Why the Australian and New Zealand navies were small

Why were the Australian and New Zealand navies so small at the outbreak of war?

Treaty restrictions were not the main obstacle; the dominions chose limited defence spending while relying on British naval protection.

The London Naval Treaty did not prevent the dominions from buying more ships, including sloops, corvettes, and additional cruisers. Britain encouraged larger local forces and had room within the treaty structure for more dominion construction. Australian and New Zealand governments were reluctant to fund those fleets and relied heavily on the wider British naval umbrella. Those spending choices limited the size of the dominion fleets.