Juvenile Pomarine Jaeger in Barrie

2, 3 and 4 November 2005, Scroll down for 8 photos.

I appreciate input from Kevin McLaughlin, Brandon Holden and Ron Pittaway.

This Pomarine Jaeger was chasing the Bonaparte's and Little Gulls on the waterfront in Barrie on 3 November 2005.

4 November 2005

Pomarine Jaeger showing the underwing while chasing a Bonaparte's Gull.

Dark area divides small whitish crescent at base of underwing primary coverts with larger white wing flash creating double pale highlight.

Pomarine Jaeger and Herring Gull on 2 November 2005.

Pomarine Jaeger Identification posted on Ontbirds on 3 November 2005

Kevin McLaughlin calls it a typical "brown morph" juvenile Pomarine, the commonest form. He notes the overall look is the key and is made up of a number of points (see below) which do not support its identification as a Parasitic. Ron Pittaway and I have added some comparisons of Parasitic in (parentheses) to Kevin's analysis of the photos.

- cold brown plumage in Pomarine (rusty feather edgings in most Parasitics)

- thick chested; size next to Bonaparte's Gull impressive

- may have seven white primary shafts (fewer in Parasitic)

- short rounded projection of central rectrices (pointed central tail feathers in Parasitic)

- broad based wings though not really obvious

- broad white flash on bases of under primaries, but only a bit of white on the bases of the greater under primary coverts; wear may be a    

factor (see paragraph below)

- stark white and brown barring on the undertail coverts along with whitish uppertail coverts (upper and undertail coverts less clearly barred in

Parasitic)

- no obvious streaking on the nape (head streaked on Parasitic)

- dark loral area an excellent feature as it contrasts to the pale bill base

- bill base is thick, but not overly so

- remnants of whitish tipping on the coverts and no suggestion of whitish lines on the outer web of the greater coverts

- absolutely no pale or tawny crescents on the tips of the folded primaries (as in Parasitic)

- although looking rather "soft", the under wing coverts seem dark and white barred

Ron Pittaway and I studied the Pomarine closely for several hours on Thursday, 3 November 2005. Although not obvious in the flight photos, we several times noted the double pale highlights on the underwings including the white area on greater under primary coverts which were more evident when backlit Many birders expect Pomarines to be bigger, but without direct comparisons with other jaegers their larger size and heavier bill are difficult to judge. However, its much greater size when pursuing Bonaparte's Gulls was apparent. In jaegers, females are slightly larger than males.