Some of the most decorative and elusive fish in Australian waters belong to the family 'Syngnathidae'. Species in the Syngnathidae family include seahorses, pipefish, seadragons and pipehorses. Unlike their other bony fish relatives, syngnathids share a characteristic elongated semi-flexible stiff body, covered with bony plates and rings for protection instead of scales. Specialised tubular snouts with a small mouth at the tip vary by species according to their preferred specialised prey type. These bizarre and wonderful creatures are found principally in seagrasses, coral reefs and mangrove habitats in tropical, subtropical and warm temperate habitats where they feed largely on small crustaceans.
Seahorse habitats are among the most threatened in the world. More than 25 million dead and live seahorses are traded globally on an annual basis with around 95% of these being used in traditional medicines; aquarium and souvenir trade make up the rest. In the 1990s, some seahorse populations were observed to shrink between 25 to 50 percent over five years.
On 23 November 2004 Project Seahorse and Guylian Chocolates launched a new Australian seahorse project at Sydney Aquarium. Dr Keith Martin Smith, the leading scientist from Project Seahorse, will be assisting marine scientist David Harasti with his PhD project that aims to investigate the effectiveness of marine protected areas in protecting syngnathid species. This project is being undertaken in collaboration with Dr Bill Gladstone from the University of Newcastle and Dr Tim Glasby from NSW DPI and is being sponsored by MARES scuba diving equipment, Project Aware and Project Seahorse.
Project Seahorse, established in 1996, is a team of biologists and social workers committed to conserving and managing seahorses, their relatives and their habitats while respecting human needs. The team is composed of about 40 professional team members working in Australia, Canada, Hong Kong, Philippines, Portugal, U.K., and U.S.A. Project Seahorse has also managed projects in South Africa and Vietnam, and maintains strong collaborations with colleagues in many more countries.
Guylian, internationally famous for its chocolate seashells and pralines, has committed more than $1 million over five years to support Project Seahorse to conduct fundamental research. Guylian's funding has enabled Project Seahorse to increase its professional capacity for seahorse studies all over the world with special new focal studies of seahorse behaviour and ecology in Australia and Portugal.
This PhD research project will examine the biology and ecology of the White's Seahorse (Hippocampus whitei) that can be found from Port Stephens to Sydney Harbour and it is common in both these sheltered waterways. The White's Seahorse (Hippocampus whitei) is a shy seahorse species that can be commonly found in the waters of Port Stephens if divers know where to look for them. The scientific genus for seahorses is 'Hippocampus' which also means 'horse sea-monster' in Greek. This seahorse species is endemic to the waters of New South Wales; endemic meaning that it is only known to occur in this region.
The White's Seahorse has an elongate bony body and long snout that it uses to suck up small prey such as mysid shrimp. They swim slowly upright in the water, or wrap their tails around objects such as seagrass fronds or sponges to hold them in place for feeding or for stabilisation during turbulent water conditions such as storms and currents. A quick fact on seahorses is that they are considered to be the slowest moving fish species in the ocean!
The White's Seahorse uses camouflage to blend in with their surroundings before using an ambush predatory feeding behaviour on small crustaceans. Their colouration varies considerably and generally matches the colour of the plant, coral or sponge that they are living on. The reproductive strategy shared by seahorses is unique in that the female deposits eggs in the male's body for incubation and the male then gives birth. The male White's Seahorse carries eggs in pouch-like openings and only the males care for the young. In seahorses, pregnancy lasts about two weeks to one month, the length decreasing with increasing temperature. At the end of gestation the male goes into labour (usually at night), pumping and thrusting for hours to release his brood. Young are miniature adult seahorses, independent from birth, and receive no further parental care.
This research will focus on the syngnathids within Port Stephens and will examine the distribution and abundance of Hippocampus whitei within the Fly Point - Halifax Park Aquatic reserve and similar habitats outside the reserve. Surveys will also examine the habitat preference and depth range for Hippocampus whitei and also monitor the distribution and abundance of other syngnathid species within Port Stephens (such as the Tiger Pipefish Filicampus tigris). Some of the primary objectives of the research project are:
The seahorse research commenced in July 2005 with Dr Keith Martin-Smith and David Harasti conducting initial baseline surveys to gain an understanding of the distribution and abundance of the White's Seahorse within Port Stephens. The seahorse surveys involve recording various key characteristics such as their location, habitat, depth range, sex, size and colour. Additionally, the seahorses are being tagged with unique identifying marks known as visible implant fluorescent elastomer (VIFE) that has been used worldwide for tagging syngnathids and fish. During the tagging process the animal's size is measured using a ruler and the sex of each individual is recorded. VIFE markers are applied just beneath the skin using a needle and the markers are less than 2mm in size. On subsequent resightings in the wild the seahorses are identified and their location recorded.
Additionally, the study will involve mapping of the habitat areas of Hippocampus whitei and other syngnathids within and outside the aquatic marine reserve and underwater photography will be used to photograph individual animals. The seahorse monitoring in Port Stephens will occur for approximately 3 years. Project AWARE has recently provided their support for this seahorse monitoring project and have provided a grant to assist with the community seahorse training and surveys. Community scuba divers will be trained in seahorse and pipefish identification, how to conduct scientific surveys and how to search for and record animals. Divers will survey along transects, search in grids and conduct timed swims whilst towing a GPS to record their location. Surveys will be conducted within the aquatic reserve and outside the reserve in similar habitats so comparisons can be made. Divers will search through seagrass and sponge garden habitats and record syngnathid observations. The data collected by the divers will be analysed by scientists from Project Seahorse & the University of Newcastle as part of the PhD research.
For further information on seahorses visit the Project Seahorse website (http://www.projectseahorse.org/) or the International Marine Species Database (http://www.speciesspotlight.com/).