Sunday, August 31, 2008

Coral Bay experience (5) - The leopard whipray - update

Shadowkiller got back to me with the ID of this whipray - he said this is a reticulate whipray (Himantura uarnak), not a leopard whipray (Himantura undulata) as mentioned in my previous post. According to him, a juvenile reticulate whipray has three rows of spots before its sting; this agrees with the description in Sharks and Rays of Australia (PR Last & JD Stevens, CSIRO Australia, 1994).


Based on the information about these two whipray species that I have gathered so far:

Distribution:
  • The reticulate whipray is common in the waters of northern Australia between Shark Bay (Western Australia) and Brisbane (Queensland); the leopard whipray between Ningaloo (Western Australia) and Torres Strait (Queensland). So it's likely to find both species in Ningaloo.
Color pattern:
  • Juveniles of both species have dark spots on their bodies, but they can be distinguished based on the following features:
  • (1) The tail of a juvenile reticulate whipray usually has three distinct rows of spots before the sting. Also, it has more than five (usually seven) spots in a direct line between the spiracles.
  • (2) The tail of a juvenile leopard whipray usually has one row of spots on each side before the sting. Also, it has two or three spots between the spiracles.

Based on this photo, it is not easy to determine the number of spots between the ray's spiracles. But they certainly look like more than two or three.

Wednesday, August 27, 2008

My pink coral and strapweed photo on another website : )



No, nothing to worry about really. Not e-piracy or anything like that.

A couple of weeks ago, a documentary producer who saw my photos on the Marine PhotoBank website asked if she could use my photos on her website. I was quite happy that others like my photos, so I said yes. She put up my photo of pink corals and strapweeds, which I took this February in Parker Point Marine Sanctuary of Rottnest Island. You can check out her site here. You can also find a larger version of the photo here.

Monday, August 25, 2008

Coral Bay experience (8) - Red firefish (Pterois volitans)


My encounter with such a beautiful red firefish (Pterois volitans) was probably a compensation for my slightly frustating Manta tour in the morning. This fish usually hides itself in caves or under ledges during the day, with its head pointing downwards just like in this photo. So, I must be really lucky to spot it in a 1 meter deep water and just 10 m or so from the shore. And what's even better was that it just won't bother to run away and I managed to make a short clip of it and took a few photos too. Unfortunately, it was late in the evening and the light condition was poor and the water was not calm enough. And I tried not to get too near so that I would not frighten it away or get stung! Well, I found the quality of the images really poor when I returned to Perth. Only the photo shown above is still reasonably presentable. What a shame!



Well, about the frustrating Manta tour and the rest of the day:

On my Day 4 in Coral Bay, I went on a Manta tour, which took me and nine others to Bateman Bay, situated in the north of Coral Bay. To make a long story short, a manta ray was spotted and everyone jumped in and went after the animal. Unfortunately, it just won't slow down. And I gave up after I caught a glimpse of it - from a distance in the rather turbid water. What an expensive glimpse! And to make it worse, I started to feel seasick while sitting on the boat waiting for others to return. For the second part of the tour, we were taken to the outer reef to snorkel. And I was told that I was a lousy snorkeler - my kicks being entirely wrong and noisy etc. Not that I ever pretend I am good anyway.

And when I returned from the tour I decided that I would just stick to the shore. So in the afternoon, I took a 60 minutes' walk from the backpackers to the Five Fingers Reef, which is right next to the southern boundary of the Maud Sanctuary Zone. (FYI, Coral Bay is within the zone.)

Joining a tour to snorkeling sites was not as flexible as going on my own. So I walked. I could have hired a quad trek I guess, but I have no Aussie driving license. Walking was painful or mostly so during my stay in Coral Bay. I hurt my left foot the week before I went to Coral Bay. So, I could only walked at half my normal pace most of the time. And the way I walked was really awkward; I almost looked like I was limping along. Sometimes, I had to stop and just stand still for a minute or two when it got really painful. Anyway, when I snorkeled the pain seemed to have disappeared. I suppose when you snorkel, you don't stress your sole that much; and the cold water might be helpful, I guess.

Anyway, after 60 minutes' walk, I found that I didn't want to snorkel at the Five Fingers Reef. The water just didn't seem nice - my gut feelings. And well, also because I had a fall when I tried to take a closer look at the small barnacles on the slippery rock. Nothing major except I somehow jammed my little finger really hard into the rock and it turned almost blue and my finger nail felt like it would fall off anytime. And my underwater camera hit the rock when I fell!


The Five Fingers Reef beach - the rocks on the right extend to the sea and form one of the fingers I think.


One of the finger reefs - the spot where I slipped and fell.

So, I left the Five Fingers Reef and snorkelled northward from the southern end of the Maud Sanctuary Zone instead. Within 5 - 10 minutes after I hit the water, I bumped into the red firefish!

That evening, after I saw the red firefish, I thought Well, never mind the lousy day, I saw a beautiful fish. But I didn't know then that most of my photos of the fish would be poor as well.

Sunday, August 24, 2008

The South Cottesloe Beach at different times of the year

When I first visited the South Cottesloe Beach last November, I decided that I should document, using photographs, the changes on the beach (and hopefully underwater) at different times of the year. It was supposed to be an interesting project - not really a scientific one, but one that would give me another reason to visit the beach frequently. And I did visit the Cottesloe beach quite diligently - on average 3 times a month between last November and today!

It has been more than six months now. So I thought I would write a post about it.

To keep track of changes on the beach, I have taken photos from or at four points on the South Cottesloe Beach, as indicated in the above mud map. For a decent map of the Cottesloe Reef Fish Habitat Protection Area, you could either google for it or go here.


Looking south from the Cottesloe sundial (position 1 in the mud map) - February (left) and August (right) this year.

In summer months, this part of the beach was very often deserted if you ask me. You might see some snorkelers but not the surfers or stand-up paddlers. The shore would be covered in sand (left). In winter months, very often I saw a rocky shore (right). And in the photo, you can see green algae on the rocks at the water's edge. Also, in winter, there were very often seagrasses and seaweeds that were washed ashore (not in this photo). And you would see many surfers in the water :)


Position 2 in the mud map - photos taken from the steps - November 2007 (left) and May 2008 (right).


Position 3 in the mud map- photos taken a few steps from the beach sign - February 2008 (left) and July 2008 (right). Again, sandy shore in summer, rocky in winter. I suppose seagrass wracks were common at both times but the rocks and the algae that grew on them were only common in winter.


Looking north from position 4 in the mud map towards the second rock - June (left) and August (right) this year. I call it the second rock because I can't find its name - and not even sure that it has one. Anyway, there were piles of wracks and some sharp rocks in June, but now, it is just clean, sandy shore.


Looking south from position 4 in the mud map towards the Port of Fremantle - June (left) and August (right) this year. Again, lots of wracks in June (I remember seeing them at least two, maybe three weeks in a row) but they are gone now.

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Well, that's why I would never be bored of going to the beach, they just never stay the same. And it is fun to observe how things change on the beach throughout the year. So, I think I will continue doing it till end of the year.

It would have been even more fun if I could keep track of the underwater seascape during the year. Shallow seascape, of course, considering I am only armed with a mask and a snorkel! But that would be a mini-project for future - if feasible.

Saturday, August 23, 2008

Coral Bay experience (7) - Other fishes

On my second or third day in Coral Bay, my chances of seeing more colorful fishes improved when I began to wander towards the southern boundary of the Maud Sanctuary Zone.


On day one, I saw a lot of these - dark-colored fishes - and I still could not find their name(s).


Then when I began to wander away from the main beach, I began to see some blue fishes that hung around branching corals. The blue fish is probably the black-axil chromis (Chromis atripectoralis). This fish has a black spot at the base of its pectoral fin, which distinguishes the fish from a very similar blue-green chromis (Chromis viridis).


And a wrasse (middle?) and a parrotfish (right, near top) too.

Note (31 August 2008):
Shadowkiller came to my rescue again!
According to him, the orange/yellowish fish in the middle is an orange blue-barred parrotfish (Scarus ghobban). And according to Allen & Swainston's book, this is a female. Wikimedia has a nice image of this fish. The Aussie Museum Fish Site has a page about this species too.


The bigger guy is a male Schlegel's parrotfish (Scarus schlegeli). The fish can be recognized by two yellow patches below its dorsal fin. The rear yellow patch forms a narrow bar that connects the dorsal and anal fin.


My first thought was: Arghh... ugly fella! Sorry, Mr or Miss toadfish.
This one is a stars and stripes toadfish (Arothron hispidus). An excellent photo of this fish can be found here.


I have seen goatfishes quite often when I snorkeled in Perth. So I am sure this one is a goatfish - probably an Indian goatfish (Parupeneus indicus). Both the Indian goatfish and blackspot goatfish (Parupeneus signatus) have a black spot on the tail base. But the stripe patterns in their heads differ. It is always fun to see a goatfish stirs up the sand to look for food, but this one worked it quite hard I think - it looked like it just jammed its head into the sand.


This one is a narrow banded sergeant (Abudefduf bengalensis). Unlike the banded sergeant (Abudefduf septemfasciatus) , which looks extremely similar, the narrow banded sergeant has a tail with rounded lobes. This fish is quite common in the shallow waters of the Maud Sanctuary Zone.


And this is another fish that I saw frequently enough in Coral Bay, although not in a big school - the smooth flutemouth (Fistularia commersonii). It is easy to remember because it has a long snout. This fish differs from the rough flutemouth (Fistularia petimba) in color, the latter is reddish or brown. All the ones I saw were the smooth flutemouths. I haven't bumped into any rough flutemouths in Coral Bay.

And it swims like a snake! Check out the short clip below. I took the clip when I was snorkeling on the outer reef. The fish was probably 50 cm or so in length.



Reference:
The Marine Fishes of North-Western Australia, by Gerald A. Allen & Roger Swainston, published by Western Australia Museum, 1988.

Also, thanks to Shadowkiller of the Dive-Oz forum (again), who ID Scarus schlegeli and Arothron hispidus for me!

Thursday, August 21, 2008

Coral Bay experience (6) - Fish feeding / Spangled emperors

These videos and photos were taken during a fish feeding session in Coral Bay. I can't remember who does it but fish feeding is done every afternoon at half past three, near the boat ramp.

The day I went to watch fish feeding, I found that 10 minutes before the feeding would begin, the fish (mainly the spangled emperor) were already waiting very near the shore. Equally excited about the feeding session were the people who arrived early. The person who fed the fish was probably the only one who arrived last.





Days ago I commented in a post that the spangled emperor is so friendly and not camera-shy at all. Now I think the fish's behavior may have been conditioned by their interaction with people during the fish feeding session. So, when the fish saw me underwater, it might have thought Is he going to feed me or what?



I remember Denis asked whether this fish makes good eating a few days ago. "The Marine Fishes of North-Western Australia" by Gerald. R. Allen and Roger Swainston (Western Australian Museum, 1988) says this fish which can grow up to 86 cm in length and 6.5 kg makes "excellent eating".



Tuesday, August 19, 2008

Lost baby humpback whale in Sydney

I wonder if you have read about the lost baby humpback whale in Sydney.

Link to The Australian.
Link to ABC News.

It is so sad just to read about how the baby whale hasn't feed for probably 4 days and was getting weaker, that it might not survive many more days, that it just couldn't get into contact with whales nearby or join them after it was lured back to the open sea, and to hear the news video on ABC News website says that "euthanasia is probably the kindest thing to do".

Sunday, August 17, 2008

Coral Bay experience (5) - The leopard whipray

Stingrays! My favorite underwater model. They are beautiful enough when they are still, even the ones with plain colors. They are so graceful when they flap their fins, like a giant bird flapping its wings in slow motion.


This one is possibly a leopard whipray (Himantura undulata). I saw it near the shore, in water that was only 1 meter deep. It was covered in sand and I almost missed it.




The upper surface of its body, including part of its tail, is covered in a of pattern of dark blotches resembling that of a leopard's fur. And if you look carefully, you can see the spine on its tail. This one has one spine, typical of a leopard whipray.


Initially I thought this is Himantura uarnak, also known as coachwhip stingray or honeycomb stingray. It does look similar to the picture of H. uarnak in "The Marine Fishes of North-Western Australia: A field guide for anglers and divers" (Gerald R. Allen & Roger Swainston, 1988). Later, my friend Steve told me that it might be Himantura undulata (leopard whipray) according to "World Atlas of Marine Fishes" by Rudie Kuiter and Helmut Debelius. Well, the first book doesn't have any info about leopard whipray.



"Field Guide to Australian Sharks and Rays" by RK Daley, JD Stevens, PR Last, and GK Yearsley (2002) says that the adult leopard whipray can be confused with the coachwhip stingray (H. uarnak) and these spesies are not easy to ID. The Georgia Museum website says the same thing. Anyway, since this stingray fits the descriptions I could find about leopard whipray (e.g. leopard-like spots even on part of the tail, very long tail, only one spine, found in the Ningaloo Reef Marine Park), I will assume it is a leopard whipray.



On the spot, I estimated its tail to be about 5 times its main body length!

In fact, after my encounter with this stingray, I began to think that one good way of looking for a stingray like this one is to look for any unusual-looking, long stick on the sandy floor - its tail. This fish moved a couple of times during "our" photography session, but I noticed that while the fish's body could be covered in sand for camouflage, the tail was usually exposed.

Other references:
A little guide to stingrays by Nigel Marsh
www.austmus.gov.au/fishes/fishfacts/fish/hundulata.htm

Saturday, August 16, 2008

Coral Bay experience (4) - The green turtle

I saw the green turtle (Chelonia mydas) twice. The first time I saw one I was heading back to shore at Paradise Beach, Coral Bay, cold and hungry after two hours in the water. The second time I saw one I was snorkeling in The Lagoon, a snorkeling spot which is accessible by only 4WD or quad trek bike.


The turtle I saw had a carapace (shell) consisting of five central scutes (bony plates)(A-E) flanked by four scutes on each side (1-4). This characteristic fits the Wikipedia description of a green turtle. I just couldn't see the turtle's snout and its underside, so I couldn't confirm its identity further. But the colors of the carapace also suggest that it's a green turtle.


It was exciting to bump into it because it was an unexpected encounter. The water was only about 3 m deep where I found the turtle and I was probably just 30 m from shore.


The green turtle gets its name because its fat is green and is more evident when the animal is boiled up into soup ("The Marine Life of Ningaloo Marine Park & Coral Bay" by Ann Storrie & Sue Morrison, 1998).

The Shark Bay World Heritage website says this:
"... the species actually gets its name from the colour of its fat. People know what green turtle fat looks like because the turtle was hunted in Australia for its eggs and meat – which was boiled into soup – until it was given legal protection in 1973."

And the animal's green body fat is believed to be due to consumption of lots of seagrass and algae (Ref).


I was swimming above it for a while, maybe a minute or two.


The turtle in this clip was the one I saw on my way back to the shore. It swam to the surface for air and dived down again. It used mainly its front flippers and the back flippers hardly moved at all.


The turtle in this clip was the one I saw in The Lagoon. When I first saw it, it was grazing on some seaweed or seagrass on the sea floor. In the second half of the clip, you can see a fish that kept tagging along with the turtle.

Thursday, August 14, 2008

Coral Bay experience (3) - Giant Clams

These giant clams, or rather their mantles, look so beautiful! And they are easy to photograph too! Unlike the fishes, these won't run for their lives when you get near them.












The giant clam is everywhere around the coral reef. I am not even sure that I have taking photos of all different mantle coloration or patterns there are to be found in Coral Bay.

Wednesday, August 13, 2008

Coral Bay experience (2)


Looking south from a sand dune into the main beach area and the boat ramp of Coral Bay. In the south of that yellow sand is the Paradise Beach. The white line near where the ocean meets the sky marks the outer reef.


Spangled emperor (Lethrinus nebulosus) - blue lines on the cheeks and blue spots on the scales - that is basically how you can tell this one apart from its similar looking relatives. More info is here.

I saw many of this fish when I was snorkeling near the main beach. The great thing about them is that they would swim to you and around you, without showing the slightest sign of being camera shy. Maybe they were simply "inquisitive" - a word that many marine life writers like to use. Most of the ones I came across were probably 2 feet or longer.


Left: Another spangled emperor with an encrusting sponge or just corals in the background.
Right: Blue-tipped staghorn corals (?)


The giant clam (Tridacna species) was everywhere. I just learnt that the pretty patterns on the mantle are contributed by some microscopic algae living within the mantle tissue. This reminds me of the symbiotic algae living within the bell of the white-spotted jellyfish and the ones within corals.


Corals whose names I don't know.


Bleached patches in a coral colony


This brown one that looks like a blanket has very pretty pinkish, purplish edges.



These rock melons (except for one) are the brain corals (Platygyra species).


Another one whose name I don't know.

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