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California Academy of Sciences - Seahorse Sleuth 

June 30, 2009

Back to Freo

From the Log of David McGuire, Field Associate

Down but not out, we drive from Jurien Bay to Perth and enter the lower reaches of the Swan River, the major tributary that runs through this city of a million people. The team seines in the shallows of the river and a few sleek, green pipefish of the genus Stigmatopora are caught in the mesh nets, but no seahorses.

Undaunted, we relocate and in the waning light Healy and Norah snorkel the cool 60 degree water and find two Hippocampus subelongatus for a small fin clipping and camera cameo.

Research diver

The next day is our final dive and our friend Kevin meets us to investigate another dive at the ammo jetty. The inclement sea prohibits this, so we SCUBA the Swan River near where we had visited the day before, diving in a mild current at 4 meters depth. Success visits again as Graham spots several more H. subelongatus rooted among the sponges and anemones on old boat moorings. We use this opportunity primarily for the video since the team already has a large selection of tissue samples from this species, but the large sample size may help with a population study. In the clear waveless water of the Swan, the images of free-living sea horses are the first clear images I have captured in two weeks of searching. The images from this expedition, last years New Caledonia voyage and others will be used for the public floor at the California Academy of Sciences like the Science Now exhibit, web videos and an expedition documentary in progress. I’m a bit happier to collect clear images of sea horses in the wild but the over all effort has been discouraging: however that’s field science and nature filmmaking.

Researcher using microspcope

Drying gear, repacking and returning the Apollo back to the rental silo (after removing a small beach of sand from the interior) consume the rest of the day. The evening is reserved for keying out fish, including Kevin’s careful morphometric measurements to identify the Shark’s Bay pipefish as the rare species endemic to that region of Western Australia and rarely collected.

It has been a fortnight of travel and diving and the team dissembles, Healy and Norah to the Museum of Natural History at Melbourne where they will confer with their colleagues and Norah will gain more expertise in the morphology of the fish.

Pipefish

The difficulty and the exertion in sampling and filming marine life is a unique challenge, at times exhilarating but also occasionally disappointing. Sea horses and their kin are being harvested intentionally for the aquarium and medicinal trades, and incidentally as bycatch in the shrimp and bottom trawl fisheries. Important habitat is also being diminished and many species are endangered worldwide. Aside from the wonder of exploring and explaining biodiversity, describing what animals live in a region and how they are related is essential information for wildlife management and resource protection. This is one of the important functions of Natural History Museums like the California Academy of Sciences. With new DNA sampling techniques very few animals are sacrificed for the collections and most are set free with a tiny bit of skin missing.

specimen0   Photo by Graham Short

specimen1   Photo by Graham Short

specimen3

specimen5   Photo by Graham Short


Filed under: Uncategorized — hhamilton @ 4:38 pm

A blessing and a curse: Technology in the Outback

From the Log of David McGuire, Field Associate

The southern storm hits us with gale force winds and heavy showers so we hunker down and catch up with work on our laptops. It’s amazing how dependent on communication we have become. Graham has been plugged in most of the way via a wireless card through his cell service, and nearly all the Caravan parks and small towns have wireless. The clicking of keyboards is a constant companion on the journey. Expeditions used to take us away for weeks at a time but now we can follow the protests in Tehran while watching Kangaroos scamper into the bush. Norah is from the plugged in generation and connectivity is second nature, but I’m of the era that exploring includes a separation from constant communication. But I am equally guilty and I suppose this blogging from the field is ironic (if not hypocritical). Nevermind.

Researcher using laptop


Filed under: Uncategorized — hhamilton @ 4:21 pm

Shark Bay but no Sharks (or sea horses)

From the Log of David McGuire, Field Associate

After speaking to a local Aussie who has been here a week, we camp at the pull off below the lighthouse. Lighthouse Bay is a narrow bay fringed by Ningaloo Reef just south of a series of tall Naval Radio towers. The reef extends into a smaller bay that has all the potential of a left hand southern hemisphere Malibu wave breaking on the coral reef flats.

Sea turtles nest here and our local friend said he observed what sounds might be a Loggerhead turtle laying eggs. We dove the outer reef after kicking nearly a kilometer offshore with the strong offshore wind, bottoming out in about 7-8 meters. No pipefish or sea horses observed here but there are lovely corals and diverse fishes including reef sharks, huge potato groupers, sea turtles and a palette of wrasses and soft corals. The kick against the current created by the offshore wind took nearly an hour and we crawled up the steep sand beach face like tired sea turtles after a long swim.

Exempt from city lights the stars are infinite and the Southern Cross and Magellan Kite are clear among the myriads. There are so many stars that our evening beach walk is lit by the star shine of the Magellanic cloud.

In the evening the wind has switched from the east to a stiff northwest and the boat dive we scheduled has been canceled. I was hoping to film the whale sharks that make this area famous for tourism, but the conditions did not allow.

Tantabiddi. Norah and I kicked out half a kilometer to the moored boats and dropped down in 4 meters. This bay looks like it is scoured by tides, although this is the neap tide of the lunar cycle, we still had a 3 –4 knot current: unlikely conditions for our animals to inhabit.

Wake of charter boat

The following day, we chartered a boat from a local fisherman who took us out to some small islands- the Rivoli- in the gulf of Exmouth. The currents and short chop of the shallow bay kicked up the sediments and we ended up moving to another site after an hour of diving. Our skipper, Ash, is quite a character and being height challenged, he sits on the overhead canopy for better visibility of the water ahead while steering with his feet. The second dive was silty and surgy with a building south swell making inspecting the coral ledges and patches of seagrass difficult. Again, none of our target fish were seen. Offshore the whale sharks ply the plankton, but we head inshore for another dive on the fringing reef called the Labyrinth where a dive master informed us they have seen ghost pipefish.

Norah

I would like to put a camera on Norah’s head. As my buddy, she swims ahead of me so I can monitor and film her as she searches, but she has seen several sharks, all quickly out of camera range by the time I come alongside. To me sharks are as attractive as seahorses and unfortunately, are threatened by many of the same influences: killed as bycatch, loss of habitat and targeted by the Asian luxury animal trade. On this dive I don’t see a shark or a seahorse, but an increasing surge from a building south swell. We scout the Exmouth Jetty that Dr. Allen Dekelboum -a longtime Academy associate and Dive Doctor- told us was an incredible dive location. The strong swell and heavy winds did not allow us to test the locale and we headed to deeper water.

The final dive of the day we drift off the anchor in several knots of tide at 20 meters over what is termed the sponge garden. Captain Ash must have missed the location because we see few sponges and the bottom looks scoured and barren with patches of small coral clinging to the substrate. The habitat and conditions are decidedly seahorse unfriendly. This bay has a history of intense bottom trawling for prawns and the fleet is still quite active. The fishermen claim that seahorses are recovered in the trawl nets and Healy made contact with their fisheries manager about sharing specimens. All bycatch is required by the fisheries to be discarded so Healy hopes to work through the permit process to obtain a few bycaught seahorses and pipefish from this region.

We have been diving for over a week now, underwater collectively for sixty hours searching hard but other than the Shark’s Bay specimens we have had little luck. Several of the species we seek have been reported by both our colleagues and in the literature so it is a mystery why we cannot locate the animals in some of the areas where we find ideal habitat.

Discouraged by the weather, and with limited time remaining, we decide to head south. Driving the long open road I count ten kangaroo carcasses in a kilometer but I am yet to get close enough for a good full frame image on my camera. These animals are quite shy, yet inexplicably are attracted to the road. Similarly the Emu, a large flightless bird much like an ostrich. We nearly run one of these huge animals down at sunset, narrowly missing another roadside carnage. Anecdotally, I am impressed by the absence of large predators and only large ravens and the occasional eagle feed on the roadkill. Australia once had a marsupial lion and wolf but those are long extinct and it is up to introduced animals and the automobile to prey on the large herbivores.

Emus

First stop, Kalbarri: a large forested area of rolling hills that most Australians would call mountains. This remnant of the ancient southern supercontinent of Gondwana is eroded and whittled down by eons of time. The road meets the beach at the mouth of the Murchison River, and again a rough unruly ocean meets our gaze. But we’re here to meet with Mike and Wendy, a couple that run the Sea Horse Sanctuary, a seahorse husbandry operation that supplies animals for the aquarium trade, thereby taking pressure off of harvesting of wild seahorses populations. Mike and Wendy are biologists that have been quite successful in breeding several species of seahorses as well as two colorful and charismatic species of pipefish. After a tour of their educational exhibits, they give Healy several specimens: Hippocampus angustus from Exmouth Gulf, a species of seahorse new to Healy’s DNA studies, and two species of pipefish imported from Indonesia.

Seahorses in aquarium

Seahorse Sanctuary

From Kalbarri we press on to try to and dive in Jurien Bay, a large natural bay several hundred kilometers north of Perth. Jurien Bay is the newest marine park in West Australia. All along the section of coastline we have touched upon protected areas. Like California, Australia’s marine parks are managed as a blend of levels of protection, with some areas permitting recreational fishing and other extractive activities, to “fish sanctuaries” allowing no fishing at all. Conversations with locals indicate that many areas have has been overfished and they welcome the protections, while others begrudge the closures.


Filed under: Uncategorized — hhamilton @ 4:11 pm

Lighthouse Bay, N.West Ningaloo Reef WA

From the Log of David McGuire, Field Associate

Driving at sunset the red dirt and the red light makes the landscape feel like Mars. The road is littered with the carcasses of Kangaroos and the occasional Emu and the ravens and eagles dine on the road kill. Now at sunset we see many kangaroos at the roads edge and some standing statue-like in the road and we must carefully avoid running them down. Like deer, the Kangaroos dart across the road at night and most of the vehicles have “roo bars” to avoid the serious damage a large kangaroo can inflict on a vehicle (not to mention the Kangaroo).

Kangaroo carcass

Here in the Antipodes it is close to the winter solstice and the twilight casts a low red glow for nearly an hour, guiding us through the Roos and into Coral By, the entry point to the tourist Mecca of Ningaloo Bay. Here we camp in our first Caravan Park among the gentry of the camping set, replete with power, hot showers, an internet café and watered lawns. The park of over 200 sites is full so we are guided to a small spot off the grid: no power but we revel in the first fresh water showers and first salt free towels since Fremantle.

The next morning we rent kayaks and set off to explore the outer reef. Most of this area is a marine park, Australian’s term for protected areas, but much of the area allows recreational fishing. Our permit allows us to collect in Sanctuaries but we are still careful to paddle out beyond the no take zone. The reef is more diverse and we freedive the coral bommies for our target species but again no luck.

After the kayak excursion out to the fringing reef we packed the combi and headed north along the narrow highway. The landscape is vast and flat with a low green scrub and dotted with red termite mounds resembling islands of life in an otherwise featureless terrain. 150 kilometers further north and we arrive in Exmouth, the heart of the Ningaloo tourism but a heartless looking place with new developments and harbors and tourist signs advertising whale shark tours at every corner. Stopping at the dive shop for information and air fills we exit town and head away from the strong east winds to the lee of the west side.


Filed under: Uncategorized — hhamilton @ 3:43 pm

Carnavaron – Coral Bay

From the Log of David McGuire, Field Associate

Passing the 24th Parallel towards the equator we are nearing the tropics and the land here is rich and green with large sand washes and dry riverbeds indicating torrential rains. The jeeps all have snorkels and the road crossings are posted with depth meters for the heavy rainfalls when the summer monsoon visits. In the hamlet of Carnavaron we met with a local biologist Adam and Photographer Brad Cox, employees of the local water board, but both are avid divers. A former research biologist, Adam has collected seahorses and pipefish throughout the area.

Researchers with maps

With their help, we were able to pinpoint a few likely locations on our map. Adam directed us out to Point Quobba, 60km northwest, where we camped near a weathered rock promontory with powerful surf and blowholes effervescing like whale spouts into the sky. At dawn, biology mirrored geology as six Humpbacks spouted and breached beyond the point.

Seeing humpback whales

The water is much warmer here and the tropical influence is evident in the marine fauna. Our morning snorkel on the inner reef revealed Parrotfish and wrasses not seen farther south, but aside from a few reef sharks and some colorful coral heads, the team observed no study animals. At 11 we met Adam back in town and he generously took us out to the sea grass beds in the yellow submarine, a hard plastic inflatable boat. Adam had previously collected sea horses out on the shallow sea grass beds outside the dredged harbor. Dugongs and turtles also live in the shallow waters in the summer months, but after a few hours the only animal of note was yellow-banded sea snake swimming in the dense sea grass. Struck out again.

yellow_boat

Watering up and renting some tanks and weights from Brad, we motored another few hundred kilometers up the coast towards the huge bay of Ningaloo, a whale shark mecca and with luck, a seahorse haven.


Filed under: Uncategorized — hhamilton @ 3:36 pm

Shark Bay Diving

From the Log of David McGuire, Field Associate

Inspired by Norah’s discovery, we take a small open boat out early next morning to Eagle Bluff, skating south over the clear shallows of the bay. An hour later we sighted a few small sharks including a Wobegong (which woefully I did not see, having struggled with a flooded camera housing); some nice schools of trevally, emperor fish, blue damsels and several species of wrasses among the coral heads: but no sygnathids.

Diving in Sharks Bay

It was nearly uninhabited, a flat blue bay and a lot of red dirt. The pelicans and cormorants are a pied black and white and nest on the small islands off the bluff. But for their coloration they could be the same as those that live off Baja and California. Hours in the water are fruitless and the weather is turning from pleasantly sunny and mildly cool to a blustery breeze and dark wet menacing clouds.

The following day we boated in the rain to Morgan reef – a “muck dive” in the shipping lane in about 15 meters, where we thought we had a chance of observing syngnathids. The squally weather with a strong wind blowing against the tide turned into a steep chop and strong surface current. As Dive Master, I tended the vessel while the others dived the bottom: surfacing 45 minutes later in another fruitless venture. Perfect habitat, lots of food – where were our fish?

Two researchers

On the way in, we snorkeled the shallow sea grass for over an hour but again without luck. With the rain and wind and absence of fish, we packed up and bid our adieus and headed North to the town of Carnavaron, another 300 k away. Typical of what we have experienced throughout the expedition, the crew at Ocean Park were so friendly and helpful and it was hard to depart before the promise of a BBQ with the crew: but our duty to find syngnathid fish prevails.


Filed under: Uncategorized — hhamilton @ 3:21 pm

Diving with Sharks and Syngnathids in Sharks Bay

From the Log of David McGuire, Field Associate

Monday we drove another 300 kilometers North to the town Denham: a small town on the Peninsula bisecting Sharks Bay. Heading north past the last coastal town of Geraldton, the road veers inland so there will be no diving at this stage, but a landscape of the outback rolling past in a montage of red dirt, green scrub, Eucalyptus trees and dead kangaroos. At last we hit the coast at Sharks Bay and after inspecting the ancient stromatolite mats and shell beds of accreted clams at Hamelin, we continue scouting the peninsula looking for likely dive sites. Pulling into a touristy spot on the remote highway before Denham, we spoke to the manager at the Sharks Bay Ocean Park, a marine tourist outpost before the major resort areas of Denham and Monkey Mia. This small aquarium holds a 2.7 m tiger shark, a Loggerhead sea turtle, and several other local animals from the bay. The young manager was extremely helpful and we hired his boat and dive gear and were able to camp out near the aquarium on the bluff overlooking the sea. Norah’s first snorkel at sunset revealed two sea moths and a pipefish living in the sea grass beds bordering the rocky beach: a promising sign.

Shark's Bay

From Norah Saarman, Shark’s Bay

“We pull up in the evening. The low scrub and savannah stretches to meet the calm water of Shark Bay. I am a little nervous as I pushed out into the shallow water of the bay, my mind cognizant of the wild things lurking beneath the dark ripples. Once my mask enters the underwater world, my thoughts slow to meet the rhythm of the sea. I observed the seagrass beds, marcro-algae and rippled sand bottom. Something catches my eye; Pegasus volitans, a sea-moth. Pegasids are distant cousins of the seahorses, but their armor body-plates and mystical translucent wings give the impression that they come from the same far-off lands. I am excited, and swim back to shore to share the good news. With such a good start, I can’t help but re-enter the water even as the sun kisses the blue horizon. Another Pegasid! And then, the fish we have traveled so far to find; the endemic Festucalex scalaris. The pipefish gives me a look of indifference as if he is protected by a magical barrier. The camouflage this group of fishes wears is admirable. I am lucky to have paused over this particular bed of sea grass among the other densely covered bottom of Shark’s Bay. What a lucky find.“

Sea Moth   Photo by Graham Short


Filed under: Uncategorized — hhamilton @ 3:04 pm

Road Trip to Exmouth

From the Log of David McGuire, Field Associate

RV on way to Exmouth
The first dive is a propitious beginning to the expedition and we are now ready to drive north to explore the open coastline. We rent the “Apollo”; a camper van that will be our home for the next two weeks for the road trip over 1000 kilometers north. Loading our dive gear, camera equipment and collecting nets we head north along Highway one skirting the remote coastline of this remarkable continent. Driving on the left hand side of the road and shifting with the left hand takes a small adjustment, but once we exit Perth the road is wide open. Early Sunday we depart Fremantle on our expedition, driving 300 kilometers north to camp alongside the Murchison River in a rustic campground. Road camping is an Australian national pastime, and the caravan parks and highways are filled with trailers, modest RVs and combis driven by people of all ages. People are so friendly they wave to their fellow campers as we pass. The funny thing is, nearly everyone passing along the narrow two lane highway is a fellow camper and my wrist gets weary from the Australian salute.


Filed under: Uncategorized — hhamilton @ 2:59 pm

Road Trip to Exmouth, Fremantle

From the Log of David McGuire, Field Associate

Exploring, Explaining and Protecting the Natural World.

In our efforts to fulfill the mission of the California Academy of Sciences, we are exploring a remote coastline in Western Australia searching for a strange and unique family of fish. I am with Dr. Healy Hamilton of the California Academy of Sciences as part of an expedition collecting and identifying seahorses and their relatives – the sea dragons and pipefish. Besides Dr. Healy and me, the team includes Academy Research Associate Graham Short and UC Santa Cruz Graduate Student Norah Saarman.

research group

Our first dive took place early Saturday morning near the port city of Freemantle with the help of Kevin Smith – a local parks manager and colleague studying the Syngnathidae, the family of fish that include seahorses, sea dragons, pipehorses and pipefish. Here in the antipodes it is near the winter solstice and the morning is sunny but cool as we gear up to dive into the calm waters beneath a jetty. Threading our way among the monofilament cast by the fishermen overhead, Norah discovers a seahorse, Hippocampus subelongatus, a species found only in southwestern Australia. My job is to help with the logistics including dive safety, and to document the expedition and the animals in the wild.

specimen2   Photo by Graham Short

Somewhere in the murk Healy and Graham are finding other individuals of the same species and taking small snips of tissue from the tiny fins for DNA analysis. (See Healy’s Blog Post) Kevin collects two pipe fishes Vanacampus sp. and Histiogamphelus sp. – cousins to seahorses in the sea grasses nearby. The animals are remarkably cryptic and it takes a practiced eye to distinguish the thin camouflaged fish among the thick meadow of sea grass.


Filed under: Uncategorized — hhamilton @ 1:55 pm

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