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education: birds of georgia Brown Noddy, Anous stolidus
Status: Accidental Offshore, 30 Aug 1992; 22 Aug 1993; 2 Sep 2003, 2 juveniles; 14 Sep 2008, 4 individuals at Navy Tower 6, 45 miles off Tybee Island ( Liberty ) and 5 individuals at Navy Tower 3, appx. 65 miles off Tybee Island ( Glynn ), among which were breeding adults, second summer and juvenile birds. Accidental onshore, one bird found dead Tybee Is. ( Chatham ) 1 Oct 1950; Little Cumberland Is ( Camden ) 9 Sep 1965 (sight record by Haney, C.); one bird found dead Cumberland Is. ( Camden ) 22 Jun 1989; and a sight record from Sapelo Is. ( McIntosh ) after Hurricane Erin 8 Aug 1995). Birds seen in Georgia waters in August and September are often found after the passage of hurricanes. The 9 individuals seen on 14 Sep 2008 represent a new high count for the state (Beaton, et al 2003) (2008 sightings pers. comm. P. Howard). A report of 4 individuals at the Charleston Bump 17 Sep 2005 is left in question after at least three of the individuals were later confirmed to be juvenile Sooty Terns (fide Dan Vickers who photographed the birds). Because of the small number of pelagic trips run in September, the true status of the species Offshore in late summer/early fall is poorly understood. Habitat: Breeding: Breed in "colonies on rocks, islets, and islands in tropical seas around the world to about 30 degrees north or south of the equator but going beyond these boundaries o the southern Atlantic Ocean" (Chardine and Morris 1996). The only breeding location in the continental U.S. is on Bush Key, Dry Tortugas National Park. FL west of Key West, FL. Also common breeders in Hawaii, Puerto Rico, and the U.S. Virgin Islands (Chardine and Morris 1996). Nests are placed in a wide variety of locations including the ground, trees, cacti, bushes, rocky cliffs, and human-made structures such as docks, jetties, and pilings (Robertson 1964). A single egg is laid and survival rate is high. When breeding, forages within sight of colony (Chardine and Morris 1996). Non-breeding: After breeding season, wanders widely over tropical seas, feeding on small fish. Often follows schools of predatory fish that force small fish to the surface (C.S. Harrison, pers. comm. as cited by Chardine and Morris 1996). Roosts on water, on floating objects, or on islands (Chardine and Morris 1996) Specific oceanographic requirements of habitat such as water temperature, salinity, and upwellings are poorly understood (Chardine and Morris 1996). Sightings in waters and along beaches of GA, SC, and n FL in August and September suggest a northerly pattern of post-breeding dispersal, but because sightings are often contemporaneous with the passage of hurricanes, many sightings could be of storm-driven birds (P. Howard, pers.comm.). Diet: Mostly small fish and squid, but also small crustaceans and marine insects. Squid appears to be less important in Atlantic Ocean than in Pacific or Indian Oceans (Morris and Chardine 1992). Feeds by "dipping" or catching prey while hovering over the surface (Sibley 2000). Occasionally belly-flops into water to catch prey, which is immediately swallowed and not carried in bill as is commonly done by other terns (Ainley and Boekelheide 1984) Identification: Breeding adults: A medium sized tern (L 15.5 in; WS 32 in; WT 7 oz) with a relatively short and double-rounded tail that appears bulbous on the end (Sibley 2000). Tail is not forked. Males and females are indistinguishable even in hand (Olsen and Larsson 1995), although some experts note that males are slightly larger than females (Chardine and Morris 1996). Upperparts rich chocolate brown. Underparts brown but with a gray cast. Wing coverts lighter brown than secondaries or blackish primaries. Forehead frosted white, brightest just over bill, with frosted crown gradually blending into grayish hindneck. Black lores in sharp contrast to frosted forehead, with black curving up in front of dark brown eye. Prominent white eye-ring extends around lower half of eye with only a short area of white centered over the eye. Bill black, heavy and slightly decurved. First summer birds (Mar-Aug) show white forehead but retain dark crown and have worn wing coverts, which are lighter brown than the rest of the plumage. Full adult plumage reached in third summer of life. Juvenile (first year) plumage: Similar to adult breeding plumage except darker overall and "duller brown with white on head restricted to band across lower forehead and extending above eye only with crown dark brown. Juvenile appearance similar to adults, a trait that is most unusual and possibly unique within Laridae, where immature birds (1-2 yr old) usually have clearly different plumage from adults" (Chardine and Morris 1996). Similar species: At sea, juvenile Sooty Tern, Sterna fuscata , can be mistaken for Brown Noddy. Juvenile Sooty Tern has white underwing coverts and whitish vent, while Brown Noddy has dark underwing coverts and vent (Sibley 2000). Migration: Migrates between breeding colonies on oceanic islands and marine feeding areas where it spends the nonbreeding season. No published information about nonbreeding range of species, although sightings and recoveries of birds from areas far from land suggest that the species wanders widely (Chardine and Morris 1996). Birds seen in GA waters are at least 750 miles from the nearest breeding colony in Dry Tortugas National Park, FL (P.Howard pers.comm.). Arrives on breeding grounds a few weeks before breeding begins and departs several seeks after breeding cycle ends. In Dry Tortugas NP, FL birds appear in mid- Jan and disappear completely by early Nov (Stevenson and Anderson 1994). Birds seen in GA waters in late Aug and Sep suggest post-breeding dispersal occurs during those months (P Howard, pers.comm.) Little is known about migratory behavior (Chardine and Morris 1996). Birds seen off GA 14 Sep 2008 rested on Navy Towers then foraged in the immediate area of the ocean for bait fish, often feeding along the surface with Sooty Terns (P. Howard, pers. comm.). Conservation: Like all nesting seabirds, vulnerable to human disturbance, predators, and human depredation. Adults are shot for food at some locations in Caribbean (Haynes 1989), but the practice not common enough to affect populations (Chardine and Morris 1996). In many locations around the world, the collection of seabird eggs for human consumption has a serious negative impact on populations although in some places like the Bahamas, and Hawaii, the practice has largely ceased (Harrison et al. 1984) The introduction of predators is an important threat to the species, and infestations of black rats in Dry Tortugas NP, FL in years past caused population declines (Robertson 1964). In some locations in Hawaii (Harrison 1960) and the Caribbean (VanHalewyn and Norton 1984), the presence of mongooses has destroyed all seabird nesting. Works Cited: Ainley, D.G. and R.J. Boekelheide.1984. An ecological comparison of oceanic seabird communities of the south Pacific Ocean. Stud. Avian Biol. 8:2-23. Beaton, G., P.W. Sykes, and J.W. Parrish, Jr. 2003. Annotated Checklist of Georgia Birds. Occasional Publication No. 14, Georgia Ornithological Society. Chardine, John W. and Ralph D. Morris. 1996. Brown Noddy (Anous stolidus), The Birds of North America Online (A. Poole, Ed.). Ithaca: Cornell Lab of Ornithology, Retrieved from the Birds of North America Online: http://bna.birds.cornell.edu/bna/species/220 doi:10.2173/bna.220 Harrison, C.S.1990. Seabirds of Hawaii, natural history and conservation. Cornell Univ. Press, Ithaca, NY> Harrison, C.S., M.B Naughton and S.I. Fefer. 1984. The status and conservation of seabirds in the Hawaiian archipelago and Johnston Atoll. Pp. 513-526 in Status and conservation of the world's seabirds (J.P. Croxall, P.G.H. Evans, and R.W. Schreiber, eds.). ICBP Tech. Publ. no.2. Haynes, A.M. 1989. Human exploitation of seabirds in Jamaica. Biol. Conserve. 41: 99-124. Morris, R.D. and J.W. Chardine. 1992. The breeding biology and aspects of the feeding ecology of Brown Noddies nesting near Culebra, Puerto Rico, 1985-1989. J.Zool. (Lond). 226: 65-79. Olson, K.M. and H. Larsson. 1995. Terns of Europe and North America. Princeton Univ. Press, Princeton, NJ. Robertson, Jr. W.B. 1964. The terns of the Dry Tortugas. Bull. Fla. State Mus. 8: 1-94. Sibley, David A. 2000. The Sibley guide to birds. Alfred A. Knopf, New York. Stevenson, H.M. and B.H. Anderson. 1994. The birdlife of Florida Univ. Presses of Florida, Gainesville, FL. Van Halewyn, R. and R.L. Norton. 1984. The status and conservation of seabirds in the Caribbean. Pp. 169-122 in Status and conservation of the world's seabirds (J.P. Croxall, P.G.H. Evans, and R.W. Schreiber, eds.). ICBP Tech. Publ.no.2.
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