for Sydney and Kormoran between 1974 and 1991, when the ship was based in Fremantle. conducted another search in July 1997. However, all RAN surveys were restricted to the continental shelf, as the navy did not possess the technology to search the seabed off the shelf effectively. The searches were not exhaustive. They were primarily a response to civilian claims that the wreck site was at a particular location, with the survey ship sent to prove or disprove the claim. Other searches were conducted by aircraft of the Royal Australian Air Force carrying magnetometers; again, these were only in response to claims of possible locations. In 1990, the Woods Hole Oceanographic Institution (WHOI) was approached to join a Western Australian Maritime Museum-led search for Sydney and Kormoran, which was agreed to on the condition that the search area be narrowed considerably. This was attempted at a 1991 forum: although the battle's location was generally agreed upon, because the exact fate and time of sinking for Sydney were unknown, the possible site could not be more accurately determined. WHOI staff did not believe that the search area could be sufficiently narrowed down—shipwreck hunter Robert Ballard commented that searching for the ships could not be described as a needle in a haystack "because the haystack has not yet been found"—and the WHOI withdrew its support. Following the 1999 government report into the Australian cruiser's loss, which recommended that a seminar be organised to attempt again to identify the most likely search area for the warships, the HMAS Sydney Location Seminar was organised by the RAN's Sea Power Centre and held at the Western Australian Maritime Museum. However, participants in the seminar could not agree on whether the battle location given by the Germans (referred to as the "northern position") or a point off the Abrolhos Islands (the area for the battle advocated by supporters of the "southern position") was more likely to contain the two ships. In 2002, a coalition of oil and gas companies involved in the North West Shelf Venture performed a gratis search of eight suspected targets in the proposed southern area. No evidence was found of shipwrecks at any of the eight sites, although supporters of this search area claimed that the equipment used was defective and rejected the findings. Subsequent examination of the most popular southern site by DOF Subsea Australia vessel SV Geosounder in March 2007