ML54921521
Contributor
Date
Location
- Age
- Not specified
- Sex
- Not specified
Media notes
This adult or nearly adult Red-footed Booby was found the previous morning by Dean DiTommaso and photographed here by Curtis A. Marantz on 17 April 2017 as it flew by Ellen Browning Scripps Park heading south down the coast, La Jolla, San Diego County, California.
Observation details
After less than an hour of searching, I spotted this bird just before 8:37 am as it flew in a southerly direction low over the water 300-400 meters offshore as it passed by a flock of gulls that were sitting on the water. This bird flew with a direct, albeit somewhat lazy, flight that combined shallow wing-beats with short glides in a manner that was more like the flight of a jaeger than a gull. I used primarily my 25-60× spotting scope to observe this bird, which was seen in unobstructed view and with the morning sun at my back. I took only one photo before the card filled, so I concentrated on studying the booby through my scope until it passed around the point and disappeared. This was a small and noticeably slim booby that was clearly smaller and slimmer-bodied than the Western Gulls (L. occidentalis) over which it was flying. It also had a slim bill of medium-length that appeared shallower at the base and slimmer throughout than that of a Brown Booby (S. leucogaster), or conversely, much slimmer than that of a Masked Booby (S. dactylatra). The crown was rounded but the head seemed to lack the obvious expansion or almost bulbous appearance that is typical of Masked Booby, and the neck and body both appeared to be quite slim. The wings were likewise slim throughout their length and tapering to pointed tips, but I also thought they were kinked backward at the wrists almost like those of a jaeger, rather than having the wingtips held straight outward. The tail was relatively long, slim, and with the tip apparently tapered even though I could not see if it was pointed or rounded. I never saw the legs or feet. My best views of this bird were from above as it flew low over the water, so even though I saw clearly the underparts, my recollection of the pattern on the underwings is pretty weak. What I could see was that the head, neck, back, scapulars, wing coverts, and underparts were snow-white and unmarked. I noted no buff or yellowish cast to the head or neck. The rump and tail also appeared to be white. I detected what appeared to be a grayish wash to what appeared to be either the rump or the base of the tail, but I was at least moderately confident that this bird lacked black in the tail. Contrasting sharply with the white of the upperparts and wing coverts were jet-black remiges that produced a relatively narrow yet sharply demarcated trailing-edge to the wings that extended from the wingtips inward through both the primaries and secondaries nearly to the body; however, the black that extended through the secondaries tapered to a point just short of the body. As such, the innermost remiges were white like the coverts, though I could not be sure if these represented only the tertials or both the tertials and the innermost few secondaries. I thought the primary coverts and secondary coverts were entirely white, which resulted in the black on the wings being restricted to the tips and trailing edge as opposed to the solidly black wingtips of Northern Gannet (Morus bassanus), but my single photo suggests the primary coverts at least were black, so the extent of black on the upperwing appears more extensive in my photo than I had remembered from the field. My impression was that the pattern on the underside of the wings was similar to that on the upperside, but I had a hard time seeing much detail. I did not notice an isolated spot of black on either the uppersides or undersides of the wings, but I am more confident that I would have seen it on the upperwings had it been there. My impression was that the bill was either light blue or light gray, and I am confident that it was neither yellow nor orange. I am not sure I ever detected pink tones to the face, yet I am confident that the unfeathered face did not contrast as sharply blackish against the white feathering that bordered the face or the pale bill.
Technical information
- Model
- Canon EOS 7D Mark II
- Lens
- EF100-400mm f/4.5-5.6L IS II USM
- ISO
- 320
- Focal length
- 400 mm
- Flash
- Flash did not fire, auto
- f-stop
- f/8.0
- Shutter speed
- 1/2000 sec
- Dimensions
- 604 pixels x 430 pixels
- Original file size
- 103.66 KB