Vancouver Natural History Society
RARE BIRD REPORT FORM
Acorn Woodpecker (Melanerpes formicivorus)
2. Number of birds
3. Sex and age of bird(s), if distinguishable
Indeterminate. All of the field guides consulted indicate the main field mark for distinguishing the sex of Acorn Woodpeckers is the amount of red on the crown. In the male the red covers the entire crown from the top of the nape up to, and abutting the white forehead. The female has red only on the rear part of the crown and the portion of the crown above the eye and the forecrown abutting the white forehead is black. This bird had much more extensive red on the crown than what the field guides indicate a female should have, but less than what the guides indicate a male should have.
On this bird the red did not extend to the white forehead but ended (started) at a point directly above the eye. Between the leading edge of the red crown and the white forehead was a narrow strip of black (see exhibit #1 part B). As the field guides indicate that the leading edge of the female’s red crown ends at a point well before the vertical plane of the eye, the extent of red on the crown of this bird appeared to be closer in area to that of a male than a female. The presence of the black strip, however, between the red crown and the white forehead casts a degree of uncertainty as to the bird’s gender. A subadult male perhaps?
4. Names of observers (list all known to you, including yourself)
Five observers saw the bird:
1. Helen Carelse
21497 Spring Ave.
Maple Ridge, B.C.
2. Glen Carelse
21497 Spring Ave.
Maple Ridge, B.C.
3. Richard Kenzie
12101 – 202nd St.
Maple Ridge, B.C.
4. Amy Newman
21530 Spring Ave.
Maple Ridge, B.C.
5. Daniel Bastaja (author of this report)
22182 River Bend
Maple Ridge, B.C.
5. Date of observation
Sunday, June 16th, 1996
6. Time of day
7:00 a.m. to 8:10 a.m. Pacific daylight time.
7. Locality (describe as precisely as possible)
The bird was seen from the backyard of a house at 21497 Spring Ave. Maple Ridge, B.C. Spring Ave. extends west from 216th St. about 1.5 km north of the intersection of 216th St. and Lougheed Hwy in Maple Ridge. Two short blocks west of 216th St. the street ends in a cul-de-sac. Bordering the back-yard to the west is a small “green belt” area separating the cul-de-sac houses on Spring Ave. from the cul-de-sac houses on Cherry Place, a one block street extending east from 214th St. The bird was in trees in this green belt area.
8. Distance of bird(s)
Minimum: approximately twelve (12) metres (40 ft.)
Maximum: approximately thirty-eight (38) metres (125 ft.)
9. Optical equipment used
The author used Celestron “Nova” 7X35 extra wide angle binoculars. The other observers each had binoculars of a size and type undetermined by the author at the time of observation. Each observer saw the bird through a Bushnell “Spacemaster II” 25X60 spotting telescope.
10. Light conditions (sunny or cloudy, height of sun in sky, position of sun in relation to observer)
Mostly sunny. Scattered thin high cloud gave a “hazy” effect to the sky. The sun was relatively low in the sky (early morning) directly behind the observers. For most of the observation period, the bird was in exposed locations, at the tops of alder trees, snags, trunks and branches so it was well exposed to the light.
11. Duration of observation (how long did you actually watch the bird?)
The bird was in continuous view from approximately 7:00 a.m. to 7:48 a.m. and then again from 8:08 to 8:10 a.m. Total observation time fifty (50) minutes.
12. Size and shape of the bird (estimate size as compared with a familiar species; note especially if direct size comparisons with other species were made in the field
The bird was the same size as a Hairy Woodpecker. It was solitary during the observation period, but close direct size comparison was possible on two occasions. While perched on a snag, the bird was closely approached (within 2 metres) by a European Starling. It was somewhat larger than the Starling with a bulkier appearance. On the second occasion the bird was on the trunk of a small, dead fir tree, about 1 metre from the top of the tree, when an American Robin landed at the top of said tree. It was slightly smaller than the Robin.
The bird was typical woodpecker shape. The top of the head was rounded but the bird was able to raise the feathers on the rear part of its crown to form a very short, raggedy crest. The bill was straight, sharply pointed and approximately the same length as the bird’s head. In flight the wings were mildly rounded. At rest the tail extended well beyond the folded wings and the centre tail feathers were the longest, creating a wedge shaped appearance to the tail.
13. Description of bird (describe in detail plumage patterns, also shape and colour of bill and feet; describe only what you actually saw. If needed, use an extra sheet, draw a sketch, etc.)
Predominant colouration was black and white except for a large red patch on the crown. This patch was rectangular in shape extending from a point on the crown directly above the eye backward to the start of the nape. Aside from this red section, the bird had a very bold black and white head pattern as follows: The bill was grayish black. Around the base of the bill was a black band. This band was extremely narrow on the top of the bill but widened underneath to form a black “chin strap”. Behind this black band was a section of white. This section extended partially up the forehead, narrowed to a thin strip between the eye and the bill and then flared out below the eye to form a large white cheek patch and white throat. The white of the throat, particularly below the “chin strap” area, was very faintly tinged with yellow. Between the red crown and white cheek patch was a strip of jet black extending forward just enough to encompass the eye and crossing the forehead above the eye to form a black band between the white lower forehead and red crown. This strip of black was a continuous extension of the black colouration on the bird’s nape and back. At the forward extremity of this black strip was a very pale yellow eye, appearing almost white. The combination of bright red, jet black and bright white with sharp lines of demarcation between the colours, created a very striking appearance (see exhibit #1 part A).
Other field marks noted during observation:
- Nape, sides of neck, back, wings (both sides), and tail (both sides) solid jet black.
- Rump and upper tail coverts white.
- The black at the sides of the neck extended in a broad black band across the breast. The upper edge of this band formed a sharp line against the white of the throat. The lower edge of this band, against the white of the lower breast, was not a clean line but rather became a series of short, fine black streaks before giving way to the pure white of the lower breast.
- Lower breast, belly and under tail coverts white.
- Approximately halfway up the shaft of some of the primary flight feathers was a section of white. Several adjacent primaries had the white portion at the same location along the shaft creating a rectangular white patch in the wings. This white patch, visible on both sides of the wing, was most noticeable when the bird flew, but the bird preened at length, affording the observers excellent views of the white patch on the partially extended wing, while the bird was stationary.
- See exhibit #2 A & B for illustration of the preceding field marks.
- Legs dark gray.
- Four toes on feet.
14. Vocalizations (songs, calls ‘ describe in detail)
The bird made no vocalizations of any kind during the observation period.
15. Action and behaviour of bird(s)
The bird was first observed as it flew into the top branch of an alder tree. The stand of trees where the woodpecker was seen was tall alders and broad-leafed maples. The alders were relatively sparsely leafed and many of the branches were bare, giving the impression that the upper reaches of many of the trees were dead or dying. The bird spent most of the time in these small upper branches approximately 9 to 15 metres from the ground (30 to 50 ft.). It would creep lengthwise along a horizontal or diagonal branch and occasionally sit across a branch. Sometimes the bird would sit in more traditional woodpecker style, vertically on a large trunk or snag. Once in a while it would tap away but never too intently or for very long. The bird would then hop or fly a short distance to a nearby branch or to another tree. Once it flew to a dead fir tree about 9 metres (30 ft.) from the ground and once to the vertical trunk or a dead snag about 4 metres (12 ft.) from the ground. This latter instance was the closest it came to the ground and to the observing party, being only about 12 metres (40 ft.) away with its back towards the observers at that point.
It spent a large amount of time during the observation period preening, both lengthwise on a small horizontal branch, at the top of a snag, and vertically on the trunk of a snag. The period of preening on the small branch lasted a good ten minutes, affording all of the observers ample opportunity for lengthy scrutiny through the telescope. On occasion it would just sit at the top of a snag or the fork of a branch. In one such instance a European Starling landed on a small branch close by and hopped in the bird’s direction while giving mild alarm calls. Patently irritated at this invasion of personal space, the woodpecker flew directly at the interloper and drove it away.
Overall it appeared rather sedentary for a woodpecker. It spent relatively long periods of time in several specific spots and, other than arriving at or leaving the observation area, never flew very far. It appeared to prefer the top, sparsely leafed or semi-dead branches of the alder trees over the more heavily leafed maples.
The bird was observed continuously from 7:00 a.m. to 7:48 a.m. at which time it flew off in a northeasterly direction low over the roof of a neighbouring house. The duration of this flight was sufficient for the bird to display the undulating flight typical of woodpeckers. The bird flew back from the northeast to the stand of the alders about 20 minutes later (8:08 a.m.) and remained until 8:10 a.m. At this time it flew away in a west – southwesterly direction toward the houses on Cherry Place never to be seen again.
It should be noted that this bird (presumably the same bird) was first seen the previous morning (Saturday June 15th, 1996) by Helen and Glen Carelse at approximately 8:45 and 9:15 a.m. At that time it sat on the top of a high wooden fence bordering the backyard and came once to a suet feeder hanging on the back porch or the house.
16. Did the bird flock with other species? If so, what and how many?
No. The bird was solitary throughout the observation period.
17. Habitat (describe in detail)
The specific location is a strip of primarily indigenous flora left in its natural state, sandwiched between several suburban backyards. The total area covered by this “green belt” is perhaps one hectare. There is a stand of deciduous trees in this area, being mostly tall alders interspersed with broadleaf maple. Most of the alders have large bare sections on the upper branches indicating parts of the trees are dead or dying (see exhibit #4). There are numerous small snags and dead parts of trees, and the occasional small fir or cedar. Understory is relatively dense salmonberry, thimbleberry and blackberry.
The habitat surrounding this natural area is typical suburban single family detached homes. Manicured lawns and gardens, numerous native and ornamental trees, shrubs and hedgerows and small clusters of large native trees characterize the neighbourhood for many blocks in all directions.
18. Similar species you have considered, and reasons for eliminating these
Although the aforementioned head pattern is quite distinctive of this species, there are many North American woodpeckers of similar size that display a general black and white colouration and red on the head. As such, the author of this report was unsure as to what the rare bird committee might consider a “similar” species. To cover all bases and in the interest of brevity, I have prepared a table on the following page contrasting certain selected field marks of this bird with those of several other species. In cases where the characteristics displayed by another species is at variance with those displayed by this bird, I have placed an “X” beside the characteristic. The committee members will note that no species (reading horizontally on the table) has fewer than five “X’s”. This should effectively eliminate all of the species cited. If the committee is not wholly satisfied with this treatment, the author would be happy to provide, at the committee’s specific request, a more detailed contrast between this bird and any other species.
19. Previous experience with this species and other similar species
Richard Kenzie had seen Acorn Woodpeckers on one previous occasion. This was several birds seen at a California state park campground just north of Napa, California in 1981.
Helen & Glen Carelse had seen an Acorn Woodpecker for the first time the previous day (presumably the same bird). They were able to make the identification after consulting field guides.
Amy Newman and Daniel Bastaja had never seen an Acorn Woodpecker prior to this sighting.
Of the similar species cited in the table, the author has had previous experience with the following species:
- Red-headed Woodpecker (several times in Ontario)
- Red-breasted Sapsucker (many times in B.C.)
- Yellow-bellied Sapsucker (many times in Ontario)
- Red-naped Sapsucker (several times in B.C.)
- Hairy Woodpecker (many times everywhere)
- Lewis’ Woodpecker (several times in B.C.)
The remaining species were contrasted after consulting field guides.
20. Did other observers agree with the identification? If not, explain
All observers agreed with the identification without reservation.
21. List field guides, articles, etc. used to identify the bird(s). Did you consult them before, during, or after the observation?
The following field guides were consulted during the observation:
- Peterson “Field Guide to Western Birds”, Third Edition.
- National Audubon Society “Field Guide to North American Birds – Western Region”
- Golden Press “Birds of North America – A Guide to Field Identification”.
The following field guides were consulted after the observation:
- National Geographic Society “Field Guide to the Birds of North America”, Second Edition.
22. List any field marks which you saw on the bird(s) but did not write down until after consulting a field guide or other book
23. Did you make notes during the observation? If not, how long afterward?
Brief field notes and a sketch were made by the author during the observation, the originals of which are appended to this report as exhibit #3.
24. Did anyone obtain photos of the bird(s)? If so, who?
Helen Carelse took two photographs of the bird from a distance of approximately 12 metres (40 ft.) with a Fuji DL-7 camera. This camera is an inexpensive, fixed plastic lens camera that uses a drop in film cartridge. Amy Newman took a single photo of the bird with a 35mm SLR camera from a distance of approximately 15 metres (50 ft.)
A copy of this photo is appended to this report as exhibit # 4.
25. Date of completing this form
July 2, 1996
26. Your name
Daniel S. Bastaja
27. Address and phone no.
22182 River Bend
Maple Ridge, B.C.
Detail of Head
Top View and Bottom View
Original Field Notes
Photograph of Acorn Woodpecker