Sooty Terns Are Back
Christmas Bird Count a Success
Masked Booby to Nest on Middle Key

By: Debra Hess
Yankee Freedom II Naturalist

Six Sooty Terns were observed on January 17th cruising over Bush Key during the day and large numbers of Terns were heard calling at night during the Christmas Bird Count (Dec. 16-18).

The actual arrival of large numbers (several thousand) occurred around January 26th, and this is the earliest ever recorded for these Terns for their nesting season. Their arrival has coincided with several strong cold fronts which may spell disaster for the early egg laying. The Terns have been arriving earlier and earlier for nesting for about 15 years – researchers say Sooty Terns may be an indicator species for global warming. But those earlier arrivals leave the birds subject to egg predation from migrating gulls and the effects of springtime cold fronts stressing the colony.

Nesting Sooty’s with eggs

Magnificent Frigatebirds are courting and laying eggs. November and December mark peak periods of courtship for this awesome bird and numerous birds were observed with eggs on the Christmas Bird Count. Male Frigatebirds build the nest and display for females. The females care for young at least a year – so females far outnumber males in the colony.

I departed Key West on Tuesday January 16 on the Fort Jefferson (the Dry Tortugas National Park Supply Vessel) with five other bird watchers (Sonny Bass, Elsa Alvear, Michelle Davis, Larry Manfreidi and Rafael Galvez) for the 2008 Christmas Bird Count.

It was a gorgeous day – clear and calm – and we enjoyed sightings of many Northern Gannets, several Pomarine Jaeger, Brown Booby, Magnificent Frigatebird, Laughing Gull, and Royal Tern. After arriving at Fort Jefferson we searched the parade ground and Garden Key, locating an Eastern Phoebe.

I had been seeing this bird for several weeks (as of February 3rd it was still at Fort Jefferson) and it is a new winter record for Dry Tortugas National Park. Unfortunately we could not locate an Eastern Wood Pewee which I had been seeing in previous weeks – which also would have been a new winter record.

We found several species of warbler including Palm, Yellow-rumped, Pine (these birds were a surprise as Pine Warblers are not well known in the Tortugas), Black throated Green, Northern Parula, and Common Yellow throat. All these warblers were seen again on Wednesday making them official for our count and Larry added an Orange-crowned Warbler as well.

Tuesday evening we heard Sooty Terns calling out over the Gulf of Mexico as they start staging for nesting season. They feed by day over the open ocean but start flying into the nesting area at night – first near and later over Bush Key. Hearing these birds this early probably means early nesting again this Spring.

Count day started with half our party (Michelle, Elsa and Rafael) traveling to Loggerhead Key. Their special birds included Piping Plover and Dickcissel – both excellent birds for the Dry Tortugas. Sonny, Larry and I birded first on Garden Key and later Bush and Long Key. Michelle had located an America Pipit
on Tuesday evening which we observed on the north coaling dock beach.

Two Whimbrels and a Willet were on the south coaling dock, also a Common Tern among the Royal Terns (the Common Tern is an unusual sighting in the Dry Tortugas).

An additional Common Tern was observed on Loggerhead Key.
Long Key found numerous Magnificent Frigatebirds with eggs and well over 90 nests – and many males displaying. We also observed a Great Blue Heron and numerous Yellow Crowned Night Heron. I located the American Crocodile that has been residing in the Tortugas for over 5 years between Long and Bush Keys in a tidal pool.

Bush Key has several Savannah Sparrows.

We all reunited for lunch and afterward we departed by boat to search Hospital, Middle, and East Keys. No Masked Booby were found on Hospital Key (normal nesting location in recent years) but near normal numbers were counted on Middle Key along with lots of Brown Booby. Hurricane Ike damaged Hospital Key – severely depleting it of sand – while Middle Key gained a lot of sand making it the choice for nesting Masked Booby this season. The Masked Booby appeared to be sitting on eggs but unfortunately it was quite breezy on Wednesday afternoon and sea conditions prevented us from landing on any of these islands. However, the rough sea conditions by the boundary markers of Dry Tortugas National Park produced a Cory Shearwater flyover which thrilled all of us. This was the first ever sighting of this bird on the Tortugas Christmas Count and an excellent sighting for the Tortugas.

Rough sea conditions that keep the birds airborne can produce excellent birding from the top deck of the Yankee Freedom II on the way to the Dry Tortugas including multiple sightings of Brown and Masked Booby, Northern Gannet (both immature and mature), Jagears (both Pomarine and Parasitic) and occasional sightings of Shearwaters (Cory and Audubon) or Petrels.

The Christmas bird count netted 41 species total, listed below:
Masked Booby, Brown Booby, Northern Gannet, Brown Pelican, Magnificent Frigatebird, Great Blue Heron, Cattle Egret, Yellow-crowned Night Heron, Turkey Vulture, Sharp-skinned Hawk, American Kestrel, Killdeer, Black-bellied Plover, Piping Plover, Willet, Whimbrel, Ruddy Turnstone, Sanderling, Laughing Gull, Ring-billed Gull, Herring Gull, Royal Tern, Sandwich Tern, Common Tern, Sooty Tern, Cory’s Shearwater (first for Dry Tortugas), White-winged Dove, Belted Kingfisher, Eastern Phoebe, American Pipit, Orange-crowned Warbler, Northern Parula, Yellow-rumped Warbler, Black-throated Green Warbler, Pine Warbler (two birds very rare here), Prarie Warbler, Palm Warbler (both eastern and western races), Common Yellowthroat, Dickcissel (first winter record for Dry Tortugas), Savannah Sparrow, Grasshopper Sparrow.

Other birds of interest in winter 2008 – 2009:
Jan. – Rose-breasted Grosbeak
Dec. – arrival of many Black Skimmers
Nov. – Eastern Wood Pewee, Eastern Phoebe

Photo Credits: Christmas Bird Count –; Frigatebird – Julie Marcero; additional photographs by Deb Hess.

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