Wednesday, November 17, 2010

The Appledore Gull and the Expansion of Lesser Black-backed Gull in North America

On February 22/2009 I was photographing gulls at Daytona Sores in Florida. There was a nice selection of LBB Gulls of all age classes. Just before leaving I cam across a very nice adult LBB Gull with bands on both legs.


Banded LBB Gull-Daytona Shores, Florida

At the time I did not recognize these as "federal bands" and assumed the bird was banded either in Greenland, Iceland or the Old World. I was excited about potentially documenting the origin of at least some of the birds on the east coast. I made several enquiries but couldn't track down the origin of the bird. 

Much later while doing some research on the expansion of LBB Gull in North America I was reviewing the two breeding records of this species in North America and came across the following blog.

Banded LBB Gull-Daytona Shores, Florida

So it turns out that this banded adult LBB Gull has been breeding with a Herring Gull since the summer of 2007 on Appledore Island off the coast of New Hampshire. This event was well described in "Breeding by a Lesser Black-backed Gull (Larus fuscus) on the Atlantic Coast of North America" in American Birds Vol. 61 p.546-548.

This bird was discovered subsequently at Daytona Shores, by several birders including Michael Brothers and Alvaro Jarmillo in Jan.,2009. This was prior to my  documentation of the bird in late February and the bird apparently wintered  in that general vicinity between Jan-March, 2009.

The bird has returned to Appledore Island for at least four summers and has produced several hybrid young. One of these was documented on the coast of Alabama by Marshal Iliff on October 10/2010. This bird had been banded during the summer of 2009.  Pictures of this bird and more on Appledore gulls can be found at the following link.



A second cycle offspring of the Appledore birds was seen by Blair Nikula at Cape Cod and subsequently at Cocoa Beach Landfill, Florida by Mitchell Harris.




Second cycle LBB x Herring Gull at Cape Cod,MA  Dec., 2009-Blair Nikula

Although suspected LBB X Herring hybrids are seen not to infrequently on the eastern seaboard and Great Lakes I believe these birds are unique in having a known provenance.

The following map shows the sightings of the adult LBB Gull that has bred at Appledore (pink pushpin) as well as records of the offspring sightings (green pushpins) as well as the location of Appledore Island (yellow pushpin).


Appledore Gull Sightings
Appeldore Island, Lesser Black-backed -Herring Gull Breeding Site-yellow
Adult LBB Gull- pink
Offspring LBB X Herring Gull-green

The other breeding record of LBB Gull on the continent is also with a Herring Gull at Juneau, Alaska in June/1993.Given the number of juvenile LBB Gulls as well as probable LBB X Herring hybrids seen throughout the continent it is thought other breeding sights undoubtedly exist in North America.

Traditionally LBB Gulls nested exclusively in northern and western Europe. In the later half of the last century the breeding range expanded dramatically to the north west breeding was extended from the British Isle to Iceland and by1990 they had started breeding in Greenland. 

In a 2008 paper by Boertland, "The Lesser Black-backed Gull, Larus fuscus, in Greenland"- Arctic,Vol.61p.129-133- he states "today lesser black-backed gulls breed abundantly in Southwest Greenland." They conservatively estimated 700 pairs in 2003. These sites are actually closer to the Great Lakes and eastern seaboard than many of the high arctic sites of Glaucous, Kumlien's and Thayer's Gulls.


Comparison between LBB Gull breeding sites and Glaucous Gull breeding site on Bylot Island, Nunavut

The distance from the Greenland breeding colonies to Sault Ste. Marie is about 2800 km which is about 200km closer than the Bylot Island site were my recent banded Glaucous Gull originated. So it seems quite reasonable that the birds on the Great Lakes could well originate from the Greenland colonies.



Juvenile LBB Gull Sault Ste. Marie,ON- Sept. 19/10

Boertland observed recently fledged juveniles on July 28th,2006. The latest sighting of a juvenile in Greenland is September 10. Egg laying apparently begins in late May and may continue until late June. He quotes a brooding period of 25 days and a fledgling period of 35 days leaving lots of time for juveniles to reach the Great Lakes by mid-September.

Boertland discusses that LBB Gull was considered a rare vagrant in West Greenland until the mid 70's with only six Greenland records prior to 1984. This coincides with the period of increasing records in eastern North America. I have assumed that this was directly related to the increased number of birds breeding in Iceland..


A relatively light mantled adult LBB Gull typical of the subsp. L.f graselli that breeds in Greenland


I tried to get information on LBB Gull breeding in Iceland and found an interesting website called Tracking Larus fuscus. They have been color ringing LBB Gulls in Iceland since 1996 and it has been coordinated by Gunnar Thor Hallgrimson since 2007. They have a page on the website with pictures of many of their wintering ringed birds. 


Of the 31 birds pictured none were photographed in North America. Most of the birds appeared to be wintering in Spain and Portugal.  Are we missing these birds or are people seeing them and the information is not getting back to the banders? If anyone has seen a banded LBB Gull with  a blue band with black or white alphanumeric codes I would be very keen on hearing about it as would the Iceland ringing team.


Keep your eyes peeled for these blue leg bands on LBB Gulls
report one here:





Y522 was ringed as a chick at Gardaholt, SW-Iceland, 4 August 2004. The picture is taken on 21 November 2004 at Foz Harbour, Foz, Lugo, NW Spain.
© Antonio Gutierrez




YA87 was ringed as an adult at Sandgerði, Reykjanes Peninsula, SW-Iceland, on 27 August 2007 by Gunnar Thor Hallgrimson. The picture is taken 29 February 2008 at Cedeira Beach, Cedeira, A Coruña, Spain.
© Antonio Gutierrez



Y367 was ringed as a chick at Garðaholt, Garðabær, SW-Iceland, on 23 July 1999 by Hallgrimur Gunnarsson. The picture is taken 27 February 2008 at Pantín beach, Valdoviño, A Coruña, NW Spain.
© Antonio Gutierrez


Despite the lack of recoveries  it seems likely that some of the Iceland birds winter in North America. It would be nice to verify this by documenting some of these ringed LBB Gulls from Iceland.

Iceland was certainly the stepping stone to colonization of Greenland and likely further colonization of North America mostly likely in Labrador and/or Newfoundland (ala Black-headed Gull).



Adult LBB Gull wintering in Newfoundland a likely spot for colonization

The first confirmed record of LBB Gull in North America was in New Jersey in 1934. There was only occasional records until the mid 70s when they became increasingly common both on the eastern seabord as well as the Great Lakes. The first LBB Gull for Ontario was found by Ron Pittaway and Roger Foxall in Nepean in Nov.,1971. It was confirmed at the time by Earl Godfrey but somehow never made it into the official record. The official first record was seen shortly after the Nepean bird in Hamilton. There is a documented record from March 14,1949 from Buffalo Harbor, NY. (pers comm Ron Pittaway).


 Adult LBB Gull in flight  at the St. John's Landfill, Newfoundland.

Since the initial wave of sightings in the mid 70s LBB Gull has been seen in all of the eastern states and provinces with  West Virginia being the last state in the east to record this species. Arizona, New Mexico and Utah all have recent records. It is relatively common wintering coastal bird in Texas (personal observation) and occasionally inland as far as Amarillo (pers comm Barret Pierce). I would be interested to hear if any states in the west are lacking this species on their state list.

On a cruise to the Carribean in early 2010 I was  mildly surprised to find LBB Gull a common bird in the Bahamas at least on Nassau. Although not as apparent in the Lesser Antilles I saw at least 2 adults on St. Martin.


Multiple LBB Gulls wintering in Nassau

In Raffaeles'"A Guide to the Birds of the West Indies" published in 1998 this species was considered very rare in the West Indies. Records had been documented for most of the major islands. Clearly things have changed in the last decade.


As many as 456 LBB Gulls have been seen at one spot in North America at Lake Nockamixon, PA in March,2007.  Boertman, 2008 theorized the recent range expansion of LBB Gull is secondary to "increased food resources (fishery discards,garbage,etc.)". In regards to the colonization of SW Greenland he states, "colonization did not take place until there was a sufficiently large surplus population from Iceland and northwest Europe to support a founder population". Along with the expansion across the North Atlantic the range of this species has expanded southward into France and the Iberian Peninsula with breeding as far south as the Canary Islands.


Adult Lesser Black-backed Gull possibly winging its way back to Greenland

My next post will be devoted to the "trickier than you'd think" identification of second winter white-wing gulls, using an interesting gull photographed by Peder Svingen at Wisconsin Point and submitted to ID Frontiers by Ryan Brady. This bird was variously thought to be potentially everything from a Kumlien's to Thayer's to Kumlien's x Thayer's to a Nelson's Gull. Should make for an interesting dissection.

Kirk Zufelt
zufelt_k@shaw.ca







Thursday, November 11, 2010

Banded Glaucous Gull from Nunavat

I was very pleased to discover the origin of my banded adult Glaucous Gull. Thanks to some help from Joe Kaplan who recognized the "federal band" and some word of mouth via the internet I received an E-mail form Louise Laurin from the Canadian Wildlife Service letting me know the bird had been banded at South Plain, Bylot Island , Nunavut.


Adult Glaucous Gull from Nunavut

Subsequently I was thrilled to hear from the bander- Jean-Francois Therrien who added that "I marked this Glaucous Gull  as a fledlging on Bylot Island, in August of 2007". Thus this is a 4th year bird and its first year in fully adult plumage. The distance from Bylot Island to Sault Ste. Marie is a mere 3,005 km  as the gull flies,


Bylot Island, Nunavut to Sault Ste. Marie, Ontario as the gull flies

I am reasonably well travelled especially in North America but I must admit I have never heard of Bylot Island. Well it is off the north-east corner of Baffin Island in Canadas newest province Nunavut.
It is a large island in fact the 72nd largest island in the world. At 11,067 square kilometers its just a touch smaller than Jamaica. No Sandals resort however.

Bylot Island, Nunavut, Canada

It was discovered by the arctic explore Robert Bylot in 1616 during his search for the North West Passage. Apparently it has a very rugged coast with a mountainous interior and many glaciers.


Sattelite image of Bylot Island showing its multiple glaciers

Bylot Island was designated a Migratory Bird Sanctuary in 1965. It has some fantastic sea cliffs that provide nesting locations for a large number of seabirds including 320,000 Thick-billed Murres and 50,000 Black-legged Kittiwakes (I wonder if this is the origin of the Kittiwakes seen each fall on Lake superior).



Thick-billed Murre-St.Paul, Alaska




Black-legged Kittiwake - St. Paul, Alaska

Apparently there is a large plain in the southwest of the island that holds about 75,000 breeding Snow Geese and of course Glaucous Gulls. In 1999 Sirmilink National Park was incorporated an included Bylot Isaland and some surrounding areas. Along with over 50 species of breeding birds the island houses at least 150 Polar Bears.

Mt. Thule on Bylot Island by Group of Seven artist Lawren Harris

Lawren Harris painted Mt. Thule on Bylot Island in 1930. It isn't clear to me whether he visited the area or not. Interestingly Lawren Harris and his associates in the Group of Seven arguably the most well known and quintessential Canadian artists really made their names painting landscapes largely in Algoma the area surrounding Sault Ste. Marie. 

Getting back to gulls the LBB Gull below was photographed at Daytona Shores on Feb. 22th , 2009. It took me about a year and a half to find out its history. The story is quite remarkable and I will share it with you on my next post.



Banded celebrity adult Lesser Black-backed Gull - Daytona Shores, Florida

The local gull situation is slower than expected. The Vega Gull was never seen again despite extensive searching. Currently there are several first year and at least one adult Great Black-backed Gull around with several juveniles and at least one second winter and one adult Thayer's Gulls. The numbers of Kumlien's Gulls is low with just one juvenile bird that I have noted. Despite a few early Glaucous Gulls there are none around currently. Apparently there is lots of open water up in James and Hudson's Bay (pers comm Alan Wormington) and this might be responsible for the relatively poor movement so far of arctic gulls.

Kirk Zufelt
zufelt_k@shaw.ca




Sunday, October 31, 2010

Adult Vega Gull in Sault Ste.Marie,ON

I could have titled this "Possible Vega Gull" or "Vega-like Gull" but I opted not to hedge. This bird seems to meet all criteria for an adult Vega Gull. For those who aren't obsessed with Larusology you might be asking -What is a Vega Gull?

According to the AOU a Vega Gull  is Larus argentatus vegae the east Asian-western Alaska subspecies of the Herring Gull. Olsen and Larsson consider it a separate species L. vegae closer to Slaty-backed than Herring Gull. Ujihara the Japanese gull expert also considers it a species. Howell and Dunn describe the differing viewpoints and go on to say "American Herring Gull, European Herring Gull and Vega Gull are best treated as distinct species,".

Today at the landfill I noted a darkish mantled gull.

Adult Darkish Mantled Gull- Sault Ste. Marie

Although the mantle was clearly darker than the Herrings it clearly wasn't dark enough to be a Lesser Black-backed or darker gull. This immediately rules out Slaty-backed and Great Black-backed (GBBG)which this bird clearly isn't. The bright pink legs and mantle shade rules out Lesser Black-backed.

At first I was thinking Herring x Greater Black-backed hybrid. However on prolonged observation of the bird many things didn't seem to fit with that identification. First off the birds structure seemed very consistent with Herring Gull with no GBBG traits.

                 Adult Herring Gull                 Adult Vega Gull - Sault Ste. Marie

                      Adult Vega Gull           Adult Herring Gull  - Sault Ste. Marie

Overall in size the bird was similar to the surrounding Herring Gulls. It was larger than many but smaller than about 30% of the nearby Herring Gulls (observation at the time). The head shape was consistent with Herring Gull as was the bill size.

I noted what appeared to be a darkish eye.

Adult Vega Gull - Sault Ste. Marie

On very close inspection through the scope the eye was brownish yellow and the the orbital ring was distinctly reddish in colour. 

Adult Vega Gull - Sault Ste. Marie - close-up

If you go to your Sibley-Guide to Birds there is a very nice illustration of a adult Vega Gull on page 217 showing the orange-red orbital ring and the brownish yellow iris. The American Herring usually has a much paler iris and a yellowish-orange orbital ring.

Adult Herring Gull-head close-up

Many GBBG and LBBG hybrids could potentially have a reddish orbital ring as well. I really needed to get some open wing shots to look for the other differentiating features of Vega Gull- 1. a very broad white trailing edge 2. white tongue tips on P6-8. Both of these features are reminiscent of Slaty-backed Gull.

Well after about an hour I finally got a decent series of open wing shots.

Adult Vega Gull - Sault Ste. Marie

Note on the above bird the very wide white trailing edge as well as the white tongue tips on P6-8. (Tongues are the non black areas of the primaries sticking out into the black like a tongue.


Adult Vega Gull - Sault Ste. Marie -showing white tongue tips
Peter Adriaens pointed out that I had this primary incorrectly labelled P6. I had counted back from P10 and failed to note P7 is missing. I have corrected this on the current picture.This is actually even more supportive of Vega as most commonly a complete band is present across P5-although this is variable.-KZ

Adult Vega Gull - Sault Ste. Marie -showing white tongue tips

 The primary pattern on my bird is very similar to the Vega Gull wingtip pattern #2 shown in Olsen and Larrson pg. 28. None of the American Herring Gull patterns approach this especially the amount of white on the tongue-tip of P6.

I would like to thank Japanese gullmasters  Osao and Michiaki Ujihara for allowing me to use the following illustrative pictures from there excellent website. The following pictures were taken in late Oct. in Japan.



Adult Vega Gull -Japan-Oct.25/06-  Osao and Michiaki Ujihara

Note the similar stage of moult to my bird with mostly old primaries and missing coverts. According to Olsen and Larsson the outer primaries moult from late Nov. to Feb. Howell and Dunn confirm that Vega Gull under goes "a relatively late PB moult". In Ujihara's pictures of over 25 adult Vega Gulls on Oct. 25/06 all had retained some old primaries. In my bird P8-10 are old. Looking at hundreds of adult Herring Gulls today virtually none had retained old primaries and most had P9-10 almost completely grown in.

Adult Vega Gull-Japan -Oct.25/06-  Osao and Michiaki Ujihara

The above Vega Gull taken at a near identical time of year shows a near identical moult timing and wingtip pattern.




Adult Vega Gulls-Japan -Oct.25/06-  Osao and Michiaki Ujihara

The above photos show several Vega Gulls in late Oct all with retained old primaries and several with still all white heads like my bird. 

Chris Gibbins authored a study- "Identification of Adult Vega Gull: Field Observations from Japan". This was done in February so some observations such as head streaking could not be extrapolated to October birds. In most of the categories of observation well over 100 birds were studied. 


Comparing my bird to Gibbins results I found that- 83% of studied birds had a similar mantle colour to mine (20-30% saturated), 68% of the birds had similar bill markings to mine (red,no black), 70% had similar eye colour to mine (light to medium speckled), 68% had similar primary pattern (black to P5). 

The leg colour fell well within the 4 shades of pink illustrated (#678) but no percentages were given for the individual shades. He did say 93% of  L. vegae had dull pinky-flesh colored legs. The bright pink legs seen in breeding season are lost to a certain extent during the winter.


Adult Vega Gull  - Sault Ste. Marie showing "pinky-flersh coloured legs"


Adult Vega Gull-Japan -Oct.25/06-  Osao and Michiaki Ujihara

The above bird from Japan in late October shows similar coloured legs and bill as well as a nearly all white head and a similar stage of primary moult.

The variation of patterns on P10 were illustrated in Gibbins study and the 4th one illustrated was very similar to my bird. All in all this study reinforced that in all its main characteristics this bird fell well within the limits of the majority of Vega Gulls studied in Japan.

So to conclude I want to adress three questions from easiest to hardest.

1.Why isn't this just a regular American Herring Gull?

This is fairly easy- First the mantle shade is out of range of this species. The reddish orbital ring is also not seen in American Herring Gull. The primary pattern and very broad white trailing edge would also be quite atypical(but probably not impossible)for this species. The darkish eye is also atypical but a small percentage of Herring Gulls will have eyes darker than this.

Adult Vega Gull-Sault Ste. Marie -showing darker mantle and classic "Herring Gull" structure

2. Why isn't this a American Herring Gull X Lesser Black-backed Gull (LBBG) hybrid.

The main argument against this is the primary pattern and the very broad white trailing edge to the wings. This wouldn't be something you would expect given that the  adult LBBG usually has only a small white spot on P10, minimal white tips to the primaries and a relatively narrow white trailing edge. On some occasions they will have a small window on P9  shown on the bird pictured below. None of the multiple pictures of adults LBBG I reviewed in many sources had as much or more white on the wings. 

All the pictures of presumed Lesser Black-backed X Herring hybrids I have seen have had a very odd pinkish- yellow leg colour as well as a considerably darker mantle than would be typical for Vega. A good example can be seen in Photo #7 on Jean Iron's excellent website.


Adult Lesser Black-backed Gull showing maximum amount of white on wings

3. Why isn't this a Great Black-backed(GBBG) X Herring Gull hybrid?

This is clearly the most likely alternative identification. In fact initially in the field this was my presumption. However as I watched the bird I was increasingly stumped by its relatively light mantle much lighter than I would expect for this combination. Next I just could account for the total lack of any GBBG structural characteristics. No sign of the massive bill or odd "skinny looking" flat head. The size was that of a medium size Herring with none of the long -legged look of GBBG. 

Below are multiple pics of presumed GBB X Herring Gull hybrids that I will use to illustrate some points. All of these birds have been considered GBBG XHerring hybrids by multiple authorities

Second winter GBBG X Herring hybrid

Notice the large stout bill, the GBBG-like head and long legs. Although this picture doesn't portray its size well it was quite tall appearing and larger than most of the Herrings.

Second winter GBBG X Herring hybrid

Again a very stout bill with a flat angular head. Larger than most of the Herrings and quite tall appearing.

Third winter GBBG X Herring hybrid

Another tall bird with a very flat head and relatively stout bill. Notice the mantle shade quite a bit darker than my bird. The eye in this third winter bird is already lighter than. A very nice picture of an likely adult GBBG X Herring can be viewed at this site:


Adult Vega Gull-Sault Ste. Marie-showing rounded head and relatively average "Herring Gull" type beak

The above bird shows no trace of GBBG structure that I can detect. This was obvious in the field were it fit in nicely with the surrounding Herrings many of which were bulkier and larger than it. 



Adult Great Black-backed Gull showing flat angular head and massive bill

The next reason this bird is not a GBBG X Herring hybrid is its primary and secondary flight feather patterns. Both the Herring and Great Black-backed Gulls have medium sized white trailing edges to the secondaries. My bird as is typical of Vega has a very wide trailing edge reminiscent or maybe even wider than in a Slaty-backed.


Adult Great Black-backed Gull showing medium width trailing white wing-edge and typical primary pattern


Adult Herring Gull showing medium width trailing white wing-edge and typical primary pattern


Third winter Herring Gull   Third winter GBBG X Herring hybrid
Both showing medium width trailing white wing-edge.

Below I will show pictures of a variety of adult Vega Gulls to illustrate the very broad white trailing edge to the wing along with the typical primary pattern usually with a large window on P10 and P9 and white tongue tips.



Adult Vega Gull, May/09 Gambell,Alaska




Adult Vega Gulls-Japan - Osao and Michiaki Ujihara

Compare the Vega Gulls from Japan and Alaska to my Sault Ste. Marie bird.


Adult Vega Gull- Sault Ste. Marie-showing very broad trailing white wing-edge as well as white-tongue tips to primaries

My final point is perhaps the most important of all and to me makes the identification of this bird as a Vega Gull secure. My bird is in relatively early prebasic molt with three retained old primaries per wing.
This is very typical of Vega Gull at this date. Ujihara noted that of 40 Vega Gulls he examined on Oct.25th,2006 all but 2 had retained primaries. Many still had retained primaries into late December.

Of the hundreds of adult American Herring Gulls I examined closely over the last two days I could not find a single bird with a retained old primary. Although moult is clearly a variable thing it would appear that Vega Gull is fairly unique in its late prebasic moult. Great Black-backed Gull typically is at this stage of moult in late August-early Sept. I have never seen a GBBG with retained primaries in late October.


Adult GBBG in active prebasic moult-Sept 1/2005 Virginia Beach

Although Vega Gull is clearly a very rare find in the east it would not seem any less likely than Slaty-backed Gull which is a regular visitor to western Lake Superior over the last five years. Michael Brothers had a very nicely documented adult Vega Gull at Daytona Shores last winter. Unfortunately young birds are a very challenging identification and most of these birds are likely never identified.

This bird has Herring Gull like size and structure with a darker mantle,  a reddish orbital ring, a very broad white trailing edge to the wing and a typical Vega Gull primary pattern. The eye clour, leg colour and bill pattern are all consistent with the majority of Vega Gulls studied by Chris Gibbins in Japan. To boot it is in active prebasic moult with three retained primaries a good 2 months after all the other candidate large gulls and hybrids should have been at this stage. I think this is sufficient evidence to identify this bird as an adult Vega Gull.

I am hoping this bird sticks around so I can document it in full winter plumage. I did search for it today without luck but it is likely still around and I will be keeping a close eye out.

Comments on this bird would be appreciated.
See ya

Kirk
zufelt_k@shaw.ca