Black-billed Cuckoo Coccyzus erythropthalmus The Black-billed Cuckoo breeds from cen­ tral Alberta across southern Canada to Nova Scotia and Prince Edward Island; in the U.S. it breeds as far west as Wyoming, and south to Missouri and North Carolina. It is found in a wide variety of habitats, in­ cluding dry pastures with fencerows, brushy hillsides, and broken hardwood and mixed woodlands, as well as river bottom thickets and marsh edges. Vermont provides fine Black-billed Cuckoo habitat, and in some years the species may be found-albeit thinly distributed-any­ where in the state away from the higher them to early "economic ornithologists," mountain elevations. Cuckoos are not easy whose praises for the most part overcame birds to confirm; statewide only 24% of pri­ earlier objections to the birds as cowards ority block sightings resulted in confirma­ and habitual nest robbers (Samuels 1880; tion. Black-billeds are easy to locate in May, Bent 1940). thanks to their familiar monotonic cucucu Black-billed Cuckoos nest in a wide vari­ song, delivered in a series of 2 to 5 notes ety of shrubs and trees, both deciduous and with brief pauses between series, by night coniferous. Nests are typically 0.6-3 m as well as by day. Once nesting is under (2-10 ft) above the ground, but occasion­ way, however, they quiet down and become ally lower or higher; this species has been furtive, skulking, and reclusive birds, seen known to nest on the ground in herbaceous briefly, if at all, while slipping into the depths cover, though such a site is exceptional. The of a woodland. nest is a loosely constructed platform of Black-billed Cuckoo numbers vary from twigs (sometimes with an admixture of bark year to year, depending, apparently, on the strips or rootlets or burrs), either unlined or abundance of their favorite insect prey. One fairly substantially lined with leaves, grass, reference called this bird "wholly insec­ catkins, pine needles, and/or fern material. tivorous" (Martin et al. 1951), but accord­ Clutches contain 2 to 4, most commonly 3 ing to most researchers it takes some wild. eggs (rarely, as many as 8, but larger clutches fruit and small animal prey as well (Pearson probably involve two or more females); eggs 1936; Terres 1980). Caterpillars are the are a dull, light blue-green, and are typically usual favorite food. Examination of 121 darker and slightly smaller than the similar stomachs of this species turned up 2,771 eggs of the Yellow-billed Cuckoo. Egg dates caterpillars (Forbush 1913), most of them of from Massachusetts and New York (Bent the destructive hairy variety (tent cater­ 1940) and from Maine (Palmer 1949), to­ pillars, fall webworms, mourning cloak cat­ gether with Vermont Atlas Project data, sug­ erpillars, and tussock moths, including gypsy gest that the majority of clutches in these moths). Few birds will touch these hairy latitudes are initiated during the first 2 weeks caterpillars-cuckoos' stomachs are said to ofJune. Six Vermont records for eggs range become "so felted with a mass of hairs and from June 7 to July 25. spines that it obstructs digestion," where­ Young cuckoos, hatched coal-black and upon the birds shed the stomach lining and nearly naked, grow at an astonishing rate on grow a new one (Forbush and May 1939). a diet of regurgitated caterpillars. A week The cuckoos' appetite for this fare endeared after hatching (which is often asynchro- 126 Species Confirmed as Breeders in Vermont n° n° ,,0 ~ [!] 0 ,,0 DO 0 0 CD Jr[!] 0 ~ ~ [8J [!] • [!] [8J[!] C!b ~ cf· e[!]O [!] ~ D~ e ~ [!] [!] • ~ ~ [!] c:fl [I] m· C!b ~ 0 • ~ • [!J 0 It .~ ell• cilij [ij.[!j9:J ep • [8J [!j 0 440 No. of priority blocks in which recorded [It]~ [!] TOTAL I34 (75%) [!J DO ( • • Possible breeding: 62 (46% of total) [!J~h Probable breeding: 40 (30% of total) •• • [It]~ Confirmed breeding: 32 (24 % oftota!) ~e •• • 0!J [!Je• [!J [It] II • .. Physiographic regions in which recorded .~ % of ~. ~ .cJ!l %of species' • e no. of region's total ·e priority priority priority [I]~ [!] [!J[!] • [!j blocks blocks blocks [!][!Je• oee[!J· Champlain Lowlands 27 87 20 ~. Green Mountains 41 76 3° [It] North Central • [!J 13 68 10 ~ 10 30 50 Northeast Highlands 31 4 4)0 i ", ~ 0 4)0 East Central 13 68 10 20 • • 10 , Taconic Mountains 16 < 100 12 [!J B Eastern Foothills 19 79 14 • V • •• ~ n° n° DOUS) they may be climbing about on limbs Eastern Wood-Pewee, Cedar Waxwing, Gray near the nest; they hasten feather devel­ Catbird, Wood Thrush, Yellow Warbler, and opment by using their bills to strip the Northern Cardinal. covering from their quill feathers. The Black­ In spring, Black-billed Cuckoos arrive in billed Cuckoo is generally considered single­ Vermont in mid May. An April 20, I977 brooded in the northern parts of North arrival in Weathersfield (RVB, Spring I977) America; late summer egg records for the was exceptional, besting even the inland Northeast may be the result of a breeding New York record of Apri125 (Bull I974). cycle skewed by erratic local prey popula­ Fall migration peaks are small in this soli­ tions (see the Yellow-billed Cuckoo species tary species, but records suggest that most account). Although the Black-billed species migrants move through Vermont in Sep­ usually builds its own nest "as every other tember; wintering grounds are in north­ self-respecting bird does" (Gladden I936), western South America. Sightings of Black­ the family tendency toward brood para­ billed Cuckoos are rare in Vermont after sitism appears sporadically; eggs have been mid October. found in nests of the Yellow-billed Cuckoo, ALAN PISTORIUS Black-billed Cuckoo I27.