Bird of the Month: May 2022 - Connecticut Ornithological Association

Arctic Tern

Photo credit: Arctic Tern (Sterna paradisaea) Bantam Lake, 05.13.2022 Larry Master www.masterimages.org

STATE YEAR LIST for 2022:

During May birders reported FORTY-FOUR additional species, bringing the state year list up to 295 species.

During January birders reported 175 bird species, which initialized this year’s eBird CT “state year list.” FOUR species were added in February, and in March EIGHTEEN additional new species were added to our state year list (bringing the state year list up to 197 species as of the end of March). During April birders reported FIFTY-THREE additional species, bringing the state year list up to 250 species (actually up to 251, due to the 1 for the swallow-tailed kite which had not been reported to eBird yet).

The proposed top three rare birds for CT for May are:

N/A – Pending: Violet-green Swallow. This would be the first state record, if accepted. No photo was taken, but bird was well described. Seen on May 8 by David Lawton.
#1: Arctic Tern. Multiple observers. Only a few previous state records.
#2: Black-necked Stilt.

RARE BIRD SPECIES of the month

Arctic Tern

NOTE: There were only five prior records of any Arctic Terns in the state of Connecticut previously. A more comprehensive report on this May 13, 2022 unprecedented fallout incursion of Arctic Terns in Connecticut is expected to appear in The Connecticut Warbler later this year. Here is just a brief overview of the event.

Arctic Terns navigate from one end of the planet to the other, and in mid-May many Arctic Terns are usually migrating north over the ocean, on their way to more northerly New England and beyond. Do these great navigators ever get lost? Rarely, perhaps this year, when the weather caught up with them, with both strong easterly winds and fog, resulting in a downing/fallout of many individuals across inland Connecticut for the first time in such numbers since birders here have kept records.

The red icons show all the May 2022 sightings of Arctic Tern (mostly May 13), compared with all prior reports in the blue icons.

Arctic Tern, from Cape May, NJ to Nova Scotia. eBird map imaged on June 4, 2022:

Greg Hanisek’s 5/20/2022 article in the Republican American comments on the Arctic Terns in Connecticut on May 13, 2022:

Nature: It’s a first: Arctic terns drop in on Connecticut

“this incredible fallout had dropped arctic terns in double figures on lakes across a wide swath of the state. A combination of onshore winds and fog had pushed large numbers inland, where lakes offered a chance for them to come down and readjust their movements.

Nothing like this had been witnessed before in Connecticut, but nature never stops punctuating the reliable and predictable with amazing surprises.”

And while Nick Bonomo was one of many timely postings about the sightings on the CTBirds listserv on May 13, 2022, his blog of June 2009 (https://www.shorebirder.com/2009/06/bird-to-watch-for-in-ct-arctic-tern.html) was perhaps more prescient:

“A bird to watch for in CT: Arctic Tern”

Nick mentions, “Spring migration – This species is occasionally seen in our region during mid-late May, often during an out-of-season nor’easter or other inclement weather.”

Weather

https://www.wpc.ncep.noaa.gov/NationalForecastChart/map.php … for May 12, 2022:

https://www.wpc.ncep.noaa.gov/dailywxmap/dwm_500ht_20220512.html … for May 12, 2022:

For May 13, 2022:

Range in Northern Hemisphere

Arctic Tern: From BirdLife International

https://www.iucnredlist.org/species/22694629/132065195

Birds Of The World includes this informative report on the diet of the Arctic Tern:

Diet
Opportunistic forager; diet may vary from place to place, from year to year, and rapidly in response to diurnal and tidal cycles and activities of under-water predators. In polar regions, melting and movement of coastal and lacustrine ice greatly influence food availability. Information notably sparse for inland nesters, and for nonbreeders, especially in Antarctica.
Major Food Items
Fish, particularly for feeding young; generally account for most biomass even where invertebrates are much more frequently eaten. Access to sufficient fish may be necessary for successful breeding: No chick diets without fish reported. For additional lists of prey, see Cramp 1985a . In early spring occasionally feeds on berries.
Most frequent fish prey are small, schooling species commonly caught in open water, at tide rips, and over predators. These are usually 1- or 2-yr-olds, from families Clupeidae (herrings), Gadidae (cods, hakes, pollocks), Ammodytidae (sandlances or sandeels), and Osmeridae (capelin, smelts). Less frequently reported are Atherinidae (silversides) and Scombridae (mackerels). Gastero-steidae (sticklebacks) are frequent, although often rejected by chicks. Benthic and cryptic fish species usually caught while foraging over tidepools, beds of algae or sea grass. Most frequent families are Cottidae (sculpins), Gobiidae (gobies), Cyclopteridae (lumpfishes), and, in sandy areas, Pleuronectiformes (flatfishes). Vertebrates other than fish infrequent: 1 record of tadpoles (Rana; Kirkham 1986).
Crustaceans reported in all large prey samples. Amphipods (to >25 mm long) frequently most numerous taxon. These mostly caught in marine or brackish habitats by dipping or plunging, but occasionally while walking (beachfleas; Kirkham 1986). Other crustacean groups represented are decapods (crabs and shrimps), especially caught at low tide, and euphausiids (krill), which are irregularly reported; their propensity to swarm contributes to localized abundance.
Diverse insects are eaten and are sometimes principal prey; for many, their mode of capture cannot be assigned with certainty, so the following categories are not exclusive. Caught in air: swarming ants and dipterans, including craneflies (Tipulidae; e.g., Parmelee and MacDonald 1960). Catching tiny midges in flight by swooping close to water surface described as “chironomid ballet” (Von Haartman 1982). In Finland increasingly reliant on chironomids, which are now increasing in number owing to eutrophication. From water’s surface: many moths (Lepidoptera), adult terrestrial beetles (Coleoptera), and adult dipterans fed to chicks, especially at offshore colonies, likely to have been floating, trapped in surface layer. Also feeds on adult dytiscid water beetles (Sutton 1932b). Many adult dipterans (e.g., mosquitoes [Culicidae]) with aquatic larvae are picked from surface as they emerge. Underwater: Importance of dipteran larvae captured underwater unknown. Larvae of aquatic Dytiscus beetles (“water tigers”) were most frequent insect prey at Churchill, Manitoba (Kirkham 1986). Reported taking caterpillars (Lepidoptera) from grass stems in Iceland (Bannerman 1962).
Annelids sometimes important prey: mostly marine polychaete worms, such as spawning Nereis (Bianki 1967), but also occasional terrestrial earthworms (Lumbricidae; Gudmundsson 1956, Ash 1984, Hall et al. 2000); one report of a leech (Hirudinea; Kirkham 1986). Other marine invertebrates brought to chicks include pelagic mollusks: Pteropoda (sea butterflies; Kirkham 1986), Aplacophora (solenogasters; 1 record in Gulf of Alaska; Baird 1983), and cephalopods (Cramp 1985a). Adults observed feeding on ctenophores and hydrozoan medusae in Alaska (Kirkham 1986).
No detailed studies in Antarctica: Feeding on fish and euphausiids reported (e.g., Bierman and Voous 1950, Griffiths 1982).
https://birdsoftheworld.org/bow/species/arcter/cur/introduction