Marine Biodiversity of Southern Sydney Harbour's Journal

Who doesn't love a good shark photo? We have now completed our fourth month of the Marine Biodiversity of Southern Sydney Harbour project and I'd like to congratulate user eschlogl (once again!) for his Photo Observation of the Month of a Port Jackson Shark (Heterodontus portusjacksoni) from Camp Cove. Despite being an avid diver in Sydney for 25 years, this is the first time Erik observed juvenile Port Jackson Sharks here. Port Jackson Sharks usually live in rocky environments on, or near, the sandy/muddy bottom. In some instances they may be resting ajacent to seagrass meadows. This species occurs in southern Australian waters from southern Queensland south to Tasmania and west to the central coast of Western Australia. In fact, genetic studies suggest that there may be two populations in Australia, one occurring from southern Queensland to New South Wales and the second from north-eastern Victoria to Western Australia. These sharks have an oviparous reproductive mode, meaning that they lay eggs, in this case dark brown spiral egg cases that hatch after approximately one year. The female actually manipulates the egg case in her mouth once laid to attach it to rocks and crevices in order to anchor it in place. This species is not to be confused with the the Crested Hornshark (Heterodontus galeatus), which has large prominent crests above the eyes and lacks dark markings on its side.

This journal post was written by project leader and iNaturalist member, Dr Joseph DiBattista.

Just an update that the running contest dates based on the submission of photographs to iNaturalist will be extended to August 1, 2023 in the interest of giving a fair shake to as many participants (new and old) as possible. As a reminder, small prizes, including gift vouchers from local dive providers (Sydney Dive Charters, Dive Centre Bondi, PRO DIVE ALexandria) and restaurants (Clove Lane, Randwick), will be awarded to top users at each of the three sites in the categories below, on or just after August 1, 2023.

Archival Photos: eligibility period based on photos taken prior to June 1, 2022. This category is particularly well suited to avid snorkelers, SCUBA divers, and underwater photographers that regularly visit one or all three of the sites in southern Sydney Harbour.

*New Photo Submissions: eligibility period based on photos taken between October 15, 2022 and August 1, 2023. This category is well suited to anyone with a keen eye and underwater camera!

*Note that the contest for “New Photo Submissions” at Shark Beach will only start when it reopens to the public due to current lack of access.

This journal post was written by project leader and iNaturalist member, joseph_dibattista Dr Joseph DiBattista.