Terns are amongst the most elegant of birds. Long sickle-shaped wings and unhurried flight contribute to their aerial grace. Even on the ground they seem to squabble less than other seabirds, spending their time bathing, preening or sleeping with beak tucked under a wing.
Crested Terns bathe daily to keep their plumage in good condition. The bath takes place in shallow water such as a rock pool. Bathing terns generate huge amounts of spray as they flap their wings and duck their heads.
At the end of the bathing session terns hover for a second or two just above the water to dislodge droplets from their plumage. The hover turns into directional flight. Terns will often quickly decide they aren’t dry enough, at which point they shake violently while continuing to fly forward. They will often complete a barrel roll before spinning back in the opposite direction. It makes for some of my favourite ‘bird in flight’ shots, the normal elegance of the tern replaced for just a moment by the ungainly shimmy and shake.
Grey Nurse Shark
Grey Nurse Sharks are known to congregate at certain sites on the NSW coast. Some sites attract breeding aggregations, while others act as day time ‘refuges’ where the sharks can spend the day in relative safety. Aggregation sites are commonly at the base of abrupt reef walls with deep overhangs or amongst a set of sheltered swim-throughs and gutters. During the day the sharks act as though they are on autopilot, repeatedly swimming a set route around the site. They will respond to the presence of a diver, especially if you approach too closely, by altering their direction enough to avoid the intruder. At night they become more active and head off in search of food.
One of the best known places for seeing Grey Nurse Sharks is Magic Point off Sydney’s eastern suburbs. The Magic Point sharks were typically juvenile females of around a metre and a half in length. The site has been visited by thousands of divers over the last two decades, during which time there were almost always a few sharks present. That was, up until a few months ago, when the Grey Nurse Sharks disappeared from Magic Point.
I haven’t yet heard a convincing explanation of what triggered the departure from Magic Point and it may well prove a temporary phenomena. Nonetheless, in what could be purely coincidence, a new aggregation site has recently been discovered to just to the south of Sydney. The new location is at the end of a large wharf. It has been a popular diving site for decades, and a consequence there is no doubt that the sharks have only just taken up residence. Interestingly, just like Magic Point, the Grey Nurses at the wharf are all juvenile females.
We arrived in pouring rain. It is about a ten minute swim out to the end of the wharf. The steel piles on either side of the wharf are about 15 metres apart, and the visibility was good enough that we could just see from the closest pile to the one opposite. We floated at the base of the end pile and within seconds spotted the first Grey Nurse.
If you chase after the sharks they simply retreat into the gloom, whereas if you stay still they soon ignore you and resume their repetitive loops around the piles. There were at least six sharks. After a while you start to recognise individuals from the pattern of spots down their flanks, the ragged edges to fins or in one case a gash near the mouth that looked suspiciously like the result of a fish hook.
It is always a little confronting how large sharks can appear suddenly from out of the gloom. Those sudden appearances are helped by the Grey Nurse’s ability to slip through the water with little apparent movement. There is no vigorous thrashing of the tail, but instead a subtle shimmy of the flanks that effortlessly propels the shark through the water. The shimmy effect is heightened by the metallic lustre of the shark’s skin, which breaks up the outline of the shark and incidentally plays havoc with camera autofocus systems. The easiest workaround is to lock focus on something at about the same distance, point the camera back to the shark and hope for a sharp image.
After taking a few shots of the sharks I headed away from the piles to investigate the heaps of debris that has been tossed off the wharf. A big metal cylinder provided shelter for a large Red Lionfish. Lionfish have elaborate and colourful fins. The bright colours advertise the fact that each fin is tipped with venomous spines, making the fish a painful mouthful for any predator. The outsized pectoral fins serve another purpose, namely to herd smaller fish into a position where they can be captured with a lunge forward. When a potential threat such as a diver comes near lionfish they tend to spin around so the poisonous tips of the spines face the perceived danger. It can take a few circuits of the merry-go -round to get a head-on shot, but the glittering patterns created by those big pectorals makes it well worthwhile.
Three variations on the theme of shimmer and shake. Perhaps it’s a thin thematic thread to link a seabird, shark and fish, but three pretty amazing examples of Sydney wildlife.
Odds and sods