Friday, February 20, 2015

Albany Pelagic Trip Report - 7 February 2015

Summary: This was the first trip run off Albany in February (or any summer month, for that matter) so it was difficult to know what to expect. It turned out to be an interesting trip, with a reasonable variety of seabirds. 9-10 tubenose species were recorded, along with several skua and tern species. The highlights were close views of a large pod of Pilot Whales around the boat, and records of Sooty Tern, Long-tailed Jaeger, and Short-tailed Shearwater. The latter two were not unexpected at this time of year, but both represent the second records of the species for Albany pelagics. The Sooty Terns were more unexpected, and appear to represent the first records of the species off the south coast of WA.

Pilot Whales (suspected Long-finned Pilot Whales) off Albany. Long-finned and Short-finned are barely separable at sea in areas where they overlap. Long-finned is the more likely species off Albany, and the relatively prominent and well-defined pale saddles are also suggestive of Long-finned. Photo courtesy Plaxy Barratt.

Participants: Alan Collins (Organiser), John Graff (Organiser), Plaxy Barratt, Bill Betts, Rose Ferrell, Stewart Ford, Ross Jones, Dan Mantle, Ian Mayer, Peta Moore, Michael Morcombe, Robyn Pickering, Nathan Piesse, George Swann, Peter Taylor, Roy Teale, Peter Valentine

Conditions: Conditions were forecast to be relatively calm, with seas 1-1.5m and swell 1.5-2m. Winds were forecast easterly at 10-15 knts. Conditions were largely as forecast; if anything somewhat calmer.

We departed Emu Point Boat Harbour at approximately 0600. Activity in King George Sound was limited, but several people saw a distant Arctic Jaeger, and the first Flesh-footed Shearwaters began to appear. As we approached the heads, a small group of Common Bottlenose Dolphins was seen briefly. We cleared the heads, but little was seen aside from increasing numbers of Flesh-footed Shearwaters. Eventually, the first albatross was seen, a young Black-browed-type which may have been a Campbell Albatross, but separation of immatures ranges from difficult to impossible. This was followed by an adult Black-browed Albatross, and the first Indian Yellow-nosed and Shy Albatross followed reasonably shortly afterwards. A jaeger was then seen in the mid-distance; the buoyant, tern-like flight style indicated a Long-tailed Jaeger. A second was seen shortly afterwards, but little else was seen until we reached the shelf break.

Long-tailed Jaeger off Albany. The easiest ID feature for separation from other jaegers is the more buoyant and tern-like flight style, but note also overall structure, the white shafts limited to the outer two primaries only, and very limited pale primary bases on underwing. This species is also typically seen well offshore over deep water, whereas Arctic tends to be more coastal. Photos courtesy Bill Betts (top) and Dan Mantle (bottom).

We passed over the continental shelf edge and stopped the boat in 800m of water, and a third Long-tailed Jaeger was seen briefly making a pass over the boat by several people. Indian Yellow-nosed and Shy Albatross joined the Flesh-footed Shearwaters around the boat and the call for whales went out almost immediately, as a large pod of Pilot Whales was seen off the starboard side. Whilst initially quite distant, several groups made very close passes of the boat. Separation of Short-finned and Long-finned Pilot Whale at sea is very challenging and both could occur off Albany, though Long-finned is the more likely species. The relatively prominent pale saddle on a number of the animals is also suggestive of Long-finned. A few people also saw some more triangular dorsal fins which suggested a second cetacean species was present, which has subsequently been supported by photographs – identification has so far proved problematic though. The first White-faced Storm-Petrel made an appearance in the slick, and the species remained present in small numbers at both stops. A Short-tailed Shearwater was also spotted making a pass amongst the numerous Flesh-footed Shearwaters – this was the second record for Albany pelagics, but was not unexpected as the species breeds in large numbers on islands in the Recherche Archipelago off Esperance. Then a group of five terns were sighted off the stern. These were initially assumed to be Bridled Terns, but as they made a pass of the boat, several observers suggested that at least some of them were in fact Sooty Terns. Photographs have subsequently indicated all five individuals were Sooty Terns, a first record for Albany pelagics and quite possibly a first record for the south coast of WA. The first Wilson’s Storm-Petrel for the day was also seen, and another group of Pilot Whales also made a close pass of the boat.

Sooty Tern at the continental shelf edge of Albany – note the broader, shorter white forehead patch and uniform black upperparts for separation from Bridled. Sightings of this species on these trips may represent the first records of the species off the south coast of WA.

Adult Shy Albatross. The very thin dark borders to the underwing, and the ‘thumbprint’ at the base of the wings are useful features for separation from other albatross.

After drifting for around two hours, we relocated a little deeper, stopping the boat in 900 m of water at around 1100. Whilst travelling, another Sooty Tern and another Long-tailed Jaeger were seen. We deployed the second chum block, but the species present remained similar to the previous stop until a Great-winged Petrel was finally spotted amongst the Flesh-footed Shearwaters. A few more individuals made passes throughout the stop. Several more Sooty Terns also made passes, including a pair passing high over the boat. The major interest came when the call went out for a Wandering-type Albatross. Frustratingly, it passed by distantly and did not come into the boat. The frustration increased when photos showed it to be a classic antipodensis (sensu stricto) or amsterdamensis type, with a wholly dark upperwing, dark cap and ear coverts, but largely pale body. Photos even suggest a dark bill tip, so it is very disappointing the bird didn’t come closer.  The final sighting of note was a shark that appeared off the back of the boat – expert opinion is that the dorsal fin shape in photos indicates a Dusky Whaler.

Wandering-type Albatross. This individual shows a dark cap, completely dark upperwing and mostly dark tail, with a pale body – this is a classic plumage of Antipodean Albatross D. [e.] [antipodensis] antipodensis. However, it may also occur in Amsterdam Albatross D. amsterdamensis, though the limited photos available suggest this taxon tends to retain more brown on the lower back and show a reduced dark cap and ear coverts when this white on the body. Photographs suggest this bird has a relatively dark bill tip which is typical of amsterdamensis (but can also occur in antipodensis), but this is difficult to judge with certainty given the distance and lighting – it is particularly obvious in the top photo, but the lower photo suggests it is much less clear. Photos courtesy Nathan Piesse.

Dusky Whaler. In many cases, this species is not confidently separable from Bronze Whaler without dentition details, but in more extreme cases fin shape can apparently allow for separation. Photo courtesy Dan Mantle.

We set off for home shortly before 1400. The return trip was largely uneventful, with nothing new seen, though we did pass a small flock of eight White-faced Storm-Petrels. Two Arctic Jaegers gave good views in King George Sound, and a few Australasian Gannets were also seen. We docked at approximately 1630. Many thanks as always to all the participants, and to Tony and Fred from Spinners Charters for their assistance.

Short-tailed Shearwater – this species is far more common off the east coast but does breed in large numbers on islands in the Recherche Archipelago off Esperance. It has rarely been reported as far west as Albany, but this is likely to be the result of a lack of observers.

Species List (Total count [Maximum seen at one time])

Wandering Albatross sp. 1 (1) – antipodensis (sensu stricto) or amsterdamensis
Indian Yellow-nosed Albatross 18 (6)
Black-browed Albatross 1 (1)
Black-browed Albatross [sp.] 1 (1)
Shy Albatross 10 (3)
Great-winged Petrel 6 (1)
Flesh-footed Shearwater 300 (60)
Short-tailed Shearwater 1 (1)
Wilsons Storm-Petrel 9 (6)
White-faced Storm-Petrel 20 (8)
Arctic Jaeger 3 (2)
Long-tailed Jaeger 6 (1)
Caspian Tern 1 (1)
Crested Tern 5 (2)
Sooty Tern 10 (5)
Australasian Gannet 4 (2)

Pilot Whale 60+ (50+) – probable Long-finned Pilot Whale
unidentified cetaceans 5+ (5) – possibly False Killer Whales
Common Bottlenose Dolphin 4 (4)
Dusky Whaler 1 (1)

Unidentified cetaceans seen distantly with the pilot whales. They may be False Killer Whales but brief views and poor photographs mean that identification is not possible with any confidence. Risso’s Dolphin has also been suggested, but would be expected to show more pale scarring on most animals (not visible at all in the field). It may not even be possible to rule out variation in Pilot Whales with any certainty. Photo courtesy Dan Mantle.

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