the area almost immediately. When not breeding, these birds are found far from land, wintering on tropical and subtropical oceans where they scavenge, prey on small seabirds and steal food from other birds. “The Pomarine’s methods of parasitism are less elegant than those of the smaller jaegers; they often rely on surprise and brute force to tackle shearwaters and gulls feeding on the water rather than on acrobatics in flight.” (BNA 483: 1-2)
Local history
Eaton (1910) listed this as a rare transient visitor in Monroe County, with no record of occurrence for Livingston or Wayne.  An immature on 24 December 1964 (Foster, Maley, McNett) at Irondequoit Bay was identified “based on direct size comparison with Ring-billed Gull and on the strong, direct flight.” (KB 15: 106) It was first sighting of its species in our area in “modern history,” according to Starling. (WBR 18 January 1965) A “big flight of immatures” on Lake Ontario the following fall included three on 8 September (Listman) at Manitou, one 23 October (Genesee Ornithological Society trip) at Hamlin and one on 24 October (Kemnitzer, et al) at Sodus Bay. (KB 16:32; Bull, p.266)Reported almost annually since 1968.
Status
Monroe County annotated list (1985) described this as a regular, uncommon fall transient; a casual, very rare winter visitant; and a casual, very rare spring visitant.
Occurrence
Fall: The Monroe County annotated list (1985) indicated a range of dates from 8 August to 24 December, with a mid range of 24 September to 17 November.Of approximately 150 records in our region, most have been in September (26), October (58), and November (50).Pomarines are seen less often than Parasitics and they are not seen every year. Of jaegers that could be identified as to species at Hamlin Beach from 1976 through 1996, 102 were Pomarines compared to 398 Parasitics and one Long-tailed; no Pomarines were recorded during eight of those years. (KB47: 93)During the seven-year Hamlin Beach Lakewatch project, 75 were recorded, versus 277 Parasitics. They were almost all juvenile birds and tended to fly straight through, usually headed west. Thirty-four during the 1996 count was the highest tally for one season; there had been none the two previous years, and two years later, only two were seen. Peak period was 12 October to 2 December. (Ewald and Sherony, pp. 82-83)
Fall maxima:    6 on 16 September 1982 (Perrigo, Symonds) at Hamlin Beach SP. (KB 33:52)    5 on 19 September 1996 (Ewald, O’Hara, R. Dobson et al) at Hamlin Beach SP. (GOS, November 1996)    5 on 8 November 2005 (R. Spahn, Symonds et al) at Hamlin Beach SP. (LG, January 2006)
Winter: Most are seen in fall but can also show up later. There have been 10 records in December, and six in January:
      One on 1 January 1977 (Listman) at Braddock Bay. (LG, February 1977)      One imm. on 9 January 1983 (J. Brown, C. Cass, Davids, Perrigo, R. Spahn) at Irondequoit Bay outlet/ Charlotte. (LG, February 1983)       One 1 January 1992 (C. Cass et al) at Braddock Bay. (LG, February 1992)       One on 16 January 2002 (D. Tetlow) at Hamlin Beach. (LG, March 2002)       One 11 January 2006 (Davids, D. Tetlow) at Hamlin Beach SP. (LG, March 2006)      One 7 January 2007 (D. Tetlow) at Hamlin Beach SP. (LG, March 2007) Record late was an immature on 18 February 1998 “observed at close range” by Bill Symonds at Hamlin Beach SP. Not surprisingly, it was “in pursuit of a Ring-billed Gull.” (LG, April 1998)
Misc.
“Some seabirds are so intimidated by the presence of a jaeger that they do not even try to protect their catch,” Frank Dobson noted. In September 1985 a Pomarine seen off Hamlin took off after a Ring-billed Gull carrying a small fish. “The jaeger was still 30 feet from the gull, when the gull decided to give up, and dropped its fish. The fish didn’t fall far before the jaeger stopped its fall, swallowed it in one gulp and was back on the prowl for another victim.” (Birds, 29 September 1985)The difficulties of identifying jaegers are well-established and worth noting. During October 1983 – when a particularly good flight was observed at Hamlin Beach SP – “a jaeger well offshore was counted as a Pomarine by one group, and as a Parasitic by another group separated from the other by twenty yards and the wall of the picnic shelter,” Steve Taylor noted. (LG, November 1983) “There is no question that excellent experience has been developed by local observers in recent years in the identification of these exciting predators from the northern seas. Nonetheless, this should be some small testimony to our fallibility, and the vagaries created by snow, rain, wind, waves, distance, optics, plumage, and perhaps even the whim of the jaeger itself: does it feel like flying with deeper, more powerful wingbeats than normally; does it feel like steadily and deliberately, or erratically flying for a change; does it feel like being aggressive, or is it in the mood to cruise leisurely along the lake shore?” More than once, he added, he had seen professional, full-time birders argue over the identity of jaegers. “These birds can be difficult to differentiate, and even the most experienced of ornithologists realize that sometimes a jaeger must be called simply a jaeger.”As NYSARC noted in its 2002 annual report: “Although many birders typically identify jaegers mainly by jizz (size, shape, and flight style), David Sibley cautions, ‘The temptation to use shape and flight style for identification is almost overwhelming, but I am convinced that birders would be better off ignoring them entirely.’” (KB 54: 293)Indeed, 39 percent of jaegers could not be identified by species during the Hamlin Beach Lakewatch project (Ewald and Sherony, p. 82); nor could 136 of the 637 seen at Hamlin Beach from 1976 through 1996. (KB47: 93)

Parasitic Jaeger

Stercorarius parasiticus
There’s nothing like the sight of a jaeger to get a birder’s juices flowing. Or, on 4 October 1952, to set in motion a mad dash by car along the west lakeshore. The Parasitic was first spotted by Walt Listman, Harry Van Beurden and Tom Barry at Braddock’s Bay, flying westward out over the lake. Listman’s report on the sighting noted that the adult bird appeared to be somewhere in between intermediate and light phase, with dark upper parts and a black cap. The white belly was framed by a dark tail, breast band and sides, and there was a fair amount of white towards the tips of the wings. The distinctive pointed central tail feathers were also of fair size. The jaeger “chased a gull for a while,” Listman noted. Then it was time for the birders to chase the jaeger. “The three observers jumped into their car and raced to Shore Acres in time to see it pass by that point. They estimated the jaeger’s speed at roughly 30 m.p.h.” It is important to note that a jaeger was definitely worth the chase in those days. It was still a rarely reported species here. There was no indication that 34 would eventually be seen here in a single day!
Background
Though these birds are noted for chasing other seabirds and forcing them to disgorge their food, this is not its principal foraging tactic on its breeding grounds, which extend across the Arctic tundra of North America, Europe and Asia. They defend large territories in which they hunt for birds, mammals and eggs, and “are the most important predator of small birds in the Arctic,” according to the profile of this species for The Birds of North America series. As a result they are not as dependent as other Arctic predators, including the two other North American jaegers, on lemmings for prey. It is during migration and on their wintering grounds that they resort primarily to stealing food from other birds. During their fall migration to the southern hemisphere, they often accompany terns and thus remain near shore more often than other jaegers. There are no estimates available for this species’ population in North America. (BNA 445: 1, 20)
Local history
Eaton (1910) listed this as a rare transient in Monroe County, but gave no indication of occurrence in Livingston or Wayne counties. He listed one Monroe County record, that of George Guelf on the lake shore, 10 November 1897. (Eaton I: county charts, II: 117)There were apparently no other sightings until 23 September 1934, when an adult was seen around the Summerville Pier until 3 October, Edson reported. (WBR, 12 December 1960) However, Horsey does not indicate any sightings of this species in his listing of birds seen at Rochester and Monroe County from 1913 to 1936.One reported by Laura Moon, albeit tentatively, 1 October 1950 “chasing the gulls over the piers at Charlotte” was only the seventh record for Monroe County, Edson noted. (WBR, 9 October 1950) It apparently stayed along the lakeshore until the 24th; on the 22nd of that month another injured bird was picked up by the Kemnitzers on the shore at Durand-Eastman Park. (GOS, September/December 1950)There were three records that fall, another in 1952, two more in 1953, another in 1956, and then an unprecedented of influx of eight between 14 September and 24 November 1957, all individual birds recorded by Walt Listman at Manitou. (KB 7: 120)Listman was the undisputed champion at spotting these birds. It helped that he lived right at the lakeshore at Manitou Beach. However, he was also keenly aware of how weather could influence their appearances. While eating breakfast on 20 September 1962, for example, he glanced at the weather map in the newspaper, and noticed that a cold front and low pressure center had passed over James Bay a day or two before.He immediately picked up his binoculars to scan the lake outside his Manitou Beach home and within minutes saw a Parasitic Jaeger fly by. (BA, 27 September 1962)So Listman was definitely one of those “keen observers on the watch for this species” that Bull credited for the beginning of regular fall sightings along Lake Ontario during this time. (Bull, p. 266)  Increased lake coverage, better optics and increased observer experience have all combined to produce tallies in recent years that would have astounded even Listman. This is now a regular late summer/fall/early winter visitor, though numbers fluctuate dramatically from year to year.
Status
Monroe County annotated list (1985) described this as a regular, uncommon to fairly common fall transient and a casual, very rare spring visitant (one record: 20 May 1947).
Occurrence
This remains the most common jaeger tallied here. Of jaegers identified to species at Hamlin Beach SP from 1976-96, 398 were parasitics compared to 102 pomarines. (KB 47: 93)
Fall: The Monroe County annotated list (1985) indicated a range of dates from 23 August to 3 December, with a mid range of 23 September to 3 November.      Subsequently, one on 6 August 2002 (Symonds) at Hamlin Beach set a new record early date. (GNR) “Until relatively recent years, the gull-like jaegers of the northern oceans were considered extremely rare visitors to the shores of Lake Onatrio, but with the improvement in identification techniques and a great increase in the number of competent observers, they are now regarded as regular fall visitors and migrants,” John Brown noted. (BA, 23 September 1982) Our first August record came when Listman saw one “on a northeast wind” on 24 August 1974 at Carlton. (KB 25:36) “Until recent years,” Frank Dobson added in 1985, “area birders would wait until late September before heading for Lake Ontario’s shores to look for jaegers. Ideal conditions were thought to be strong northerly winds, waves rolling six to eight feet, white caps to the horizon and a chill in the air that would bring tears to the eyes.” But “early and consistent lake watching” revealed that these birds can also show up “on a warm, pleasant, windless day in late August.” (Birds, 29 September 1985) Indeed, some extraordinary tallies are possible even in August (see maxima below). Twelve of the 16 birds tallied at Hamlin Beach SP in late August of 1985 (Symonds et al) were seen on the 27th alone. (LG, August/September 1985) Forty were tallied there (Symonds, D. Tetlow) from 17 to 31 August 2004, including a record 34 on the 29th or 30th. (LG, October 2004) However, in analyzing the data from the Hamlin Beach Lakewatch project, Ewald and Sherony found that the peak period is 22 September to 27 October. Parasitic Jaegers typically arrive one to two days after a cold front passes through. Most are juveniles, tending to move east early in the season, west in the later stages. “They usually pursue Ring-billed Gulls but there is one observation of a Parasitic Jaeger chasing a Bonaparte’s Gull.” (Ewald and Sherony, p. 84)Numbers can vary dramatically from year to year. 277 were recorded during the seven-year Hamlin Beach Lakewatch, with 126 the peak tally in 1996, after only five in 1995. (Ewald and Sherony, p. 85)“It appears that when the weather is dominated by strong northwest or west winds, high counts occur in the eastern side of Lake Ontario, and those years when northeast winds dominate, the higher jaeger counts occur on the west side of the lake,” Dominic Sherony wrote in 1996. “Since lake observations are limited to a maximum of about one-half mile viewing distance, it has been the belief of most observers that there are more jaegers on Lake Ontario than are being seen. Indeed, many of the birds are seen at long distance and cannot be separated by species.” (KB 47: 91)
Maxima:     11 on 23 August 1984 (Symonds) Hamlin Beach SP. (LG, October 1984)    12 on 27 August 1985 (Symonds) at Hamlin Beach SP. (LG, August/September 1985)    34 on 29 or 30 August 2004 (D. Tetlow, Symonds) at Hamlin Beach SP. (LG, October 2004)    11 on 1 September 1983 (Davids) Hamlin Beach SP. (GOS, November 1983)    13 on 28 September 2001 (D. Tetlow) at Hamlin Beach SP. (LG, November 2001)    13 on 10 September 1996 (C. Cass, K. Fox) at Hamlin Beach SP. (Little Gull, October 1996)     10 on 27 October 2002 (J. Skelly, S. Taylor, Symonds) at Hamlin Beach SP. (LG, December 2002)   One on 3 December 1960 (Listman) was at Manitou (KB11: 45), then more than 30 years elapsed before another December sighting occurred, on 4 December 1992 (Symonds) at Hamlin Beach SP. (LG, January 1993) Since then systematic lake coverage has turned up nine more “winter” birds, including four from 3-18 December 1997 at Hamlin Beach SP (KB 48:144) and record late individuals there (D. Tetlow, Symonds, R. Spahn) on 2 and 3 January 2002. (LG, March 2002)
Spring: The Monroe County annotated list indicates one on 20 May 1947.
Misc.
Bob Spahn reported an “interesting keystone cops chase sequence” involving an adult off Hamlin Beach SP about 11:20 a.m. on 16 October 2007. “First it rose to attack a Ring-billed Gull; when it broke off, the Ring-billed Gull turned and chased it, but was easily eluded; then as the jaeger started to drift away, a Double-crested Cormorant jumped off the water and ‘shot’ up at it, again easily eluded after which the jaeger flipped over and dove on the back of the cormorant’s neck. The jaeger finally drifted out a bit and sat on the water too far out to be found in the chop and swells. Haven’t seen a cormorant-jaeger interaction before.” (Posting at Genesee Birding at Birdsonthe.Net)

Long-tailed Jaeger

Stercorarius longicaudus
Dave Tetlow has been involved in several of the sightings of this species, so he was a logical choice to ask: If someone is at Hamlin Beach SP in late summer, what should they be looking for? “It’s a slight bird, with a more buoyant, tern-like flight” than Parasitic or Pomarine, Tetlow noted. “And they’re always a lighter, sandier color. It’s always possible you could get a dark morph, but to date we haven’t had one.”Most have been young birds, and some have been relatively close to shore. “But at this time of year you’re always dealing with haze and shimmer,” Tetlow added. One other clue for trying to determine if you are indeed seeing the jaeger that is least often recorded here: These birds are not nearly as aggressive as Parasitics and Pomarines towards gulls and other birds. “Usually you don’t see any chases.”
Background
The smallest and most graceful of the jaegers is also the most widely distributed and abundant on its breeding grounds in the Arctic Tundra of Alaska, Canada, Europe and Asia. During the breeding season it feeds primarily on lemmings and voles, often hovering like kestrels (and unlike other jaegers) or watching from a perch. Unlike other predators of the far north, it is not unduly affected by periodic crashes in these rodents’ populations. It “simply does not breed and returns to sea,” notes the profile of this species in The Birds of North America series. It is highly pelagic during migration and winter, and is rarely spotted inland south of Canada. Though “inland records have suggested migration over interior,” difficulties in separating jaegers makes it difficult to document to what extent this actually occurs. Large numbers of wintering birds of all ages are seen off southeast South America; similar concentrations have not been located in the Pacific. Less likely than other jaegers to harass terns and gulls. (BNA 365: 1-2, 5-7)
Local history
Eaton (1910) listed this as a rare transient for Monroe County, apparently basing this on the notes of David Bruce of Brockport. No specific occurrences cited. (Eaton I:118, county charts) This species is not even listed in Beardslee and Mitchell.
Status
Monroe County annotated list (1985) described this as a casual, very rare visitant. At that time there was only one record. However, the increase in sightings in recent years suggests this species is a regular but very rare late summer transient.
Occurrence
The jaeger least often seen here. “Long-tailed jaegers are rarely reported on Lake Ontario, but there have been more reports in recent years,” NYSARC noted in 2003 (KB53: 288-289), “mostly because observers are watching the lake earlier in the fall.” Regular, systematic lake coverage at that time of year is now providing a truer picture of its occurrence. 1. One “well-studied offshore bird” 31 August 1984 (Symonds) Hamlin Beach SP. (KB 34:243) 2. One adult 18 August 1999 (Symonds, D. Tetlow) Hamlin Beach SP (KB 49:333) “seen at a great distance, but was well-documented” by Dave Tetlow. (LG Oct 1999) This bird landed in the water. (Ewald and Sherony, p. 82) 3. One adult 29 August 1999 (Symonds, D. Tetlow, Cass) Hamlin Beach SP (KB49:333), was also seen at a distance, “but was well observed for over five minutes” (LG Oct 1999) before it “spiraled up out of sight.” (Ewald and Sherony, p. 82) Not accepted by NYSARC. (KB 52:313) 4. One 5 September 2000 (Sherony, J. Skelly, Symonds) Hamlin Beach SP Hamlin Beach SP. (LG, November 2000) 5. One 26 August 2001 (Symonds, Taylor) Braddock Bay. (KB 51:785) 6. Two 27 August 2001 (D. Tetlow, Davids) Hamlin Beach SP. (KB 51:785) 7. One adult 29 August 2001 (Symonds) Hamlin Beach SP. (KB 51:785) Though observed by two people for only “a very brief time as a fly-by,” NYSARC noted, “this bird's grayish head contrasting with the darker body was an important feature that weighed heavily with the committee's decision to accept this submission.” (KB 53: 288-289) 8. One subadult 10 September 2001 (D. Tetlow, Bounds) Hamlin Beach SP. (KB 52:59-60) 9. One adult 18 August 2002 (Davids, Symonds, D. Tetlow) Hamlin Beach SP, “nearly annual when daily lakewatch active.” (KB 52:347, 350) 10. One immature 2 September 2004 (D. Tetlow) Hamlin Beach SP. (KB 55:51) 11. One immature 16 October 2005 (D. Tetlow) Hamlin Beach SP. (LG December 2005) 12. An immature 5 September 2006 (Symonds) at Hamlin Beach. (LG, October 2006) 13. An immature 6 September 2006 (R. Spahn) at Hamlin Beach. (LG, October 2006) 14. An adult 21 August 2007 (Symonds) Hamlin Beach SP. (LG, October 2007) 15. Two on 26 August 2007 (Symonds, D. Tetlow) Hamlin Beach SP. (LG, October 2007) 16. One on 10 September 2007 (D. Tetlow) Hamlin Beach SP. (LG, November 2007)

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