WINTER SONGS OF THE PINE GROSBEAK

PETER TAYLOR, P.O. Box 597, Pinawa, MB. ROE 1L0

Both in appearance and voice, the calls and imitations of the calls of Pine Grosbeak is one of Canada’s other species. This medley is ut¬ most attractive winter . Bent’s tered more or less continuously, account of this species includes sev¬ sometimes for 5 minutes or more at eral tributes to the beauty of its a stretch. In contrast, typical song songs.1 In winter most of the Pine consists of brief but rich warbled Grosbeak’s vocalizations are flight or phrases with a “wild” quality, sug¬ contact calls but its repertoire in¬ gesting a loud Purple , and is cludes some quiet yet complex clearly audible at 100 m or more. A songs of the kind often called “whis¬ few Pine Grosbeak songs were inter¬ per song.” An interesting feature of mediate in volume and complexity these songs is the frequent imitation between the whisper and typical of other birds’ calls.2 Because so few songs, and were therefore difficult to birds sing in winter in Manitoba, I classify. have kept notes on this behaviour over an extended period. Here, I Pine Grosbeaks usually utter their summarize 78 observations of whis¬ whisper songs while perched in per singing by Pine Grosbeaks at, or trees, either alone or in small groups near, Pinawa, Manitoba between and otherwise unoccupied. Some¬ 1978 and 1995. They include 38 ob¬ times they sing, without interruption, servations (49%) of songs that in¬ while feeding on ash or lilac cluded mimicry of other species. etc. Singing has been noted in sun¬ “Typical” territorial song was noted shine, cloudy conditions, and even less frequently, about 15 times. during a snowstorm and at tempera¬ tures down to -35°C. In 47 cases The Pine Grosbeak is a common where the individual songsters could winter visitor to the Pinawa area. My be distinguished, 30 were adult 20 years of migration records indi¬ males (i.e. second winter or older), cate median first-arrival and last- de¬ four were definitely subadult males, parture dates of 24 October and 19 and 13 were either females or March, respectively. Breeding-sea- subadult males. son records in southeastern Mani¬ toba are exceedingly rare. Observations of whisper singing span the wintering period, from 14 Observations Whisper song of the October to 10 March (the former Pine Grosbeak is normally audible date, coincidentally, is a local early- from about 25 m under ideal condi¬ arrival record). However, 68 of the tions. Some especially soft renditions 78 observations (87%) occurred be¬ may be barely audible at 10 m. The tween 29 January and 10 March, in¬ song consists of a steady stream of dicating increased singing during the soft whistles, warbled phrases and month or so prior to migration which call-notes, often including muted ver¬ is usually under way by late Febru¬ sions of typical Pine Grosbeak flight- ary. Whisper singing has been noted

82 Blue Jay repertoires. Of the 18 singers, seven were males, four probably females and seven undetermined. Nearly every group of Pine Grosbeaks I ap¬ proached that day included at least one singer. This exceptional record is probably linked to a later-than- usual departure of Pine Grosbeaks from southern Manitoba, prompted by unseasonably cold weather.

All of the bird species imitated by the Pine Grosbeak share its summer range. Most frequently mimicked were the calls of American Robin (34 occasions) and Gray Jay (14). Less frequently mimicked were Lesser Yellowlegs (6), White-winged Cross¬ bill (5), Northern Flicker (5), Com¬ mon Redpoll (4), Hairy Woodpecker (4), Olive-sided Flycatcher (4), Greater Yellowlegs (1), and Yellow- bellied Sapsucker (1). As many as Pine Grosbeak Frank Walton five different species have been imi¬ tated in a single bout of song. The throughout the daylight hours, as song is so softly uttered, and richly early as 7:30 a.m. (just before sun¬ varied, that other imitations could rise) 14 February 1995 and as late easily have been overlooked. as 5:15 p.m. (half an hour before sunset) 24 February 1981. A majority On 40 of 78 occasions (51%), of observations (approximately 80%) whisper singing was noted without were between 9:00 a.m. and 12:00 evidence of vocal mimicry. However, a.m. but this is partly a reflection of this total includes instances when my own activities. the song was heard only briefly or with interfering background noise. In most cases, only one whisper Therefore mimicry is probably even singing bird was heard on a given more frequent than this percentage day. On six occasions, three or four suggests. well separated songsters were noted in one day (each individual is in¬ Discussion Complex sub-songs, cluded as a separate observation in sometimes described as whisper the totals discussed here). An excep¬ singing, represent a phase in the de¬ tional number of singing Pine Gros¬ velopment of song repertoire in beaks was heard in Pinawa on 4 young individuals of many March 1995. At least 18 individuals species, often commencing just a out of 80 birds seen in the space of few weeks after fledging.3 However, 90 minutes (8:00 A.m. to 9:30 a.m.) it is known that this behaviour is not were singing; 14 were uttering whis¬ restricted to juvenile birds, as illus¬ per songs and four intermediate trated by the present study. The tim¬ songs. At least nine of the 14 whis¬ ing of most of my observations sug¬ per singers included mimicry in their gests a link to the onset of breeding condition in late winter.

54(2). June 1996 83 I am aware of one other published be pleased to hear of any related ob¬ report of vocal mimicry by whisper servations on Pine Grosbeak song. singing Pine Grosbeaks; the singer was one of a pair at a nest near Rod- Acknowledgements I thank Reto dickton, Newfoundland on 24 June Zach and Rudolf F. Koes for helpful 1981.4 The species mimicked in that comments on a draft of this article case were American Robin, Gray Jay, Ruby-crowned Kinglet, Greater 1. BENT, A.C. et al. Life Histories of Yellowlegs, and possibly Red Cross¬ North American Cardinals, Gros¬ bill. Bent includes a reference to a beaks, Buntings, Towhees, , Sparrows, and allies (O.L. AUSTIN, loud imitation of American Goldfinch Jr., ed.). U.S. National Museum Bulle¬ flight calls by a group of Pine Gros¬ tin 237, Part One. Smithsonian Institu¬ beaks but this may refer to similar tion, Washington D.C. Pp. 326-346. phrasing of the two species’ calls 2. TAYLOR, P. 1979. Interspecific vocal rather than true mimicry.1 mimicry by Pine Grosbeaks. Can. Field-Nat. 93:436-437.

The observations described here 3. TERRES, J.K. 1982. The Audubon indicate that whisper singing, often Society encyclopedia of North Ameri¬ including mimicry of other birds’ can Birds. Alfred A. Knopf, New York, calls, is a fairly common behaviour of N.Y. Pp 833-834. Pine Grosbeaks in late winter. What¬ 4. WELLS, J. 1981. An observation of ever its biological function may be, it vocal mimicry in Pine Grosbeak. The certainly uplifts the human spirit on a Osprey Newfoundland Natural History Society Quarterly 12:82-84. cold winter day in Manitoba. I would

It is diversity by which life builds and saturates the rain . And diversity has carried life beyond, to the harshest environments on earth. Rich assemblages of swarm in the shallow bays of Antarctica, the coldest marine habitats on earth. Perch-like notothenioid fishes swim there in temperatures just above the freezing point of salt water but cold enough to turn ordinary blood to ice, because they are able to generate glycopeptides in their tissues as antifreeze and thrive where other fish cannot go. Around them flock dense populations of active brittlestars, krill, and other invertebrate animals, each with protective devices of its own. Wilson, E.O. 1992. The diversity of life. W.W. Norton and Company, New York. 424 pp.

84 Blue Jay