Sunday, September 14, 2014

The Birds of Post-Tropical Hurricane Arthur

I haven't been birding very long so I had only experienced one storm induced bird fallout before Arthur hit NS in 2014. In late April of 2012 there was an influx of southern breeders to Nova Scotia. High winds were experienced overnight on the 23rd and into the morning on the 24th. The maximum wind gust was measured at 85 km/h at Yarmouth. The sustained overnight winds were between 37 and 57 km/h and almost consistently at around 160 degrees (~SSE). The large southerly component to these winds would have assisted spring migrants heading north and facilitated an overshoot further north of their intended destinations. The weather systems had created a south-westerly flow of wind up the east coast of the US bringing the birds towards NS. Some analysis can be found in a message by Ian McLaren on the NS-RBA.

The highlights of this fallout for me were a Baltimore Oriole, Rose-breasted Grosbeaks, a Blue Grosbeak, Indigo Buntings, a Yellow-throated Warbler, a House Wren and a Summer Tanager.

Summer Tanager
Yellow-throated Warbler

Blue Grosbeak

The July 2014 event was much different from the April 2012 fallout. In early July there was no migration so no migrating songbirds were brought to NS. Hurricane Arthur reached Category 2 status and hit North Carolina with 160 km/h winds. It then passed just off of Cape Cod and was downgraded to a post-tropical storm before hitting NS. The force of Arthur's winds was enough to scoop up many coastal breeding birds in North Carolina and carry them towards NS. The different circumstances of this weather event provided an entirely different list of species for the awaiting birders in NS. A similar storm hit NS in 1968 and is described in Vol. 11, Spring 1969 of the NSBS Newsletter. In September of 2010, Hurricane Earl brought a similar list of rare birds to NS (see Sept. 2010 NS-RBA posts) as did Hurricane Wilma in 2005 (NS-RBA posts). Post-Tropical Storm Arthur of 2014 and its birds will also be analyzed in a future edition of Nova Scotia Birds, the quarterly publication by the Nova Scotia Bird Society.

Hurricane Arthur's track - Wikipedia

On Saturday morning (July 5, 2014) a few groups of birders headed out to the coasts of SW NS in the hopes of seeing some interesting birds brought in by the storm. Post-Tropical Storm Arthur was forecast to hit NS that morning and we wanted to be ready for it. On Friday night a radar image was being circulated around showing a large number of birds stuck in the eye of the storm.

Radar image showing birds in the eye

Bertin d'Eon and I headed to Ingomar, Ronnie d'Entremont and Sharron Marlor were at Baccaro Point and David Bell was at Cape Sable Island (CSI) along with the local CSI birders. The first report of a storm bird was a Laughing Gull at Baccaro by Ronnie and Sharron. Soon after that the reports were coming in fast. Bertin and I had found a few Storm-Petrels in Ingomar but the many reports from CSI by David Bell were too much so we headed to the island. David had been texting me sightings of both Storm-Petrels, Purple Martins, Laughing Gulls, Forster's Terns and jaegars.

Our first stop on CSI was Cripple Creek Wharf. Within minutes we had spotted a few Laughing Gulls and 2 Forster's Terns. Both of these species were lifers for me. I slowly crawled to a group of Laughing Gulls on the sandy beach to get some photos. To my amazement, a few of them were walking directly towards me and were within 3 feet of me. They must be accustomed to people and were probably not as wary as usual due to their fatigue after fighting the storm.

Immature Forster's Tern - Cripple Creek Wharf, CSI - July 5, 2014.

Adult Forster's Tern - Cripple Creek Wharf, CSI - July 5, 2014.

Many exciting birds were found on July 5th but the weather didn't allow for any great photography. Late in the day on Saturday reports started coming in about Black Skimmers at Mavilette and in Yarmouth. Ronnie and I woke up early on Sunday and drove to Yarmouth where we found 5 Black-Skimmer and later to Mavilette where there were 14 Black Skimmers, 2 Gull-billed Terns and 4 Laughing Gulls.

Black Skimmer - Overton - July 6, 2014

Black Skimmer - Mavilette - July 6, 2014

Black Skimmer - Mavilette - July 6, 2014

On Sunday night I headed back to CSI and got some photos of the vagrant terns that had first been seen the day before.

Gull-billed Tern - The Hawk Beach - July 6, 2014

Gull-billed Tern - The Hawk Beach - July 6, 2014

Royal Tern - The Hawk Beach - July 6, 2014

By Sunday night there was a large grouping of Laughing Gulls that had amassed in West Pubnico on a resident's lawn. The property owner was feeding them pork chops that night and they were very pleased to get such great service.

Adult Laughing Gull - West Pubnico - July 6, 2014

In the end, Arthur added another 4 birds to my life list. The new additions were Laughing Gull, Forster's Tern, Royal Tern and Black Skimmer. Many other rarities were reported throughout the province. Below is a list of interesting birds that appeared in NS in the days following the storm.
  1. Laughing Gull
  2. Black Skimmer
  3. Parasitic Jaeger
  4. Long-tailed Jaeger
  5. Purple Martin
  6. Leach's Storm-Petrel
  7. Wilson's Storm-Petrel
  8. Royal Tern
  9. Sandwich Tern
  10. Least Tern
  11. Gull-billed Tern
  12. Forster's Tern
  13. Black Tern
  14. Caspian Tern
  15. Harlequin Duck
  16. Glossy Ibis
  17. Red-necked Phalarope
  18. Black-necked Stilt (reported July 13 at West Head, Shelburne County - may not be attributable to the storm. See comments by Eric Mills on the NS-RBA)
David Bell spent a lot of time seawatching and birding Cape Sable Island on that weekend. Here are his eBird checklists.

July 5, 2014 - Cape Sable Island eBird Checklist
July 6, 2014 - Cape Sable Island eBird Checklist

A similar event also occurred in 2010 with Hurricane Earl. See below for eBird checkists from Shelburne County from Olivier Barden.

Sept. 5, 2010 - Cape Sable Island eBird Checklist
Sept. 5, 2010 - Baccaro eBird Checklist

In late October of 2005 Hurricane Wilma brought, Laughing Gulls, rare terns, swifts, Black Skimmers and even 3 Magnificent Frigatebirds (reported by Raymond d'Entremont) in Pubnico. Information can be found on the NS-RBA for October of 2005.

The terns were noted throughout most of the atlantic coast of NS from Halifax to Yarmouth but the Black Skimmers were only reported at Mavilette, Yarmouth, Seal Island, Surette's Island, Pinkney's Point and Cape Sable Island. These locations match up quite well to where the storm's eye made landfall. From this we should be able to conclude that the Black Skimmers were in the eye of the storm.

It has now been 2 months since Hurricane Arthur and most birds have either returned to the south or have died. I've heard of a few dead Laughing Gulls and Black Skimmers around SW NS. The most numerous of the rarities were the Laughing Gulls. I had monitored one grouping of these gulls in the days after the storm and took note of the numbers. See the chart below for the count of individuals near the war memorial in West Pubnico in the days after the storm.


The Laughing Gulls from the area were grouping together for a few days until they peaked at 100 individuals on July 8, 2014. The number shrank quickly and by July 12, 2014 there were no Laughing Gulls left at that location. The last gull that I observed was on September 7, 2014 in Yarmouth Harbour. In the days just after the storm there was a very small percentage of immature Laughing Gulls (maybe 5%), this percentage grew as time passed and the most mature birds returned to the south. A group of 18 birds that I had found on August 3 in Yarmouth were made up of 15 immatures and 3 adults (83%). By that date the mature birds were beginning their moult into basic plumage.

I will eagerly be awaiting the next hurricane and its vagrant birds. All of my photos of the storm birds can be found at my Flickr page.

8 comments:

  1. Amazing photos and information...Excellent...

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  2. I had a feeling there would be a sexy graph in this post somewhere! A nicely summarized event, Alix.

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  3. Great job on photos and all the info!! I can't believe you haven't been birding for years!

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  4. Thanks for the comments everyone. I think it is just about time for another hurricane. :)

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