Editor: Nicholas Gould, 80 Cleveland Road, Chichester, West Sussex PO19 7AF, UK.
Phone and fax + 44 (0)1243 782803.

International Zoo News is published by the North of England Zoological Society, Chester Zoo, Caughall Road, Chester CH2 1LH, UK This magazine is for the exchange of news, information and ideas between the zoos and aquariums of the world. By arrangement with the Editor, this page and IZN page 1 (see link above) highlight some of the features on aquariums in recent IZN issues. You can email Nicholas Gould at IZN directly from here: ngouldizn@aol.com

Sea World, Surfers Paradise, Queensland, Australia

Shark Bay, one of the largest man-made lagoon systems for sharks, will open at Sea World at Christmas 2003. The complex will consist of touch tanks, a tidal pool, a large reef pool and a large shark pool holding six million litres of water. As guests enter Shark Bay they will be given the opportunity to interact with some of the inhabitants of one of the specially designed touch pools. They will not only look, learn and listen, but will also get to touch the tidal pool creatures.

The water from the touch pools will overflow into a tidal pool, home to our smaller rays, then surge over into the large Snorkel Lagoon – the reef tank. This will be a themed environment, housing smaller shark species such as leopard sharks, blacktip reef sharks, nervous sharks, sandbar whalers and epaulette sharks, together with shovelnose rays, cowtail rays, and a large variety of colourful reef fish and invertebrates. In this large reef environment, guests will be able to dive and snorkel amongst the sharks as part of a new set of animal adventure programs. They will also be able to watch the animals from above water level, providing a visual opportunity similar to the view from the deck of a boat.

The largest lagoon will house the larger and more dangerous species, including magnificent tiger sharks and spectacular bull whaler and dusky whaler sharks. This lagoon will provide the animals with the space to complete a 60-metre-long swim-glide pattern without the fear of bumping into objects or other animals. This distance is essential for larger sharks, which use the glide movement to rest.

The two large pools, Shark Lagoon and Snorkel Lagoon, will appear as one large pool from above. In reality, below the bridge will be two large acrylic panels that separate the large sharks from the smaller reef species. This will give the participants in the new Snorkel with the Sharks program the feeling that they are in the same tank as the larger sharks. Snorkellers and divers will also have the opportunity to learn about these animals through an innovative underwater education signage trail that they can follow while swimming around the pool.

When guests visit the underwater viewing areas of Shark Bay, their first visual encounter will be through four 10 metre by 3 metre acrylic panels. These panels are 180 mm thick and weigh over 6.5 tonnes. Television monitors will show footage on conservation issues, management and general information on the animals displayed in Shark Bay.

The filtration system will combine multiple filtration techniques, as used in other Sea World exhibits – mechanical, biological, chemical, ozone and UV technology. The filtration system will turn over the entire water volume of Shark Bay every 90 minutes – a rate of about 1,000 litres every second.

Miranda Creak in ARAZPA Newsletter No. 59 (August 2003)
IZN October/November 2003

Sea World, San Diego, California, U.S.A.

For the first time in the park's 39-year history, we have successfully incubated and hatched sea turtles, something only two other aquariums are known to have done. Assistant Curator of Fishes Carl Jantsch notes that the attempt at reproduction was successful because aquarists simulated the natural breeding environment found in the wild.

On 1 April, it was noticed that one of the female green sea turtles (Chelonia mydas) in the Sea Turtle Beach display had dug a pit and deposited her eggs. Staff collected 105 eggs from the nest and incubated them behind the scenes in coral sand over a water bath at the park's freshwater aquarium. Between 4 and 10 June, the turtles began to hatch and surface. In the wild, newly hatched sea turtles head directly for the ocean. At Sea World, aquarists took the 21 surviving hatchlings from the nest, put them in water and began feeding them a diet of squid, krill, shrimp, fish and a special `turtle chow'. After monitoring the turtles' progress for several weeks, aquarists deemed them healthy and put them on display in late June.

Communiqué (American Zoo and Aquarium Association), September 2003
IZN October/November 2003

Monterey Bay Aquarium, California, U.S.A.

Monterey Bay recently became the first aquarium worldwide to display approximately one dozen spotted comb jellies (Leucothea pulchra). These delicate animals are a shallow-water species found only in the Pacific Ocean between central California and the Sea of Cortez. They can grow to over a foot [30 cm] long and possess distinctive brownish-orange spots covering their translucent bodies. Scientists are as yet unsure of the spots function. As with all comb jellies, the animals generate flashing patterns of rainbow light as white light passes through the pulsing ctene-rows, the hair-like appendages that help them to move through the water. Marine scientists have also long been fascinated by the spotted jelly's complex feeding and propulsion behaviors. Staff aquarists, who are thrilled to be able to exhibit these never-before-seen animals, hope to have them on exhibit for several months.

Additionally, Monterey Bay recently added the only two giant Pacific bluefin tuna (Thunnus orientalis) on exhibit outside of Japan to their million-gallon [3.8-million-liter] Outer Bay exhibit. Weighing in excess of 300 pounds [136 kg] each, the benchmark weight for a tuna to qualify as ‘giant’, the tuna are sharing their exhibit with the largest collection of open-ocean animals in the world, including the only oceanic whitetip shark (Carcharhinus longimanus) on exhibit in the world, two species of dolphinfish, black (or Pacific green) sea turtles (Chelonia [mydas] agassizii), pelagic stingrays, soupfin sharks and a number of 200-pound [90-kg] yellowfin tuna. The bluefins will continue to grow, adding about 50 pounds [22 kg] a year, and could eventually tip the scales at 1,000 pounds [450 kg]. Eleven other bluefin tuna in the exhibit could become giants sometime in the next three years.

Communiqué (American Zoo and Aquarium Association), February 2003

At feeding time, they wiggle excitedly, pop their heads out of the water and gently nudge each other to get the fish that staff hand-feed them. Then they push their perpetually smiling faces forward so that the trainers can rub their big round heads.

These aren’t the belugas. These are sharks, four- to five-footers who will soon take up residence in Shedd’s new Wild Reef exhibit. But, says aquarist Rachel Wilborn, ‘these zebra sharks [Stegostoma fasciatum] are like puppy dogs.’ Not so their neighbors and distant relatives, the wobbegongs (Orectolobus ornatus and O. japonicus), which are known as ‘toe biters’ in Australia. The most aggressive of Shedd’s sharks, wobbegongs bite first and don’t let go to ask questions later. Incidents usually involve incautious waders or divers who tread on these well-camouflaged bottom-dwellers.

That is just a taste of the diversity that will be found in the 400,000-gallon shark habitat in Wild Reef, the permanent exhibit opening in the new south wing of the aquarium in 2003. It will also house whitetip reef sharks (Triaenodon obesus), sandbar sharks (Carcharhinus plumbeus) and blacktip reef sharks (C. melanopterus) – 30 to 35 sharks in all – along with hundreds of brightly colored and boldly patterned groupers, trigger-fishes, wrasses, jacks and other Indo-Pacific reef fishes.

The sharks, however, will be the main attractions, and thanks to a 50-foot-long, five-inch-thick acrylic window that begins at the floor and arches 12 feet overhead, guests will have a dizzying view of them. ‘The blacktips like to hang out in the upper water column, especially when it’s dark,’ says Wilborn. ‘During the day they come down into the lower water column.’ At any time, these sleek, taut sharks will zoom through the pool, in part because it is the way they hunt, but also because they are obligate ‘ram ventilators’ – they must keep swimming, literally ramming water across their gills, to breathe.Like room-mates working different shifts, when the blacktips leave their night-time post in the upper waters, the sandbars will rise from slowly roaming the bottom to take their place. Sandbars look like your ‘true’ shark, with a high first dorsal fin and eye-catching teeth, but they are not especially aggressive. Staking out the middle waters will be the whitetip reef sharks. Like the wobbegongs and zebras, but unlike the blacktips and sandbars, they can remain stationary for stretches of time because they’re able to pump water across their gills by opening and closing their mouths.

‘It’s going to be a really nice array,’ says Wilborn. ‘People will see sharks at all levels.’ Except at feeding time, that is – then they’ll be swarming overhead. ‘We’re going to be feeding right above where the window arches over people’s heads.’ To maintain order among five species with different feeding strategies, from frenzy (the blacktips) to wiggling (the zebras, which naturally squirm into reef crevices in search of fish and shellfish), all of the sharks are being trained, using the same methods developed for the belugas and dolphins. Just as a dolphin is cued to swim to a feeding station when shown her individual shape, or target, three of the shark species have already learned to identify and swim to a specific shape. Wilborn says that sharks can recognize color and shape. ‘But to what extent, we aren’t sure,’ she adds, ‘so we use both. And we use color combinations with high contrast.’ The whitetips respond to a red plus sign with white stripes, the blacktips go into pre-feeding frenzy over a green-and-black-striped rectangle, and the zebras have learned to come to a black circle. As well as separating them for feeding, this enables aquarists to move groups from one section of the huge habitat to another, useful when divers are cleaning, or to direct the sharks into the adjacent isolation pool for physical exams.

‘We’re limited in what we can do in training the blacktips, because they have to keep on the move, they don’t want to be touched, and they get spooked easily,’ says Wilborn. ‘The zebras are the easiest to train – they actually follow a buoy, and have to touch it to get their food.’ The zebras respond not only to edible rewards but also to tactile ones: they like to have their noses rubbed. ‘You can’t do it with every shark, obviously, but these guys [actually one male and two females] are very easy to handle and work with.’ She draws the line at tongue scratching, which delights those other big smiling marine animals, the belugas. ‘The zebra sharks have great dispositions. But they do have big sharp teeth.’

Abridged from Karen Furnweger in WaterShedd Vol. 23, No. 4 (Autumn 2002)