ML620061445
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Details submitted to OBRC and accepted. Report included below but abbreviated due to eBird space limitation: Age: 1st winter, basic plumage. Time: 12:45 to 13:45 hrs. Dates bird known to be in area: 14 December 2003 to 1 January 2004 Coordinates: NAD 83 42°58'46" N, 79°54'17" W. Habitat (Figure 1): Small spring fed stream full of emergent aquatic vegetation. Area surrounding creek dominated by cattails and shrubs such as dogwood. Wetland buffered by narrow strip of hardwood trees on south side and wider expanse of hardwoods on the south. Bird spending all of its time feeding within 0.5 m of the water. When startled by our approach, it occasionally flew up into the trees (maximum height 3 m). Weather conditions: Overcast. No precipitation during observation. Wind light from the southeast. Heavy snow throughout the morning had stopped by the time we discovered the bird. Kind of lighting on bird: Excellent. Bird seen from all angles. Lighting diffuse and as long as the bird stayed low with vegetation acting as a background, the colours were saturated and lighting was excellent. Bird stayed low for most of period of observation. Observer’s distance from bird: As close as 3 m. Optics used: Swarovski 10X42 SLC binoculars and Leica Televid 62 mm Apo AN spotting scope with 16-48X zoom eyepiece. Photographs taken: Photos taken with Nikon Coolpix 4500 held by hand to spotting scope objective. General Observations Circumstances of observation: Conducting Fisherville Christmas Bird Count. Bird spotted by Richard Skevington as we were exploring a spring fed creek. Seen within seconds by Jeff Skevington and minutes later by John Harvey. We instantly recognized it as an Empidonax flycatcher and I immediately recognized that it was not and eastern species. The most noticeable diagnostic features that we commented on immediately (and differentiate it from other Empidonax species) were: tail regularly pumped/dipped (as in Eastern Phoebe), long narrow bill with black tip ventrally, narrow complete eyering (with no flaring at the back of the eye), pronounced contrast between back (green) and head (grey), white throat contrasting with pale yellow breast and belly, call a Least Flycatcher-like whit, somewhat softer than Least though. Despite having seen Gray Flycatcher 3 or 4 times before I had not seen this plumage and did not recognize it immediately. The tail wagging behaviour was clearly correct for Gray Flycatcher but the green back and yellowish front was new to me (I had only seen alternate adults before). I ran back to the car and retrieved my spotting scope, digital camera and Sibley. A quick look in the bird book confirmed that we were looking at a first winter basic Gray Flycatcher. I then spent another 30-40 minutes documenting the bird with photographs and notes before we moved on to complete our CBC. Catching small insects near ground and on ground during brief forays. Apparently eating caddisfly larvae in two instances (presumably captured from the water). Description: Immediately recognizable as an Empidonax flycatcher (small, drab, warbler-sized passerine with two wing bars, narrow eyering, narrow insectivorous bill) (Figure 2). Head: Soft grey overall; off-white eyering complete, narrow, consistently the same width (not flared at back) (Figs 2, 4, 5, 6, 8, 9); off-white of lores extending across base of bill (Figs 4, 6, 8, 9); white throat extending into almost complete collar around nape (Figs 2, 7); bill long, narrow, with black upper mandible and predominantly yellow lower mandible (black only at tip contrasting sharply with yellow) (Figs 5, 6). Front: most of breast and belly, pale yellow (Figs 2-9), greenish across breast below throat with faint greenish streaks radiating from this area laterally (Fig. 6); legs and feet black (Fig. 9). Back: From the collar down to rump (including scapulars), a consistent green, contrasting markedly with the grey head (Figs 2, 4, 5, 7, 8, 9). Tail: dark, long for an Empidonax (Fig. 8), with extensive white on outer rectrices (Figs 8, 9); central tips of rectrices sharply pointed as in many first year passerines (Fig. 7). Wing: Feathers predominantly black other than as follows: median wing coverts and wing bar off-white, similar colour to edging on tertials and secondaries, perhaps slightly more yellowish (Figs 2-4, 7-9); short primary extension (Fig. 3). How were similar species eliminated (Note: Kaufman (1990) used extensively for this comparison): Voice: Four similar Empidonax species have whit calls as given by this bird: Least, Willow, Dusky, Gray; six species different and can be excluded on call alone: Hammond’s (sharp peep), Pacific-slope (male gives slurred, ascending peweat), Cordilleran (males similar to Pacific-slope but two-syllabled with second note higher, pit-peet, females of Cordilleran and Pacific-slope give a very thin high-pitched tseet), Yellow-bellied (rising per-wee or preee, a peer on one pitch or a sharp, descending pyew), Acadian (loud peek), Alder (flat peep or kep). Behaviour: Least and Yellow-bellied very active, jerking tail upward and often flicking wings at same time; Hammond’s flicks wings and tail regularly, often at same time; Dusky flicks tail and wings less often that Hammond’s and Least; Acadian rarely flicks wings and tail, often perches with wings drooping; Willow and Alder tend to flick tail and wings mostly immediately after landing. Tail dipping as we observed is found only in Gray Flycatcher and is the most distinctive behavioural trait of any empid, very like Eastern Phoebe - slow, downward swing after which tail is returned to original position. Other species may flick tail down, but these flicks are almost too rapid to see. Gray also flicks wings infrequently (we did not observe this behaviour at all) and tends to perch low and often flies down to take insects on or near ground (as our bird did - but other species will do this in cold weather when insects are low). Bill: narrow and sides straight in Hammond’s, Dusky and Gray (this very distinctive characteristic matches our bird, Figs 2, 5, 8 and 9); broader and slightly convex in Least, Cordilleran, Pacific-slope, Yellow-bellied, Acadian, Willow and Alder; shortest in Hammond’s, short in Least, long in Dusky, Acadian and Gray (as in Fig. 2). Pattern of lower mandible: yellow with dark tip (as shown poorly in Figs 5 and 8) only in Hammond’s, Dusky and Gray, completely yellow in all others; dark tip extensive, over half of mandible in Hammond’s, restricted to tip in Dusky and Gray; dark tip grading into pale base in Dusky and Hammond’s, contrasting sharply in Gray (as in our bird, Figs 5 and 8). Primary extension: short as in Figs 3, 8 and 9 in: Gray, Least, Dusky, Pacific-slope, Cordilleran, Yellow-bellied; long in Hammond’s, Acadian, Alder, Willow. Head: smoothly rounded as in Figs 2 and 9 in Least, Gray, Dusky and Hammond’s; very slight crest in Yellow-bellied, Willow, Alder and Acadian; moderately crested in Pacific-slope, Cordilleran. Pale area on lores present but variable in all species, continuing in pale band across forehead only in Gray (as in Fig. 6). Tail: long in relation to length of wingtips (as in Fig 8) in Dusky, Gray, Least, Cordilleran and Pacific-slope; moderate length in Acadian, Alder and Willow; short in Hammond’s and Yellow-bellied. Tail broad in Acadian, Willow, Alder. Gray with obvious white outer edges on tail (Figs 8 and 9), white brighter and more extensive than in any other Empidonax (Kaufman warns about assessing this in the field but it was a very distinctive character that we all commented on with this bird). Throat colour: white in Least, adult Acadian, Willow, Alder, contrasting with face; grey in Hammond’s (no sharp contrast between head and throat), Dusky, Gray (very pale grey to nearly white, but no sharp contrast between throat and sides of head – Figs 2-9 show a white throat contrasting with sides of head. This is the only char
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