A Review of White Sharks Recorded from Sydney Harbour

A Review of White Sharks (Carcharodon carcharias) Recorded from Sydney Harbour.

By John West – Posted August 2013.
Curator, Australian Shark Attack File
Taronga Zoo.

I have often been asked if the white shark (Carcharodon carcharias) occurs in Sydney Harbour in relation to shark attacks? Sydney Harbour is generally considered an estuarine environment with a large area of oceanic quality water between the heads and inside the harbour for several kilometres. While I have not heard of a white shark being scientifically identified in Sydney Harbour since the Australian Shark Attack File was established in 1984, I felt that a review of this subject may shine some light on the question.

In my review I sought advice from the Australian Museum, the Sydney Game Fishing Club, CSIRO, NSW Fisheries and other shark research scientists to determine if a white shark has actually been scientifically verified in Sydney Harbour.

Method

A review was undertaken of white sharks recorded in Sydney Harbour over the last 200 years. The search included shark related web sites, museum collection records, literature databases, historical media web sites, game fishing club records and discussions with prominent shark researchers from NSW Fisheries and CSIRO.

An extensive review of the Trove Digitised Newspapers website was undertaken for any references to white sharks sightings reported in the media during the period from 1800 to 1950.

The Australian Shark Attack File was reviewed for data on white shark attacks recorded in harbours, estuaries, lakes or rivers in Australia.

Search Outcomes

A search of the records of the Sydney Game Fishing Club (SGFC) did not find a record of a white shark being captured in Sydney Harbour (SGFC pers. comm.).

The Australian Museum has three white shark specimens in the collection from the general area of ‘Port Jackson’ (deposited 1888). Its list of fishes from Sydney Harbour webpage (Ref 1) notes one reference of a white shark being found in Sydney Harbour and states ‘‘One only from Watsons Bay, (Stead 1963)’.

A search of the Trove Digitised Newspapers website (Ref 2) for any references to white sharks in Sydney Harbour (1800 – 1950) found only a single Sydney Morning Herald (SMH) article from 26th May 1927. The article referred to a five metre “Great White Death” being captured inside Sydney Heads on 22nd May 1927 that had apparently followed a French mail steamer through the heads to Watson’s Bay. This specimen was identified by ichthyologist Mr David Stead.

In the book ‘Sharks and Rays of Australian Seas’, by David Stead (1963), Stead identified a 14 foot (4.26m) white shark captured off Watson’s Bay (no date).

A review of the Australian Shark Attack File for white shark attacks in Australia found two records involving a white shark occurring in an estuary (near the heads). The attack location was just inside the heads at Port Stephens (NSW). However, no other cases of white shark attacks have been recorded as taking place in a harbour, estuary, lake or river.

Discussion

The three Australian Museum specimens obtained in 1888 have a general location as ‘Port Jackson’ (Sydney Harbour) but no indication that they were actually captured in Port Jackson. The latitude and longitude associated with the records had been added years later as a estimate and likely presumed the location to be from the area of Port Jackson (John Paxton pers. comm.). The 1963 reference on the Museums web site relates to the book ‘Sharks and Rays of Australian Seas’, by David Stead (1963) which details the capture of a white shark near Watson’s Bay (see below).

A single Sydney Morning Herald (SMH) article from 26th May 1927 entitled ‘Shark Haul – A School in the Harbour’ (Ref 2) was found in the search of the digitised historical media database. The article reported that a white shark was captured ‘in the Harbour’. The 1927 article described the capture of a 16 foot 6 inch (5m) ‘Great White Death’ inside Sydney Heads on 22nd May by local fisherman Charles Messanger. The article reported that the large shark was following a French mail steamer through the heads when captured. However, the article does not indicate how far past the heads or into the harbour the shark travelled before being captured. This large shark was identified by Mr David Stead.

In the book ‘Sharks and Rays of Australian Seas’ (Stead 1963) Stead notes the capture of a 14 foot (4.26m) white shark that had followed a ‘steamer’ through the heads and was captured off Watson’s Bay (no date). It is the consensus of several shark experts that the 1927 SMH article and the description in Stead’s book (page 41) are of the same white shark capture event even though the lengths differ.

Stead wrote that a white shark could follow a vessel into a harbour and states ‘The fact is, as suggested elsewhere, that the white pointer is a most infrequent visitor to the sheltered waters and then only penetrates for a short distance. Probably, in most cases, it follows some large vessel which it has been trailing for some miles beforehand’.

Juvenile white sharks (< 3.0m) have occasionally been verified as occurring in large lakes and estuaries on the east coast of NSW and Victoria. In one case a juvenile white shark was photographed in Lake Illawarra in 2010 and the photo was positively identified by Barry Bruce (a senior research scientist with the CSIRO). Juvenile white sharks have also been photographed by a fisherman in Lake Macquarie (Nov 2012 & July 2013) also verified by Mr Bruce. A newspaper article was found relating to a four metre white shark that ‘wandered’ into Tallebudgera Creek (QLD) in May 1987 and was reportedly killed by a spearfisherman. However, how far into the creek the shark travelled is unknown.

A number of sharks (including white sharks) have been tagged in east coast waters with specially coded acoustic tags by research agencies including the CSIRO and NSW DPI. These tags can be detected by moored underwater acoustic receivers of which there are hundreds deployed along the coast and inside some estuaries. Acoustic receiver data is shared between researchers as part of the Australian Animal Tracking and Monitoring System (http://imos.org.au/aatams.html). These tagging programs are shedding light on the broad-scale movements and habitat use of sharks in Australasian waters. Such programs may, in future, establish whether white sharks are transient visitors to areas like Sydney Harbour, but to date there have been no recorded entries into Sydney Harbour by tagged white sharks.

Other large free swimming shark species (considered harmful or potentially harmful to humans) have been reported or reliably observed in Sydney Harbour and include the tiger shark (Galeocerdo cuvier), bull shark (Carcharhinus leucas), dusky shark (C. obscurus), silky shark (C. falciformis), bronze whaler shark (C. brachyurus) and sevengill shark (Notorynchus cepedianus). In 2009 a blue shark (Prionace glauca) was filmed in shallow water 10km in from the heads at Glebe and there are also reliable sighting of mako sharks (most likely Isurus oxyrinchus) reported feeding in the harbour (Dennis Reid pers. comm.).

Conclusion:

Large white sharks (>3.0) tend to be nomadic, feed on a variety of fish as well as marine mammals and migrate many thousands of kilometres. They are not known to spend long periods at any one site unless suitable food sources are available (eg around seal breeding colonies) where they may revisit a particular feeding site periodically (Bruce and Bradford 2013, Duffy, et al, 2012, Domeier and Nasby-Lucas, 2008). However, juvenile white sharks (<3.0m) are predominately fish eaters and known to congregate at nursery sites along the Australian east cost and may follow fish into large estuaries and lake systems to feed. Reports of this species occurring in estuarine environments are uncommon and most likely relate to the abundance of juveniles congregating in nearby nursery areas (Bruce and Bradford, 2012).

While there are many reports of large white sharks being captured by big game fishermen off Sydney heads in the late 1800’s and early 1900’s, with many large specimens being brought back to Watson’s Bay to be weighed, there seems to be only one reliable record of a white sharks being captured inside the entrance to Sydney Harbour (SMH 26th May 1927).

It is feasible that white sharks could enter Sydney Harbour but to date there are no confirmed or reliable reports, records or observations locating white sharks past the area near Watson’s Bay (approximately 900m inside the heads).

Over the last 222 years (to date) there have been no recorded shark attacks on humans attributed to white sharks in Sydney Harbour.

Reference:

Ref 1. http://australianmuseum.net.au/Fishes-of-Sydney-Harbour

Ref 2. http://trove.nla.gov.au/ndp/del/auth

Bruce, B. D. and Bradford, R. W. (2013). The effects of shark cage-diving operations on the behaviour and movements of white sharks, Chacharodon carcharias, at the Neptune Islands, South Australia. Marine Biology 160: 889-907.

Bruce, B. D. and Bradford, R. W. (2012). Spatial dymanics and habitat preferences of juvenile white sharks in eastern Australia. In Domeier, M (ed) Global Perspectives on the Biology and Life History of the Great White Shark. CRC Press, Boca Raton, FL. pp 225-253.

Domeier, M. L. and Nasby-Lucas, N. (2008). Migration patterns of white sharks Chacharodon carcharias tagged at Guadalupe Island, Mexico, and identification of an eastern Pacific shared offshore foraging area. Marine Ecology Progress Series 370: 221-237.

Duffy, C. A. J., Francis, M. P., Manning, M. and Bonfil, R. (2012). Regional population connectivity, oceanic habitat and return migration revealed by satellite tagging of white sharks (Chacharodon carcharias) at New Zealand aggregation sites. In Domeier, M (ed) Global Perspectives on the Biology and Life History of the Great White Shark. CRC Press, Boca Raton, FL. pp 299-315.

Stead, David, G. (1963). Sharks and Rays of Australian Seas. Pub by Angus & Robertson, pp. 211.